Extended constant power speed range of the permanent magnet synchronous machine driven by dual mode inverter control

The scope of this work is the Permanent Synchronous Machine (PMSM) operating at Constant Power Speed Range (CPSR). The proposed technique to drive the PMSM at CPSR is the Dual Mode Inverter Control (DMIC). The main idea behind DMIC is to change the three-phase operation of the PMSM below base speed to single-phase above base speed. This technique allows driving the PMSM in a wide CPSR. The DMIC uses three facts to achieve wide CPSR. First, it introduces the idea of the advance angle, which allows driving current into the machine while the back-emf is smaller than the DC link voltage. Second, the blanking angle, which is used to maximize electrical to mechanical power conversion by increasing the on time of the transistors of the Voltage-Fed Inverter (VFI) and therefore slowing down the decreasing in the outgoing phase. Finally, this technique avoids regeneration through the bypass diodes by introducing an ac-voltage controller interfacing the VFI and the PMSM This paper presents the inverter topology and the firing scheme of the DMIC and shows simulations results of the PMSM operating in high speed.