Permanent-magnet synchronous motor control system and method

Abstract

The invention discloses a permanent-magnet synchronous motor control system and method. The system comprises a lifting speed controller, a V / F curve controller, an SPWM modulator, a voltage source inverter, a permanent-magnet synchronous motor, a coordinate transformation circuit, a voltage compensation circuit and a rotational-speed compensation circuit. The V / F curve controller obtains a compensated rotational speed according to a given rotational speed and a compensating rotational speed; the V / F curve controller obtains given voltage according to the compensated rotational speed and a V / F control curve; the SPWM modulator obtains compensated voltage according to the given voltage and compensating voltage; the SPWM modulator conducts sinusoidal pulse width modulation on the compensated voltage to obtain a modulation signal; the voltage source inverter conducts inversion according to the modulation signal to obtain three-phase current and outputs the three-phase current to the permanent-magnet synchronous motor. According to the permanent-magnet synchronous motor control system and method, through the rotational speed compensation and stator voltage compensation of the permanent-magnet synchronous motor, the changes of reactive power are inhibited, the reactive power of the system is kept unchanged, and therefore the fluctuation of reactive current and the oscillation of the system are inhibited, and the system runs smoothly.

Description

technical field [0001] The invention relates to the technical field of automation control, in particular to a permanent magnet synchronous motor control system and method. Background technique [0002] With the development of power electronics technology, microelectronics technology, sensor technology, rare-earth permanent magnet materials and motor control theory, the research and application of permanent magnet synchronous motors have received widespread attention. Permanent magnet synchronous motors do not require current excitation, brushes and slip rings, and have the advantages of simple structure, high efficiency, high power factor, high power density, small size, low moment of inertia, easy heat dissipation and maintenance. With the improvement of the magnetic properties of materials and the emergence of new permanent magnet materials, in motion control systems with high precision, high reliability and wide speed range, high-power permanent magnet synchronous motors ...

AI Technical Summary

Problems solved by technology

When the permanent magnet synchronous motor is under open-loop control, the fluctuation of the reactive current of the permanent magnet synchronous motor will cause the air gap flux linkage to oscillate, which will lead to the unstable operation of the open-loop control system under no-load and light-load conditions

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