What does high sampling and low compensation mean in reactive power compensation controllers

In practical applications, reactive power compensation controllers serve various functions and employ multiple compensation methods. Among these, "high sampling and low compensation" is the most commonly used. However, some users who are new to this device may not understand what "high sampling and low compensation" means. Therefore, we will now explain the concept of "high sampling and low compensation" in reactive power compensation controllers.

"High sampling and low compensation" in reactive power compensation controllers refers to an operational approach involving high-voltage sampling and low-voltage compensation. The specific details are as follows:

1. High-Voltage Sampling
Meaning: The controller collects voltage and current signals from the high-voltage side (e.g., 10kV or 6kV).
Purpose: Sampling on the high-voltage side provides a more accurate reflection of the system's overall reactive power demand, avoiding potential errors that may arise from uneven load distribution when sampling on the low-voltage side.

2. Low-Voltage Compensation
Meaning: Based on the data sampled from the high-voltage side, the controller performs reactive power compensation on the low-voltage side (e.g., 0.4kV).
Purpose: Low-voltage compensation devices (such as shunt capacitors) are cost-effective, easy to install, and maintain, making them suitable for compensation on the low-voltage side.

3. Workflow
Sampling: The controller collects voltage and current signals from the high-voltage side to calculate the system's reactive power and power factor.
Analysis: Based on the calculation results, it determines whether compensation is needed and the required compensation amount.
Control: If compensation is required, the controller switches the capacitor banks on the low-voltage side to adjust reactive power and improve the power factor.

4. Advantages
Accuracy: High-voltage sampling more accurately reflects the system's overall reactive power demand.
Cost-Effectiveness: Low-voltage compensation devices are economical and easy to install and maintain.
Flexibility: Low-voltage compensation allows for flexible adjustments according to changes in load.

5. Application Scenarios
Industrial Plants: Factories with high-voltage power supply and low-voltage loads.
Commercial Buildings: Large shopping malls, office buildings, and other venues with high-voltage power supply and low-voltage loads.
Power Systems: Settings such as substations that require high-voltage sampling and low-voltage compensation.