Generators don't directly control the load they supply. Instead, they maintain a stable voltage and frequency to ensure the connected equipment operates correctly.
Here's how it works:
1. Voltage Regulation
- Automatic Voltage Regulators (AVRs) are built into generators to maintain a consistent output voltage.
- They sense changes in voltage and adjust the generator's field excitation (magnetic field strength) to compensate.
- This keeps the voltage output within a specified range, even as the load changes.
2. Frequency Regulation
- Governor systems control the generator's speed, which directly affects the output frequency.
- When the load increases, the generator's speed slows down. The governor senses this and increases the fuel supply to the engine, restoring the speed and frequency.
- Conversely, when the load decreases, the speed increases, and the governor reduces the fuel supply to maintain the desired frequency.
3. Load Sharing
- In systems with multiple generators, load sharing ensures that each generator contributes its fair share of the total load.
- This is achieved through load-sharing controllers that monitor the power output of each generator and adjust their output accordingly.
4. Protection Systems
- Generators are equipped with protection systems to prevent damage from overloads, faults, or other abnormal conditions.
- These systems can disconnect the generator from the load or initiate other protective measures to ensure safe operation.
In summary, generators don't directly control the load. They provide a stable voltage and frequency, allowing the connected equipment to operate reliably. AVR and governor systems ensure the generator's output remains within acceptable limits, while load sharing and protection systems enhance the overall system's stability and safety.
