[問題] 電力電子

看板Electronics作者twns (twns)時間14年前 (2009/11/24 16:53)推噓-4(1推 5噓 12→)

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1. Estimate dominant harmonic components (to three times of the switching frequency) of both phase and line voltages for a three-phase voltage source inverter by using Bessel approximation. Assume the DC bus voltage is 400V, the fundamental and switching freguency are 50Hz and 1050Hz, respectively. 2. Voltage and cueeent in a three-phase four-wire system are given as follows: Va(t)=100 cos(wt+20) Ia(t)=10 cos(wt) Vb(t)= 80 cos(wt+100) Ib(t)=12 cos(wt+60) Vc(t)=120 cos(wt-100) Ic(t)= 8 cos(wt-60) A. Use symmetrical component transformation to derive positive,negative, and zero sequence components for both voltage and current, and calculate complex power. B. Derive voltage space vector, current space vector, and calculate complex power by using space phasor method. 3. For the following three-phase voltage Va(t)=100 cos(wt) Vb(t)=100 cos(wt-180) Vc(t)=0 A. Derive Vs,qd? <===========定子的Vqd B. Derive Ve,qd (轉子的Vqd) in the positive-sequence rotational frame (w)? C. Derive Ve,qd (轉子的Vqd) in the negative-sequence rotational frame (-w)? -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.117.165.201

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phylin

11/24 17:19, , 1^F

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lien

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joy830

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