The world's first photovoltaic intelligent double-layer double-common box transformer was successfully developed

On the morning of September 3, 2021, the factory acceptance ceremony of the world's first "photovoltaic intelligent double-layer double-common box-type transformer" successfully developed by Guangzhou Haizhu Power Supply Bureau and Haihong Electric Co., Ltd. was held at the Haihong Electric headquarters. Guangdong Power Grid Corporation Guangzhou Power Supply Bureau Infrastructure Department, Guangzhou Power Supply Bureau Biotechnology Department, Guangzhou Haizhu Power Supply Bureau, Guangzhou Electric Power Engineering Design Institute, Cuishan Lake High-tech Zone and other relevant leaders and R&D personnel came to the site of the factory acceptance ceremony to witness this historical moment.

The world's first photovoltaic intelligent double-layer box-type substation, green and low-carbon smart integration to create excellent products

With the rapid development of urbanization, under the background of the power grid construction environment of "three highs and one limit" (high load density, high power supply reliability, high power quality demand, and limited land), the electricity load in urban villages in Guangzhou However, the construction of urban villages has two major problems: difficulty in site selection and land use. In order to solve the problem of power consumption in urban villages, Guangzhou Haizhu Power Supply Bureau made full use of the vertical space of the relevant site, cooperated with the industry pioneer Haihong Electric Co., Ltd. to carry out research and development, and creatively developed The world's first intelligent low-carbon, green and environmentally friendly photovoltaic intelligent double-layer double-common box transformer. This innovative product has the advantages of compactness, intelligence, visualization, and low carbonization, and provides an optimal solution for connecting the "last mile" of electricity consumption in urban villages。

The box-type substation is located in Chengzhong Village, Haizhu District, Guangzhou City. Due to the large flow of people and vehicles and the large number of pipelines, it is difficult to coordinate pipeline construction. The distribution transformer in the original station area is overloaded, but there is a lack of land for the construction of power facilities. The original project plan is a two-story power distribution room, equipped with two 800kVA dry transformers (length 10.88m x width 4.13m x height 7.5m, occupying an area of about 44.93m²), due to the area occupied by the power room The area is large, and at the same time it blocks the sunlight of the residents, which is strongly obstructed. Guangzhou Haizhu BureauThe urban village is a demonstration site, combined with Haihong's innovative plan, the project is changed to adopt the world's first photovoltaic intelligent double-layer double-communication box transformer (5.3 m long x 1.7 m wide x 2.9 m high, covering an area of 9 m< sup>2), compared with the double-storey electric house, the floor area is reduced by 80%, the height is reduced by 61%, and the civil construction investment is reduced by 90%, and the project plan has been unanimously approved.

Photovoltaic intelligent double-layer double public transformer box change

The photovoltaic intelligent double-deck double public transformer box substation project adopts the domestic advanced 3D BIM design technology, the visualized 3D model guides production, improves product quality, shortens the production period, and realizes a compact layout plan.

The box transformer is divided into upper and lower two-layer structure. The upper layer is a green energy-saving three-dimensional wound core open-type dry-type transformer, which has three-phase balance, low loss, strong overload capacity, low noise, fire and explosion-proof, moisture-proof and dust-proof, small partial discharge, and surrounding electric field Low magnetic field strength, strong short-circuit resistance, small size, light weight, easy maintenance and so on. Optimally configure 4 medium-voltage ring network cabinets, and configure 9 low-voltage cabinets, 1 DTU, 1 photovoltaic grid-connected photovoltaic metering cabinet, and 1 control cabinet on the lower floor, with all the functions of the double-layer electric room.

A photovoltaic power generation system is installed on the top of the box substation, in response to the national double carbon target policy, to achieve "carbon neutrality" for secondary equipment.

The box-type substation responds to the call for digital grid construction, integrates the V3.0 intelligent equipment of the South Grid and the noise and radiation monitoring device, and monitors the environment, security, equipment status, and electrical protection system in real time online to realize the "observable, measurable, and controllable" digital grid. " requirements. Make the power grid more secure, reliable, green, efficient and intelligent.

• Green and low carbon, energy saving and environmental protection

The box substation adopts an open three-dimensional wound core dry-type transformer, which meets the advantages of "safety, environmental protection, energy saving, and tranquility".

The project adopts two 800kVA high-efficiency energy-saving open dry transformers. Compared with the traditional three-level energy-efficient transformer with the same capacity, the two dry transformers can save about 18,000 yuan in electricity bills per year, which is equivalent to reducing carbon dioxide emissions by about 24 tons, and its carbon reduction value is about 1,000 yuan. The total economic benefits of energy saving and carbon reduction can reach 19,000 yuan per year, helping the country achieve the "double carbon" goal.

Adopt high-quality "power generation glass": the "power generation glass" made of cadmium telluride (CdTe) thin-film solar cells is better than the current monocrystalline silicon power generation components in terms of service life, power generation, safety and maintenance costs. .

Photovoltaic grid-connected operation to meet the electricity demand of secondary equipment: installed capacity of 1350Wp, photovoltaic power grid-connected operation, annual power generation of about 1400kW h (degrees), and annual loss value of secondary equipment (about 1260kW h) reached Carbon neutral.

• Intelligent O&M, Visible and Sensible

The deep integration of CSG V3.0 smart devices and box-type transformers helps the construction of digital power grids.

