There is a speed called China Speed, and there is a pride called China High Speed Rail. With the rapid development of China's electrified railways, high-speed railway electrical and electronic equipment is gradually developing towards systematization and integration, and the equipment is resistant to overcurrent. The level is getting lower and lower, which leads to the increasingly serious damage to railway system equipment caused by the intrusion of strong electricity such as lightning and induced overvoltage, which not only causes a large number of primary equipment to burn down, but also causes many secondary equipment damage. Accidents such as the exit of the integrated automation system and the tripping of the network switch have seriously affected the safe and reliable operation of the railway system. In order to solve the problem of strong electricity (including lightning overvoltage and power frequency overvoltage) to the secondary system of railway traction substation Harm, China Railway Corporation issued "Transportation and Supply Equipment Letter [2016] No. 325 "Guiding Opinions on Optimizing Technical Schemes for Preventing Intrusion of Strong Electricity in Secondary Systems of Traction Substations" on September 1, 2016, and in 2017 July 12th Document [2017] No. 240 "Implementation Plan for Optimal Setting of Surge Protectors in Traction Substations".

I. Introduction With the rapid development of modernization construction and the wide application of power electronic technology, the threat posed by lightning is becoming more and more serious. Taking chemical enterprises as an example, there are many towering structures on site, which are easily invaded by lightning in thunderstorm weather Induced lightning current is generated on the internal power cables and signal cables, which is extremely harmful to the normal production of enterprises, and lightning safety protection measures have attracted the attention of users. II. Although chemical companies conduct lightning protection inspections every year in accordance with GB/T 21431-2015 "Technical Specifications for Detection of Lightning Protection Devices in Buildings". However, during the thunderstorm season, the following problems still exist in operation: 1) The communication port of DCS or PLC instrument automation system is easily damaged; 2) The outdoor monitoring system of the tank farm is easily damaged; 3) The inverter is easy to trip. The user system is checked and found that there are still defects in the overall lightning protection comprehensive configuration, mainly including the following points: a) The corrosion of external lightning protection facilities (down conductors) is more serious; b) There are still many unreliable connections in the equipotential connection between the field equipment cabinet shell or passive conductive components, either unconnected or the connection line is loose; c) The on-site lightning protection wiring is unreasonable; d) Symbolic configuration of surge protector.

The 36mm large current and T1-level backup integrated surge protector products have been trial-produced in small batches and can be supplied in batches. Jinli marketing promotion of the technical department is also fully recommended.

The intelligent joint control technology of the inverter and the tracking bracket (SDS intelligent tracking algorithm), combined with the intelligent string inverter, aims to realize the linkage optimization of the inverter and the bracket control, and further improve the additional effect of the tracking bracket. SDS technology can realize the linkage and closed-loop control of the inverter and the tracking bracket control system, and always keep the power station system running in a state with the largest amount of light received by the components and the best power output. And it does not require additional sensing equipment, gets rid of manual and experience dependence, uses AI technology to automatically perceive occlusion and weather change information, and automatically performs tracking angle optimization and control. Currently, it has cooperated with most mainstream bracket manufacturers. "At present, whether it is morning or evening, the phenomenon of blocking the front and rear rows of the power station is basically gone, and the power generation in cloudy and rainy days has increased significantly. Although SDS is only a small-scale application, it has already brought us benefits. "If it is applied to the entire 200MW power station, according to The same increase ratio, excluding subsidies, is conservatively estimated to bring nearly 2 million yuan in revenue. " The application value of high-efficiency modules, inverters and tracking systems has been recognized by end customers, and the application ratio will increase rapidly, but to make the photovoltaic system play a greater potential, simple patchwork is far from enough, and it is impossible to create a future-oriented smart system. Practical application cases have also verified once again that only by coordinating and integrating high-efficiency equipment and making joint optimization, can the efficiency of equipment and systems be maximized, and the power station can generate electricity vigorously throughout its life cycle.

The replacement of products is the law of industry development. People usually pay attention to the performance quality of products, but often ignore the time quality of products, that is, reliability. The introduction of any new product should provide users with the performance quality, time quality and economic indicators of the product. The main methods to improve the reliability of SPD include: a. Manufacturers improve MOV chip designs, adopt new materials and improved processes, and produce products with low failure rates and improve inherent reliability. b. Provide a good environment such as suitable temperature, humidity and air pressure to maintain environmental reliability. c. Screen and age the SPD to shorten the early failure period. d. Replace deteriorating SPDs as appropriate or periodically. e. Select an intelligent SPD and monitoring system capable of life early warning. f. Derating design is the main method to improve SPD reliability. The derating design is to reduce the electrical stress (surge) that the SPD bears. Reasonable derating can greatly reduce the failure rate of the SPD.

