This paper presents Three novel error driven dynamic controllers for the Static Synchronous Compensator (STATCOM) Facts device to stabilize both Wind Energy Conversion stand alone systems (SWECS) as well as hybrid scheme of wind plus small hydro with employing self excited induction generator. The unified AC system of standalone wind energy conversion scheme and hybrid wind/small hydro scheme are connected to a hybrid electric load. Three novel error driven dynamic controllers are validated for the STATCOM as a voltage stabilization scheme. Two novel controller are error driven dynamic controllers with auxiliary tracking control loop. The first controller is tri loop dynamic error driven controller using the RMS Load bus voltage, RMS-Load Current and the instantaneous AC load power. The second controller is DC voltage dynamic tracking controller using the dc link capacitor voltage. The third dynamic controller is based on the decoupled (d-q) current control strategy, namely the direct and quadrature current component for the STATCOM current. The dynamic response results demonstrated the effectiveness of the STATCOM-Facts device in stabilizing both AC wind energy system and the hybrid wind/hydro scheme by ensuring effective generator/load bus voltage regulation and dynamic reactive power compensation under load, wind and other prime mover excursions.
In a deregulated electric service environment, an effective electric transmission and distribution networks are vital to the competitive environment of reliable electric service. Power quality (PQ) is an item of steadily increasing concern in power transmission and distribution. The traditional approach to overcoming capacity and quality limitations in power transmission and distribution in many cases is the addition of new transmission and/or generating capacity. This, however, may not be practicable or desirable in the real case, for many of reasons. From technical, economical and environmental points of view, there are two important - and most of the time combined - alternatives for building new transmission or distribution networks to enhance the transmission system capacity, and power quality: the Flexible alternating current transmission devices and controllers, and the distributed generation resources near the load centers. The connection of distributed generation to the distribution grid may influence the stability of the power system, i.e. angle, frequency and voltage stability. It might also have an impact on the protection selectivity, and the frequency and voltage control in the system. This paper presents a low cost FACTS based Dynamic Distribution System Compensator (DDSC) scheme for voltage stabilization and power transfer and quality enhancement of the distribution feeders connected to a dispersed wind generator, using MATLAB/ SimPower System simulation tool.
During the last two decades, renewable wind energy has become increasingly popular as a consequence of strong ecological concerns and appealing advantages with regard to economical energy solutions in remote communities. Furthermore, with very large wind farms emerging, the dispersed renewable wind energy is required to be fully connected to the electrical distribution networks. However, the integration of dispersed renewable wind energy will pose a great challenge to the power quality in the distribution networks when the weak nature of the grid in remote areas and the uncertainty of wind are taken into consideration.This paper presents a novel Modulated Power Filter Compensator (MPFC) for the distribution networks with dispersed renewable wind energy interfaced. A tri-loop error driven controller is used to adjust the PWM switching of the modulated power filter compensator. Full power factor correction and power quality improvement is validated under different operation conditions, like load switching and wind velocity excursions. The MPFC device is a member of novel FACTS based compensators developed by the first author.