Ramazan Bayindir

A water pumping control system with a programmable logic controller (PLC) and industrial wireless modules for industrial plants—An experimental setup

This paper describes a water pumping control system that is designed for production plants and implemented in an experimental setup in a laboratory. These plants contain harsh environments in which chemicals, vibrations or moving parts exist that could potentially damage the cabling or wires that are part of the control system. Furthermore, the data has to be transferred over paths that are accessible to the public. The control systems that it uses are a programmable logic controller (PLC) and industrial wireless local area network (IWLAN) technologies. It is implemented by a PLC, an communication processor (CP), two IWLAN modules, and a distributed input/output (I/O) module, as well as the water pump and sensors. Our system communication is based on an Industrial Ethernet and uses the standard Transport Control Protocol/Internet Protocol for parameterisation, configuration and diagnostics. The main function of the PLC is to send a digital signal to the water pump to turn it on or off, based on the tank level, using a pressure transmitter and inputs from limit switches that indicate the level of the water in the tank. This paper aims to provide a convenient solution in process plants where cabling is not possible. It also has lower installation and maintenance cost, provides reliable operation, and robust and flexible construction, suitable for industrial applications.

Fault Detection and Protection of Induction Motors Using Sensors

Protection of an induction motor (IM) against possible problems, such as overvoltage, overcurrent, overload, overtemperature, and undervoltage, occurring in the course of its operation is very important, because it is used intensively in industry as an actuator. IMs can be protected using some components, such as timers, contactors, voltage, and current relays. This method is known as the classical method that is very basic and involves mechanical dynamic parts. Computer and programmable integrated circuit (PIC) based protection methods have eliminated most of the mechanical components. However, the computer-based protection method requires an analog-to-digital conversion (ADC) card, and the PIC-based protection method does not visualize the electrical parameters measured. In this study, for IMs, a new protection method based on a programmable logic controller (PLC) has been introduced. In this method, all contactors, timers, relays, and the conversion card are eliminated. Moreover, the voltages, the currents, the speed, and the temperature values of the motor, and the problems occurred in the system, are monitored and warning messages are shown on the computer screen. Experimental results show that the PLC-based protection method developed costs less, provides higher accuracy as well as safe and visual environment compared with the classical, the computer, and the PIC-based protection systems.

A Remote Laboratory Experiment for 4-Quadrant Control of a DC Motor

This study presents development of the system architecture to perform laboratory experiments over the Internet for electrical engineering education. Design and implementation of four‐quadrant speed control experiment for a direct current (DC) motor is given in the article as a sample remote experimental study. The system designed consists of four main parts as a client, a server, a data acquisition unit and an experimental set with a control unit. MATLAB web server (MWS) is used to send and receive data or graphics over the Internet. While the experiment is being operated, the real experimental set placed in the laboratory can be monitored by the remote user. Evaluation results show that the system designed accelerates the learning period, increases the concentration on the experiment and provides a safe environment for four‐quadrant speed control experiment of a DC motor.

The design and analysis of a 5-level cascaded voltage source inverter with low THD

Multilevel inverters have been important devices developed in recent years, owing to their capability to increase the voltage and power delivered to the load. Researches done based on basic inverter topologies show that, multilevel inverters have many advantages such as low power dissipation on power switches, low harmonic and low electromagnetic interference (EMI) outputs. A modified Sinusoidal Pulse Width Modulation (SPWM) modulator that reduces output harmonics is presented in this paper. The proposed modulation technique can be easily applied to any multilevel inverter topology carrying out the necessary calculations. The most common multilevel inverter topologies have been studied to define the best topology for SPWM modulation strategy. It is seen that cascaded H-bridges are the most convenient solution. The cascaded H-bridge cells have been constituted by IGBT semiconductors, and switched by the proposed 24-channel SPWM modulator to obtain 5-level output at the back-end of the 3-phase voltage source inverter (VSI). The designed H-bridge cells have a strong switching bandwidth up to 40 KHz, owing to its robustly designed modulator block. The proposed VSI in this paper also has a Total Harmonic Distortion ratio of output current (THDi) around at 0.1% without requiring any filtering circuit. The harmonic analysis of proposed design has been executed under several working conditions such as various switching frequencies and modulation indexes. The detailed comparisons have been performed to determine the best working conditions of VSI and presented in this paper.

Reactive power compensation using a fuzzy logic controlled synchronous motor

This paper introduces the use of a fuzzy logic controlled synchronous motor for reactive power compensation. The fuzzy logic controlled synchronous motor can give a very fast response to the reactive power required by the load. Therefore, the over or under compensation and time delay are eliminated in this system. It is concluded that the reactive power compensation system with a fuzzy logic controlled synchronous motor is reliable, sensitive, economical, faster and more efficient than an other one with capacitor groups.

