Modelling and Experimental Validation of Interharmonic Emission of an Inverter-Driven Heat-pump

Interharmonic modelling and experimental verification of an inverter-driven heat-pump (HP) under different power levels is considered in this paper. Results of a research activity, conducted first in New Zealand at the University of Canterbury (UC) and then in Italy at the University of Campania (UCLV), are reported. The aim is to examine the effect of interharmonics on the low voltage network produced by HPs. The time-domain model developed in another paper from some of the authors for harmonic studies and experimentally validated by measurements made in the field is here extended to model also interharmonics. Very accurate results in terms of interharmonic injection are obtained, which will allow the use of the proposed model in more comprehensive harmonic and interharmonic penetration studies in the time and frequency domains.