Enhanced fault ride through performance of self‐excited induction generator‐based wind park during unbalanced grid operation

Abstract

This study presents novel control design for improving the performance of large-scale wind park (LSWP) based on self-excited induction generator under unbalanced voltage conditions. A dual controller for static synchronous compensator (STATCOM) employing controller by employing positive-and negative-sequence synchronous frames is implemented and analysed in response to severely unbalanced voltage conditions. The test system simulated represents a wind park rated at 100 MW connected to a weak electrical grid. The potential of the dual STATCOM controller is evaluated and analysed for severely unbalanced voltage conditions at the grid interface of LSWP. The dual controller with STATCOM overloading capability is tested and compared with the performance of the positive-sequence controller in response to different types of asymmetrical grid faults at low short-circuit ratios. The simulations performed using PSCAD/EMTDC demonstrate superior performance of dual STATCOM control strategy for improving unbalanced operation, fault ride through capability and transient stability margin in response to severely unbalanced voltage conditions.

PV‐assisted microgeneration scheme with single‐phase induction generator suitable for wide speed range application

“…L αm and L βm are the magnetising inductances of α-β-axis, respectively. The stator flux ψ s can be derived from (5) and 6as…”

“…Among the renewable energy sources, wind energy is a well-established clean energy source although highly intermittent. Harvesting wind energy for electricity production using induction generators (IGs) [1][2][3][4][5] is commonplace. Although the large-scale grid-connected type is mostly in use [2][3][4][5], capacitor excited three-phase induction machines working as generators for grid-isolated operation is also common [6,7].…”

“…Harvesting wind energy for electricity production using induction generators (IGs) [1][2][3][4][5] is commonplace. Although the large-scale grid-connected type is mostly in use [2][3][4][5], capacitor excited three-phase induction machines working as generators for grid-isolated operation is also common [6,7]. Schemes involving three-phase IGs supplying single-phase loads have also been studied both for grid-connected as well as isolated applications [8][9][10][11][12].…”

Maximizing Instantaneous Active Power Capability for PWM Rectifier Under Unbalanced Grid Voltage Dips Considering the Limitation of Phase Current

“…Many control strategies for PWM rectifiers or other grid-connected converters under unbalanced grid voltages have been proposed [7]- [14]. The typical strategies are as follows: (1) The double dq synchronized rotation frame (SRF) was introManuscript received January 18, 2016; revised April 3, 2016; accepted April 24, 2016.…”

“…duced into the control of the converter, and the positive and negative sequence currents were controlled independently [7], [8]; (2) The method of a proportional resonant regulator tracking the current was used to control the converter under unbalanced grid voltages [9]- [11]; (3) Direct power control strategy is also applied to mitigate the influence of unbalanced grid voltages on the control system [12]- [14].…”