Due to the rising infiltration of renewable energy sources, it is indispensable to investigate its brunt on the optimal power generation scheduling. However, the highly intermittent nature of renewable energy sources and their higher rate of outages may harm the entire grid. This work recommends fast convergence evolutionary programming (EP) with a time-varying mutation scale (FCEP_TVMS) for solving fixed head hydrothermal scheduling incorporating pumped-storage-hydraulic unit with demand-side management considering the uncertainty and outage of renewable energy sources. Simulation outcomes of the test system have been matched up to those acquired by fast convergence EP, colonial competitive differential evolution and heterogeneous strategy particle swarm optimisation. It is seen from the comparison that the recommended FCEP_TVMS technique can give a better-quality solution.

The energy storage system is the backbone of an isolated microgrid (MG), which helps to provide a secure and reliable power supply. The operation of the MG systems operating without storage is affected highly due to intermittent generation and sudden load demand fluctuations. This study investigates the operational behaviour of an isolated MG system in terms of frequency and power balance by incorporating the Micro Pump Hydro Energy Storage (MPHES) system. The investigated MG system consists of biodiesel, solar and wind-based generating units with MPHES and battery as energy storage systems. The realistic data for solar and wind resources have been used to consider the practical scenario of any area. The recently developed coyote-optimisation algorithm is employed for optimal tuning of the proportional–integral controller using the integral of time multiplied absolute error criterion. The simulation studies have been conducted to investigate the performance of the MG system by incorporating the MPHES system for a typical day (36 h) under various operating conditions. The analysis reveals that the MG system exhibits smoother and consistent dynamic performance by including the MPHES unit and efficiently utilises renewable power.

Unregulated distributed energy sources such as solar roofs and windmills and electric vehicle requirements for intermittent battery charging are variable sources either of electricity generation or demand. These sources impose additional intermittent load on conventional electric power systems. As a result thermal power plants whose generation is absolutely essential for any power system are increasingly being used for cycling operations thus increasing greenhouse gas emissions and electricity cost. The use of secondary energy storage might be a solution. Various technologies for storing electric energy are available; besides electrochemical ones such as batteries, there are mechanical, chemical and thermal means, all with their own advantages and disadvantages regarding scale, efficiency, cost, and other parameters. This classic book is a trusted source of information and a comprehensive guide to the various types of secondary storage systems and choice of their types and parameters. It is also an introduction to the multidisciplinary problem of distributed energy storage integration in an electric power system comprising renewable energy sources and electric car battery swap and charging stations. The 3rd edition has been thoroughly revised, expanded and updated. All given data has been updated, and chapters have been added that review different types of renewables and consider the possibilities arising from integrating a combination of different storage technologies into a system. Coverage of distributed energy storage, smart grids, and EV charging has been included and additional examples have been provided. The book is chiefly aimed at students of electrical and power engineering and design and research engineers concerned with the logistics of power supply. It will also be valuable to general public seeking to develop environmentally sound energy resources.

Hybrid power stations (HPSs) are virtual power plants comprising storage and renewable energy source facilities operated in a coordinated manner as dispatchable stations. The HPS concept has been introduced as a means to increase renewable penetration in saturated island systems. The main objective of this study is to shed light on the operation of battery-based HPSs in small-island systems and their investment feasibility. Anticipated benefits for the island system are quantified in terms of system production cost and renewable penetration, while the exploitation of available renewable energy by the HPS is analyzed and the internal operation of its components is evaluated. A mixed integer linear programming generation scheduling approach is used to conduct daily and annual simulations of the entire island generation system, while at the same time optimising the internal management of the HPS as well. Based on the operating results thus obtained, the economic feasibility of battery-based HPS investments using wind, photovoltaics or their combination as the renewable generation component is assessed, by utilising the levelised cost of energy as the primary evaluation index and accounting for the life expectancy of the HPS battery storage system.

The authors intent using a boost multi-level converter for the doubly fed induction machine (DFIM) used in variable-speed pumped storage plants (VS-PSP). Voltage-source converters connected on the rotor side of the machine control the active and reactive powers of the unit. The proposed boost neutral point clamped (NPC) converter topology provides a voltage output two times larger than a conventional three-level NPC (3L-NPC) with similar DC-link voltage and equal number of switches. Hence, it increases the speed variation of the unit, which improves the efficiency during generation and pumping modes. Moreover, it reduces the starting period of the unit at the pumping mode, which is significant during mode changeover time. Furthermore, it reduces switching and conduction losses in the converter. It also reduces the total harmonic distortion in the output current, as it provides five output voltage levels. These improvements show that the boost NPC converter topology is better among VS-PSP project authorities. In addition, the reliability of the proposed topology is investigated, where converter redundancy is a challenging issue in asynchronous VS-PSP units. The proposed boost NPC was compared with the conventional 3L-NPC system by examining a 250 MW DFIM hydro-generating unit.

