From the end of July and the beginning of August this year, the price of lead began to accelerate upward. In just half a month, it quickly jumped from 18,000 yuan/ton to 20,000 yuan/ton. The price of downstream lead-acid batteries also rose. What are the factors that lead prices to rise, and what are the impacts on downstream lead-acid batteries?From a longer-term perspective, lead prices have been in an upward channel for nearly a year, and from a recent perspective, the wave of increases since May 18 can be roughly regarded as the third stage of this longer cycle.In this stage, from the end of July and the beginning of August, the price of lead began to accelerate upward. In just half a month, it quickly jumped from 18,000 yuan/ton to 20,000 yuan/ton. The price of downstream lead-acid batteries also rose. What are the factors that lead to the rise in lead prices, and what are the impacts on downstream lead-acid batteries?Factors that cause the sharp rise in lead prices1. The fourth round of environmental protection supervision has been launched recently. The recycled lead industry has been affected by the environmental protection supervision. The three-no refineries have basically been shut down, and the production capacity has been greatly reduced, resulting in a tight supply of market supply.2. From late July to early August, production was restricted by high temperature weather.3. Glencore, an international mining giant, recently lowered its annual lead production plan by 5%.4. The grade of lead ore has declined.5. According to data released by the World Bureau of Metal Statistics (WBMS) on August 16, the global zinc market had a supply shortage of 370,000 tons from January to June 2017, and a supply shortage of 223,000 tons in 2016. From January to June 2017, the global lead market had a supply shortage of 195,000 tons, and the supply shortage for the whole year of 2016 was 172,000 tons. The price of lead-acid batteries has risen along with the price of leadAlthough the lead-acid battery industry is currently in the traditional peak consumption season, the pressure from cost and environmental protection still makes major recycling and manufacturing companies suffer.On August 11, as the state officially launched the environmental protection inspection in Zhejiang Province, in addition to the three-no small factories that were almost completely shut down, some qualified large enterprises were also not immune. Almost 90% of the industry's production enterprises were ordered to increase production and rectify. Among them, Changxing in Zhejiang accounts for about 60% of the country's lead-acid battery production capacity.It is understood that at the press conference held by the State Council Information Office on June 3, Li Ganjie, Vice Minister of the Ministry of Environmental Protection, said that the most severe measures would be used to rectify the lead-acid battery industry and the recycled lead industry, and strive to curb the frequent occurrence of lead pollution accidents.At the same time, the continuous rise in lead prices has gradually pushed up the production cost of lead-acid batteries, and lead-acid batteries have also followed the price increase. Lead-acid batteries account for a large portion of the cost in the DC power supply system, which will inevitably lead to price adjustments for the power supply system. If you need it urgently, what are you waiting for?

As spring returns, all parts of China are restoring production in an orderly manner while keeping a close eye on epidemic prevention and control. In the context of the COVID-19 pandemic, in order to reduce contact transmission between people, the demand for "AGV robots replacing people" has been stimulated, and service AGV robots have taken the lead in epidemic prevention in the fields of medical care, distribution, inspection, and household use. The service robot industry is currently in the early stages of development, and this epidemic is expected to become a catalyst for the development of the AGV robot industry.Under the COVID-19 pandemic, the value of service robots has been highlighted. For example, the relevant reports we have seen have been successfully used in the following scenarios:1. Medical care: Robots replace medical staff to complete disinfection, medical guidance, and drug delivery. Typical cases include the Titanium Disinfection Robot and DJI Disinfection Drone.2. Delivery: Robots deliver meals to quarantined people. Typical examples include the delivery robots of Yunji, Qinglang, and Pudu.3. Inspection: In crowded areas, robots automatically patrol to monitor people's body temperature, entry and exit, mask wearing, etc. Typical examples include UBTECH's police inspection robot.4. Home use: Disinfect the home environment.In order to avoid cross-infection and close contact between people, AGV smart cars are also widely used in the manufacturing industry. For factories in the manufacturing industry, manual labor has many shortcomings in modern manufacturing. For example, for some low-end jobs, the younger generation is not willing to do repetitive labor. In some gravity-type jobs, human physical strength is limited, and carrying large objects will reduce the efficiency of the production line. In comparison, automation has great advantages in the manufacturing industry. In some environments, robots (AGV) can complete production tasks more smoothly than humans. There are many application scenarios for industrial AGV robots in the manufacturing industry, and mobile robots (AGV) that perform logistics handling work are used more and more frequently.At the same time, with the rise of intelligent manufacturing models, future factories must be automated and intelligent, and this mobile robot (AGV) will be one of the key roles. Usually, mobile robots (AGV) can interact with manufacturing execution systems to achieve error prevention, traceability and other functions. Mobile robots (AGV) can be better integrated into intelligent manufacturing systems to achieve product component delivery in each production link, ensuring that the entire production line operates with high efficiency.In addition, the continuous development of emerging technologies such as the Internet of Things and artificial intelligence has brought many benefits to AGV mobile robots. Manufacturers are using vision and laser navigation to improve the recognition ability of mobile robots (AGV) in industrial scenarios. By adding artificial intelligence algorithms, AGV robots can achieve autonomous operation and have the ability to make independent decisions, so as to better cooperate with work. We can even use voice commands, face recognition and other technologies to easily call AGV robots to enter production tasks, further improving the efficiency of equipment use.AGV robots consume their own power while working, and need to be charged like mobile phones and electric vehicles to ensure normal operation. Xinxiang Tianheng Electric is a company specializing in AGV smart charging stations and AGV brush plates and blocks (charging connectors). It has many years of design and production experience and can design and produce according to customer power requirements. Facing the rise of the AGV industry, Tianheng Electric has a long way to go!

