Sequence Circuit for a Δ -Connected Load

Consider the balanced Δ -connected load shown in Fig. 7.4 in which the load in each phase is denoted by Z_Δ . The line-to-line voltages are given by

Adding these three voltages we get

Fig. 7.4 Schematic diagram of a balanced Δ -connected load.

Denoting the zero sequence component V_ab , V_bc and V_ca as V_ab0 and that of I_ab , I_bc and I_ca as I_ab0 we can rewrite (7.30) as

Again since

We find from (7.31) V_ab0 = I_ab0 = 0. Hence a Δ -connected load with no mutual coupling has not any zero sequence circulating current. Note that the positive and negative sequence impedance for this load will be equal to Z_Δ .

Example 7.4