Battery Based Energy Storage System Research Articles

Effect of Tariff Policy and Battery Degradation on Optimal Energy Storage

In the context of an increasing participation of renewable energy in the electricity market, demand response is a strategy promoted by electricity companies to balance the non-programmable supply of electricity with its usage. Through the use of differential electricity prices, a switch in energy consumption patterns is stimulated. In recent years, energy self-storage in batteries has been proposed as a way to take advantage of differential prices without a major disruption in daily routines. Although a promising solution, charge and discharge cycles also degrade batteries, thus expected savings in the energy bill may actually be non-existent if these savings are counterbalanced by the capacity lost by the battery. In this work a convex optimization problem that finds the operating schedule for a battery and includes the effects of current-induced degradation is presented. The goal is to have a tool that facilitates for a consumer the evaluation of the convenience of installing a battery-based energy storage system under different but given assumptions of electricity and battery prices. The problem is solved assuming operation of a commercial Li-ion under two very different yet representative electricity pricing policies.

Optimal sizing of PV and battery-based energy storage in an off-grid nanogrid supplying batteries to a battery swapping station

Nanogrids are expected to play a significant role in managing the ever-increasing distributed renewable energy sources. If an off-grid nanogrid can supply fully-charged batteries to a battery swapping station (BSS) serving regional electric vehicles (EVs), it will help establish a structure for implementing renewable-energy-to-vehicle systems. A capacity planning problem is formulated to determine the optimal sizing of photovoltaic (PV) generation and battery-based energy storage system (BESS) in such a nanogrid. The problem is formulated based on the mixed-integer linear programming (MILP) and then solved by a robust optimization approach. Flexible uncertainty sets are employed to adjust the conservativeness of the robust optimization, and Monte Carlo simulations are carried out to compare the performance of the solutions. Case studies demonstrate the merits of the proposed applications and verify our approach.

A Practical Lithium-Ion Battery Model for State of Energy and Voltage Responses Prediction Incorporating Temperature and Ageing Effects

The state of energy (SOE) is a key indicator for the energy optimization and management of lithium-ion (Li-ion) battery-based energy storage systems in smart grid applications. To improve the SOE estimation accuracy, a Li-ion battery model is presented in this study against dynamic loads and battery ageing effects. First, an electrical battery model is combined with an analytical model in order to take advantages of both models for accurate prediction of battery terminal voltage characteristics, SOE, and remnant runtime. Second, a novel method to separate the fast and slow dynamics of the electrical battery model is developed, and its superior performance is presented. Third, the effects of the battery initial SOC, load current rate and direction, operating temperature, and ageing level are systematically scrutinized and involved in the proposed model for robust SOE and terminal voltage prediction. Commercial Li-ion batteries are then tested under dynamic loads and at an arbitrary battery ageing level to validate the effectiveness and robustness of the proposed model. The laboratory-scale experimental test results show superb accuracy and reliability of the proposed battery model for estimating battery SOE and terminal voltage under dynamic loads and battery ageing conditions.

An improved dynamic performance of bidirectional SEPIC-Zeta converter based battery energy storage system using adaptive sliding mode control technique

An improved dynamic performance of DC–DC bidirectional SEPIC-Zeta converter based battery energy storage system (BESS) has been achieved using adaptive sliding mode control (SMC) technique. The micro-grid concept is gaining importance for integrating various nonconventional energy sources throughout the world. Nowadays, both DC and AC micro-grid systems are employing BESS for getting various advantages such as minimization of power fluctuations, excess or emergency power support etc. In this application, controlled charging and discharging operation of the concerned battery bank is extremely needed. In this scenario, DC to DC bidirectional converter such as combined SEPIC-Zeta converter is considered to facilitate dynamic charging and discharging operation of the concerned battery. Conventional proportional-integral-derivative (PID) controller based control strategy for the bidirectional converter can not always meet the dynamic performance requirements under charging and discharging operation cycles of the battery. Therefore, adaptive SMC action has been proposed to improve both transient and steady state behavior of the BESS. In addition to this, the proposed model can be operated satisfactorily under changed operating condition. The proposed concept is validated via various simulation studies using MATLAB-SIMULINK software. The experimental study is also performed on a prototype of the BESS to validate adaptive SMC case.

A Communication-Less Distributed Control Architecture for Islanded Microgrids With Renewable Generation and Storage

For reliable operation of an islanded microgrid, at least one of its distributed resources should assume the responsibility of forming the off-grid power system. This responsibility is usually assumed by energy storage systems based on their capability of compensating the unbalance between generation and consumption. However, the storage units lose this capability when they reach the maximum and minimum limits of charge. Under these conditions, the regulation of the power grid may be assumed by another unit with enough capability or the power balance should be adjusted coordinately. This paper proposes a coordination architecture for islanded ac microgrids, which considers the appropriate charge profiles for battery-based energy storage systems. The architecture is based on distributed decision-making mechanisms, which use only local measurements for determining the operation mode of each unit independently. The coordination relies on a bus-signaling method, which enables the distributed units to have a global perception about the operation of the microgrid, without any communication infrastructure. The proposed architecture includes cooperative operation between distributed energy storage systems for achieving the equalization of the states of charge. Experimental results in a lab-scale microgrid with network configuration validate the proposed strategy under different operational conditions.

