Zero-sequence-current suppressing winding open type permanent magnet synchronous motor vector control method

Abstract

The invention discloses a zero-sequence-current suppressing winding open type permanent magnet synchronous motor (PMSM) vector control method, belonging to the motor control field. The zero-sequence-current suppressing winding open type permanent magnet synchronous motor vector control method is characterized in that a winding neutral point of the PMSM is opened; 6 output terminals are introducedto connect two output terminals of two-level inverters; each of the two two-level inverters is provided with one zero vector and 7 effective voltage vectors, so as to form 6 sectors; and a decouplingSVPWM control module which can suppress the zero sequence current distributes voltage commands to the two two-level inverters according to the principle that the size is the same and the direction isreverse, determines and demodulates the sectors in which the voltage vectors exist according to the size of the rotor position angle, and finally calculates the operating time of the effective voltagevectors and the zero vector of each sector, so that the zero sequence voltage generated from the zero vector can be used to offset or weaken the zero sequence voltage which is generated when the effect vectors are synthesized so as to suppress the zero sequence current and improve the utilization rate of voltage.

Description

technical field [0001] The invention belongs to the field of motor control, and in particular relates to a vector control method of an open-winding permanent magnet synchronous motor, which suppresses the zero-sequence current of a motor drive system, and is particularly suitable for electric vehicles and other application occasions requiring wide speed regulation. Background technique [0002] Vehicle drive motor is one of the key executive components of electric vehicles, and its driving performance directly affects the overall performance of electric vehicles. Vehicle drive motors mainly use built-in rare earth permanent magnet synchronous motors, which have the advantages of high efficiency and high power density. However, the permanent magnet synchronous motor is limited by the constant air gap magnetic field and the limited inverter capacity, and the speed regulation range of the motor is limited. It is limited in the operating occasions such as electric vehicles that ...

AI Technical Summary

Problems solved by technology

However, independent power supply requires more hardware cost and larger volume, which does not meet the requirements of compact layout, low cost and high performance of electric vehicles

The open-winding topology has two sets of inverters, which is equivalent to a three-level inverter, so the traditional single-inverter two-level space vector modulation technology is not applicable in the open-winding topology

And when the permanent magnet synchronous motor adopts vector control, the inverter will generate zero-sequence voltage, resulting in zero-sequence current in the winding of the open-winding motor, affecting the stability and operating efficiency of the motor

The motor system disclosed in the Chinese Patent Application No. 201410145310.2 uses a three-level SPWM control algorithm. Considering the influence of the zero-sequence current of the system, a proportional resonant controller is used to suppress the zero-sequence current, but the inverter voltage output capacity of the algorithm Not fully utilized, low voltage utilization

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