1.we can connect the capacitor in parallel to improve the power factor 2.we can connect the reactor in parallel to avoid the increasing of voltage If we can connect the capacitor in parallel to improve the power factor, can we connect the "inductor" in parallel to improve the power factor? If not, why?
These two basic combinations, series and parallel, can also be used as part of more complex connections. Figure 8.3.1 8.3. 1 illustrates a series combination of three capacitors, arranged in a row within the circuit. As for any capacitor, the capacitance of the combination is related to both charge and voltage:
The parallel capacitor provides reactive power compensation to ensure the stability of the system’s voltage. When the parallel capacitor is placed into the system, it will produce large switching inrush current, which must be less than twenty times the rated current.
Figure 8.3.2 8.3. 2: (a) Three capacitors are connected in parallel. Each capacitor is connected directly to the battery. (b) The charge on the equivalent capacitor is the sum of the charges on the individual capacitors.
When there are harmonic sources in a system, a parallel capacitor will enlarge the harmonics, producing harmonic resonance. Since it is an effective strategy to install a suitable reactance rate of reactor into the capacitor to restrain the harmonics, further analysis is necessary on the choice of reactance rate.
This equation, when simplified, is the expression for the equivalent capacitance of the parallel network of three capacitors: Cp = C1 +C2 +C3. (8.3.8) (8.3.8) C p = C 1 + C 2 + C 3. This expression is easily generalized to any number of capacitors connected in parallel in the network.