Maximizing performance of a grid-connected photovoltaic (PV)-fuel cell hybrid system by use of a two-loop controller is discussed. One loop is a neural network controller for maximum power point tracking, which extracts maximum available solar power from PV arrays under varying conditions of insolation, temperature, and system load. A real/reactive power controller (RRPC) is the other loop. The RRPC achieves the system's requirements for real and reactive powers by controlling incoming fuel to fuel cell stacks as well as switching control signals to a power conditioning subsystem. Results of time-domain simulations prove not only the effectiveness of the proposed computer models of the two-loop controller but also its applicability for use in stability analysis of the hybrid power plant.

Two-loop controller for maximizing performance of a grid-connected photovoltaic-fuel cell hybrid power plant

A method of determining the dynamic operating cost benefits of energy storage systems for utility applications is presented The production costing program DYNASTORE is used to analyze economic benefits for "utility B," an isolated island utility, using heuristic unit commitment algorithms The unit commitment is done using chronologic load data and a detailed model of the utility characteristics Several unit commitment scenarios are run for utility B, and the results are presented Comparisons between various battery energy storage system (BESS) applications, as well as cases with and without battery storage, are shown Results show that for utility B, a BESS of 300 MW size used for spinning reserve provides the greatest economic benefit

/pdf/assessment-of-utility-side-cost-savings-from-battery-energy-4any8i674s.pdf

Assessment of utility side cost savings from battery energy storage

This paper investigates the value of storage devices in congestion constrained distribution networks. Subject of the investigations is a load, which cannot be supplied with the desired security at all times during the day. It is analyzed what the requirements would be if a storage device would be installed at the load bus instead of network reinforcement. To compare these two possible solutions, the implications on the load flow, including loss reduction and the possibility of local voltage control, are investigated. Furthermore the availability of a system with three lines is used to determine failure and repair rate requirements for a storage device. Finally some general economical considerations are outlined.

Value of storage devices in congestion constrained distribution networks

This paper presents the study on the integration of battery energy storage system (BESS) to STATCOM for smoothing out the intermittent output power of a wind farm Lead-acid battery type is considered as the energy storage system for availability and comparably simpler management system Reviewed several modeling approaches indicating their advantages and drawbacks; particularly, appropriate for high power applicationspsila time-frames, current-based third order model is developed The experimental tests are conducted to identify the parameters and consequently, to construct the battery model The performance of the proposed system is analyzed by introducing the state-of-charge (SOC) controller implemented for this type of battery integrated to a proposed 10 MVA STATCOM for a 50 MW wind farm

Improved wind farm’s power availability by battery energy storage systems: modeling and control

Mobile energy resources (MERs) have been shown to boost DS resilience effectively in recent years. In this paper, we propose a novel idea, the separable mobile energy storage system (SMESS), as an attempt to further extend the flexibility of MER applications. &#x201C;Separable&#x201D; denotes that the carrier and the energy storage modules are treated as independent parts, which allows the carrier to carry multiple modules and scatter them independently throughout the DS. The constraints for scheduling SMESSs involving carriers and modules are derived based upon the interactive behavior among them and the DS. In addition, the fuel delivery issue of feeding mobile emergency generators (MEGs), which was usually bypassed in previous studies involving the scheduling of MEGs, is also considered and modeled. SMESSs, MEGs, and fuel tankers (FTs) are then jointly routed and scheduled, along with the dynamic DS reconfiguration, for DS service restoration by integrating them in a mixed-integer linear programming (MILP) model. Finally, the test is conducted on the modified IEEE test systems, and results verify the effectiveness of the model in boosting DS resilience. 

/pdf/scheduling-of-separable-mobile-energy-storage-systems-with-qlgllb4h.pdf

Scheduling of Separable Mobile Energy Storage Systems With Mobile Generators and Fuel Tankers to Boost Distribution System Resilience

A prototype 250 kVA modular battery energy storage system was developed and tested for utility peak-shaving applications-in a cooperative Department of Energy, industry, and utility project. The system consists of battery- and converter-integrated modules with AC terminals. Data on the system's energy capacity, power quality, power factor, auxiliary power, thermal regulation, speed of response, and islanding and other protective measures are presented. A simple method of identifying the presence of a defective battery was revealed during the test period. >

G. Corey

Papers

Government, industry, and utility development and evaluation of a modular utility battery energy storage system