Black Box Simulation Approach to Predict the Harmonic Currents in a Heat Pump Unit

This paper investigates the circuit simulation methods to predict the harmonic current emissions from a three-phase heat pump outdoor unit from the impedance measurements and the power consumed by the compressor. The method involves measuring impedance at the input and output of the device with an impedance analyzer. A lumped element equivalent circuit along with parasitic elements is extracted from each measurement for an accurate representation of the simulated system.The new proposed simulation method (black box modeling) and the state-of-the-art simulation method (white box modeling) are verified against the measurementsFurther, the effect of the EMI filter components intended for conducted emissions from 150 kHz to 30 MHz on the harmonic currents is examined.The simulation model is realized in the Simulink environment. The post-processing of the time domain simulated result into the frequency domain to obtain the harmonics is performed in the MATLAB environment.