OLTC transformer model connecting 3-wire MV with 4-wire multigrounded LV networks

• A new OLTC transformer modeling technique is proposed. Taps are modelled as equivalent current sources. Power flow analysis significantly accelerated. Applicable to 3-wire medium voltage and 4-wire multigrounded low networks. This short communication presents a comprehensive model of on-load tap-changer (OLTC) transformers that connects (MV) with (LV) The proposed enables the inclusion MV network LV into single Y BUS matrix without any assumption or simplification. Its distinct feature tap changer simulated outside matrix, thus refactorization not required in every change. has been validated 4-Bus network, while its performance tested IEEE 8500-Node 906-Bus test