Technological innovation, technological breakthroughs, and industrial promotion in the field of new energy have never stopped. It is in full swing and lively. In this mixed and emerging market, how to distinguish and choose a more suitable power battery pack is particularly important. Different types of battery packs such as lead-acid batteries, lithium power batteries (lithium iron phosphate, ternary lithium power batteries, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide), nickel batteries (nickel-cadmium sintered batteries, nickel-hydrogen maintenance-free batteries, iron-nickel batteries, zinc-nickel batteries), fuel cells, aluminum-air batteries, supercapacitors, etc., have different characteristics due to different material systems. Under each category, the material combination is different, and the process of each manufacturer is different, which has derived countless categories. And each type has its own unique advantages and disadvantages, and has its own application field in the power market. How to choose the power battery for the online AGV car in such a complicated situation?So, first of all, let's talk about the application field and technical application requirements of the online AGV car.With the intelligentization of industry, the curve of labor costs has risen. Online AGV trolleys have been widely used in automated logistics, smart factories, large storage systems and places that are not suitable for long-term work of personnel, and have broad prospects. Online AGV trolleys must meet the requirements of safety, continuous workability, stability, intelligence, miniaturization and low-cost operation mode.The operating characteristics of the online AGV car, in the shallow discharge mode, use less battery capacity to achieve high-power shallow discharge operation of the AGV car. When charging, use a large current for a short time, and put it into work after quickly replenishing the power. Example: The solution designed by our company for a company, the smart charging station uses wireless data link to understand the battery module status of the online AGV car in real time. When the SOC of the battery module of one of the AGV cars is lower than the set value, the AGV car automatically goes to charge. At this time, the smart charging station automatically calculates the charging current according to the battery status and the required charging time (such as 3 minutes), and supplements the charging with a charging current not higher than 2C. After charging, it usually works for about 30 minutes before charging again, and so on, to achieve uninterrupted work.This efficient, intelligent, and low-cost operation mode has very strict requirements on the battery module. The battery is required to have continuous high-speed high-current charging reception capability, high current discharge capability, high safety in this mode, working reliability, long cycle life, wide temperature range, complete protection functions, and high cost performance.Lead-acid batteries do not have high-current charging capabilities, lithium cobalt oxide has poor safety and high cost, and iron-nickel batteries have low specific energy and large size. Fuel cells and aluminum-air battery technologies are not fully mature and are not considered.However, in some cases, AGV cars also use lead-acid batteries.At present, the more mature products of online AGV car power batteries include ternary lithium power batteries, lithium iron phosphate batteries, and nickel-hydrogen maintenance-free power batteries. Its characteristics are as follows:Chart 1NiMH power maintenance-free battery has good applicability in wide temperature range, good high current charging and discharging capacity, strong explosive power, superior performance, but large size and high price. It is only suitable for application under special conditions.Lithium battery technology is relatively mature and is increasingly widely used.In terms of cost, the preparation process of lithium iron battery is complex, the yield is low, and the consistency is poor. Due to the different characteristics and particle size of the material itself from the ternary, the specific energy is low. This is why the material cost is cheap but the price is not lower than the ternary. The current technological trend is to continue to mix manganese, nickel and other substances on the basis of iron lithium for modification, which has achieved better performance, and this has also blurred some of the boundaries of the material.Ternary power batteries are used in online AGV vehicles. They have high specific energy, small size and long cycle life, which are very suitable for the application of conventional online AGV vehicles.Our company's supporting power battery module adopts nano-conductive technology and diaphragm ceramic anti-short-circuit technology, with better large current charging and discharging capabilities, complete BMS protection control, and more safe and reliable.

The application range of DC distribution panels is very wide. Important places such as power stations, hydropower stations, and substations have made full use of DC distribution panels. Its role is very obvious. It can not only be used as a power source for signals or accidents, but also as a backup power source for many places, bringing many conveniences to people's lives.In the DC panel of the substation, battery packs, chargers, rectifiers, AC power supplies, DC distribution voltages, etc. constitute the DC panel. Different voltage levels are directly related to the number of batteries. For example: 110V DC voltage needs to be composed of 9 12v batteries; 18 12v batteries are required to form a 220v DC voltage.According to the regular inspection and management of the AC uninterruptible power supply equipment used in the dispatching automation system, the battery operation time is subject to a discharge test every 6 months within 2 years, and a discharge test every 3 months for more than 2 years, and a deep discharge test is conducted at least once a year (capacity greater than 50%).Maintenance equipment:1 dedicated battery discharge instrument, 1 battery pack with a capacity of more than 220V40AH, 1 temporary charger above 20A, 1 single battery activation instrument, and 1 dust blower.Daily maintenance1. Keep the battery clean, and apply oxidant to the positive and negative terminals2. Check the operating status of the battery pack:(1) Operating temperature rise:The battery does not heat up during floating charge. If individual batteries are found to be hot, the cause should be checked immediately and handled in time. If the entire battery pack is found to be hot, the operating status of the battery should be checked first (both strong charging and discharging have a certain temperature rise), whether the floating charge current is too large or the battery pack has an external micro short circuit, etc. If problems are found, they should be handled in time. For common battery faults, please refer to the battery section;(2) Check the connection points of the battery pack to see if the contact is tight and whether there is oxidation, and apply vaseline oil.Fault handling Common battery faults can generally be divided into external faults and internal faults. Common external faults include obvious cracks in the battery shell, damaged seals, and corrosion of positive and negative poles. Common internal faults include sulfation of positive and negative plates, shedding of active substances, automatic discharge, and short circuit of plates.I. Plate