Which device is used to switch electrical power with high efficiency for motor control?

Which device is used to switch electrical power with high efficiency for motor control?

• A. IGBT
• B. Diode
• C. Transformer
• D. Resistor

Answer: (A)

Efficient motor control relies on a device that can switch high power levels on and off rapidly with low losses. The insulated-gate bipolar transistor (IGBT) fits this role because it combines easy gate control with the ability to handle large currents and high voltages, and it can switch at the high frequencies used in PWM inverter drives. This enables precise speed control with minimal heat generation. Diodes conduct but can’t be actively switched in sync with the drive to modulate power, so they’re mainly used for freewheeling paths rather than as the main switch. A transformer changes voltage levels but doesn’t perform switching by itself, and a resistor wastes power without providing efficient switching.

Efficient motor control relies on a device that can switch high power levels on and off rapidly with low losses. The insulated-gate bipolar transistor (IGBT) fits this role because it combines easy gate control with the ability to handle large currents and high voltages, and it can switch at the high frequencies used in PWM inverter drives. This enables precise speed control with minimal heat generation. Diodes conduct but can’t be actively switched in sync with the drive to modulate power, so they’re mainly used for freewheeling paths rather than as the main switch. A transformer changes voltage levels but doesn’t perform switching by itself, and a resistor wastes power without providing efficient switching.