Research on Control Strategies of an Open-End Winding Permanent Magnet Synchronous Driving Motor (OW-PMSM)-Equipped Dual Inverter with a Switchable Winding Mode for Electric Vehicles

Abstract

An open-end winding permanent magnet synchronous motor (PMSM) has a larger range of speed regulation than normal PMSM with the same DC voltage, and the control method is more flexible. It can also manage energy distribution between two power sources without a DC/DC converter. This paper aims at an electric vehicle equipped with OW-PMSM drive system with dual power sources and dual inverters; based on analyzing the external characteristics of each winding mode, we propose a winding mode switching strategy whose torque saturation judgmental algorithm, which is insensitive to motor's parameters, could automatically realize upswitching of the winding mode. The proposed multi-level current hysteresis modulation algorithm could set the major power source and switch it at any time in independent mode, which accomplishes energy distribution between two power sources; its two control methods, low switching frequency method and high power difference method, could achieve different energy distribution effects. Simulation results confirm the validity and effectiveness of the winding mode switching strategy and current modulation method. They also show that an electric vehicle under the proposed control methods has better efficiency than one equipped with a traditional OW-PMSM drive system under traditional control.Control strategies of OW-PMSM and dual inverters have always been a research focus. Winding topology and configurations are widely discussed in order to optimize the motor's working range and efficiency [17][18][19]. and zero-sequence voltage elimination method [23,24] are also under extensive research. Loncarski, J. et al. compared the output current ripple in single and dual inverter motor drives for electric vehicles, concluding that the dual-2L inverter can act as a 3L inverter and offers a significant ripple reduction [2], which can also be observed in this paper. AnQun-tao, Sun Li et al. proposed a dual inverters SVPWM modulation method for current control and in this way voltage vector synthesized in the range of a hexagon and when the bus voltage remains constant, the base speed of the electric motor could be 1.7 times that in Y-connection without generating zero-sequence voltage [7,8]. Zhan H., Heng N. et al. studied a common DC bus-based dual inverters SVPWM modulation strategy. In this way, the amplitude of the voltage vector could be maximized and at the same time a zero-sequence current could be suppressed [23,24]. Welchko studied dual sources-based dual inverters' voltage vectors distribution, and proposed three types of voltage distribution methods to adapt to different working conditions of hybrid vehicles to achieve energy management functions between two power sources [16]. However, the two inverters work independently without coordination, and thus the switching frequency of inverter devices has also doubled, which increases the inverter switching loss. All the studies discussed above have proposed current control methods of dual inverters but division of OW-PMSM winding modes and winding modes ...

Torque Ripple Minimization of the Permanent Magnet Synchronous Machine by Modulation of the Phase Currents

“…It should be noted that the injection of 3rd integer multiplier harmonics (triplen harmonics) is not possible in PMSMs driven by conventional three-leg (see Figure 1a) inverters when the phase windings of the machine are arranged in a star connection. On the other hand, due to the decreasing cost of electronic power switches, the six-leg inverters are now an interesting alternative to three-leg systems in terms of increased reliability [11][12][13]. The application of knowledge from the literature regarding the dual-fed open-ended winding PMSM (see Figure 1b) enables the development of new, more effective methods for improving the energy conversion quality in electrical machines (by modulating the phase currents by higher harmonics and, in particular, by injecting zero-sequence harmonics).…”

Research on a Sliding Mode Vector Control System Based on Collaborative Optimization of an Axial Flux Permanent Magnet Synchronous Motor for an Electric Vehicle

“…In electric vehicle applications, Zhao et al [12] researches an axial flux permanent magnet synchronous motor (AFPMSM) with radially sliding permanent magnets (PMs) to fulfill field-weakening control, which is very satisfying for EV drive application. The authors of [13,14] improve the efficiency of electric vehicle systems by optimizing motor design. The authors of [13] propose a driving-scenario oriented optimal design of an axial-flux permanent magnet (AFPM) motor for an electric vehicle.…”

“…The final result shows that the electric vehicle driven by the proposed AFPM motor consumes about 15% less energy than motors designed using traditional methods. The authors of [14] research control strategies of an open-end winding permanent magnet synchronous driving motor equipped dual inverter with a switchable winding mode for electric vehicles, which has better efficiency than one equipped with a traditional OW-PMSM drive system under traditional control. The authors of [15] proposes a new AFPMSM precision torque control method, an effective method to achieve accurate and efficient torque control of an interior permanent magnet synchronous motor (IPMSM) in electric vehicles, based on low-resolution Hall-effect sensors.…”

A Torque Error Compensation Algorithm for Surface Mounted Permanent Magnet Synchronous Machines with Respect to Magnet Temperature Variations

“…Permanent magnet synchronous machines (PMSMs) have been widely used in various applications is sectors such as the aerospace and automotive industry due to their high power density and efficiency [1][2][3]. PMSMs can be divided into two types depending on their rotor structure, which are surface mounted PMSMs (SPMSMs) and interior PMSMs (IPMSMs).…”