sulfationIf the battery is undercharged for a long time or discharged for a long time without charging, a layer of white coarse grains of lead sulfate will be produced on the plate. This phenomenon is called "lead sulfation", or "sulfurization" for short. This coarse and hard lead sulfate grain has poor conductivity and large volume, which will block the pores of active materials, hinder the penetration and diffusion of electrolyte, increase the internal resistance of the battery, and fail to supply sufficient starting current during startup.Batteries with mild plate sulfation can be charged for a long time with a small current of 2A~3A, that is, overcharge, or the active materials can be reduced by a full discharge and full charge cycle. Batteries with heavy sulfation can be eliminated by desulfurization charging. For severely sulfided batteries, the plates should be replaced or scrapped.II. Self-dischargeThe phenomenon that a fully charged battery consumes its own energy and gradually loses its power when it is not used is called self-discharge. Self-discharge of batteries is inevitable. For fully charged batteries, the general discharge range is within 1% per day and night. If the loss of self-discharge per day and night exceeds 2%, it should be regarded as a self-discharge fault.  In order to reduce the self-discharge of the battery, use sulfuric acid and distilled water that meet the standards to prepare the electrolyte; during use, the battery surface should be kept clean and dry, and the filling hole cover should be covered to prevent impurities from falling into the battery. For batteries with self-discharge failure, the battery can be completely discharged, the electrolyte can be poured out, the plate group can be taken out, the partition can be pulled out, and it can be reassembled after rinsing with distilled water, and new electrolyte can be added.Three. Plate active material sheddingActive material shedding mainly refers to the shedding of pbO2 on the positive plate, which is one of the reasons for premature damage to the battery. Batteries with minor active material shedding can be cleaned and the electrolyte replaced before continued use. If the shedding is serious, the plates should be replaced or scrapped.IV. Precautions1. Strictly abide by the charging specifications of various charging methods.2. When charging, the wires must be connected reliably. The battery wire should be connected first, and then the power switch of the charger should be turned on. When stopping charging, the power should be cut off first, and then the battery wire should be removed.  3. During the charging process, closely observe the voltage and density changes of each single cell battery to timely judge its charging degree and technical status   Xinxiang Tianheng Electric Technology Co., Ltd. is a company specializing in the research and development and production of high-frequency switching DC power supplies, phase-controlled DC power supplies and other series of products. With many years of design and production experience, it can design and produce according to customer power requirements. The company's products are widely used in power, railways, communications, logistics automation, national defense, petrochemicals, metallurgy, coal mining and other fields.

  (1) Cleaning and inspection of the DC panel, rectifier DC power supply device and its DC circuit should be carried out by two persons, one of whom should supervise the work to prevent injuries or damage to equipment due to mistakes.        (2) During cleaning and inspection, if further inspection of some operating components is required or defects need to be corrected, the work must comply with Article 164 and relevant provisions of Chapter 4 of the "Electric Power Safety Work Regulations" (Electrical Part of Power Plants and Substations). If a component in a DC circuit is replaced under power, measures should be taken to prevent the DC load from being interrupted. (3) If a fault occurs in the DC system during cleaning, inspection or defect handling, the system should be stopped immediately and kept in its original state to find out the cause.        (4)Any supply<a href="http://www.xxsthdq.com/" When the DC panel and the rectifier power supply DC device of the circuit breaker electromagnetic operating mechanism are stopped for maintenance, inspection or defect treatment, the automatic reclosing device of the closing power supply circuit breaker should be shut down. When the work of the rectifier DC power supply device is completed and restored, the relevant automatic reclosing device can be put into operation.  

 The DC panel is an important component of the normal operation of the substation. It can continuously transmit stable DC power to the substation and meet the power demand of the operation of power equipment. From the actual application situation, the performance of the substation battery DC panel in terms of service life and power supply is difficult to meet the standard requirements, which restricts the performance of the DC power supply operating system. The study found that the use of supercapacitor DC panel can effectively solve the problem of DC power supply. The improved supercapacitor DC panel has greatly improved in performance, life, stability and other aspects, and has obvious advantages over the battery DC panel. The DC power supply operating system is referred to as "DC panel". It provides stable DC power to various power equipment in the substation and is also the core power supply for modern substations. DC panel technology not only protects the normal operation of the power system, but also plays a good protective role in the stable operation of other components. An in-depth analysis of the problems existing in the DC panel of the substation can ensure the continuous supply of DC power and create favorable conditions for the normal operation of power equipment and related modules. The active introduction of DC panel technology in the power industry can accelerate the development of automation and intelligence of substations and improve the overall efficiency of substation equipment operation. 1. Problems with DC panels in current substations The DC panels used in domestic substations are composed of charging cabinets, charging modules, monitoring modules, battery packs, step-down silicon chains and other structures. Each module plays an important role in the DC power supply. From the perspective of industry development trends, DC panels are DC systems operating under digital control mode, which have multiple functions such as control, protection, management and monitoring for DC power supply in substations. At present, DC panel technology used in substations has remote monitoring, control and other functions, which facilitates the on-duty personnel to control the operation of the power system. However, some problems with DC panels should also attract the attention of technicians. Cadmium nickel batteries and sealed lead-acid batteries are commonly used DC panels. The main problems are as follows: (I) Cadmium nickel battery DC panel 1. Performance problems. Substations need to use a large number of battery modules to output electrical energy through the DC bus to maintain normal DC power control. For example, in general, a large substation DC bus outputs 220V, which requires about 200 battery combination modules. However, during the production and processing of cadmium nickel batteries, the manufacturer cannot guarantee that the charging and discharging performance of each battery is completely consistent, and the combination of 200 batteries will produce obvious differences in characteristics. The charging power supply connected to the cadmium nickel battery DC screen after the DC power supply is supplied is consistent, and the load discharge object is the same. This feature leads to the weakening of the performance of local cadmium nickel batteries and reduces the function of the entire battery combination module. 