Growing trends in the deployment of inverter-based renewable energy will decrease the inertia and frequency control capability of electric power systems by replacing conventional power plants; thus, the frequency of future power systems might be dynamic. This study proposes a capability-coordinated frequency control (CCFC) scheme of a virtual power plant (VPP) including adjustable-speed pumped storage hydropower (AS-PSH), a wind power plant (WPP), and an energy storage system to support the frequency nadir and reduce the steady-state error of system frequency. The CCFC scheme is based on a hierarchical-control structure in which a CCFC organises the output of local frequency control units. To support the frequency nadir, the CCFC dispatches weighted frequency errors that are proportional to the available headroom of the units; thus, the errors are forwarded separately with a system frequency error to the primary control loop of each unit and thereby arrest the frequency nadir at a higher value than a system without the CCFC. To reduce the steady-state error of the system frequency, the CCFC determines a partial active power command by additionally feeding an integrator of the CCFC with a modified frequency error that depends on the unit with the largest control.

The wind and hydro technologies express a significant part of the electricity generation section. This study presents an optimal coordinated bidding strategy of wind, cascaded hydro generation, and pumped-storage (PS) units. One of the chief purposes of this study is maximisation the profit of the wind and hydro plants by participating in the day-ahead energy and ancillary service markets. The regulation and spinning reserve markets are regarded as ancillary services. Thanks to the inherent variability and uncertainty of wind power, it does not participate in the ancillary service market. Hydro company is constructed of several cascaded hydro units which design alongside a river basin as well as a PS unit. In this study, the risk is modelled by using conditional value at risk. To reach the optimum solution, a new improved clonal selection algorithm is applied which shows the effectiveness of the proposed method for optimising a generation companies (GENCOs) profit.

As the large-scale wind power penetration and distributed generation become popular in modern power systems, the governing control of pumped storage unit has attracted many attentions in recent years for its flexible power adjustment capability. To provide a research platform for dynamic analysis of the hybrid power system, a micro-grid mainly including a pumped storage unit and a wind power plant is introduced in detail and taken as the system plant. Refined mathematical models of pump turbine, synchronous generator and wind turbine generator have been established considering the complicated non-linear dynamic characteristics of the multi-energy power system. Furthermore, a novel chaotic grey wolf optimiser algorithm is proposed to select the optimal control parameters of the pump turbine governing system for the sake of maintaining frequency stability and enhancing control performances under the complicated operating conditions. Simulation experiments have been conducted in the micro-grid under representative operating conditions to validate the effectiveness of the proposed control method and its preponderance in comparison with traditional ones.

Hydropower is a mature and cost-competitive renewable energy source, contributing the bulk of global renewable electricity. Over the past decades, computer technology has led to significant possible improvements in monitoring, diagnostics, protection and control through retrofitting of large plants, and there is potential for additional large plants as well as for smaller installations. This book presents a systematic approach to mathematical modeling of different configurations of hydropower plants over four sections - modeling and simulation approaches; control of hydropower plants; operation and scheduling of hydropower plants, including pumped storage; and special features of small hydropower plants. The chapters address the fundamentals and the latest concepts, providing the most appropriate solutions for cost-effective and reliable operation, and include several real-world case studies of hydropower plants in operation. Modeling and Dynamic Behaviour of Hydropower Plants is essential reading for researchers involved with hydropower, as well as for advanced students in power engineering.

The intermittency and variability of various renewable energy resources, such as wind power and photovoltaic solar energy, can overcome with the use of these resources in conjunction with energy storage devices. The energy storage as hydraulic power, so before energy conversion, can guarantee high efficiency to the storage process. This study aims to identify the technical and economic feasibility of using wind power and PV modules in conjunction with a reversible hydroelectric power plant installed in Aparados da Serra, in the south of the Serra Geral, a geological structure in southern Brazil that allows topographical height differences of approximately 600 m. In this work, specifically, a hydropower plant installed at Linha Sete with 610 kW and at 400 m height. This study explores the feasibility of this pumped storage plant operating in conjunction with existing wind turbines and PV modules installed on the surface of reservoirs. The work is based on simulations and optimization performed with well-known software HOMER. The results indicate that a group of 10-50 2-MW wind turbines may have an increased capacity factor from usual 0.34 to values between 0.50 and 0.60. The results also relate the power capacity and costs per kW installed for PV modules to be feasible. This work also indicates useful conclusions in the design process and implementation of the hybrid system under study.