The impact of variable renewable energy resources on power system reliability

Uncertainty parameters of battery energy storage integrated grid and their modeling approaches: A review and future research directions

Power system is one of the most complex systems ever designed. Determining its reliability is therefore a demanding process, which is mostly dealt with in a way that partial problems are stated and solved. A reliability method of loss of load expectation is selected and improved and the model of conventional power system is considered as a standpoint. Reliability of the initial conventional power system is evaluated. Then, the conventional power system is changed, where one conventional power plant is abandoned and new wind power plants stand to its place. The reliability of the initial and the changed power system is calculated and compared. Discussion shows the problems of decreased reliability of the power system with increasing the percentage of wind power plants within the power system replacing conventional plants, if not enough reserve is added to the power system at the same time. The other related problems are discussed in addition, to show that the problem is very complex and one cannot only consider a limited number of influencing parameters when deciding on power system configurations.

Guest Editorial: Situational awareness of integrated energy systems

In the power system of the future, reliability will play an important role. This reliability is influenced by different developments like the increase in electricity consumption and the use of renewable and distributed generation. It is important to have a good insight into the reliability performance of the system. With probabilistic methods, the reliability of the power system can be analyzed and decisions can be made to maintain the high reliability level that we demand. This paper gives an overview of the different developments in power systems and describes how these developments influence the reliability of the future power system. The possibilities to implement these developments into the probabilistic reliability analysis in network planning and operational planning are discussed. By use of an example, the possibilities and challenges of probabilistic methods in operational planning are illustrated.

The reliability of power system will obviously be influenced by wind farms connected because of the volatility of wind power. With the increase of wind power penetration, it's necessary to research the influence of wind power integration on the reliability level of system and how much reserve capacity should we increase in order to stabilize the influence of wind power on power system reliability. In this paper a reliability evaluation model is built by Monte Carlo method and also a reserve optimization model, which can be used to analyze changes of system reliability in conditions of different grid-connected wind farms, and to find out the optimum of system reserve to achieve unifying the maximum utilization of new energy and meanwhile high reliability of power system.

Small power systems such as those found on offshore platforms are fragile; yet, they must operate reliably for economy and safety for personnel and the environment. These systems often include combustion turbine generators for main process power requirements and black-start diesel generators that can supply essential and emergency buses and be used to restart the main generation in the event of a power system collapse. The power distribution systems on these offshore platforms have built-in redundancy with multiple circuits to supply critical loads for fault tolerance and operating flexibility. A system to easily and safely synchronize islanded buses via many possible synchronization points can revolutionize the operational flexibility and therefore the safety and reliability of the power system. This paper reports on advanced synchronizing systems installed on two offshore platforms.

In recent years, the adoption of electric vehicles (EVs) and variable energy resources such as photovoltaic (PV) has increased with the desire to reduce reliance on fossil fuels, decrease emissions, and promote sustainable energy. However, the increasing adoption of EVs and PVs has introduced unprecedented challenges to the reliability of power systems. The challenge lies in the inherent intermittency associated with solar generation and the uncertainty introduced by the charging load of EVs on the demand side of power grids. Therefore, it is indispensable from the perspective of power system operation and planning to consider the uncertainties associated with the output power of these resources in the reliability assessment framework. This paper develops an electric vehicle load model considering diverse charging station locations, EV types, and drivers' behavior. Also, the proposed method integrates the uncertainty of PV generation through interval prediction utilizing the K-Nearest Neighbors regressor. A sequential Monte Carlo simulation is used to analyze the impact of PV interval (forecasted lower and upper generation profile), EV load (hourly and peak), line failures, and demographic characteristics associated with EV on power system reliability. The reliability assessment is extended to sensitivity analysis and evaluation of the impact of EV loads and PV generation profiles on the capacity value of PV generators with different capacities, utilizing the Discrete Convolution approach. The proposed approach is demonstrated on the IEEE Reliability Test System and the results show the effectiveness of the proposed approach in determining the reliability of the power system by explicitly accommodating PV uncertainties and the intricacies of EVs.

A multi-objective fuzzy robust optimization approach for designing sustainable and reliable power systems under uncertainty

Reliability and economic evaluation of power system with renewables: A review

A review of power system planning and operational models for flexibility assessment in high solar energy penetration scenarios

Three-parameter interval number theory and its application in power system reliability evaluation

Chapter 28 - Optimal power generation and power flow control using artificial intelligence techniques

In electric power systems, the generated power should be equal with the demand and power of network is mainly controlled through generation system. In such operation, the demand is satisfied through changing the generated power and afterward, the safe operation of power system is reached. But during recent years, a new concept has been developed in electric power systems namely demand side management (DSM). DSM is the modification of consumer demand for energy through various methods such as financial incentives and education. Usually, the goal of demand side management is to encourage the consumer to use less energy during peak hours, or to move the time of energy use to off-peak times such as nighttime and weekends. One of the important models of DSM is interruptible loads. Interruptible loads are the right for an electricity utility to interrupt supply to a customer, typically during a system emergency, to relieve short term network constraints up to a couple of hours. Interruptible loads can be deployed in one of two ways. The network operator gives notice of an interruptible load event to the customer, then relies on the customer to reduce their electricity usage; or unilaterally interrupts supply to the customer. In this paper, the effect of interruptible loads on the power system reliability is investigated. A multi machine power system is considered as cases study. Simulation results show the great effects of interruptible loads on the power system reliability.

Installing new power generation unit always effects operation and performance of a power system including balance between load and generation. Consequently, demand for power reserves the power balancing authority has to acquire for keeping the power system in the equilibrium is changing. Restructuring power system in terms of shutting down old generation units, installing new ones or changing operational characteristics of the existing units will result in different needs for the amount and dynamics of power reserves in the respective categories. The paper studies the situation when the portfolio of power generation units is planned to be changed, new units are going to be installed and some old ones shut down. The effect on power system reliability and change in demand for ancillary services (AS) which are needed to meet the reliability standards is analyzed. Power system reliability is expressed in terms of reliability indices as used by the Czech TSO. Two scenarios of future development of power unit portfolio differ in number and capacity of new units. Finally the impact of new units on AS reservation cost is shown and discussed.

Review on hybrid geothermal and solar power systems