Weekly topic: The motor of the high-pressure slurry pump generates heat when the frequency of the slurry pump changes – is this heat generation due to low load or high load?

Fever at low load. The inverter (DC/AC conversion) section of the frequency converter uses IGBTs to generate a sine wave-shaped current waveform through sine pulse width modulation SPWM. The value of the carrier frequency directly affects the quality of the current waveform as well as the level of interference; it is a very sensitive and critical parameter. Therefore, during operation, it is necessary to first select the appropriate carrier frequency value, and only after that consider adding various devices for harmonic suppression, such as AC reactors, DC reactors, filters, and interleaved reactors, along with measures related to wiring and grounding. This approach is more reasonable and effective; it is important to follow this principle and not to handle the issue in the wrong manner. When the carrier frequency is high, the current waveform has good sinusoidality and is smooth. In this way, the harmonics are reduced and interference is minimized; otherwise, the performance is poor. When the carrier frequency is too low, the effective torque of the motor decreases, losses increase, and the temperature rises. On the other hand, when the carrier frequency is too high, the losses of the inverter increase, the temperature of the IGBTs rises, and at the same time the rate of change of the output voltage, dv/dt, increases, which has a significant impact on the insulation of the motor.