2. Life problem. Due to the defects of the cadmium nickel battery combination material, the DC screen is essentially in a "floating charge state" during operation. At this time, the service life of the cadmium nickel battery DC screen depends on the charger. According to the provisions of the industry standard, the manufacturer guarantees the life of cadmium nickel batteries for more than 10 years, but the specific use records are only about 5 years. The reason for the shortened life of the battery DC screen is that the excessive subduction current will cause the water in the electrolyte to be electrolyzed into hydrogen and oxygen, which is the fundamental cause of the battery explosion. If the cadmium nickel battery DC screen is not specially treated, it is easy to cause accidents. Therefore, the service life of the DC screen will be affected by other factors. 3. Oxidation problem. During the use of the cadmium nickel battery DC screen of the substation, redox reactions will also occur, causing the cadmium nickel material to undergo a chemical reaction to generate cadmium oxide, resulting in a continuous decrease in the effective area of the plate. In order to avoid the occurrence of redox reactions, substation staff will regularly conduct "activation tests" on the batteries for analysis. In the activation test, the battery needs to be charged and discharged. The operation at this stage will cause polarity reversal and cause the battery to be scrapped. In addition, while the redox reaction destroys the performance of the cadmium nickel DC screen, it will also bury safety hazards for the stable operation of the substation. For example, if the battery is completely installed in the cabinet, it is easy to cause safety accidents such as burning and explosion. (II) Sealed lead-acid battery DC screen Driven by science and technology, domestic substation DC screen technology continues to develop, and many new battery products have also been widely used in substations. Based on the shortcomings of the cadmium nickel battery DC screen, companies began to use sealed lead-acid batteries, referred to as "valve-controlled batteries." This product is superior to nickel-cadmium batteries in terms of quality, performance, price, and maintenance. For example, valve-controlled batteries do not require excessive maintenance or water treatment, which provides great convenience for substation operators. However, the "fully sealed" state of the DC panel also causes many problems, especially when the battery is observed and inspected, it is difficult for maintenance personnel to update the device in time. In addition, due to the relatively backward domestic valve-controlled battery technology, the life of the product is not guaranteed when it is used in substations, and the operating conditions for the valve-controlled battery DC panel are very strict, which has caused great difficulties for the normal production of substations. 2. Factors affecting the life of valve-controlled batteriesService life is an important factor restricting the promotion of valve-controlled batteries. Large, medium, and small substations using this power supply device will consider the service life in order to control the operating cost of the substation. According to the analysis of test data, the factors affecting the service life of valve-controlled batteries are concentrated on temperature factors, discharge factors, water loss factors, corrosion factors, and so on. (I) Temperature FactorsAlthough there are still obvious shortcomings in the use of valve-regulated batteries in substations, they have been greatly improved compared with nickel-cadmium batteries, creating better conditions for the operation of the DC power supply operating system of substations. The life of valve-regulated batteries is very sensitive to temperature. Manufacturers require that the operating environment temperature of the battery be 15℃~25℃. When the ambient temperature exceeds 25℃, the battery life will be shortened by half for every 10℃ increase. (II) Discharge FactorsOver-discharge of batteries is another important factor affecting the service life of batteries. When the battery is over-discharged to zero output voltage, a large amount of lead sulfate inside the battery will be absorbed to the cathode surface of the battery, forming sulfation of the battery cathode. The more sulfate formed on the cathode plate, the greater the internal resistance of the battery, and the service life of the valve-regulated battery will be greatly shortened. (III) Corrosion FactorsGrid corrosion is an important reason affecting the service life of batteries. In the open circuit state, the lead alloy is in direct contact with the active lead dioxide, and they are immersed in sulfuric acid solution together. In the overcharged state, water is consumed in the positive electrode due to the oxygen evolution reaction, and H increases, which leads to an increase in acidity near the positive electrode. The battery grid will become thinner, the capacity will decrease, and the service life will be shortened. (IV) Floating charge factor Most of the batteries used in substations are in a long-term floating charge state, which will cause the anode plate of the battery to passivate, the internal resistance of the battery to increase sharply, and the actual capacity (Ah) of the battery to be far lower than its standard capacity, thereby greatly shortening the actual backup power supply time that the battery can provide and reducing its service life. (V) Water loss factor Battery water loss is also one of the factors that affect its service life. Battery water loss will lead to an increase in the specific gravity of the electrolyte, corrosion of the battery grid, and a reduction in the active substances of the battery, thereby reducing the capacity of the battery and shortening its service life. When the water loss is 5.5%, the capacity drops to 75%; when the water loss reaches 25%, the capacity basically disappears. III. Tests on supercapacitors for DC panelsIn order to prove the advantages of supercapacitors in DC panels of substations, several common test cases are listed, and the comprehensive performance characteristics of supercapacitor DC panel technology are analyzed based on the test results. (I) Test on closing circuit breaker with supercapacitorThe nominal capacity of supercapacitor is 0.82F, and the withstand voltage is 280V. Test on closing circuit breaker with supercapacitor. Test method: disconnect the closing power supply of 615 cabinet; connect the two outlet terminals of the charged supercapacitor to the contact of the closing contactor; simulate the normal closing mode, press the closing button, and record the number of closings and the voltage at the capacitor terminal. A total of 15 closings were made, and each time the closing was successful. Result: When the capacitor is charged to 10% of the rated voltage 95, the CD-Ⅱ electromagnetic mechanism can be reliably closed for more than 8 times, and each closing causes the capacitor terminal voltage to