Implementing Grid Supportive Behavior in Induction Motor-Driven Loads Using Field Oriented Control

This paper presents and validates the controllers developed to implement grid-supportive behavior in inverter-based loads. Inspired by a recently proposed grid-supportive load (GSL) model, the controllers combine the GSL model with field-oriented control of induction motors to demonstrate that the proposed GSL behavior can be implemented in inverter-based appliances using local measurements. The control algorithm is developed and validated in MATLAB/SIMULINK for loads that satisfy two affinity laws: the load torque is constant, and the load torque is proportional to the square of angular speed. The results show that motor-based loads can follow the locally measured frequency and respond fast to provide primary frequency response to the power system. This capability can help in integrating more variable renewable energy without requiring, or reducing, the need for reserving headroom in renewable power plants to provide frequency response.