(b)
Fig 7 Simulation results without compensation (a)Source current (b) %THD in phase-a of source current
Fig. 7 shows a system when DSTATCOM is not connected to it. It can be seen that the source current is highly non-sinusoidal and also the neutral current (In) is non-zero. Fig 6(b) shows the %THD in phase-a of source current it is about 17.86 % before compensation.
It is seen in fig 8(a) and (b) after the DSTATCOM is connected to the system the source current becomes sinusoidal and in phase with the source voltage. Fig 8(c) shows the DSTATCOM injected current into the distribution system. The %THD in phase-a of source current has now been reduced to 0.68% which is well within limit of 5% according to IEEE standard 519, this can be seen from fig. 8(d)