Solid-state switch-mode rectification converters have reached a matured level for improving power quality in terms of power-factor correction (PFC), reduced total harmonic distortion at input AC mains and precisely regulated DC output in buck, boost, buck-boost and multilevel modes with unidirectional and bidirectional power flow. This paper deals with a comprehensive review of improved power quality converters (IPQCs) configurations, control approaches, design features, selection of components, other related considerations, and their suitability and selection for specific applications. It is targeted to provide a wide spectrum on the status of IPQC technology to researchers, designers and application engineers working on switched-mode AC-DC converters. A classified list of more than 450 research publications on the state of art of IPQC is also given for a quick reference.

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A review of single-phase improved power quality AC-DC converters

http://www.paredox.com/foswiki/pub/Luichart/RedoxTechnicalPapers/Battery_energy_storage_technology_for_power_systemsAn_overview.pdf

Battery Energy Storage Technology for power systems-An overview

Due to the stochastic nature of wind, electric power generated by wind turbines is highly erratic and may affect both the power quality and the planning of power systems. Energy Storage Systems (ESSs) may play an important role in wind power applications by controlling wind power plant output and providing ancillary services to the power system and therefore, enabling an increased penetration of wind power in the system. This article deals with the review of several energy storage technologies for wind power applications. The main objectives of the article are the introduction of the operating principles, as well as the presentation of the main characteristics of energy storage technologies suitable for stationary applications, and the definition and discussion of potential ESS applications in wind power, according to an extensive literature review.

A review of energy storage technologies for wind power applications

Lithium-ion-based battery energy storage system has started to become the most popular form of energy storage system for its high charge and discharge efficiency and high energy density. This paper proposes a high-efficiency grid-tie lithium-ion-battery-based energy storage system, which consists of a LiFePO4-battery-based energy storage and a high-efficiency bidirectional ac-dc converter. The battery management system estimates the state of charge and state of health of each battery cell and applies active charge equalization to balance the charge of all the cells in the pack. The bidirectional ac-dc converter works as the interface between the battery pack and the ac grid. A highly efficient opposed-current half-bridge-type inverter along with an admittance-compensated quasi-proportional resonant controller is adopted to ensure high power quality and precision power flow control. A 1-kW prototype has been designed and implemented to validate the proposed architecture and system performance.

/pdf/a-high-efficiency-grid-tie-battery-energy-storage-system-3fllpt0asp.pdf

A high-efficiency grid-tie battery energy storage system

Nonlinear differential-geometric techniques are proposed for the design of a feedback controller for three-phase voltage-source pulsewidth modulation (PWM) AC/DC boost converters under a cascade control structure. The input-output linearizability of the system modeled in d-q synchronous reference frames is examined. The results lead to a decoupled d-q current control scheme. For the internal DC-bus voltage dynamics (zero dynamics), by considering the d-axis current command as control input and using a square transform on DC-bus voltage, it is shown that this remaining system contains an input memoryless nonlinearity of conic sector type and satisfies the conditions for a Lur'e plant. This suggests a new outer-loop control strategy to control the square of the DC output voltage, rather than DC output voltage itself, utilizing a simple proportional plus integral (PI) controller cascaded to the d-axis current loop. Since most results do not consider the control of zero dynamics, the strategy for the control of zero dynamics via cascade control structure may provide valuable insight for the design of input-output linearized systems in which zero dynamics contain some desired control variables. The absolute tracking concept for Lur'e plants is introduced to prove the global tracking capability with zero steady-state error of the voltage loop. The controlled PWM AC/DC converter has the features of global stability, fast (exponential) tracking of DC-bus voltage command with zero steady-state error, asymptotic rejection of load disturbance, robustness against parameter uncertainties and decoupled dynamical responses between d and q current loops. Also, measurement of load current is not required. All these features are confirmed via laboratory experiments on a 1.5 kVA PC-based controlled prototype.

Input-output linearization and zero-dynamics control of three-phase AC/DC voltage-source converters

This paper presents a three-phase pulsewidth modulated AC-to-DC power converter with unity power factor and near-optimum dynamic regulation. A general mathematical model of the converter has been established to lead to a comprehensive analysis. The averaged small-signal technique is used to obtain the near-optimum feedforward compensator, thus resulting in the output impedance, and the audio susceptibility become zero, that is, the output voltage of the converter presented in this paper is independent of variations of the DC load current and the utility voltage. The proposed procedure of analysis is simple and effective, and it is also easy to implement. Finally, the theoretical formulations are verified both by simulated and experimental results in a 5 kW laboratory prototype system.

Analysis and design of three-phase AC-to-DC converters with high power factor and near-optimum feedforward

This paper presents a new control strategy in a battery energy storage system (BESS) for multifunction operation. The multifunction BESS operates in two modes: one is the parallel processing mode which can play as an active filter, a power conditioner, or a voltage stabilizer; and the other is the stand-alone mode which acts as a conventional uninterruptible power supply. Basic principle from the conventional control method is used and modified to accomplish the desired operation function. The proposed theoretical formulations are verified by system analysis and simulation to present its performance. A laboratory prototype is fabricated and tested to support the proposed idea of a multifunction battery energy storage system.

Design and implementation of a demand-side multifunction battery energy storage system

I I Abstract-This paper presents a new control strategy in a battery energy storage system (BESS) for multifunction opera- tion. The multifunction BESS operates in two modes: one is the parallel processing mode which can play as an active mter, a power conditioner, or a voltage stabilizer; and the other is the stand-alone mode which acts as a conventional uninterruptibk power supply. Basic principle from the conventional control method is used and modified to accomplish the desired operation function. The proposed theoretical formulations are verified by system analysis and simulation to present its performance. A laboratory prototype is fabricated and tested to support the proposed idea of a multifunction battery energy storage system.

Wen-Inne Tsai

Papers

Analysis and design of three-phase AC-to-DC converters with high power factor and near-optimum feedforward

Design and implementation of a demand-side multifunction battery energy storage system

lementation of a Demand-Side tifunction attery Energy Storage System