drop by 5V. (II) Supercapacitor charging time testThe initial charging of the supercapacitor is equivalent to a short circuit if no current limiting resistor is added. The manufacturer recommends using a 1000W iodine tungsten lamp as a current limiting resistor. Its cold resistance is nearly 10 times smaller than the hot resistance, which meets the requirement that the current limiting resistor should be reduced after the capacitor voltage rises. The following test data are all measured data with a 1000W iodine tungsten lamp in series. Results: Different charging power supplies have an impact on the charging speed, but no matter what power supply, it only takes 3 minutes for the capacitor to charge from zero volts to the rated voltage. After that, the long-term floating charge current changes from 0 to 10mA. (III) Supercapacitor self-discharge test After the supercapacitor is charged to 242V, it is completely disconnected from the load and the capacitor terminal voltage is measured at the same time every other day. Results: The terminal voltage drop speed is related to whether it has been floated. Without float charging, it reaches 2 to 3V/h in the first few hours, that is, it drops 2 to 3V per hour. After half an hour of float charging, the self-discharge speed slows down significantly, which may be related to the fact that the charge inside the capacitor has not had time to be evenly distributed. In normal use, the supercapacitor is in a long-term floating charge state, and the effective voltage can be maintained for 3 days (72 hours) after the load is completely disconnected. 4. Performance comparison between supercapacitor DC panel and battery DC panelAccording to the test results of supercapacitors used in DC panels, it not only gets rid of the shortcomings of traditional battery DC panels, but also significantly improves the efficiency of substation power system operation, and provides sufficient DC power for operators' system control and transformation. In order to verify the many advantages of supercapacitor DC panels, this article focuses on performance and makes a comprehensive comparison between supercapacitor DC panels and battery DC panels in terms of failure, life, maintenance, etc. (I) Comparison of failuresNo matter which type of battery is used in the substation, it needs to be equipped with a corresponding discharge device when in use. This is an important condition to ensure that the battery continuously supplies DC power. Judging from the test results, the failure rate of the discharge device used in the traditional battery DC panel is significantly higher than that of the supercapacitor DC panel, which is not conducive to the stable operation of the daily operation of the substation. The supercapacitor discharge device is simpler in structure, and it is more convenient to modify or discharge it. (II) Comparison in life spanAfter the battery is used up, it needs to be charged before it can be used normally. Long-term charging will shorten the service life of the battery, which is generally shorter than the standard service life of 5 to 10 years, which will affect the stable performance of the battery DC screen. The service life of the supercapacitor DC screen is longer because it does not have the problem of overcharging and over-discharging. During the production period, the maximum charging voltage can meet the maintenance needs, which effectively avoids the shortening of the service life of the supercapacitor. (III) Comparison in maintenanceFrom the perspective of DC screen maintenance, the daily maintenance workload of the substation is large. Not only must the battery be regularly tested and updated, but the line connection inside the battery must also be comprehensively monitored, which poses great difficulties to the staff. However, the supercapacitor DC screen does not require excessive maintenance when used in the substation. After the DC screen device is fully tested and meets the standards at the initial installation, it can be used for a long time. In terms of performance recovery, the battery needs to recover for several hours after discharge before it can supply power normally, while the supercapacitor can restore power in only 3 to 5 minutes. Maintain the normal power supply of the substation. V. ConclusionThe DC power supply operating system is the basic guarantee for the normal operation of the substation. It can timely transmit current to various power equipment for supply and use. With the accelerated pace of social modernization, my country's substation construction is facing new reforms and optimizations. Various battery DC screens are gradually replaced by other forms of devices, which is of great help to the future innovation and development of substations. Supercapacitor DC screen is an advanced technology for substation DC screens. It is significantly superior to traditional battery DC screens in terms of performance, maintenance, life, and failure. It should be fully promoted and used in the power industry. Xinxiang Tianheng Electric has a complete R&D technical team and an experienced after-sales team. If you have any questions during use, you can directly call us. Your satisfaction is our greatest mission!

From the end of July to the beginning of August this year, the price of lead began to accelerate upward. In just half a month, it quickly jumped from 18,000 yuan/ton to 20,000 yuan/ton. The price of downstream lead-acid batteries also rose. What are the factors that lead prices to rise, and what are the impacts on downstream lead-acid batteries?From a longer-term perspective, lead prices have been in an upward channel for nearly a year, and from a recent perspective, the wave of increases since May 18 can be roughly regarded as the third stage of this longer cycle.During this period, from the end of July to the beginning of August, the price of lead began to accelerate upward. In just half a month, it quickly jumped from 18,000 yuan/ton to 20,000 yuan/ton. The price of downstream lead-acid batteries also rose. What are the factors that lead to the rise in lead prices, and what are the impacts on downstream lead-acid batteries?Factors that caused the sharp rise in lead prices1. The fourth round of environmental protection supervision has been launched recently. The recycled lead industry has been affected by the environmental protection supervision. The three-no refineries have basically been shut down, and the production capacity has been greatly reduced, resulting in a tight supply of market goods.2. From late July to early August, production was limited by high temperature weather.3. Glencore, an international mining giant, recently lowered its annual lead production plan by 5%.4. The grade of lead ore has declined.5. According to data released by the World Bureau of Metal Statistics (WBMS) on August 16, the global zinc market had a supply shortage of 370,000 tons from January to June 2017, and a supply shortage of 223,000 tons in 2016. From January to June 2017, the global lead market had a supply shortage of 195,000 tons, and a supply shortage of 172,000 tons in 2016.Lead-acid battery prices rise with lead pricesAlthough the lead-acid battery industry is currently in the traditional peak season for consumption, the pressure from cost and environmental protection still makes major recycling and manufacturing companies suffer.On August 11, as the state officially launched the environmental protection inspection in Zhejiang Province, in addition to the three-no small factories that were almost completely shut down, some qualified large enterprises were also not spared. Almost more than 90% of the industry's production enterprises were ordered to increase production and rectify.Among them, Changxing area in Zhejiang accounts for about 60% of the country's lead-acid battery production capacity.It is understood that at the press conference held by the State Council Information Office on June 3, Li Ganjie, Vice Minister of the Ministry of Environmental Protection, said that the most severe means will be used to comprehensively regulate the lead-acid battery industry and the recycled lead industry, and strive to curb the frequent occurrence of lead pollution accidents.At the same time, the continuous rise in lead prices has gradually pushed up the production cost of lead-acid batteries, and lead-acid batteries have also followed the price increase. Lead-acid batteries, in the DC power supply system, occupy a large cost, which will inevitably lead to the adjustment of the power supply system price. If you are in urgent need, then what are you waiting for?　　