بهبود جبران‌سازی راه‌اندازی توربین انبساطی توسط DVR بهبودیافته و STATCOM در نیروگاه نکا تحت شرایط خطا

In order to prevent energy waste by throttle valve in gas pressure reducing station of Neka thermal power plant, a turbo-expander with a capacity of 9.8 MW for the power plant was prepared and installed. Due to the absorption of 63 MVAr reactive powers at the moment of turbo-expander starting, resulted in severe voltage drops in the power plant auxiliary service system. In this paper, while pathology of fault effect on turbo-expander operation will be considered its performance Improvement in the event of grid fault using modified DVR and STATCOM is also considered. To improve performance of DVR, a review of all topologies and control strategies of DVR compensator and improved topology is presented. Then, for optimal performance of compensators the possible points presence on the auxiliary service system of Neka power plant in various scenarios under conditions of sever disturbance, synchronization of fault occurring conditions and starting are tested. The results of PSCAD / EMTDC software simulation show by using improved topology and minimum injection active power strategy of DVR, severe voltage sag compensated in various scenarios and can provide the total auxiliary service system power consumption of this power plant by turbo-expander instead of using the generation of power plant.