Vector control of permanent magnet synchronous motors without position and speed sensors

et al. 2013

Energies

Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation. This paper presents a simulation model of a MW-level variable speed wind turbine with a full-scale back-to-back power converter and permanent magnet synchronous generator (PMSG) developed in the simulation tool of PSCAD/EMTDC. Flicker emission of this system is investigated. The 3p (three times per revolution) power oscillation due to wind shear and tower shadow effects is the significant part in the flicker emission of variable speed wind turbines with PMSG during continuous operation. A new method of flicker mitigation by controlling the rotational speed is proposed. It smoothes the 3p active power oscillations from wind shear and tower shadow effects of the wind turbine by varying the rotational speed of the PMSG. Simulation results show that damping the 3p active power oscillation by using the flicker mitigation speed controller is an effective means for flicker mitigation of variable speed wind turbines with full-scale back-to-back power converters and PMSG during continuous operation.

Section: Control Schemesmentioning

confidence: 99%

Flicker Mitigation by Speed Control of Permanent Magnet Synchronous Generator Variable-Speed Wind Turbines

Zhang

et al. 2013

Energies

“…Vector control techniques have been well developed for PMSG using back-to-back PWM converters [14]. In this paper, two vector control schemes are designed respectively for the generator-side and grid-side PWM converters.…”

Section: B Wind Turbine Control Schemesmentioning

confidence: 99%

Influence of wind plant ancillary voltage control on system small signal stability

2012 9th International Conference on the European Energy Market

2012

Abstract-As a common tendency, large-scale wind farms are increasingly connected to the transmission system of modern power grids. This introduces some new challenges to the connected power systems, and the transmission system operators (TSOs) have to put some new requirements as part of the grid codes on the integration of wind farms. One common requirement to wind farms is the function of system voltage control which can be implemented in the grid-side convertor controller of a variable speed wind turbine. This ancillary voltage control provided by wind farms could have some influence on the system small signal stability. This paper implements an ancillary voltage control strategy on a direct-drive-full-convertor-based wind farm and studies its influence on the damping ratio values of the dominant oscillation mode within the connected power system. All the calculations and simulations are conducted in DIgSILENT PowerFactory 14.0.Index Terms-ancillary voltage control, direct-drive-fullconvertor-based wind turbines, small signal stability

“…Vector control techniques have been well developed for PMSG using back-to-back PWM converters [17]. Two vector control schemes are designed respectively for the generatorside and grid-side PWM converters, as shown in Fig.…”

Section: Bmentioning

confidence: 99%

Impact of wind shear and tower shadow effects on power system with large scale wind power penetration

IECON 2011 - 37th Annual Conference of the IEEE Industrial Electronics Society

2011

Grid connected wind turbines are fluctuating power sources due to wind speed variations, the wind shear and the tower shadow effects. The fluctuating power may be able to excite the power system oscillation at a frequency close to the natural oscillation frequency of a power system. This paper presents a simulation model of a variable speed wind farm with permanent magnet synchronous generators (PMSGs) and fullscale back-to-back converters in the simulation tool of DIgSILENT/PowerFactory. In this paper, the impacts of wind shear and tower shadow effects on the small signal stability of power systems with large scale wind power penetrations are investigated during continuous operation based on the wind turbine model and the power system model.