Tianheng people look forward to extensive cooperation with customers from all walks of life to share our products and success. 　　Business consultation: 0373-3313097, 18637333097　　After-sales service: 0373-3313023　　Company address: No. 110, Qianjin Road, Muye District, Xinxiang City　　 

Analysis of DC system grounding detection method and improvement of detection device       The DC system of power plants and substations is an independent power supply, which is not affected by generators, plant power, station transformers and changes in system operation mode. It provides reliable and stable uninterrupted power supply for the control circuit, signal circuit, relay protection, automatic device and emergency lighting of the power system. It also provides operating power for the opening and closing of circuit breakers. Therefore, the DC power supply system plays a vital role in the safe operation of the substation and is the prerequisite for the safe operation of the substation. The DC power supply system in the power system adopts the ground insulation operation mode. When a point of grounding occurs in the DC system, it does not cause direct harm and can continue to operate, but the potential danger is very large. An alarm must be given immediately and searched; otherwise, when another point of grounding occurs, there may be very serious consequences. 1. About the grounding of DC system and its hazards1.1 What is grounding of DC system    DC power supply is a power supply with polarity, that is, the positive pole and the negative pole of the power supply. The "ground" of DC power supply is just a concept of neutral point for DC circuit. If the insulation resistance between the positive or negative pole of the DC power supply system and the ground is reduced to a certain set value, or lower than a certain specified value, then we say that the DC system has a positive grounding fault or a negative grounding fault.1.2 Why is the DC system grounded?    The DC system of power plants and substations is connected to many devices and complex circuits. In the long-term operation process, due to changes in the environment, climate changes, aging of cables and connectors, problems with the equipment itself, etc., DC system grounding is inevitable. Especially during the construction or expansion of power plants and substations, due to various problems in construction and installation, it is inevitable that hidden dangers of DC system grounding faults will remain.1.3 Classification and hazards of DC system grounding    Due to the complex connection of the DC system feeder network, it can be divided into positive grounding and negative grounding according to grounding polarity; according to the type of grounding, it can be divided into direct grounding (also known as metal grounding or full grounding) and indirect grounding (also known as non-metal grounding or semi-grounding); according to the grounding situation, it can be divided into single-point grounding, multi-point grounding, loop grounding and insulation reduction. According to research, positive grounding may cause the circuit breaker to trip incorrectly. Since the circuit breaker tripping coils are all connected to the negative power supply, when positive grounding occurs, it may cause the circuit breaker to trip. Negative grounding may cause the circuit breaker to refuse to trip.    Operation practice also found that DC grounding will not only cause relay protection to malfunction or fail to operate, but even cause DC-controlled equipment to malfunction or fail to operate, and even damage the equipment, resulting in serious consequences such as large-scale power outages and system collapse. For example, on July 6, 2000, in heavy rain, a DC grounding occurred in a 220kV hub substation in Hebei. The 273-1 electric knife switch automatically opened during operation without any signal. After investigation and analysis, it was found that the 273-1 knife switch control box was damp due to water seepage, and it was confirmed that the knife switch was malfunctioned due to DC two-point grounding. In a 500kV hub substation, due to heavy snow, the DC two-point grounding caused the station's 380V AC power control switch to trip. In a 220kV hub substation in Guangxi, the circuit breaker malfunctioned due to DC two-point grounding. These are all power grid faults caused by DC system insulation problems.2. Common methods for finding and eliminating DC system faultsThere are many detection technologies for ground faults in DC systems, and the implementation principles are also different. They can be summarized into the following methods:2.1 DC bus bridge methodThe detection device developed using the bridge method is relatively simple, which is equivalent to adding two balancing resistors to the positive and negative DC bus to form a balanced bridge; it only gives an alarm for the ground fault of the DC system, and cannot indicate the straight line and grounding resistance value where the fault is located, and the function is too monotonous. When field maintenance personnel troubleshoot, they usually use the manual pulling method. Pull open the DC load circuits supplied by the DC panel in turn for a short time. When a certain circuit is cut off, the fault disappears, indicating that the fault is in the circuit. The operability is relatively poor, especially for important loads, short-term power off is not allowed. Therefore, the detection device using this method is only suitable for DC cabinet systems in very low-end distribution rooms.2.2 Low-frequency signal injection method    After a ground fault occurs in the DC system, a low-frequency signal is injected between the fault bus and the ground. The low-frequency current flows out of the signal generator, flows through the ground fault feeder, and returns from the grounding point. Use a clamp-type current detector to detect each feeder. Find the grounded feeder and then find the grounding point.    