Solution 3 Phase Current

Solutions:

Work order 1:

1.1  Delta connection

1.2  P = √3 U I      You use the line-values;  here cosφ = 1, because you have purely ohmic resistances

=> I = P / (√3 U) = 10000W / (√3 400V) = 14,43 A

1.3   P_total = 3 U_Phase * I_Phase = 3 U²_Phase / R_Phase     =>    R_Phase = 3 U²_Phase / P_Phase =  3 * 400²V² / 10000W = 48 Ω

Work order 2:

2.1   I_Phase = U / R    with  U = U_Phase, because you have Delta and

I_Str = U / R  = 400V / 80Ω = 5A

2.3   I = 8,66A

2.4   P_total = 6 kW

2.5   R_Total = 2R || R = 160Ω * 80Ω / (160Ω + 80Ω)

Aufgabe 3:

3.1   Delta

3.2   U = U_Phase = R * I_Phase = 80Ω * 5A = 400V

3.3   I = √3 * I_Phase = √3 * 5A = 8,66A

3.4   P = 3 P_Phase = 3 R * I²_Phase = 3 * 80Ω * 5²A *  = 6 kW

3.5    See work order 2