Operation and Control of Microgrid

The demand for electricity is increasing day by day due to technological advancements. According to the demand, the size of the grid is also increasing rapidly in the past decade. However, the traditional centralized power grid has many drawbacks such as high operating cost, customer satisfaction, less reliability, and security. Distribution generation has less pollution, high energy efficiency, and flexible installation than traditional generation. It also improves the performance of the grid in peak load and reliability of supply. The concept of micro-grid has been raised due to the advent of new technologies and development of the power electronics and modern control theory. Micro-grid is the significant part of the distribution network in the future of smart grid, which has advanced and flexible operation and control pattern, and integrates distributed clean energy.

EMC Installation for Variable Speed Drive Systems (VSDs)

This chapter introduces EMC installation for variable speed drive systems. As an introduction, EMC standards have been mentioned in order to define the requirements characteristics, besides the fundamentals of static, electric, magnetic, and electromagnetic fields. Both inductive and capacitive coupling have been discussed to deal with shielding. Finally, VSDS emission and electromagnetic interferences were studied with installation requirement in VSDS (supply cables, cable between converter and motor, control cables, earthing requirements, and grounding).

Under Frequency Load Shedding Techniques for Future Smart Power Systems

It is critical for today's power system to remain in a state of equilibrium under normal conditions and severe disturbances. Power imbalance between the load and the generation can severely affect system stability. Therefore, it is necessary that these imbalance conditions be addressed in the minimum time possible. It is well known that power system frequency is directly proportional to the speed of rotation of synchronous machines and is also a function of the active power demand. As a consequence, when active power demand is greater than the generation, synchronous generators tends to slow down and the frequency decreases to even below threshold if not quickly addressed. One of the most common methods of restoring frequency is the use of under frequency load shedding (UFLS) techniques. In this chapter, load shedding techniques are presented in general but with special focus on UFLS.

Reliable Electricity Generation in RES-Based Microgrids

Using microgrid generation technologies is proposed in order to organize reliable power supply to rural areas. The concept of microgrid based on RES is considered as one of the realization forms of the distributed energy paradigm. In this chapter, there are the principles of generating complex formation in any given microgrid considering the specifics of the region, consumption patterns, and the potential of renewable energy sources in a given area. The algorithm for meeting the challenges of forming the structure of the microgrid generating structure is shown. The criteria for selection of power generation sources when solving the issue of their inclusion in the microgrid is proposed. The chapter also suggests the design of the micro gas turbine that is able to operate on biogas.

Synchrophasor-Based Wide Area Protection Scheme for System Stressed Conditions to Avoid Power System Blackout

Protection of transmission system is crucial for the secured and stable operation of power system. Under stress conditions, the operating parameters of power system violate their limits. From the past anatomy reports of several blackouts, it is clear that equipment, control, and protective relay failures are the major causes behind large power system failure. From study, it is also revealed that failure of back-up protection is more prone during system stressed conditions. In transmission system, third-zone of distance relay is highly affected by system stressed events such as voltage instability and load encroachment. As third-zone protection is a delayed protection scheme, with the help of wide area measurement system better protection function can be provided to reduce future percentage of blackout. In this chapter, a detailed discussion about the existing solutions is provided to mitigate the issue of system stressed conditions and a synchrophasor technology-based approach is provided. Results for different cases are provided to show the efficacy of the proposed method.

Operation of Microgrid and Control Strategies

Microgrids are the most innovative area in the electric power industry today. A microgrid can operate in grid-connected or islanded mode. In islanded mode, microgrids can provide electricity to the rural areas with lower cost and minimum power losses. Several methods have been proposed in the literature for the successful operation of a microgrid. This chapter presents an overview of the major challenges and their possible solutions for planning, operation, and control of islanded operation of a microgrid. Microgrids are the most innovative area in the electric power industry today. Moreover, microgrids provide local voltage and frequency regulation support and improve reliability and power capacity of the grid. The most popular among the control strategies based on droop characteristics, in addition a central controller is described within a hierarchical control scheme to optimize the operation of the microgrid during interconnected operation. Microgrid control methods, including PQ control, droop control, voltage/frequency control, and current control methods are formulated.

Power Quality and Stability Analysis of Variable-Speed Drive Systems (VSDS)

This chapter introduces an analysis of power quality of variable-speed drive systems (VSDS). In this chapter, several issues have been discussed as VSDS in terms of cost and effectiveness, VSDS control loops (open loop, closed loop), and power quality in VSDS. Harmonics standards and harmonics in VSDS were discussed in this chapter in addition to highlighting the effects of harmonics on power factor, crest factor, and other power quality specifications. The solutions used to mitigate the harmonics in VSDS were discussed in detail. Finally, simulation of the conventional VSDS model and VSDS with one harmonic mitigation solution in order to clarify the usefulness of using this solution on power quality specifications were discussed.

Management of Electrical Maintenance of University Buildings Using Deterioration Models

Buildings maintenance has received increasing international attention in various fields of scientific research. As a result, there has been a change in the maintenance of buildings from the preventive to the predictive approach. This is done through an evaluation model to support and assist the management of the facility in selecting alternatives and making appropriate decisions in maintenance according to building status and maintenance budget. This chapter investigated the reasons for the electrical maintenance of the university buildings and the degree of importance of each element of electrical maintenance through the design of a questionnaire in which the electrical components were divided into elements and then each element was linked to all maintenance items that related to it. At the end of the research, mathematical models were developed; these models help to forecasting the electrical maintenance items and distribution of the maintenance budget, and to verify the validity of these models, they have been applied to study the case of dorm buildings in Tishreen University.

Power Quality of Electrical Power Systems

Power quality problems can cause processes and equipment to malfunction or shut down. And the consequences can range from excessive energy costs to complete work stoppage. Obviously, power quality is critical. There are many ways in which a power feed can be poor quality, and so no single figure can completely quantify the quality of a power feed. In this chapter, the authors present all definitions, classifications, and problems related to power quality. Finally, they do a comparison between the practical measurements and standards related to power quality.

Issues Associated With Microgrid Integration

Microgrid (MG) is the vital technology that can be utilized to supply electricity to rural areas by fulfilling various aspects of electricity such as sustainability and reliability. Further, MG technology can also be used as localized generation sources and back up supply source. As MG can be worked in interconnected mode, various issues related to interconnection with utility grid are raised. Several issues such as technical, regulatory, and operational are associated with grid integration. Therefore, this chapter deals with the issues that are associated with the grid integration of microgrid.