New Three-Phase Current Reconstruction for PMSM Drive with Hybrid Space Vector Pulsewidth Modulation Technique

Current sensing techniques with reduced number of sensors attract a high interest from industry, for the possibility of cost reduction and sampling mismatch reduction. This article puts forward a new single current sensor (SCS) method for a permanent magnet synchronous motor three-phase current reconstruction, with a novel hybrid pulsewidth modulation (PWM) technique introduced. This method is implemented by changing the position of SCS from dc bus to a current branch, and a modified space vector PWM technique is employed to realize the phase current reconstruction. Compared with traditional SCS control methods, the proposed method can relieve the measurement dead-zones at sector boundary region without introducing extra compensation algorithms. Besides, this method can be realized not only with a single hall-effect current sensor but also a single shunt resistor, which further expands the applications and increases the system reliability as well. This method is also available in other motor control with a two-level three-phase PWM voltage source inverter topology. The accuracy and feasibility of the proposed method is validated by the simulation and experimental results.