Regenerative Braking and Brake (Shunt) Resistor

再生制动与泄放电阻（泄放模块）Advanced

A motor slowing down feeds energy back like a generator; a shunt resistor burns off the excess as heat.

When a motor decelerates or is driven backward by an external force — for instance, when a robot lands, crouches, or comes to an emergency stop — it briefly acts as a generator, feeding energy back onto the driver's DC bus; this is called regenerative braking. The bus voltage rises as a result, and if the battery or power supply can't absorb it, a shunt (or “dump”) circuit — a switching transistor plus a power resistor, also called a brake chopper — burns off the excess energy as heat once voltage crosses a threshold; otherwise the driver would trip an overvoltage fault or even be damaged. A battery-powered robot can recover some of that energy, but when the battery is already full, or the robot is powered from a lab DC supply that can't absorb reverse current, a shunt module becomes essential. It's directly tied to motor driver and power-supply design, as well as emergency-stop strategy.

ExampleA legged robot connected to a lab DC power supply for jump testing has its joint motors feed energy backward on landing, spiking the bus voltage and tripping an overvoltage fault on the driver; adding a shunt module across the bus resolves the problem.

Also called: Regenerative Braking, Brake Resistor, Shunt Resistor, Dump Module
Related: Servo Drive / Motor Driver · Brushless DC Motor · Battery Management System · Emergency Stop · Holding Brake
Sources: Regenerative braking - Wikipedia
Braking chopper - Wikipedia