Ali Mazloomzadeh

Laboratory-Based Smart Power System, Part I: Design and System Development

This paper presents the design and development of a hardware-based laboratory smart grid test-bed. This system is developed at the Energy Systems Research Laboratory, Florida International University. The hardware/software based system includes implementation of control strategies for generating stations, and power transfer to programmable loads in a laboratory scale of up to 35 kilowatts in ac power and 36 kW in renewable sources and energy storages. Appropriate software was developed to monitor all system parameters as well as operate and control the various interconnected components in varying connectivity architectures. The interconnection of alternate energy such as wind emulators, PV arrays, and fuel cell emulators are implemented, studied and integrated into this system. Educational experiences were drawn during the design and system development of this laboratory-based smart grid. The real-time operation and analysis capability provides a platform for investigation of many challenging aspects of a real smart power system. The design, development, and hardware setup of this laboratory is presented here in Part I of this paper. This includes component development, hardware implementation, and control and communication capabilities. Part II of the paper presents the implementation of the monitoring, control, and protection system of the whole setup with detailed experimental and simulation results.

Laboratory-Based Smart Power System, Part II: Control, Monitoring, and Protection

Wide area monitoring (WAM), wide area protection (WAP), and wide area control (WAC) systems will enhance the future of smart grid operation in terms of reliability and security. In part I of this paper, a proposed architecture for a hybrid ac/dc smart grid hardware test-bed system was presented. Design details of the various components and their connectivity in the overall system architecture were identified. In part II of the paper, the focus is on the design of monitoring, control, and protection systems and their integrated real-time operation. Various control scenarios for system startup and continuous operation are examined. We have developed a control system based on wide area measurements. The advanced measurement system based on synchrophasors was also implemented using DAQs real-time synchronous data. The developed system features a wide variety of capabilities such as online system parameters calculation and online voltage stability monitoring. These are implemented as an experimental case to enhance wide area monitoring systems. Moreover, the protection system was designed inside of the real-time software environment to monitor the real-time wide area data, and make a comprehensive and reliable coordination for the whole system. Ideas related to the interaction of a dc microgrid involving sustainable energy sources with the main ac grid have been also implemented and presented. The implemented system is explicit and achievable in any research laboratory and for real-time real-world smart grid applications.

Development and implementation of a phasor measurement unit for real-time monitoring, control and protection of power systems

Measurement and calculations of actual power system parameters in real-time have been carried out by Synchronized Phasor Measurement Units (PMUs). The applications of PMUs in power system are extended to protection, control and monitoring of wide area of power system. This research will present the real-time calculation of power system parameters using PMUs and their application in power system studies. The developed system has the capability of utilizing the designed PMU for analyzing the power system in real-time. A laboratory test setup was utilized to test real-time application of the developed PMU. This system uses different DAQs to gather voltage and current data, and measure power system parameters such as the voltage and current phasors, positive, negative and zero sequences, powers and frequency of each component. The results of PMUs were verified by measurement devices. The potential of the developed PMU system in calculating the power system stability index in real-time as well as the line parameters by the available phasors data was discussed.

Fault Diagnosis of the Asynchronous Machines Through Magnetic Signature Analysis Using Finite-Element Method and Neural Networks

Summary form only given. This paper presents a method for the identification of winding failures in induction motors. The types of failures include unbalanced currents flowing into the motor and short-circuit of the winding. The radiated magnetic field of a typical induction motor was studied while various types of failures applied to the machine. The implementation was performed by applying different types of unbalanced currents flow into the machine. The fields were obtained from both numerical finite-element simulations as well as from experimental setups. The turn to terminal and turn to turn short-circuit of the motors winding were studied. The frequency response of the 3-D finite-element (3DFE) model of the motor was implemented up to high-order frequencies. The numerical results were compared with the measurement results. The fields with unbalanced currents and short-circuit conditions were identified by studying the harmonic orders of the radiated magnetic fields. This was also implemented using artificial neural networks (ANN). The results show that the signature study of the experimental as well as the simulation models can be utilized for failure identification in electric motors with a high level of accuracy.

