Aug 01, 2020
In view of the characteristics of the wind power generation system, a PWM inverter control system connected in parallel with the grid is designed. The system adopts current instantaneous value feedback control, and directly uses the grid voltage synchronization signal as the inverter output current tracking command. Closed-loop follow-up control realizes feeding electric energy to the grid with unit power factor. The stability of the system is analyzed, and the experimental results prove the feasibility and correctness of the inverter control system.
With the strengthening of environmental protection awareness and the demand for renewable energy, wind power technology has received increasing attention. Due to the instability and randomness of wind energy, the electrical energy generated by wind turbines is alternating current with random changes in voltage and frequency. Effective power conversion measures must be taken before wind power can be sent to the grid. In order to improve the operating performance of wind turbine power generation systems, variable-speed wind power generation systems based on AC-DC-AC converters have been developed in recent years.
In the AC-DC-AC variable-speed wind power generation system, the control technology of the inverter is the key, and research work in this area has been launched at home and abroad. Literature  ~ Literature  have specialized research on this. This article combines the advantages of inverters in the above documents and proposes a new inverter control scheme. The inverter directly uses the grid voltage synchronization signal as the tracking signal of the inverter output current, so that the output current can quickly track the grid voltage. The control system has a simple structure, and the test results show that the control system can achieve unity power factor output, and the output current has low harmonic content.