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The response of the DSTATCOM-BESS system with an IM load is as depicted in Figure 4.9. It is well known that if Tm is positive, the machine operates as a motor, and if it is negative, the machine operates as a generator. Hence, the sign of the mechanical torque directs the mode of operation. It has been visualized that the motor takes a large starting current at the time of starting. Accordingly, DSTATCOM injects the compensating current to maintain the voltage at PCC and current sinusoidal. During this condition, the terminal voltage is also kept at its reference voltage and the battery starts charging. Also, the grid side and load side harmonics are depicted in Figures 4.10 and 4.11, respectively. The obtained harmonics are well below the international standard IEEE519-2014. Moreover, Table 4.1 illustrates the harmonics-based comparative analysis of all considered loads. The perceived results establish the performance of the DSTATCOM-BESS system.

Figure 4.9 Response of DSTATCOM-BESS under an induction motor load.

Figure 4.10 Source side frequency spectrum.

Figure 4.11 Load side frequency spectrum.

Table 4.1 Harmonics analysis under balanced loads.

S. No.	Type of load	Indirect current control theory controlled DSTATCOM-BESS
Source side THD	Load side THD
1	Linear load	0.57%	0.57%
2	Nonlinear load	0.44%	30.31%
3	Motor load	0.18%	2.50%