Combined active and reactive power control with converter interfaced energy sources

Reactive power control using converter interfaced energy sources is possible and considered advantageous in certain grids. However, in some cases this is not enough to ensure good voltage quality at the connection point (PCC). It has been shown in this paper that the control of active power, along with the reactive power, can help in relieving the constraints over the injected reactive power and at the same time adds more control flexibility. The control of active power has been realized by using a simple current chopper at the DC-link. It has been shown that with combined active and reactive power control, the voltage quality at both the PCC and DC-link has been enhanced. Moreover, the number of the estimated trips of the converter-interfaced energy source is reduced.