The on-site reactive power compensation capacity can be determined based on the following empirical formula:
In equation Q ≤ U Ι 0:
Q - Reactive power compensation capacity (kvar);
U - Rated voltage of the electric motor (V);
Ι 0 - Motor no-load current (A);
However, on-site reactive power compensation also has its drawbacks:
⑴ Cannot fully replace high-voltage centralized compensation and low-voltage grouped compensation;
As is well known, reactive power compensation can be divided into high-voltage centralized compensation, low-voltage group compensation, and low-voltage on-site compensation according to their installation location and wiring method. The on-site compensation area is the largest and the effect is also good. But its total capacitor installation capacity is larger than the other two methods, and the capacitor utilization rate is also low. The capacitors for high-voltage centralized compensation and low-voltage grouped compensation have relatively small capacities, high utilization rates, and can compensate for the reactive power losses of transformers themselves.
Therefore, each of these three compensation methods has its own scope of application, and their usage scenarios should be determined based on actual situations, with each method performing its own duties and classification.