Glossary · Automation fundamentals, platforms and components
Regenerative operation
Also known as: Generator mode, Regenerative braking
German: Generatorischer Betrieb
In electric drive technology, regenerative operation is the operating state in which an electric machine works as a generator, for example when braking or lowering a load, and converts mechanical energy back into electrical energy that flows into the drive's DC link or the supply.
- Automation components
In one sentence
In regenerative operation, a motor works as a generator while braking or lowering a load, feeding energy back to the drive or the grid.
Example
When the hoist lowers a load, the motor runs regeneratively and the drive dissipates the energy in a braking resistor.
How it applies
- Engineering: Regenerated energy raises the DC link Voltage of a frequency converter. It is either dissipated in a braking resistor, shared between drives on a common DC bus, or fed back to the grid by a regenerative (active front end) supply.
- Operation: If the drive cannot absorb the energy, it trips with an overvoltage fault, and the load may coast or be held by the brake.
- Documentation: Specify braking resistor ratings and the Thermal management needed, since resistors get hot. The maintenance manual should warn that DC link capacitors store energy after switch-off (Stored energy).
Regenerative operation vs. motor operation
In motor operation, electrical power is converted to mechanical power. In regenerative operation, torque and speed act in opposite directions, and power flows back from the load to the drive.