| 摘要 |
A sensorless motor drive apparatus (see figure 2) includes a unit for determining whether or not there is an error in the estimate of the rotor position used in the motor control. This determination is achieved by detecting the three-phase current fed to the motor, converting these values into a stationary coordinate system using an estimated angle of the rotor, then converting into a synchronous coordinate system, then performing a calculation and comparing the result of the calculation with a known value representing an accurate estimation. If the result of the calculation is not equal to the known value, then there is an error in the estimated rotor position, and the PWM power is withdrawn from the motor preventing faulty operation and damage to the motor and compressor. |
