Scaled Down Model of WECC 3-Machine 9-Bus System with Frequency-Dependent Lines

A scaled-down model of WECC 3-machine 9-bus system is being developed as part of a Smart Energy Systems Infrastructure-Hybrid Test Bed (SESI-HTB) at the Electrical Engineering Department, Indian Institute of Science, Bangalore. Laboratory models developed in the past used lumped parameter models for transmission lines. The constant impedance transmission lines of 230 kV are replaced with the frequency-dependent (FD) models to accurately represent the transient phenomenon over a wide range of frequencies. Original WECC model only provides per unit data. To realize these FD lines standard tower and conductor configurations are used to match with the original test system data and power flow results. To realize the transmission lines physically, lumped parameter frequency-dependent (LPFD) models are derived for all the 230kV lines using a single step fitting algorithm. Procedure used to scale down the 230kV LPFD line models to 220V laboratory model is presented. The WECC model with LPFD lines and scaled-down LPFD (SD-LPFD) lines are validated by comparing their transient responses with the FD line model of EMTP-RV.