Finite-control-set model predictive current control method of five-phase permanent-magnet synchronous motor

Abstract

The invention discloses a finite-control-set model predictive current control method of a five-phase permanent-magnet synchronous motor. The finite-control-set model predictive current control method comprises the steps of respectively mapping a voltage, a current and magnetic flux of the five-phase permanent-magnet synchronous motor under a natural coordinate system to two orthogonal rotating coordinate systems of d1-q1 and d3-q3 according to extended Park rotation transform; constructing an input voltage vector control set which is used in an FCS-MPCC (Finite-Control-Set Model Predictive Current Control) algorithm again; solving amplitude of U<'> of the (d1-q1) coordinate system and an acting time allocation proportion of two basic voltage vectors required for forming a virtual vector; constructing a target function in the FCS-MPCC algorithm of the five-phase permanent-magnet synchronous motor; selecting the virtual voltage vector which enables the target function to be minimum as control output quantity; and performing steps of pulse sequence generation and design on the virtual voltage vector. By the finite-control-set model predictive current control method, a low-order harmonic component of a five-phase motor current caused by a harmonic (d3-q3) space is eliminated, the algorithm is enabled not to require excessive calculation quantity, a digital processor is liable to implement, the difficulty of program design is reduced, and the running power consumption of a digital chip is reduced.

Description

technical field [0001] The invention relates to the field of design and manufacture of a multi-phase motor AC control system (including a five-phase inverter and a five-phase permanent magnet synchronous motor) in the field of power electronics and electric transmission, especially a finite set model prediction of a five-phase permanent magnet synchronous motor current control method. Background technique [0002] The rapid development of microelectronics technology and power electronics technology has laid the foundation for the motor control system to get rid of the traditional three-phase topology limitation. The advantages of replacing the traditional three-phase with a multi-phase AC speed control system mainly lie in: 1) the frequency of the electromagnetic torque ripple is increased, the amplitude of the ripple is reduced, and the vibration and noise of the motor are reduced; 2) the current stress of the single switching device Small size, large inverter capacity, go...

AI Technical Summary

Problems solved by technology

The MPCC-11 algorithm only needs to repeatedly calculate 11 voltage vectors, but the magnitude of the voltage vector is single and the largest, which will cause large steady-state torque fluctuations of the motor, while the MPCC-21 and MPCC-31 algorithms can improve the steady-state of the motor performance, but it is necessary to perform repeated calculations on 21 and 31 voltage vectors respectively, the amount of calculation is huge, and the burden on the digital chip is heavy

In addition, when these three FCS-MPCC algorithms are digitally implemented, only a single voltage vector acts in each control cycle, so a higher sampling frequency is required to ensure better steady-state performance of the motor. The frequency requires that the time used for calculation should not be too long, which limits the implementation of MPCC-21 and MPCC-31 algorithms

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