35KV New Energy Box Type (Chinese Type) Substation

Overview

35KV compact pre-installed substation, commonly known as the Chinese type box transformer, is a new type of box substation, products are widely used in wind farms and photovoltaic power plants. It is mainly composed of transformer body, high voltage electrical part, low voltage electrical part, box and so on. The transformer is a three-phase double-winding oil-immersed self-cooling power transformer without excitation regulating voltage. The high voltage electrical part of Hua-type box transformer is mainly composed of 35kV high voltage circuit breaker, 35kV isolation switch, 35kV current transformer, 35kV voltage transformer, 35kV lightning arrester, 35kV live display, etc. The low-voltage electrical part of Huashi box transformer is mainly composed of low-voltage frame circuit breaker, self-use electrical system (self-use transformer, feeder switch, etc.), surge protector, etc.

Product characteristics

1, compact structure, small size, easy installation, flexible;
2, fully insulated, fully sealed structure, safe and reliable, maintenance-free, reliable protection of personal safety;
3, the high voltage side adopts double fuse protection, in which the plug-in fuse fuse is double sensitive fuse (temperature, current), the backup fuse is the current limiting fuse, reducing the operating cost;
4, the high-voltage wire adopts the cable connector structure, fully insulated, safe and reliable, easy to operate;
5, can be used for ring network, can also be used for terminal, conversion is very convenient, improve the reliability of power supply;
6, the transformer is three-phase three-column or three-phase five-column structure, the iron core adopts the stepped joint process or rolled core process, low noise, low loss, anti-short circuit and overload ability;
7, the use of vacuum drying and vacuum oiling special process, our company will be used in 110kV products of this process extended to 10kV products, to improve product quality to provide a strong guarantee;
8, the box can use anti-corrosion design and special spray painting treatment according to the requirements of the operating environment, with “three anti-corrosion” function, that is, anti-condensation, anti-salt spray, anti-mold function and can meet the high temperature, high humidity environment anti-corrosion requirements.

Technical requirement

The Chinese type box transformer is composed of three parts: high voltage room, transformer and low voltage room. Each room is separated into an independent interval by a partition board. A lower manhole is provided in the box for easy installation and maintenance. Its internal layout structure is set according to the requirements of standard design drawings. Natural cooling method is adopted in the tank, and the temperature of the low pressure chamber is controlled below 60℃ through the cooling device in the cabinet to ensure a good operating environment of the secondary equipment. On the transformer cabinet, install the communication cabinet (to install the switch, optical fiber box and other devices), UPS battery cabinet in 1.1 times continuous long-term overload operation (the oil temperature does not exceed 85℃ under the project environment), 1.2 times continuous overload operation for 3 hours (the oil temperature does not exceed 85℃ under the project environment), 1.5 times short-term overload operation. It shall comply with the provisions of General Equipment for Transmission and Transformation Engineering of State Grid Corporation (Typical specifications for 66kV and below transformer and distribution power stations) and the relevant values in Table 3-2.

Dehumidification, explosion-proof and anti-condensation measures should be taken inside the transformer box. The cable holes in the high and low pressure chamber should be sealed by using polymer flexible sealing material TS-68 on the basis of fireproof mud sealing. The door of the container is fitted with sealing strips. The sealing strip is made of EPDM rubber, which has good heat resistance, weather resistance, ozone resistance, corrosion resistance and aging resistance. High-voltage cable heads, busbars, wiring terminals and other live parts are fully insulated with flame retardant and thermal conductive silicone rubber insulation material TS-10. The high-voltage parts of 35kV should be able to withstand the requirements of 40.5kV voltage and voltage for 1min after insulation treatment. The low-voltage busbar should be able to withstand the requirement of 2.5kV voltage and withstand voltage for 1min after insulation treatment. High voltage bushing porcelain bottles, insulation rod, insulator and other insulation devices are brushed with high self-cleaning anti-fouling flash coating SRTV, coating thickness 0.4±0.1mm. The seller is responsible for retrofitting the added cooling fan with external circulation ventilation. (Delete) The design service life of the box shall not be less than 30 years. The combination of low-power constant heater and dehumidifier should be set up in each compartment, and ventilation holes should be set reasonably according to the volume of the cabinet. The temperature and humidity signals of the box should have the remote transmission function and be uploaded to the box transformer measurement and control device through the communication interface.