This method successfully achieves the search for DC grounding points without power outages, but its detection accuracy and sensitivity are greatly affected by the distributed capacitance of the DC system. The maximum capacitance of the feeder branch can reach several microfarads. When the probe is measured at a certain point, due to the presence of capacitive current, it will be difficult for the operator to determine whether it is capacitive current or grounding resistance current. Using this method to detect grounding resistance often results in misjudgment or large errors in the measured and calculated grounding resistance.2.3 Frequency conversion signal injection methodFrequency conversion signal injection is actually still low-frequency signal input, but the injected signal is a low-frequency signal with alternating frequency. Then, the clamp-type current probe is used to detect the change in the branch resistive current amplitude to determine the grounding branch and the fault point. By injecting a signal with constant amplitude and variable frequency, the resistive current in the feeder branch is indirectly calculated. However, through on-site use inspection, the effect is still not ideal, and the reason is still distributed capacitance. In addition, the injection of low-frequency signals will increase the voltage ripple factor of the DC system.2.4 Magnetic modulation DC leakage current detection method     Using magnetic modulation leakage current sensor, the positive and negative lines of the DC system feeder branch pass through the CA ring core, and the current provided to the load, there is a triangular wave constant current excitation current in the CA leakage current sensor, excitation winding, detection winding; when the current on the positive and negative lines is not equal, the leakage current sensor has a leakage current size direction signal output. Due to the principle of balanced bridge, the magnetic modulation leakage current sensor can only monitor asymmetric DC grounding faults, and is powerless when the positive and negative insulation resistances drop equally or their values are close DC screen

DC panel debugging method:1. First check whether the primary and secondary circuit wiring is correct - mainly to check fatal errors, such as the weak point interface is connected to strong power, the DC signal should be connected but the AC signal is connected, and there is a short circuit problem.2. Avoid the above reasons, disconnect all circuit breakers and fuses, connect the AC power supply, test whether the AC dual power switching device works normally, and whether the lower port voltage of the dual power switching device is normal.3. After the AC part is tested normally, close the AC switch of the charging module in turn, observe whether the module starts normally and measure the module output voltage and polarity.4. After the charging module starts normally and the output voltage and polarity are correct, turn on the battery pack switch and each bus switch, measure the voltage and polarity of the battery pack switch bottom port, closing bus, and controlling bus, and observe whether the voltage meter is overturned.5. Turn on the feed switch once, and measure the terminal voltage and voltage polarity corresponding to the feed switch respectively.6. The above content is the debugging of the primary circuit. After the above steps are measured and debugged, turn on the monitoring power supply.7. After the monitoring is powered on, observe whether the monitoring display is normal and whether each detection module is working normally.8. After the monitoring device is powered on normally, first check the alarm information on the monitoring display. If there is an alarm message, find the relevant problem according to the alarm message. If not, check the voltage value displayed by the monitoring device, the current value with load, the switch quantity information, etc.9. After checking and testing the main analog and switch information on the monitor, start testing the insulation alarm of the DC bus and the branch grounding resistance. Generally, the 220V system can be tested with a 25-100K resistor, and the 110V system can be tested with a 7-100K resistor.10. Battery inspection test. It is best to connect all the batteries of the specified number of routes to the battery inspection to test the overall performance. If the on-site conditions are not enough, you can take a single battery and test it in turn.So far, the debugging is complete. The rest is to check whether the components are installed and tightened, whether the wires and components are loose, and whether there are process problems.  

As low-carbon economy and environmental protection are included in the government's "12th Five-Year Plan", the issue of renewable energy power generation grid connection, which has been progressing slowly, has also begun to enter the mandatory stage.The relevant person in charge of the Energy System Research Office of the Energy Research Institute of the National Development and Reform Commission revealed to the reporter of "Huaxia Times" that low-carbon economy and environmental protection will be included in the "12th Five-Year Plan" by the government. For this reason, the government will take some mandatory policy measures to promote the promotion and use of renewable energy and clean energy. Ren Dongming, deputy director of the Renewable Energy Development Center of the Energy Research Institute of the National Development and Reform Commission, also said that in order to achieve the goal of clean energy accounting for 15% of the total primary energy consumption, the state will issue renewable energy grid connection and power generation quotas to power grids and power generation companies, and subsidize the construction costs of the power grid.Forced access to the grid through a quota system"The energy situation facing my country is very severe, and China has established the goal of low-carbon economic development. The 12th Five-Year Plan will be included in the low-carbon plan, and the goal of reducing emissions by 40%-45% in 2020 will have a comprehensive impact on the social economy. There is no doubt that energy conservation and emission reduction will be included as a binding indicator in the 12th Five-Year Plan." Jiang Kejun, director of the Energy System Research Office of the Energy Research Institute of the National Development and Reform Commission, pointed out.As an important support for the low-carbon economy, renewable energy power generation has been required by the government since 2007 to give priority to the acquisition of renewable energy power generation projects, including hydropower, wind power, biomass power, solar power, ocean power and geothermal power. Among them, except for large and medium-sized hydropower, renewable energy generators do not have to participate in the grid bidding, and power grid companies need to give priority to acquisition and arrange dispatch.But the current situation is that the problem of power grid companies' unwillingness to purchase renewable energy power has not been solved.Ren Dongming said that in order to achieve the goal of clean energy accounting for 15% of the total primary energy consumption, the country is studying and issuing a series of promotion policies to solve the problem that the power grid is unwilling to purchase electricity during the large-scale installation of wind power and solar power.It is reported that the country will implement a quota system, that is, a full guaranteed purchase system for renewable energy power generation. At present, relevant departments are studying and formulating management measures for this quota system, which requires that a certain amount of electricity purchased by power grid companies comes from renewable energy generation, or that a certain proportion of power generation by power generation enterprises comes from renewable energy.It is said that both the State Grid and the Southern Power Grid will bear the