Research on Application of Low Voltage Ride Through Technology of Auxiliary Equipment Inverter of Thermal Power Plant in Power Grid

To prevent cascading failures caused by abnormal frequency and voltage of AC/DC hybrid power grids, carry out the low voltage ride-through transformation of type I auxiliary equipment to ensure that the power plant auxiliary equipment of the power plant has low voltage ride through under 20%, 60% and 90% of the rated voltage ability. In order to improve the adaptability of the low voltage ride-through equipment in the voltage support process, a three-phase uncontrolled rectifier bridge and a Boost Boost circuit are built with diodes as the original rectifier bridge. In view of the tripping of the low-through device under some working conditions in the field test, the parameters of the rectifier circuit and the Boost Boost control system were improved and adjusted, and a buffer circuit was added. MATLAB simulation results show that, under different working conditions, the circuit after coefficient adjustment has a lower oscillation peak.