Load modelling for generating capacity reliability evaluation using the frequency and duration method

Dynamic regulation reliability of a pumped-storage power generating system: Effects of wind power injection

RELIABILITY EVALUATION OF GENERATION SYSTEMS INCLUDING ENERGY LIMITED UNITS—A CLUSTER BASED APPROACH

A service-oriented architectural (SOA) model is proposed for power system reliability analysis especially for generating capacity adequacy evaluation. Generating system adequacy evaluation is performed to evaluate the ability of the system generating capacity to meet the total system demand. The proposed SOA model is composed of generation system reliability (GSR) service provider, power system service registry and service requester. The data pertaining to power system reliability analysis are represented in extensible markup language (XML) for exchanging the reliability data among the users and service providers. The GSR service provider describes the reliability evaluation services and publishes them to the power system service registry. The calling sequences of reliability evaluation services along with required data are configured as SOAP (Simple Object Access Protocol) messages and the proposed SOA model communicates between the service provider and the service requester with formally defined messages. The proposed model for generating system reliability analysis is highly distributed and has inherent features such as scalability and flexibility and provides a loosely coupled environment for power system reliability analysis.

As the primary heat source in the district heating systems (DHSs), combined heat and power (CHP) units are playing an increasingly significant role in electricity generation. Considering that, this paper innovatively proposes an integral generation expansion planning (GEP) framework, which enables competition to occur among conventional power plants (CPPs) of the GENCOs and CHP units of the DHSCOs. The proposed framework is based on decentralized decision-making which involves an iterative process for simulating the interactions of ISO, GENCOs, and DHSCOs. The combined heat and power dispatch model is reconstructed to determine the LMPs to offer incentives for market participants' investments. The fuzzy load duration curve (FLDC) method is proposed to model the electricity load that would influence the LMPs. In each FLDC state, uncertain load is represented by a fuzzy number. Investment decision-making models of the GENCOs and DHSCOs are formulated as a mixed integer linear programming with fuzzy objectives (MILPFO). A technique is proposed to solve the MILPOF models with the consideration of the risk appetite of the market participants. The examples illustrate the benefits of integrated planning of electric power system and DHSs.

Integration of renewable energy sources, such as wind power and solar power, into the generation system can enhance country's energy security. These alternative energy help diversify sources of primary energy used to produce electricity. However, the biggest disadvantage of using these types of renewable energy power plants is that it might reduce power system reliability because these intermittent renewable energy sources have low dependable capacity. This paper aims to evaluate the dependable capacity of wind power and solar power generation systems. It considers uncertainties due to intermittent wind speed, solar irradiance, ambient temperature, and unavailability of their corresponding generators. Additionally, load uncertainty is also taken into account. The dependable capacity of the wind power and solar power generation systems are determined from the principle of generation system reliability evaluation. The reliability index such as Loss of Load Probability (LOLP) will be used as a key indicator to define the dependable capacity.

Distributed real-time computing system JStrom significantly improves performance on real-time data computing. However, JStorm may lead to a single point of failure, and upgrading JStorm system may cause instability of system. To efficiently solve these problems, we propose a task detection model based on the heartbeat detection and a two-level cluster load balancing model separately. We discover the running state of task through heartbeat detection algorithm, and take action accordingly to avoid single point of failure. The two-level cluster load balancing model divides large cluster into sub cluster, which is isolated and upgraded one by one. Our experimental results suggest that our model can efficiently solve the underlying problems of JStorm system, significantly improve the stability of the system, reduce the probability of single point of failure and the latency of cluster process, and keep system stability during the upgrade process.

Chapter 256 - Basic Design of Electric Power Generating System with Wind Energy Generation System for a Large Ship

Probabilistic techniques are widely used in power system reliability evaluation. The average or mean values of a wide range of indices are used to assess the reliability of generation, transmission and distribution systems. These mean values are extremely valuable and are the primary indices in generation adequacy studies of power systems containing both conventional generating units and unconventional energy sources such as wind and solar energy. Additional information can, however, be created, which can prove useful in a wide range of systems and applications. The probability distributions associated with the reliability indices can be used as supplemental measures and provide valuable information for system planners and operators. This paper presents the results of a series of studies on reliability index distributions for small isolated power systems using wind energy and storage facilities. Reliability index distributions associated with generating capacity adequacy parameters such as the loss of load expectation (LOLE), expected outage frequency (EOF), expected energy supplied by the battery (EESBB) and battery discharging frequency (BDF) etc. are presented and examined.

