Metin Kesler

Synchronous-Reference-Frame-Based Control Method for UPQC Under Unbalanced and Distorted Load Conditions

This paper presents a new synchronous-reference-frame (SRF)-based control method to compensate power-quality (PQ) problems through a three-phase four-wire unified PQ conditioner (UPQC) under unbalanced and distorted load conditions. The proposed UPQC system can improve the power quality at the point of common coupling on power distribution systems under unbalanced and distorted load conditions. The simulation results based on Matlab/Simulink are discussed in detail to support the SRF-based control method presented in this paper. The proposed approach is also validated through experimental study with the UPQC hardware prototype.

Vehicle-to-Grid Reactive Power Operation Using Plug-In Electric Vehicle Bidirectional Offboard Charger

The number of offboard fast charging stations is increasing as plug-in electric vehicles (PEVs) are more widespread in the world. Additional features on the operation of chargers will result in more benefits for investors, utility companies, and PEV owners. This paper investigates reactive power support operation using offboard PEV charging stations while charging a PEV battery. The topology consists of a three-phase ac-dc boost rectifier that is capable of operating in all four quadrants. The operation modes that are of interest are power-factor-corrected charging operation, and charging and capacitive/inductive reactive power operation. This paper also presents a control system for the PQ command following of a bidirectional offboard charger. The controller only receives the charging power command from a user and the reactive power command (when needed) from a utility, and it adjusts the line current and the battery charging current correspondingly. The vehicles battery is not affected during the reactive power operation. A simulation study is developed utilizing PSIM, and the control system is experimentally tested using a 12.5-kVA charging station design.

Single-Phase On-Board Bidirectional PEV Charger for V2G Reactive Power Operation

This paper presents the design and implementation of a single-phase on-board bidirectional plug-in electric vehicle (PEV) charger that can provide reactive power support to the utility grid in addition to charging the vehicle battery. The topology consists of two-stages: a full-bridge ac-dc boost converter; and a half-bridge bidirectional dc-dc converter. The charger operates in two quadrants in the active-reactive power (PQ) power plane with five different operation modes (i.e., charging-only, charging-capacitive, charging-inductive, capacitive-only, and inductive-only). This paper also presents a unified controller to follow utility PQ commands in a smart grid environment. The cascaded two-stage system controller receives active and reactive power commands from the grid, and results in line current and battery charging current references while also providing a stable dynamic response. The vehicles battery is not affected during reactive power operation in any of the operation modes. Testing the unified system controller with a 1.44 kVA experimental charger design demonstrates the successful implementation of reactive power support functionality of PEVs for future smart grid applications.

Power Converter-Based Three-Phase Nonlinear Load Emulator for a Hardware Testbed System

A three-phase nonlinear load emulator using a power electronic converter is presented in this study. The proposed nonlinear load emulator is intended to be used in an ultrawide-area grid transmission network emulator, also called hardware testbed (HTB). The emulator converter is controlled in rectifier mode to act as the real nonlinear three-phase diode rectifier load. This paper presents an accurate controller for the nonlinear load emulator based on a three-phase diode rectifier system to be used in the HTB. This study also demonstrates simulation and experimental results for verification of the proposed controller.

DSP based embedded code generation for PMSM using sliding mode controller

This study presents a Digital Signal Processor (DSP) based embedded code generation which is obtained automatically in PSIM software for Permanent Magnet Synchronous Motor (PMSM) control system. The simulation model of the PMSM control system is developed in PSIM environment using Motor Control Blocks and Embedded Target for TI 28335 block. This control block diagram is send to SimCoder to generate C-code that is ready to run on the DSP hardware, SimCoder also creates the complete project files for the TI Code Composer Studio development environment where the code will be compiled, linked, and uploaded to the DSP using High Voltage Motor Control-PFC Kit. So, embedded code generation provides a very quick way to design a motor drive system from user specifications also programming greatly simplifies the generation, prototyping and modification of DSP based design, thus decreasing the development cycle time.

Calculation of optimum fixed tilt angle of PV panels depending on solar angles and comparison of the results with experimental study conducted in summer in Bilecik, Turkey

Sunlight incidence angle varies throughout the year due to the rotation of the earth around its own axis and its elliptical orbit. While sunlight falls to the earth with steep angle in summer in the Northern Hemisphere, it falls with shallow angle in winter. Sunlight should fall with steep angle to extract maximum power from PV panels. Therefore optimum fixed tilt angles of PV panels should be changed monthly and seasonally. In the mathematical analysis of the study, the monthly, seasonal and the annual optimum fixed tilt angles of PV panels depending on solar angles are calculated for Bilecik city. In the experimental study, optimum fixed tilt angles for May, June, July and August are determined by PV panels placed at 10°, 20°, 30°, 40°, 50° and 60° tilt angles. The mathematical analysis results are compared with the experimental results.