Power Supplies for AC Motor Evaluation
Evaluating 3-Phase AC Motor Characteristics
Here are some examples of the 3-phase AC motors applications.
In the example presented here, instead of an inverter, a high-capacity smart AC/DC regulated power supply PCR-WEA/WEA2 series is used to run the motor.
Motors used in EVs and PHVs are mainly three-phase synchronous motors. To properly run the motors, a controller is required. In this case, the PCR-WEA/WEA2 series is a simulation inverter that operates precisely according to the controller’s commands.
PCR-WEA/WEA2 series can be used to evaluate three-phase motor characteristics. Since it generates clean three-phase AC waveforms, the PCR-WEA/WEA2 series can replace a PWM inverter by inputting voltage analog signals from the motor’s driver.
For acquiring basic characteristics of a motor, it is recommended to isolate it and remove any PWM inverter characteristics.
The Key Feature Is
Low-Distortion AC Waveform
Here are the advantages of using the PCR-WEA/WEA2 series:
The first advantage is a wide frequency bandwidth of up to 5kHz, which is enough to drive a 20,000 rpm high-speed motor.
The second one is low distortion and low noise. The device can supply clean waveforms that make it possible to verify the true motor characteristics.
The third advantage is the built-in arbitrary waveform function, which can also be used to reproduce inverter waveforms in vehicles. The PCR-WEA/WEA2 series has a high carrier frequency and can even be used to recreate noisy waveforms.
Evaluating 3-Phase Generators and Their Characteristics
Here we present an example of how the back EMF and regenerative power a generator motor produces is handled.
The PCR-WEA/WEA2 series is equipped with a power regeneration function as standard. The regenerative power can be up to 100% of the power supply capacity and this can be supplied continuously.
Therefore, the regenerative power generated during braking can be safely received.
Thanks to the standard output impedance setting function, this power supply can be used as a pseudo-resistive load. When used as a pseudo-resistive load, the set voltage should be lower than the generator’s voltage.
A current proportional to the set impedance value is supplied, and power can be regenerated.
Regeneration Demonstration
Here we present a useful tip.
The power supply’s output impedance function can be used for regenerative operation. The key is to set the power supply voltage lower than the motor output voltage.
When this function is on, the system can work as a power regeneration simulation load during continuous operation. This reduces energy consumption and contributes to CO2 emission reduction. Also, since the system supports AC and DC voltage, it can be used for various applications.