Optimal Sizing, Scheduling and Building Structure Strategies for a Risk-averse Isolated Hybrid Energy System in Kish Island

Electromagnetic transients of a micro-turbine based distributed generation system

Process reliability modeling is of great significance to guarantee the reliability of the manufacturing process. This paper will describe how to establish the relationship between reliability index of process system and input parameters of each working procedure by studying the key characteristics of manufacturing process, which pays more attention to the process instead of product. Firstly, the key process parameters in process will be determined, whose levels can be designated appropriately according to the requirements of process reliability index. Secondly, reliability modeling method will be employed to catch the significant factors affected the reliability of process, and the relationship between output parameters of product, input value of process characteristics and reliability index were analyzed based on key characteristics. Finally, this methodology is applied into manufacturing process reliability modeling of a certain type of product, and interrelated input parameters are selected to improve reliability index of the product.

With the development of more electric aircraft (MEA), higher demands for electrical energy are put forward in generation systems. Compared to constant frequency AC (CFAC) generation systems, the constant speed drive (CSD) is eliminated and integrated starter/generator (SG) can be realized in variable frequency AC (VFAC) generation systems. In this paper, an overview of VFAC generators for safety-critical aircraft applications is presented, with a particular focus on the key features and requirements of candidate generators and the starting control strategies. Wound rotor synchronous machines (WRSMs) are typical generators used in VFAC generation systems so far. Meanwhile, hybrid excitation synchronous machines (HESMs) and cage-type induction machines are promising candidates for VFAC generation systems. The generation operation of WRSM is relatively mature, however, the SG technology of WRSM is still full of challenges. As one of the most important issues, the starting excitation methods of WRSM are summarized. An HESM-based VFAC SG system is proposed and developed in this paper. The experimental results show that the starting mode, transition mode and generating mode of the VFAC SG system are realized. The continuous progress of VFAC generation system makes great contributions to the realization of MEA.

With the deployment of advanced metering infrastructure (AMI), an avalanche of new energy-use information became available. Better understanding of the actual power consumption patterns of customers is critical for improving load forecasting and efficient deployment of smart grid technologies to enhance operation, energy management, and planning of electric power systems. Unlike traditional aggregated system-level load forecasting, the AMI data introduces a fresh perspective to the way load forecasting is performed, ranging from very short-term load forecasting to long-term load forecasting at the system level, regional level, feeder level, or even down to the consumer level. This paper addresses the efforts involved in improving the system level intraday load forecasting by applying clustering to identify groups of customers with similar load consumption patterns from smart meters prior to performing load forecasting.

This paper describes a cooperative expert system for managing the transmission expansion planning process, taking into account the selection of feasible transmission routes, as well as the definition of the expansion plan itself. The use of an expert system is proposed to create a planning environment, which can not only emulate the human expert reasoning, but also represent appropriately all heuristic knowledge related to this problem. The main point of this system is the fact that it is able to define feasible alternatives for the expansion of the electrical transmission system. Afterwards, the expert system executes a network flows program, which determines the minimum cost expansion plan. The developed prototype is tested with a realistic system of 500 busbars.

Dynamic simulation is one of the most important tools for the operation and planning of electric power systems. Accuracy of the dynamic simulation results are directly determined by the accuracy of the equipment model, especially the models of synchronous generators. This paper proposes a time-series-based synchronous generator parameter estimation technique using phasor measurement unit (PMU) data. The generator electromechanical dynamics related parameters are estimated which include generator inertia constant, speed regulation constant, and time constant of the turbine-governor, etc. The classical generator model and swing equation are transformed into a time series model whose parameters can be estimated in an indirect way using linear system parameter identification technology. Once the parameters for the time series model are calculated, the generator parameters can be recovered from the time series model. Simulation results demonstrate the effectiveness of the proposed methodology.