Synchronous Boost Converter With High Efficiency at Light Load Using QSW-ZVS and SiC mosfets

A converter intended to be used for the interconnection of battery-based energy storage systems with the cells of a multilevel converter is addressed in this paper. High efficiency at light and medium loads is important in these applications and it can be achieved using soft switching techniques. Two control techniques with fixed and variable switching frequency are proposed and compared. The use of silicon carbide (SiC) mosfet s provides a higher attainable switching frequency, which is especially interesting in variable frequency control techniques, allowing the operation at high voltages and high switching frequencies, with high efficiencies over a wide power range. A synchronous boost DC/DC converter rated for 400 to 800 V and 10 kW is designed and developed with SiC mosfet s obtaining efficiencies higher than 97% from 100% to 3.5% of full load using a variable switching frequency (up to 200 kHz) control. Significant efficiency improvement is achieved at medium and light loads.

Peak reduction for commercial buildings using energy storage

Battery-based energy storage has emerged as a cost-effective solution for peak reduction due to the decrement of battery’s price. In this study, a battery-based energy storage system is developed and implemented to achieve an optimal peak reduction for commercial customers with the limited energy capacity of the energy storage. The energy storage system is formed by three bi-directional power converter rated at 5 kVA and a battery bank with capacity of 64 kWh. Three control algorithms, namely fixed-threshold, adaptive-threshold, and fuzzy-based control algorithms have been developed and implemented into the energy storage system in a campus building. The control algorithms are evaluated and compared under different load conditions. The overall experimental results show that the fuzzy-based controller is the most effective algorithm among the three controllers in peak reduction. The fuzzy-based control algorithm is capable of incorporating a priori qualitative knowledge and expertise about the load characteristic of the buildings as well as the useable energy without over-discharging the batteries.

Energy Storage: From Holywood Stunt Double to Action Hero [In My View

Discusses the growing market for advanced battery-based energy storage systems and reports on applications for their use.

A Polymer-Infused Solid-State Synthesis of a Long Cycle-Life Na3V2(PO4)3/C Composite

The cost of large-scale battery-based energy storage systems can be substantially reduced by using long cycle-life active battery materials which can be easily synthesized. This paper describes the synthesis of a sodium vanadium phosphate (Na3V2(PO4)3, NVP)/carbon composite as the sodium ion battery (NIB) cathode material by a facile solid-state method which can increase the cost competitiveness of NIBs relative to the lithium ion batteries (LIBs). The NVP synthesized as such features NVP particles tethering to a cellular carbon network formed in situ by the carbonization of a low melting polymer percolating the NVP particles. The immobilization of the NVP particles can better preserve their electrical integration within the electrode, the loss of which is conjectured to be the major cause of capacity loss. The hypothesis was validated by performance comparison with a conventional carbon-coated NVP/C composite with the same initial discharge capacity but which showed a more severe capacity fading in exten...

Definitions and reference values for battery systems in electrical power grids

Since more and more large battery based energy storage systems get integrated in electrical power grids, it is necessary to harmonize the wording of the battery world and of the power system world, in order to reach a common understanding. In this regard this article presents different battery content values and their relation to each other. Battery operations typically lead to a change of battery’s electric charge or energy content. Based on a simplified battery model the basic values necessary to describe battery operations are clarified. Then the reference values and some acceptance criteria for batteries and secondary cells are defined. Also values describing limited usable energy content caused by operational restrictions are provided. In order to be as close as possible to existing definitions and practical applications, care is taken to be conform to current standards wherever possible in this article. The given set of consistent battery definitions can be used for an agreed design of battery storage systems and provides options for battery performance criteria.

Active Control Strategy of Energy Storage System for Reducing Maximum Demand Charges under Limited Storage Capacity

AbstractCommercial and industrial customers are subject to monthly maximum demand charges, which can be as high as 30% of the total electricity bill. A battery-based energy storage system (BESS) ca...

A novel fuzzy control algorithm for reducing the peak demands using energy storage system

Commercial and industrial customers are subject to the monthly maximum demand charges which can be as high as 30% of the total electricity bills. Battery-based energy storage system (BESS) can be used to reduce the monthly maximum demand charges. A number of control strategies have been developed for the BESS to reduce the daily peak demands. A fuzzy control algorithm is developed to reduce the daily peak demands with the limited capacity of the BESS. Its performance is evaluated at two different buildings, namely building A and B. The fuzzy controller forecasts the load profile one day in advance using the historical load data. Then during the day of peak reduction, the controller will adjust the power output of BESS using the latest state of charge and operation time. The performance of the fuzzy controller is compared with other two controllers developed in the past. The experimental results show that fuzzy controller is the most effective approach for the peak reduction under the limited capacity of the BESS.