relevant renewable energy power generation quotas, and then distribute these quotas to provincial or regional power grid companies, and then distribute them downward. The state will set up a renewable energy development fund, from which a certain amount will be drawn to subsidize power grid construction.Grid connection ratio will rise to 15%In addition to issuing mandatory policies to ensure the grid connection of renewable energy power generation, the government will also clarify the grid connection ratio of renewable energy power generation.As early as September 2009, President Xi Jinping proposed at the United Nations Climate Change Summit that China will vigorously develop renewable energy and nuclear energy, and strive to achieve a non-fossil energy share of about 15% of primary energy consumption by 2020. According to the existing plan, the proportion of non-fossil energy in energy consumption will reach 10% in 2010.According to Meng Xiangan, vice president of the China Renewable Energy Society, 15% is exactly the target for the proportion of clean energy in my country's total primary energy consumption, and according to the plan, this target will be broken down. Among them, hydropower accounts for about 8%, nuclear power accounts for about 4%, and solar power and wind power account for about 3%. The specific planning goals are: hydropower installed capacity reaches 300 million kilowatts, nuclear power installed capacity reaches 80 million kilowatts, wind power reaches 150 million kilowatts, and photovoltaic power generation reaches 20 million kilowatts. At the same time, in 2020, clean energy will account for 15% of the total primary energy consumption in my country. By 2030, clean energy will become an important alternative energy source, and by 2050, clean energy will become the main energy source.It is reported that the above plan has been reported, but has not yet been approved."If the 15% target is to be achieved, the government will also invest relevant funds to solve the technical difficulties of energy storage and large-scale grid connection of intermittent renewable energy such as wind and solar energy." An expert from the Macroeconomics Office of the Chinese Academy of Social Sciences told reporters.    Government sets up fund subsidiesIn addition to the government's determination to develop renewable energy in terms of policy, it also plans to arrange more financial support for this field.According to Ren Dongming, the Ministry of Finance has drafted the collection and management methods of the "Renewable Energy Fund". The government hopes to support smart grids, off-grid power generation in remote areas and various new technology research and development through this fund. The method may be released in the near future.It is reported that the fund will share the cost of the power grid's acquisition of renewable energy electricity, so that the power grid will have the motivation to complete the acquisition. Its funding sources include special funds arranged by the national fiscal year and additional income from renewable energy electricity prices collected in accordance with the law.Xu Huaqing, director of the Energy Environment and Climate Change Research Center of the Energy Research Institute of the National Development and Reform Commission, also revealed that the proportion of renewable energy connected to the grid has increased from 10% to 15%. It is necessary to strengthen the power grid and improve the self-regulation ability of the power grid to reduce and overcome its intermittent defects. Therefore, the government will subsidize the investment in upgrading the power grid.According to the data provided by Jiang Kejun, in these areas, as of 2008, the national investment in technology research and development has reached 38 billion, while the United States' investment in research and development is also 38 billion US dollars."At present, coal costs account for more than 2/3 of the cost structure of thermal power, but the continuous soaring of coal prices in recent years has led to the continuous increase in the operating pressure of the thermal power industry, excessive asset-liability ratio, and even continuous losses. The increase in the proportion of renewable energy power generation will also help alleviate the contradiction between coal and electricity under the background of the continuous strengthening of energy resource prices, and help the government to further promote electricity price reform and rationalize the electricity price transmission mechanism." An expert from the Macroeconomics Office of the Chinese Academy of Social Sciences told reporters.The relevant person in charge of the China Electricity Council believes that with the increase in the proportion of renewable energy power generation in the power grid, it will also be beneficial for China to transform its power structure from over-reliance on coal power to increasing the proportion of non-fossil energy, continuously increase the proportion of clean energy, and accelerate the development of nuclear power and other renewable energy power generation while efficiently developing my country's hydropower resources.  

Valve-regulated lead-acid maintenance-free battery is a new type of battery in recent years. It is easy to install, simple to use, and requires little maintenance. It is suitable for small and medium-sized substations and distribution rooms.Lead-acid valve-regulated battery is relatively delicate in terms of its characteristics. It cannot be charged with high current and high voltage, nor can it be discharged at full capacity. This is determined by the material. Therefore, the voltage and current are limited during charging. When the current and time limit reach a certain voltage during discharge, the discharge needs to be stopped (single cell 1.85v×108).Charging: Calculate the charging current according to the battery capacity, charge at 0.1 times the battery capacity, the single cell voltage cannot exceed 2.35V, and the total voltage of 18 batteries is 253.8V. For example: for a 100AH capacity battery, the current cannot exceed 10A during charging; charging voltage: the single cell voltage cannot exceed 2.35V×108＝253.8V, so the voltage of the entire battery group needs to be limited to 253.8V.Discharge: According to the battery capacity, the discharge current is 0.1 times the capacity, and the voltage is 200V. For example: 65AH discharge is 6.5A, voltage is 200V, discharge time is 10 hours, and it is completed.Detect the capacity of the battery: current × time = capacityFor example: 65AH battery: 6.5×10＝65AHInsufficient discharge time means insufficient capacity. For example, if there are 18 batteries and the voltage is 200V, the discharge must be stopped.According to the characteristics of lead-acid batteries, the following charging and discharging operation steps are written for user reference:1. During overhaul, stop the AC power and ensure safety.2. If there is a discharge switch, connect it to the lower line of the switch; if there is no switch, connect the external load to the battery pack switch; 1000-1500W discharge current. (Ensure that the battery discharge current is 0.1 times the capacity)3. Stop discharging when the battery pack voltage reaches 200V.4. Send AC power, charge, and fully charge in about 10 hours.5. If the capacity is not enough, you can do another cycle. Discharge--charge to detect capacity.6. When the battery capacity is insufficient, please repair or replace it in time to ensure normal power supply.