Type 1-4 Wind Turbine Generators: Fault Analysis for Grid Integration

Wind turbines provide a practical source of renewable energy which has developed from the historical wind-mill design to the extensive wind-farms located throughout the world today. Wind-farms incorporate a number of individual wind turbine generators which produce electrical energy which is then collected and transferred to the electricity grid. Wind turbines achieve this energy conversion through a range of technologies which has developed over the years from the robust coupled induction machine to the modern de-coupled asynchronous machine. This paper researches the technology applied within Type 1-4 wind turbine generators and develops simplified equivalent circuits within Matlab which can be used to analyse the expected fault current waveforms produced by each generator. Generic wind farm components are included which are used to determine Thevenin equivalent source impedance which is used within Power Industry software (PSSE Sincal) to investigate the effect of the generation in-feed on the grid protection scheme. Generic modelling of Type 1-4 turbine generators is carried out on the 132 kV Yass-Goulburn Transmission network which is owned and operated by Essential Energy, whilst a Type 3 wind turbine case study is derived from the 46.5 MW Gunning Wind Farm, which interconnects with the case study Transmission network mentioned above