کنفرانس مهندسی برق ایران

صفحه اصلی / بیست و نهمین کنفرانس مهندسی برق ایران

Improved Low Voltage Ride Through by A STATCOM Based on Neutral Point Piloted (NPP) Multilevel Inverter

نویسندگان :

Yousef Neyshabouri¹ Mohammad Farhadi-kangarlu²

1- دانشگاه ارومیه 2- دانشگاه ارومیه

کلمات کلیدی :

(Multilevel inverter, STATCOM, low-voltage ride through, neutral point piloted inverter (NPPI

چکیده :

By increasing use of renewable energy resources, grid codes impose strict standards for reactive current compensation for low voltage ride through (LVRT). On the other hand, multilevel voltage source inverters have achieved prominent attention due to the their lower dv/dt and harmonic content. This paper introduces a STATCOM based on neutral point piloted inverter (NPPI) for the first time. The studied 5-level NPPI has a single dc bus which feds all phases of the inverter and each phase contains two internal flying capacitors. A control system has been developed for NPPI-STATCOM through which the voltage of dc bus capacitor is controlled at its reference and using redundant switching states, the voltages of flying capacitors are balanced as well. Owing to its circuit topology, the active power can be exchanged among the inverter phases. Thus, NPPI-STATCOM control system is capable of balancing the voltage of internal capacitors even being connected to a faulty grid while positive and negative-sequence reactive currents being injected to the grid. Several simulation results in MATLAB/SIMULINK confirm the above claims indicating the performance of NPPI-STATCOM and the developed control system.