A device that converts alternating current to direct current is called a:

A device that converts alternating current (AC) to direct current (DC) is known as a rectifier. This process is essential in many electrical and electronic applications where a steady DC is required for devices like batteries, power supplies, and electronic circuits.

The rectification process typically involves the use of diodes, which allow current to flow in one direction only. In this way, the rectifier takes the alternating waveform of AC, which fluctuates in both positive and negative cycles, and converts it into a unidirectional flow of current, effectively smoothing out the oscillations to produce a stable DC output.

Understanding this conversion is fundamental in control systems where DC actuators and sensors are employed, ensuring that the control systems function properly and reliably.