Drive system of synchronized electric motor

Abstract

Provided is a drive system of a synchronized electric motor that is capable of driving at speeds near zero. An electricity supply mode determination apparatus (9) detects either an electricity non-supply phase terminal potential of a three-phase synchronized electric motor (4) or a stator coil connection point potential (neutral point potential) of the three-phase synchronized transmitter, and sequentially switches among six electricity supply modes on the basis of the detected value of the potential. In order to supply repeating waveforms of three types of voltage to the synchronized electric motor, said three types of voltage being a positive polarity pulse voltage that causes the synchronized electric motor to generate a positive rotation torque, an inverse pulse voltage that causes the synchronized electric motor to generate an inverse rotation torque, and a zero voltage, as line voltage waveforms of electricity supply phase in each of the six electricity supply modes, a voltage instruction compensator apparatus (8) uses a degree of compensation deltaV to compensate for a voltage instruction that is applied to the synchronized electric motor. The electricity supply phase line voltage is applied to the synchronized electric motor.

Description

technical field [0001] The present invention relates to a drive system for a synchronous motor, and more particularly to a drive system for a synchronous motor suitable for use in estimating the magnetic pole position of a rotor in a sensorless manner and controlling the synchronous motor. Background technique [0002] In the fields of home appliances, industry, and automobiles, for example, motor drives are used for rotational speed control of fans, pumps, compressors, conveyors, elevators, etc., as well as torque assist equipment and positioning control. Among motor drives in these fields, small and highly efficient permanent magnet motors (synchronous motors) are widely used. However, when driving a permanent magnet motor (hereafter referred to as "PM motor"), information on the magnetic pole position of the motor rotor is required, and position sensors such as resolvers and Hall ICs are necessary for this purpose. In recent years, "sensorless control" in which the rotat...

AI Technical Summary

Problems solved by technology

At present, most of the sensorless control that has been put into practical use is based on the induced voltage (speed voltage) generated by the PM motor. Therefore, the sensitivity is low in the stop and low speed range of small induced voltage, and the position information will be submerged in the in the noise

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