In this topic, you study Controlled rectifier (AC to DC converter) – Definition & Theory.
A controlled rectifier is an electrical circuit, converts a fixed voltage AC to a variable voltage DC. It is used primarily to control the speed of DC motors, such as those used in rolling mills. Figure 1 shows the block diagram of a closed-loop speed control scheme for DC motors using a thyristor phase controlled rectifier.
Fig. 1: Block diagram of thyristorised speed control DC motor