Applying a STATCOM for stability improvement to an existing wind farm with fixed-speed induction generators

Abstract

Wind farms are becoming important distributed renewable energy resources. However, voltage stability issues with wind farms employing fixed-speed induction generators may require such systems to be augmented with dynamic compensation devices, such as STATCOM units. In preparation for deployment of a 10 MVA STATCOM at an existing wind farm in the Bonneville Power Administration (BPA) system, the STATCOM controller is to be tested through hardware-in-theloop simulation with a real-time digital simulator, which will model both the BPA system and wind farm with high fidelity, transient models. This paper presents groundwork conducted in preparation for the dynamic testing of the controller, including studies of the stability improvement facilitated by the introduction of the STATCOM into the BPA system. The enhancement of voltage stability and induction generator stability by the STATCOM is studied analytically by powervoltage and torque-slip relationships of a simple wind power system, as well as through simulation studies with the real-time simulation to be used for testing of the controller. Simulation results from both approaches are compared and illustrate the potential benefit of the STATCOM in preventing voltage collapse caused by serious network changes, such as opening a line, as well as improvement of the Fault Ride Through capability of the wind power system. Index Terms-fault ride through, high fidelity simulations, RTDS, stability, STATCOM, wind farm.

Evaluating the performance of external fault ride-through solutions used in wind farms with fixed speed induction generators when facing unbalanced faults

“…However, concerning FRT capability improvement of wind farms equipped with FSIG, it is essential to inject the appropriate amount of reactive power within the minimum time delay, since this fact influences notably the recovery process, as already mentioned previously. Therefore, the vector control technique is commonly used to deal with fast dynamics and to provide decoupled control ability (Gaztañaga, 2007), (Qi, 2008), (Chen, 2007), (Molinas, 2007), (Rao, 2000).…”

“…Therefore additional external power electronic compensation devices are necessary to fulfil the FRT requirements (Qi, 2008), (Marques, 2006). Although these two devices can improve the stability performance of FSIG directly connected to the grid, simulation results show that the utilization of a STATCOM with the same power capability of a SVC may lead to a better dynamic performance of the FSIG.…”

Interaction analysis between induction motor loads and STATCOM in weak grid using induction machine model

“…Owing to the reactive power consumption characteristics of IM loads in power systems, reactive compensation devices is necessary. For effective control and good compensation performance [2,3], static synchronous compensators (STATCOM) are widely employed for reactive power compensation. Research on induction machines and STATCOMs is mostly concerned about low voltage ride through characteristics [4,5], improvement of voltage sag due to starting of high power induction motor [6] and stabilizing of sub-synchronous resonance [7].…”

Voltage Regulation of Grid Connected Wind Farm Using STATCOM

“…The STATCOM with reduced capacitor bank can decrease the voltage fluctuations of multi-machine power system as well as wind generator terminals [4]. STATCOM technology to have the capability to increase stability and improve system dynamic response following disturbances [5]. The application of STATCOMs is to increase power quality and to reduce transmission line losses which have been also studied for wind power systems.…”