To realize the grid-connected and transient real-time simulation of doubly-fed wind power systems, a multi-rate parallel real-time simulation method based on a field programmable gate array (FPGA) and CPU co-simulation is studied. The switch function method is used to model and optimize the resources of the back-to-back converters in the doubly-fed wind power system, and the model partitioning between systems with different step lengths is carried out based on the PWM homogenization principle. Using the advantage of the high running rate of the FPGA, a small-step simulation of the "back-to-back" converter is realized with 200 ns step size. To meet the demands of real-time simulation of an active power distribution network, the 200 ns/50 parallel co-simulation of the FPGA and a self-developed universal real-time experimental platform (UREP) is realized. By comparing with Simulink offline simulation results and analyzing the FPGA resource consumption before and after model optimization, the real-time and accuracy of co-simulation is verified. This can provide a technical reference for the grid connection and transient study of various wind power systems.

This work is supported by the National Natural Science Foundation of China (No. 51867007).