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In some key areas, fault-tolerant control is usually needed in order to enable the motor to operate continuously in fault mode. Given that it is difficult to detect the zero-sequence current of the open winding permanent magnet synchronous motor after the phase break fault occurs, the traditional zero-sequence current suppression strategy is no longer applicable after the phase break fault occurs. Therefore, a zero-sequence current suppression strategy for a common DC bus under a phase break fault is proposed in this paper. By establishing the mathematical model between the current component in the synchronous coordinate system and the current component and the zero-sequence current in the static coordinate system, the relationship between the non-fault phase current and the zero-sequence current in the open phase fault is analyzed. A method of suppressing the zero-sequence current by using proportional integral double resonance in a zero-sequence current control loop is proposed. In addition, according to the large number of calculations in traditional space vector modulation (SVPWM)—such as sector judgment and coordinate transformation—a decoupling modulation algorithm is proposed to modulate the reference voltage vector. Finally, the experimental platform for the common DC bus open winding permanent magnet synchronous motor is built, and the zero-sequence current suppression method for the common DC bus OW-PMSM under phase break fault is verified experimentally. [ABSTRACT FROM AUTHOR]

In open‐winding permanent magnet synchronous machine (OW‐PMSM) applied in electric vehicular system, two voltage sources composed of battery packs are applied. For safety and better performance, the over‐discharge on one of these two voltage sources should be avoided and their state of charges (SOCs) should be controlled in balance. On this basis, a reference voltage redistribution‐based control scheme is proposed to balance the SOCs of OW‐PMSM system in this letter, which utilizes the SOCs of the two voltage sources to distribute the reference voltages into two inverters. With the proposed method, the SOCs of the two voltage sources can be controlled in balance dynamically, while the synthesis of the reference voltage is not affected. The performance of the proposed method is validated experimentally. [ABSTRACT FROM AUTHOR]

The open‐winding permanent magnet synchronous machine (OW‐PMSM) system is widely investigated for its potential fault tolerance while extra switching loss is inevitable due to the doubled switch devices. Hence, to further improve its performance, a fault‐tolerant control strategy against the inverter‐based fault, in which the corresponding terminal of the phase winding is connected with the mid‐point of the two capacitances in parallel to the dc voltage, is proposed in this Letter. In the proposed method, the reference voltages are modulated under the three‐phase stationary coordinate system, considering the voltage fluctuation of the capacitances. In addition, to reduce the switching frequency, the reference voltages are adjusted synchronously, according to the polarity of the reference voltages. Moreover, the effective modulation range of the proposed method is analysed. Finally, the performance of the proposed strategy is validated experimentally. [ABSTRACT FROM AUTHOR]