c Van Von Vcn =0 120° Vanl Vonl Vcnl 120° -120° Van =Vploo Vm=Vp/-120° (a) Vm=V./-240°=V/+120° 120° Vam=Vn/0° 120° Vm=V/-120 an -120° Vm=V,/-240°=Vp/+120° Vam+Vm+Vcm=V,/0°+V/-120°+V,/+120 (b) =V1.0-0.5-j0.866-0.5+j0.866) Figure 12.7 Phase sequences:(a)abc or positive =0 sequence,(b)acb or negative sequence