Continuous Operation Control of PMSM with Compressor Loads of Air Conditioners in Case of DC Power Supply Loss

Abstract

The interruption of power supply is one of the major technical issues in rotation angle sensorless controls of PMSMs. This causes failures of inverter operation due to voltage drop in filter capacitor (FC). In order to solve this technical issue, we propose a method to achieve continuous operation of PMSMs with low inertia loads, for example compressors of air conditioners, in case of power supply interruption. In the proposed method, the current reference is determined according to the relationship between the kinetic energy of the motor and the electrical energy of the FC to effectively use the available energy. The proposed method is validated by experimental test of 1-kW class PMSM.