Realize the real-time online monitoring of the box substation environment, security, equipment status, electrical protection system, fault warning, big data analysis and other functions, which can effectively reduce the accident rate and make maintenance safer and more convenient.

An embedded touch screen is installed, and all sensor data can be displayed by loading the cloud platform system, such as real-time monitoring of transformer noise, radiation, etc., reflecting the advantages of environmentally friendly electrical equipment. Install a fingerprint password access control system to improve the security level of the equipment.

• Safe and reliable, ingeniously built

(a)Double-layer design to reduce the risk of flooding

The transformer is placed on the second floor, which effectively reduces the risk of transformer flooding due to urban waterlogging or flood disasters. The transformer adopts an open dry transformer, which has a good waterproof effect. luck status.

(b)Interconnection of dry transformers to improve power supply reliability

The two open dry transformers are connected to each other. If one of the transformers fails, the other transformer can supply power through the contact switch to improve the reliability of power supply.

(c)Carefully combined to improve the fire rating

• The open dry transformer adopts the insulation system composed of DuPont NOMEX^® aramid insulating paper, PIF polyimide film and German Elantas one-component environmentally friendly insulating varnish. High-quality R(C) grade electrical insulation material, with good electrical insulation and mechanical properties and high insulation and heat resistance level, fireproof and explosion-proof, flame retardant and self-extinguishing. The overall combustible content is low. Compared with traditional epoxy resin dry conversion, the weight of open dry variable combustibles is reduced by more than 85%.

• Pie coil, low electric field strength, overall vacuum pressure impregnation, partial discharge can be less than 5pC.

• Separate compartment design for two transformers, high-voltage cabinet room and low-voltage cabinet room are also compartment design。

• High-strength stainless steel shell, powerful fire protection system

(d)Prefabricated from the factory to ensure stable performance

The products are pre-installed in the factory, one step in place, ensuring the stability of the overall performance of the box-type substation, and effectively reducing the problems caused by the secondary installation of products on site.

• Easy to operate and easy to maintain

(a)The box transformer adopts full-open door type, which is convenient for installation, operation and maintenance.

(b)All the switches that need to be operated are located on the front (convenient operation position), making maintenance more convenient.

(c)The low-voltage frame circuit breaker adopts the exposed design of the operating handle, which can be directly operated by opening the outer box door.

(d)Combined with the double-layer layout structure, it is equipped with a folding operation ladder, which makes maintenance and operation safer.

(e)Fully insulated high-voltage cabinets are maintenance-free.

(f)Open ventilated dry-type transformer is easy for maintenance.

(g)Stainless steel shell + imported car paint, no rust, low maintenance cost.

   

Photovoltaic smart double-deck double-compartment box-substation integrates a number of smart low-carbon innovations
   

Leaders and experts present at the ceremony highly recognized the photovoltaic intelligent double-layer double-common transformer box substation, and believed that the double-layer box substation excellence project is a good attempt by Guangdong Power Grid to respond to "carbon peaking and carbon neutrality". Under certain circumstances, the goal of green, low-carbon, and intelligent operation and maintenance has been achieved, and it can be widely used in urban villages where land for power construction is scarce. Guangzhou is comprehensively deepening urban renewal, promoting the realization of new vitality in old cities, and the transformation of urban villages is the top priority. Photovoltaic intelligent double-deck double-communication transformer box has the advantages of small footprint, intelligent operation and maintenance, green and low carbon It will surely become a powerful weapon to solve the problem of electricity shortage in urban villages. Next, Guangzhou Haizhu Power Supply Bureau will further develop intelligent and low-carbon integrated innovative solutions with Haihong Electric Co., Ltd. through the establishment of scientific and technological projects, continue to transform and upgrade processes and technologies, and contribute to the realization of the goal of "carbon neutrality" strength.

In the face of major changes unseen in a century, the party and the government have a long-term perspective and assess the situation. The Party Central Committee with Comrade Xi Jinping at the core proposed the "dual carbon" goal, which is a leading and systematic key guide for my country's green and low-carbon development. Facing the new requirements under the new situation, Haihong Electric Co., Ltd. has always insisted on R&D and innovation since its establishment in 1998. With the world-leading three-dimensional wound core technology, it has obtained more than 250 patents at home and abroad, of which more than 50 are invention patents. At present, it has five major research and development teams: product research and development, tooling and mould, equipment manufacturing, material research, and testing and testing. It has won many provincial and municipal scientific and technological progress awards, and participated in the formulation and release of nearly 30 national/industry standards. Haihong Electric has always mastered With the core technology of three-dimensional wound core transformer, the patented technology has won the recognition of domestic and foreign counterparts, and reached 6 technology licensing projects with our company. Haihong Electric allows China's advanced equipment to be displayed abroad, and has truly made "world technology, win glory for the country".

   

The integration of party building witnessed the success of the research and development of photovoltaic intelligent double-layer double-common transformer
   

In the future, Haihong Electric will continue to increase investment in technology research and development, accelerate the transformation of scientific and technological achievements, meet market demand, study various professional scenarios, refine innovative products with ingenuity, bloom technological innovation strength, and provide customers with more energy-saving, environmentally friendly, safe and reliable, Intelligent low-carbon high-quality products and comprehensive solutions, practice Haihong's "initial heart" and "mission", and contribute Haihong's solutions and wisdom to the country's carbon reduction, green, and environmental protection!