Application of SMES Unit to Improve DFIG Power Dispatch and Dynamic Performance During Intermittent Misfire and Fire-Through Faults

Abstract

The number of wind turbines connected to power grids has significantly increased during the last decade. This is mainly due to the convincing revolution in power electronic technology and the growing concern about greenhouse effect that is intensified due to the burning of fossil fuels. Variable-speed wind energy conversion systems (WECSs) such as doubly fed induction generators (DFIGs) are dominating the wind energy market due to their superior advantages over fixed-speed-based WECS which include more captured energy, less mechanical stress, and acoustical noise. DFIG is interfaced to the ac network through the grid-side voltage source converter (VSC) and rotor-side VSC to enable the variable-speed operation of the wind turbine and to provide reactive power support to the ac grid during disturbance events. Converter switching malfunction such as misfire and fire-through may influence the power dispatch capability of the DFIG. In this paper, a superconducting magnetic energy storage (SMES) unit is utilized to improve the power dispatch and dynamic performance of DFIG-based WECS during internal converter switching malfunctions such as misfire and fire-through faults. Simulation results without and with SMES connected to the system are presented, compared, and analyzed.Index Terms-Doubly fed induction generators (DFIGs), fire-through, misfire, superconducting magnetic energy storage (SMES).

Performance of LR-type solid-state fault current limiter in improving power quality and transient stability of power network with wind turbine generators

“…The penetration of wind energy in the power grid has brought up many questions about its compatibility with the power network. In particular, there are still debates about the impacts of WTGs on network stability, power quality, reliability, and system behavior during fault situations [1][2][3][4].…”

“…The penetration of wind energy in the power grid has brought up many questions about its compatibility with the power network. In particular, there are still debates about the impacts of WTGs on network stability, power quality, reliability, and system behavior during fault situations [1][2][3][4].With the rapid development of WTG and its increasing capacity, the level of the associated short-circuit current during a fault will also be increased in the power system [1,5,6]. As a consequence, the increased short-circuit current can have negative effects on the entire power network comprising of WTG with respect to the transient stability and the power quality.…”

DFIG-based WECS fault ride through complying with Australian grid codes

“…Among those, wind energy has been given a great attention and it is estimated to produce about 10% of the global electricity by the year 2020 [1]. DFIG based wind energy conversion system (WECS) is gaining popularity nowadays because of its superior advantages over other wind turbine generator concepts [2,3] and its application in large WECS has reached 55% of the worldwide total wind capacity during the year 2012 [4]. The typical configuration of DFIG is shown in Fig.…”

“…This configuration makes SMES highly efficient in storing electricity with typical efficiency in the range of 95%-98% [21]. Other advantages of the SMES unit include very quick response and possibilities for highpower applications [4]. The stored energy in the SMES coil can be calculated as [21] (1)…”

“…The values of and are generated through conventional PI controllers based on the error values of and . The value of and is converted through Park transformation (dq0 − abc) to produce the reference current ( ) [4].…”