Design and analysis of a 7-level cascaded multilevel inverter with dual SDCSs

Multilevel inverters with a large number of steps can generate high quality voltage waveforms, good enough to be considered as suitable voltage source generators. A modified Sinusoidal Pulse Width Modulation (SPWM) modulator with phase disposition that increases output waveform up to 7-level while reducing output harmonics is presented in this paper. The proposed modulation technique can easily be applied to any multilevel inverter topology carrying out the necessary calculations. The modulator block is designed to control multilevel inverter that is constituted using dual H-bridge cells with IGBTs on each phase legs. The supply voltages of cells are defined at Vdc÷2Vdc ratio to obtain an asymmetrical output. The output waveform of asymmetrical topology is increased up to 7-level by using dual separate DC sources (SDCSs). The DC supply requirement of asymmetrical cascaded topology is solved using dual sources instead of 6 SDCSs. The cascaded multilevel inverter is switched by the proposed 24-channel SPWM modulator. The harmonic analysis of proposed inverter has been performed under several working conditions such as various switching frequencies and modulation indexes. The detailed comparisons are performed to determine the best working conditions of voltage source inverters (VSI) and presented in this paper.

Microgrid test-bed design with renewable energy sources

This paper is dedicated to microgrid design by using several renewable energy sources (RES) together. The generator side contains the most widely used three types of RESs that are wind energy, solar energy, and fuel cells. The wind turbine is designed according to parameters of a 6.5kW commercial permanent magnet synchronous generator (PMSG). The solar plant that has 15kW rated power is constituted with string connection of 96 solar panels that has 170Wp rated power for each. The last generator of system is modelled according to parameters of a fuel cell that generates 10.5kW peak power. All the generation units are coupled over dc bus-bar by adjusting the voltages to 48Vdc. The dc loads are directly connected to bus-bar while the ac loads are supplied by ac bus-bar that is built by a three-phase 48V/380V-50Hz inverter. An RLC load with 10kW/250VA/250VAR power is connected to the output of inverter. The proposed test-bed can be improved by adding several generator and load types, and additional controllers, breakers, and contactors. In its current state, the proposed test-bed is considered as a preliminary design.

Hybrid microgrid testbed involving wind/solar/fuel cell plants: A desing and analysis testbed

This study introduces design, integration, control, and analysis of a hybrid microgrid (MG) testbed including a 300 kW wind energy plant of three 100-kW permanent magnet synchronous generators (PMSGs), 50 kW solar energy plant of 200 solar panels, and a 50 kW fuel cell stack. Generation side of the hybrid plant coupled on 120V dc bus where wind energy plant consists of uncontrolled diode rectifier and dc-dc buck converter rail while the solar and fuel cell plants are just controlled by dc-dc buck converters. The energy conversion of solar energy plant is operated by using proportional-integral (PI) controller assisted perturb and observe (P&O) maximum power point tracking (MPPT) algorithm. The dc-dc converters of the left generators are operated with PI controllers. All the dc-dc converters are constituted with mosfets that are switched at 30 kHz. The islanded AC grid of the plant is built by three-phase inverter that generates 480 V 60 Hz industrial voltages of the U.S. The inverter is operated by a sinusoidal pulse width (SPWM) modulator where the modulation index is set to 0.8 and switching frequency to 5 kHz. The proposed testbed is assumed essential to test and validate several case studies in terms of MG and renewable energy source integration issues. The most recent power control methods (PQ) and amplitude controls (V-f) can also be implemented by using the presented testbed.

A modified harmonic mitigation analysis using Third Harmonic Injection PWM in a multilevel inverter control

A modified Third Harmonic Injection PWM (THI-PWM) modulator that reduces output harmonics has been presented in this paper. The modulator is combined with harmonic injection and phase shifting parts in Simulink design. The harmonic injection ratios have been analysed according to harmonic amplitude ratio of third harmonic to fundamental amplitude. The designed modulator is capable to minimize the injected harmonic ratio in order to increase the modulation index over 1.15 limit of regular THI-PWM control scheme. The proposed VSI in this paper supplies 7-level line voltages and 0.25% THDi ratio at 5 kHz while the modulation index is 1.2.

Microgrid facility at European union

The global microgrid market is promptly flourishing as government and private sector willingly to support actively. Todays, many countries and government have encouraged installing renewable energy farms for example wind farms and solar farms etc., and huge research has started in various aspect of it at the university level. The energy market in the United States is the largest market which has already taken a clear lead and they have mainly focused on remote microgrid and military microgrid. In European Union region, microgrids have reached in mature technology to participate in utility grid. However, in Asia-Pacific and Far East region has huge potential to grow up renewable energy market in future due to emerging economies to overcome power shortages/power outages and low grid connectivity. This paper presents several distributed generation around the European Union region and we have tabled testbeds information together. It helps the researcher to visualize todays microgrid and insight perceiving the possible evolvement of future grid. The study has concluded emphasizing the remarkable findings and potential research areas that would enhance for microgrid facilities.