Hardware-in-the-Loop Testing of Dynamic Grid Voltages for Static Var Compensator Controllers With Single-Phase Induction Motor Loads

This paper investigates the interaction between two Static var Compensators (SVCs) to verify dynamic grid voltage support is maintained and that the SVC controllers do not negatively interact with each other. For this purpose, the controls of the SVCs with all of the remotely controlled Mechanically-Switched Capacitors (MSCs) have been tested in a closed-loop real-time simulator environment using SVC replicas (physical controllers) of the actual field installations. To accurately capture the power system's response to phenomenon such as potential Fault Induced Delayed Voltage Recovery (FIDVR), the dynamics of the generators and the motor loads are modeled in the simulations. A hybrid model consisting of real and reactive power (P-Q) loads and aggregated motor load of a single-phase induction motor suitable for three-phase time-domain simulation was developed and connected to the power system. The developed aggregate motor load model includes details such as the main winding, auxiliary winding, starting capacitor, motor inertia, and distribution transformers. It is observed that dynamic grid voltage support can be maintained and the SVC controllers do not negatively interact with each other if all the SVC control blocks are enabled and function normally.