Question

Consider the D-STATCOM shown in Figure 3. Assume that a six-pulse VSC operating on sinusoidal PWM is employed for the D-STATCOM. Calculate the modulation index required: (1) to generate 5 Mvar of reactive power; and (2) to absorb 5 Mvar of reactive power. Data: For a six-pulse VSC oper =0.612 x ma x VDc where VLL is the line to line voltage at D-STATCOM terminals, ma is the modulation index and VDc is the DC capacitor voltage. Assume the base MVA is 10 MVA, the base primary voltage of the transformer is 13.8 kV and the base secondary voltage is 3 kV. [15 points] on sinusoidal PWM VLL 13.8 kV 13.8/3 kV 10 MVA 25% ISTATCOM VSTATCOM PWM -VSC 5 kV

Answer 1

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MVAR reactive Pouer a bsorb (2 TO -0 S P. u Qst (Vst (Vst0)) Vs t O 8536 more CloK to The Vst -As Voltog P.u, Vst O8536 Ta t Co acceptabe Solutfan Co 8536x3) 2 5608k V Vst O612X MaVpr Vし2 2 2:S608 o.&36 9