Application of inverter power supply in substation

The reliability of the power control system is the guarantee for the reliable and efficient operation of the power system and equipment, and the power control system must have a safe and reliable control power supply. In the power system, in order to ensure that the backend machine, substation RTU, communication equipment, etc. of the substation can work uninterruptedly after the AC power outage, the engineering practice generally adopts UPS power supply as the main solution, but UPS power supply has the disadvantages of small capacity, high price, high failure rate, and large maintenance. Therefore, the comprehensive automation substation can use power sine wave inverter power supply to replace the conventional uninterruptible UPS power supply, and its advantages are as follows:

1 Reduced system operation and maintenance costs

In the currently operating integrated automation substation, there is generally a background monitoring microcomputer, and the communication equipment is mostly microwave and optical fiber machines. The working
power supply of such monitoring and communication equipment is AC power. To achieve uninterrupted power supply and meet the "four remote" requirements, different equipment must be equipped with uninterruptible power supplies (UPS) and battery packs separately. The inverter power supply installed in the substation can directly use the large-capacity battery of the DC power system used to provide AC power, which saves investment costs compared to the UPS power supply solution, avoids repeated investment in battery packs, reduces maintenance workload, and reduces operating costs.

2 Improved power supply reliability

The DC power supply system installed in the substation has high reliability and long service life. Therefore, the "DC power + inverter power supply" solution is adopted. The monitoring function of the DC power supply system and the communication function of the inverter power supply can be used to remotely monitor the operating status of the inverter power supply in real time, solving the problem that the conventional UPS power supply has small battery capacity, no monitoring, and is prone to battery damage and cannot be discovered in time. Due to the large capacity of the battery in the DC power supply system of the substation, the uninterrupted power supply time is greatly extended after the power grid is cut off, which truly plays the role of a security power supply and improves its power supply reliability.

3 Improved power supply safety

The electric power sine wave inverter is a new generation of DC/AC power supply products. The input is 220V direct current and the output is 220V, 50Hz sine wave alternating current. The input and output ends are completely isolated from the mains, avoiding the impact of mains fluctuations on the load. It fully meets
the requirements of substation RTU, communication equipment, microcomputers and other equipment for working power. It is completely isolated from the mains, and can also avoid power board burning accidents caused by overvoltage such as lightning, thereby improving the safety of the load.

Due to the ultra-isolated output, super anti-interference ability and powerful communication function of the new generation of DC/AC electric sine wave inverter power supply, the "DC power + inverter power supply" solution is adopted in the rural comprehensive automation substation, which has better operation economy, reliability and safety, and truly realizes the unattended monitoring requirements of the equipment working power supply.