Hardware in-the-loop simulation system based on NI-PXI for operation and control of microgrid

This paper proposes a hardware in the loop simulation (HILS) system based on NI-PXI to test the microgrid operation and control. The HILS system is composed of a NI-PXI real-time digital simulation platform for running the real-time simulation model, a NI compactRIO which used as a controller of microgrid, and a PC for running the human-machine interaction interface and giving the control instructions. A coordinated control strategy of energy storage and controllable load is designed for microgrid grid-connected operation and islanded operation. This microgrid includes a doubly-fed induction generator (DFIG), a battery energy storage system (BESS) and a desalination load. In grid-connected mode, the coordinated control can ensure the exchange power between microgrid and grid is a fixed value. In islanded mode, it can stabilize frequency and voltages. The test results show the feasibility of the hardware in the loop simulation system and the proposed coordinated control strategy.