Improve the electricity price policy that supports the application of energy storage, the price compensation mechanism for the operation of regulated power sources such as solar thermal power generation and energy storage, and support the construction, integration and development of new energy power. Wind/PV: 1. Improve building renewable energy application standards, encourage building-integrated photovoltaic applications, and support the use of solar energy, geothermal energy and biomass energy to build renewable energy building energy supply systems. 2. Focus on desert, Gobi and desert areas, accelerate the construction of large-scale wind power and photovoltaic power generation bases, upgrade and transform existing coal-fired power units in the region, and explore the establishment of a mechanism for the coordination of transmission and reception of new energy power transmission by both ends, and support New energy power can be built as much as possible, can be combined, and can be developed as much as possible. 3. In rural areas, priority should be given to supporting rooftop distributed photovoltaic power generation and biogas power generation and other biomass power generation to connect to the power grid, and power grid companies should give priority to purchasing their power generation. 4. Encourage the use of land suitable for decentralized development of wind power and photovoltaic power generation in rural areas, and explore the investment and operation model of renewable energy projects with unified planning, decentralized layout, agricultural enterprise cooperation, and benefit sharing. 5. Promote the high-quality development of the energy electronics industry, promote the integration and innovation of information technology and products with clean and low-carbon energy, and accelerate the innovation and upgrading of smart photovoltaics. 6. Strictly standardize the collection of land (sea-related) taxes and fees for energy development. Eligible offshore wind power and other renewable energy projects can apply for a reduction or exemption of sea area usage fees according to regulations. Encourage the promotion and application of land-saving technologies and models in the development and construction of new energy sources such as wind power. 7. Promote the internationalization of standards in fields such as solar power generation and wind power generation. Encourage all regions, industry associations, enterprises, etc. to formulate stricter local standards, industry standards and enterprise standards in accordance with the law

GB and UL product standards for SPD There is a big difference between the products under the UL system and the product standards under the GB system. On the one hand, due to differences in power distribution systems, products require different considerations in design; on the other hand, due to differences in the understanding of the products themselves between the two major standard systems, the UL standard focuses more on the safety testing of the products themselves. , the GB standard focuses more on the performance test of the product itself. As far as SPD product standards are concerned, the national standard adopts the IEC 61643 standard, the standard number is GB / T 18802. 11 - 2020 (hereinafter referred to as "GB standard"), and the SPD standard under UL is UL 1449 CRD / 5- 2014 "Standard" For Safety SurgeProtective Devices" (hereinafter referred to as "UL Standard") Under the two standard systems, there are big differences in SPD. It can be simply summarized into the following 6 more obvious differences: a. UL and GB standards have different SPD product classification rules. UL distinguishes Type 1, Type 2, and Type 3 SPD products according to the installation location of the SPD, whether external protection equipment is required, and whether it is a fixed type. b. UL standard certification is a certification process from component to product. Not only the performance of the final product is certified, but also the raw materials and components of the product are required to comply with UL standards. c. There is no definition of the maximum surge energy in the UL standard; while in the GB standard, the manufacturer of the maximum surge energy can claim its own product performance. In the GB standard, the test waveforms for Type 1 and Type 2 are 10 / 350 μs waveform and 8 / 20 μs waveform respectively; while in the UL standard, the 10 / 350 μs waveform is not defined, whether it is Type 1 or Type 2. Tested with 8 / 20 μs waveform. d. UL standards are more focused on safety: tests such as short circuit and overvoltage are more comprehensive and stricter. e. GB standard focuses more on the performance parameters of lightning protection: surge discharge capability and Up. f. All tests to UL standards are maintained in the original condition of the samples and no modifications to the product are allowed. There is no difference between the two standards, because the test methods are different, and the differences in SPD performance parameters under the GB and UL standards are not comparable.

Depending on the energy used, there are usually thermal power generation, wind power generation, photovoltaic power generation, nuclear power generation, and hydropower generation. Thermal power generation requires 310 grams of coal, 4 liters of purified water, 190 grams of diesel and 59 grams of natural gas to produce 160 grams of carbon dioxide, 272 grams of carbon dust, 6.2 grams of sulfur dioxide, and 15 grams of carbon oxides to generate one kilowatt-hour of electricity; Hydropower is less polluting but only 630 cubic meters of water can generate one kilowatt of electricity; Photovoltaic power generation requires a 500-watt photovoltaic panel to be exposed to the sun for an equivalent time of 2 hours to generate one kilowatt-hour of electricity; Wind power A 2MW fan rotates at a rated speed for 3.5 seconds to generate about 1.94 kWh of electricity, that is, the fan can generate 1 kWh of electricity after half a turn. The effect of one degree of electricity is beyond your imagination! Don't look at the price of a kilowatt-hour electricity is not high, but it can do a lot of things. Countless late nights of overtime work, one desk lamp can accompany you to light up for 40 hours; when you are swiping your mobile phone, one unit will silently support the router to work for 10 days, guaranteeing you continuous high-quality Internet; for you, a foodie, one kWh of electricity runs a 66-watt refrigerator for 15 hours to ensure you eat fresh ingredients. One kilowatt hour of electricity can also support the air conditioner to provide you with 1.5 hours of cooling in hot summer.