Static Excitation Controller Research Articles

Efficiency of a Six-Phase Induction Generator Employing a Static Excitation Controller to Generate AC Power for Wind Energy

The most widely applied six phase induction generator (SPIG) leads to insufficient frequency regulation ability of power system. A six phase induction generator (SPIG) Combined with appropriate capacitors and a motor, it produces an induction generator that is self-excited. The advantage of this generator, which has recently caught the interest of various experts, particularly in the field of wind energy, combines the advantages of multiphase devices. This study aims to offer a technique for regulating the voltage of a wind-powered SPIG. The methodology suggests two different compensation setups for (V-f) control, involving two switching capacitors. Different setups’ performance constraints, controls, and features will be closely scrutinized and contrasted. The performance limits of the suggested system will be contrasted. to those of variable speed and variable capacity systems after being modelled and simulated. The results show that using the optimal capacitances for each configuration improves voltage and frequency regulation significantly. The preferable option, however, is short-shunt compensation since it regulates the output voltage and frequency with the fewest capacitances and the least amount of necessary duty fluctuation.

Performance of Boost Converter with Fuzzy Logic Controller to Increase the DWIG Speed Range in Wind Power System

In this paper the wind energy conversion with a variable speed of wind turbine connected to the grid which is based on dual stator induction generator (DWIG) which is excited by Static Excitation Controller (SEC) on the Control winding side which utilized by Control –Winding Voltage Oriented Control (CWVOC), and followed by Step up converter at the power winding side which utilized Fuzzy Logic Controller in its control strategy to increase the speed range of DWIG. The performance of boost converter with FLC in increasing the wide range of speeds can be executed by using mat lab/Simulink.

Control and Performance of Five-Phase Dual Stator-Winding Induction Generator DC Generating System

In this paper, the five-phase dual stator-winding induction generator dc generating system with the static excitation controller is presented, and two kinds of control strategies for this system are proposed. In this generator, the cage-type rotor is employed, and two sets of five-phase windings are placed in the stator, namely, the power winding and control winding. Using the instantaneous power theory, the control-winding-flux-oriented control (CWFOC) strategy without harmonic injection is obtained. To improve power density, the CWFOC with harmonic injection is proposed as well. For these two strategies, the detailed implementation is studied. The results (simulation and experiment) support the correctness and effectiveness of the proposed control strategies, and the corresponding results show that, using the CWFOC strategy with harmonic injection, the output power of this system can be improved by about 11%.

Grid-Connected Dual Stator-Winding Induction Generator Wind Power System for Wide Wind Speed Ranges

This paper presents a grid-connected dual stator-winding induction generator (DWIG) wind power system suitable for wide wind speed ranges. The parallel connection via a unidirectional diode between dc buses of both stator-winding sides is employed in this DWIG system, which can output a high dc voltage over wide wind speed ranges. Grid-connected inverters (GCIs) do not require booster converters; hence, the efficiency of wind energy utilization increases, and the hardware topology and control strategy of GCIs are simplified. In view of the particularities of the parallel topology and the adopted generator control strategy, we propose a novel excitation–capacitor optimization solution to reduce the volume and weight of the static excitation controller. When this excitation–capacitor optimization is carried out, the maximum power tracking problem is also considered. All the problems are resolved with the combined control of the DWIG and GCI. Experimental results on the platform of a 37 kW/600 V prototype show that the proposed DWIG wind power system can output a constant dc voltage over wide rotor speed ranges for grid-connected operations and that the proposed excitation optimization scheme is effective.

Control and Implementation of Dual-Stator-Winding Induction Generator for Variable Frequency AC-Generating System

This paper presents the control and implementation of the dual-stator-winding induction generator for variable frequency AC (VFAC) generating system. This generator has two sets of stator windings embedded into the stator slots. The power winding produces the VFAC power to feed the loads, and the control winding is connected to the static excitation controller to control the generator for output voltage regulation with speed and load variations. On the basis of the idea of power balance, an instantaneous slip frequency control (ISFC) strategy using the information of both the output voltage and the output power is used in this system. A series of experiments is carried out on a 15 kW prototype for verification. Results show that the system has good static and dynamic performance in a wide speed range, which demonstrates that the ISFC strategy is suitable for this system.

An Integrated AC and DC Hybrid Generation System Using Dual-Stator-Winding Induction Generator With Static Excitation Controller

This letter proposes an integrated ac and dc hybrid generation system based on the dual-stator-winding induction generator with the static excitation controller (SEC). In this generator, not only the power winding can output the variable-frequency ac power, but also the control winding can provide the high-voltage dc power through the dc bus of the SEC, which implements the electric integration by only one generator. An instantaneous slip frequency control strategy is employed to guarantee the system a good performance. The experimental results verify the correctness and effectiveness of the proposed scheme.

A Stand-Alone Dual Stator-Winding Induction Generator Variable Frequency AC Power System

This letter proposes a variable frequency ac (VFAC) stand-alone power system based on the dual stator-winding induction generator (DWIG) with the static excitation controller (SEC). A slip frequency control strategy using the information of the output voltage and the output power is employed to guarantee that the system has a desirable static and dynamic performance in a wide speed range. The experimental results on a prototype verify the principle and performance of the proposed control method.

An Excitation-Capacitor-Optimized Dual Stator-Winding Induction Generator With the Static Excitation Controller for Wind Power Application

This paper presents an optimal scheme of excitation capacitor to decrease the capacity of static excitation controller (SEC) for dual stator-winding induction generator (DWIG) system applied in wind power generation. The investigations into reactive excitation power released by the excitation capacitor and SEC illustrate that the optimal excitation capacitor is not only related to generator parameters, speed range, and load, but also affected by wind turbine power curve. Based on the objective of minimizing the capacity of SEC, several methods are employed here to select an appropriate excitation capacitor. Through the analysis of DWIG control mechanism and model of SEC in the stator-voltage-orientation synchronous d-q frame, a decoupling control strategy using the space vector modulation is obtained. On the basis of this, the simulation and experimental works from the prototype of 18-kW six/three-phase DWIG wind power system are carried out to verify the optimal scheme. The results demonstrate the correctness and effectiveness of this optimization scheme.

The Capacity Optimization for the Static Excitation Controller of the Dual-Stator-Winding Induction Generator Operating in a Wide Speed Range

The dual-stator-winding induction generator (DWIG) designed to achieve wide-speed-range operation with reduced capacity of the static power controller is presented. The DWIG consists of a standard squirrel-cage rotor and a stator with two separate windings wound for the same number of poles. This generator has a diode bridge rectifier load connected across to the power winding and a static excitation controller (SEC) to the control winding. Investigations into the reactive power released by the fixed excitation capacitor bank versus rotor speed under various loads represent that the minimal capacity of SEC can be achieved by an appropriate selection of excitation capacitor bank. With the help of instantaneous power theory, the control mechanism for the DWIG system working with a variable rotor speed is analyzed. Moreover, the system control strategy which is fit for the wide-speed-range operation using the stator flux orientation is consequently proposed. An 18-kW DWIG system with a 270-V high voltage DC output is developed. The simulation and experimental results illustrate a desirable performance, and the compact implementation of SEC is obtained.