skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A flexible active and reactive power control strategy for a variable speed constant frequency generating system

Abstract

Variable-speed constant-frequency generating systems are used in wind power, hydro power, aerospace, and naval power generations to enhance efficiency and reduce friction. In these applications, an attractive candidate is the slip power recovery system comprising of doubly excited induction machine or doubly excited brushless reluctance machine and PWM converters with a dc link. In this paper, a flexible active and reactive power control strategy is developed, such that the optimal torque-speed profile of the turbine can be followed and overall reactive power can be controlled, while the machine copper losses have been minimized. At the same time, harmonics injected into the power network has also been minimized. In this manner, the system can function as both a high-efficient power generator and a flexible reactive power compensator.

Authors:
 [1];  [2]
  1. Electrical Motors, St. Louis, MO (United States). Emerson Motor Technology Center
  2. Ohio State Univ., Columbus, OH (United States). Dept. of Electrical Engineering
Publication Date:
OSTI Identifier:
131597
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Transactions on Power Electronics; Journal Volume: 10; Journal Issue: 4; Other Information: PBD: Jul 1995
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY; 13 HYDRO ENERGY; HYDROELECTRIC POWER PLANTS; POWER FACTOR; CONTROL; WIND POWER PLANTS; ENERGY EFFICIENCY; PERFORMANCE; INDUCTION GENERATORS

Citation Formats

Tang, Y., and Xu, L.. A flexible active and reactive power control strategy for a variable speed constant frequency generating system. United States: N. p., 1995. Web. doi:10.1109/63.391945.
Tang, Y., & Xu, L.. A flexible active and reactive power control strategy for a variable speed constant frequency generating system. United States. doi:10.1109/63.391945.
Tang, Y., and Xu, L.. 1995. "A flexible active and reactive power control strategy for a variable speed constant frequency generating system". United States. doi:10.1109/63.391945.
@article{osti_131597,
title = {A flexible active and reactive power control strategy for a variable speed constant frequency generating system},
author = {Tang, Y. and Xu, L.},
abstractNote = {Variable-speed constant-frequency generating systems are used in wind power, hydro power, aerospace, and naval power generations to enhance efficiency and reduce friction. In these applications, an attractive candidate is the slip power recovery system comprising of doubly excited induction machine or doubly excited brushless reluctance machine and PWM converters with a dc link. In this paper, a flexible active and reactive power control strategy is developed, such that the optimal torque-speed profile of the turbine can be followed and overall reactive power can be controlled, while the machine copper losses have been minimized. At the same time, harmonics injected into the power network has also been minimized. In this manner, the system can function as both a high-efficient power generator and a flexible reactive power compensator.},
doi = {10.1109/63.391945},
journal = {IEEE Transactions on Power Electronics},
number = 4,
volume = 10,
place = {United States},
year = 1995,
month = 7
}
  • As efforts are accelerated to improve the overall capability and performance of wind-electric systems, increased attention to variable speed configurations has developed. A number of potentially viable configurations have emerged. Various attributes of variable speed systems need to be carefully tested to evaluate their performance from the utility point of view. With this purpose, the NASA, experimental variable speed constant frequency (VSCF) system based on a design by F.R. Schleif has been tested. In order to determine the usefulness of these systems in utility applications, tests are required to resolve issues fundamental to electric utility systems. Legitimate questions exist regardingmore » how variable speed generators will influence the performance of electric utility systems; therefore, tests from a utility perspective have been performed on the VSCF system and an induction generator at an operating power level of 30 kW on a system rated at 200 kVA and 0.8 power factor.« less
  • The variable-speed, constant frequency generating system developed for the Mod-O wind turbine is presented. The development of this system occurred in several stages. This report describes the system as it existed at the conclusion of the project. The cycloconverter control circuit is described in detail. The major addition to the control circuit, field-oriented control, is also described. Laboratory test and actual wind turbine test results are included.
  • This paper discusses results of an EPRI contract on control design for an ac/dc transmission system to increase power transfers limited by dynamic stability. The control is achieved by modulating the rectifier dc current or power and the inverter dc voltage. Coordinated active and reactive power modulation is accomplished by Linear Quadratic (LQ) control design. Improved performance is realized by utilizing reactive power coupling between dc and ac networks to modulate dc and ac active power. For the demonstration system, power modulation with coordinated voltage modulation is shown to be about ten times more effective than power modulation alone. Controlmore » interactions between electromechanical modes of oscillation are eliminated by Kalman filtering. Filtering permits excellent control performance with a minimum of system measurements. Modern control technology is applied within realistic system constraints, such as measurements.« less
  • With increasing penetrations of wind generation on electric grids, wind power plants (WPPs) are encouraged to provide frequency ancillary services (FAS); however, it is a challenge to ensure that variable wind generation can reliably provide these ancillary services. This paper proposes using a battery energy storage system (BESS) to ensure the WPPs' commitment to FAS. This method also focuses on reducing the BESS's size and extending its lifetime. In this paper, a state-machine-based coordinated control strategy is developed to utilize a BESS to support the obliged FAS of a WPP (including both primary and secondary frequency control). This method takesmore » into account the operational constraints of the WPP (e.g., real-time reserve) and the BESS (e.g., state of charge [SOC], charge and discharge rate) to provide reliable FAS. Meanwhile, an adaptive SOC-feedback control is designed to maintain SOC at the optimal value as much as possible and thus reduce the size and extend the lifetime of the BESS. In conclusion, the effectiveness of the control strategy is validated with an innovative, multi-area, interconnected power system simulation platform that can mimic realistic power systems operation and control by simulating real-time economic dispatch, regulating reserve scheduling, multi-area automatic generation control, and generators' dynamic response.« less