Electrical Load Emulation using Power Electronic Converters

The paper presents a method of emulating electrical loads using power electronic converters. The loads include machines such as induction motors and its associated mechanical load and also more complex machine systems such as wind power generation systems. The load emulator is effectively a dynamically controllable source or sink which is capable of bidirectional power exchange with either a grid or another power electronic converter system. Using load emulation, the feasibility of connecting a particular load to a grid under various conditions can be studied in the absence of any electromechanical machinery. This paper considers the case of a power electronic Voltage Source Inverter (VSI) emulating a three phase induction motor connected to a three phase ac grid. The VSI is operated in a mode where the current drawn from the ac grid is controlled by closed loop control. Experimental results have been provided to verify the scheme.