Real-time analysis for developed laboratory-based smart micro grid

The modern power network incorporates communications and information technology infrastructures into the electrical power system to create a smart grid. The smart grid will utilize digital information technology to create a more efficient, reliable, flexible and responsive network. The objective of this paper is to apply the concept of real time analysis in a smart grid by developing a test-bed smart grid in power system laboratories. The laboratory experiment and analysis guarantee a high level of reliability when the smart grid is implemented in the actual field. Educational application of the laboratory-based smart grid and its real-time analysis capability, provide the platform for investigation of the most challenging aspects of real power system.

Islanding detection using synchronized measurement in smart microgrids

This paper presents the issues involved in the detection of islanding via traditional methods as well as the implementation of 3-phase synchronized measurements. A proposed technique for better islanding recognition in microgrids using multiple PMUs was developed. A new method which uses 3 phase synchronized measurements was introduced for the detection of unbalanced or partial islanding of microgrids. This occurs when the microgrid loose only one phase of its link to the main grid. In addition to simulation of the proposed method in MATLAB/Simulink, experimental results are also obtained. A small scaled 3-phase power system at the laboratory scale was developed and used to compare the traditional and new techniques. The comparisons of experimental and simulation results show that the proposed technique was successfully verified.

Real-time power system analysis and security monitoring by WAMPAC systems

The outline of this paper is to implement real-time analysis and security monitoring in the smart power system. Security is the ability of the power system to withstand contingencies. The principal role of Wide Area Monitoring, Protection and Control (WAMPAC) system is to maintain a secure system state, i.e. the system that can withstand each specified contingency. The advanced WAM system uses real-time measurements to monitor system status and hence determines whether or not it is secure. The WAMPAC system is used to deploy proper control actions on load, transmission and generation in a wide time frame from fast protection systems to slower control of generators. This paper also explores the challenges and opportunities to implement online system analysis capability in order to monitor system security and stability indices. Therefore, the implemented hardware/software setup for monitoring and analyzing system in real-time format will be presented by the online results available with real-time software. Online load flow and contingency results aim to proper security monitoring of power system in wide area which is useful for most application such as system remedial actions.

Development and evaluation of a laboratory based phasor measurement devices

In this paper, the development of a laboratory based phasor measurement unit (PMU) is presented. The developed PMU complies with the technical requirements of C37.118 synchrophasor standard and provides large number of time-synchronized measurements for a variety of laboratory based smart grid experiments. The prototype implementation was tested, evaluated and compared with commercial PMUs available at the smart grid test bed at Florida International University. The actual GPS antenna and receiver were used to provide standard timing (IRIG-B) signal. Through the developed embedded IRIG-B decoder, the trigger instance was retrieved. The deployed time information was used to trigger data acquisitions and consequently, to time-stamp the measurements such as frequency and voltage phasors. Finally, the collected information messages were reported to the phasor data concentrator (PDC) using synchrophasor protocol and compared with commercial PMUs. The results compare accurately and provide the user to implement a variety of test cases and training data to teach the many uses of PMUs.

Soft synchronization of dispersed generators to micro grids for smart grid applications

Fast and proper synchronization of generation stations is becoming inevitable specially in micro grids. Increased number of small generation units raised total quantity of their synchronization process to the micro grids. This Paper provides improvements in synchronization between an emulated power system and its power generation stations in a laboratory scaled power grid. Three methods including duty cycled control of torque controlled prime movers, with and without local load at generator terminal, and implementation of a dynamic load brake controller have been discussed for providing the proper conditions for synchronization. Finally experimental results for such methods in a real time power system test bed have been compared.

Comparative analysis of energy control techniques for DC microgrid and pulsed power load applications

DC Microgrid power systems are becoming increasingly common in many applications. In this work, the comparative analysis of different energy control techniques for a dc microgrid with pulsed power loads is considered. A laboratory scale hybrid dc microgrid is developed to evaluate the performance of the energy control methods. In the proposed dc microgrid, a supercapacitor bank, acting as power buffer, and a pulse load are directly connected to a common coupling dc bus while the injected power to the grid is regulated through power converters. This microgrid is connected to an AC grid test-bed to further analyze the consequence of the pulse loads. The test results show that the energy control methods are different in terms of their maximum power requirement, their performance on the dc microgrid, and their effects on the ac grid.