No-position sensor motor control device

Abstract

A position sensorless motor control apparatus is provided that achieves high resolution and high accuracy angle estimation, achieves angle estimation even in the presence of phase voltage saturation, and achieves high accuracy angle estimation even when a back electromotive force constant changes. An angle estimating unit which generates estimated rotor angle comprises: an estimation phase selecting unit for selecting an estimation phase designating the stator winding phase to be used for the generation of the estimated angle; a deviation generating unit for generating, based on the estimated angle and phase voltage value, a deviation relative to a model expressed by a phase voltage equation of the estimation phase; an angle correcting unit for correcting the estimated angle so that the deviation converges to zero; and an estimated coefficient value correcting unit for correcting an estimated coefficient value which is the estimated value of a coefficient in the phase voltage equation.

Description

technical field [0001] The invention relates to a position sensorless motor control device which rotates and drives the motor by estimating the rotor angle without using a position sensor. Specifically, it relates to a position sensorless motor control device that realizes high-precision angle estimation with high resolution, realizes angle estimation even when the phase voltage is saturated, and realizes high-precision angle estimation even when the induced voltage constant changes. Background technique [0002] Brushless motors without a mechanical commutation mechanism require electrical commutation according to the rotor angle. [0003] Existing motor control devices use position sensors such as Hall elements, resolvers, or optical encoders assembled on brushless motors to obtain rotor angle information. Therefore, the part of the position sensor increases the cost and also increases the size of the brushless motor. [0004] As a conventional position sensorless motor ...

AI Technical Summary

Problems solved by technology

However, when driven by a waveform other than a sine wave (such as a trapezoidal wave or a square wave, etc.), there is a problem that, for example, the trapezoidal wave or square wave added to the stator winding of a motor is transformed into waveforms on the γ-axis and δ-axis, which is extremely difficult. difficulty

Therefore, there is a problem that if the method of prior art example 2 is used for waveforms other than sine waves, an error in the estimated angle will occur.

Therefore, there is a problem that the velocity-induced electromotive force constant Kv varies with temperature as described above, so the angle estimation error increases with changes in ambient temperature or with an increase in the internal temperature of the device, etc.

[0088] However, the disadvantage is that the induced voltage e is a value that changes with temperature, so adding the estimated induced voltage em that does not consider the temperature change increases the residual error of the estimated angle when the temperature changes

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