For low-speed, high-torque applications (below 200 RPM), a motor with high inductance and high resistance is generally more suitable. When high speed and high performance are required, a motor with low inductance and low resistance is the better choice.
High-Inductance, High-Resistance Motors
Advantages: The required torque can be achieved with a relatively low current, allowing the use of a lower-current driver. This results in improved thermal performance, greater stability, and reduced noise for both the driver and the motor.
Disadvantages: Torque drops off rapidly at higher speeds, making these motors unsuitable for high-speed operation.
Low-Inductance, Low-Resistance Motors
Advantages: The driver can deliver higher voltage and current at high speed. These motors offer higher no-load start and run frequencies, exhibit a stiffer torque-speed characteristic, and maintain torque more effectively as speed increases.
Disadvantages: Current draw is significantly higher, operating voltage is relatively high, heat generation is substantial, and noise is more difficult to control. These motors also place higher performance demands on the driver.
Note: Higher phase resistance and inductance do not automatically mean greater holding torque. Rather, under the same voltage and current conditions, higher inductance and resistance allow the motor to deliver greater torque at low speeds.