Introduction  "Energy saving and emission reduction" is the national technical requirement for industrial projects in recent years, and the frequency conversion technology can make process equipment adjust output under different working conditions, thereby saving resources. However, frequency converters are power electronic devices, and the failure rate of IGBT components is relatively high, and the requirements for the operating environment are harsh. Therefore, it is very important to improve the safety and operational reliability of high-voltage frequency converters.

  Method  In the case of failure of individual power units of the high-voltage frequency converter, according to the neutral point drift technology, the position of the neutral point and the angle between the three-phase voltages are adjusted, so that the high-voltage frequency converter can bypass some faulty power units can still operate normally; Send the real-time status of the high-voltage inverter to the DCS, and realize the automatic bypass technology of the high-voltage inverter according to the logic configuration of the DCS; Set up a separate high-voltage inverter room to provide a relatively good operating environment for high-voltage inverters through air conditioning, ventilation, and air duct systems.

  Result  After adopting the internal strategy and external environment strategy for the high-voltage inverter, the failure rate of the high-voltage inverter is reduced, and the safe operation time of the high-voltage inverter is prolonged.

  Conclusion  The use of neutral point drift technology and the automatic bypass technology of the whole machine can reduce the failure probability and frequency of high-voltage inverters, and jointly improve the temperature and humidity conditions of the operating environment, which can increase the continuous and reliable operation time of the inverter, to greatly improve the safety and operation reliability of inverters.