Two-stage power control method of rotary power flow controller for flexible interconnection of distribution network

Abstract

With the rapid development of active distribution network construction, flexible interconnected distribution networks have become the mainstream power supply structure. To ensure the safe power supply of the distribution system, power control methods suitable for flexible interconnected distribution networks should be further studied. The electromagnetic rotating power flow controller (RPFC) is a feasible solution for power control in distribution networks. This paper first constructs an RPFC steady-state power decoupling control model based on instantaneous reactive power theory. However, it is difficult to achieve stable power control due to the difficulty of coordinated control of the rotor position angle of the rotating phase transfer transformer. On this basis, the servo motor's two-stage speed control and speed coordination scheme are used to achieve stable and error-free control of the two rotor angles, meeting the power regulation requirements of high precision, high reliability, and fast response. A 380 V/40 kVA RPFC prototype and experimental platform were developed, and power regulation and power equalization experiments were conducted. The results indicate that the proposed control scheme can regulate at the second level. Control accuracy is maintained within 4%, showing good dynamic and static performance. This meets the requirements for flexible closed-loop operation in the interconnected distribution network.