A Study on Integration of 1kW PEM Fuel Cell into a Smart Microgrid System with Programmable Scenario

Hybrid Renewable Energy System (SHET) is a smart microgrid system that has been implemented in Energy Management Laboratory – ITB. The SHET consists of photovoltaic power plant, national electricity grid, battery based energy storage system and hybrid energy controller system. This SHET is operated to supply electricity to the laboratory. In this paper, 1 KW Proton Exchange Membrane Fuel Cell (PEMFC) integrated to the microgrid system is investigated. The PEMFC fuel cell is connected to the SHET through DC coupling method as one input for the hybrid energy controller. To optimize the energy conversion of the PEMFC and also to stabilize the input voltage to the hybrid energy controller, Maximum Power Point Tracker (MPPT) is used. This MPPT also functions as DC-DC converter. In this microgrid system where the PEMFC is also incorporated, the PEMFC will only supply its generated electricity whenever the system is in island mode with additional configured specific conditions such as battery's State of Charge (SoC) is lower than 40% or electricity load of the microgrid system is more than 0.72kW. The result of study showed that the PEMFC only generated 120-160W from its potential maximum power of 1kW. This happened because the battery voltage closes to the PEMFC Open Circuit Voltage (OCV) so the MPPT cannot operate the PEMFC to its Maximum Power Point. The low electrical power is supplied to system makes the battery still on discharge when the electricity load is in high level. This means, the PEMFC and battery work simultaneously at the same time. From this research, it has been found out that other solutions may be implement to maximize the generated power from the PEMFC

Sizing Study of Second Life Li-ion Batteries for Enhancing Renewable Energy Grid Integration

Renewable power plants must comply with certain codes and requirements to be connected to the grid, being the ramp-rate compliance one of the most challenging requirements, especially for photovoltaic or wind energy generation plants. Battery-based energy storage systems represent a promising solution due to the fast dynamics of electrochemical storage systems, besides their scalability and flexibility. However, large-scale battery energy storage systems are still too expensive to be a mass market solution for the renewable energy resources integration. Thus, in order to make battery investment economically viable, the use of second life batteries is investigated in the paper. This paper proposes a method to determine the optimal sizing of a second life battery energy storage system (SLBESS). SLBESS performance is also validated and, as an ultimate step, the power exchanged with the batteries is calculated during one-year operation. The power profile obtained is further used to define the cycling patterns for laboratory testing of second life batteries and to study their ageing evolution when used for the power smoothing renewable integration application. Real photovoltaic energy generation data from a Spanish plant were used for the study.

Evaluation of technical and financial benefits of battery‐based energy storage systems in distribution networks

Prompted by technical issues that have arisen due to the widespread deployment of distributed intermittent renewable generators, rapidly rising peak demand and reductions in battery price, the use of battery-based energy storage systems in power networks is on the rise. While battery-based energy storage has the potential to deliver technical benefits, the best possible sizing, location and usage govern the financial viability. The objective of this study is twofold. Firstly, a generalised approach is proposed to model network upgrade deferral as a function of load growth rate, renewable generation penetration and peak shave fraction. This model is then used for the formulation of an optimisation problem which benefits from multi-period power flow analysis to co-optimise battery size, location, charge/discharge profile for a pre-specified number of units to be deployed in a given distribution network. The proposed approach is implemented using the generic algebraic modelling system platform and validated on an Australian medium voltage distribution network under multiple practical and potential future scenarios.

Modelling Of Wind Diesel Hybrid System for Reverse Power Management Using Bess.

This paper presents the modeling of a Wind Diesel Hybrid System (WDHS) comprising a Diesel Generator (DG), a Wind Turbine Generator (WTG), the consumer Load, a Ni–Cd Battery based Energy Storage System (BESS) and a Distributed Control System (DCS). All the models of the previously mentioned components are presented and the performance of the WDHS is tested through simulation. Simulation results with graphs for frequency and voltage of the isolated power system, active powers generated/absorbed by the different elements and the battery voltage/current/state of charge are presented for negative load and wind speed steps. The negative load step reduces the load consumed power to a level less than the WTG produced power, so that to balance active powers a negative DG power is needed (DG reverse power). As the DG speed governor cannot control system frequency in a DG reserve power situation, it is shown how the DCS orders the BESS to load artificially the system until the DG power falls in a positive power interval. The negative wind step decreases the WTG produced power, returning the power system to a situation where the needed DG power returns to positive, so that the BESS is not needed to load the system.

Design of Controls, Monitoring and a Energy Storage System for a Energy Harvesting Gymnasium Equipment

The energy harvesting development was to monitor, control and optimize the output power from the gym equipment. The designed utilized Arduino and LabVIEW based Battery Energy Storage System (BESS) that incorporated switchover capability according to the load power. The manual gears-shifting mechanism was improved with the aid of a DC geared motor and L298N controller to be automatically controlled by the user’s input via a keypad.

Adaptive Critic Design-Based Dynamic Stochastic Optimal Control Design for a Microgrid With Multiple Renewable Resources

This paper proposes a three-layer optimization and an intelligent control algorithm for a microgrid with multiple renewable resources. A dual heuristic dynamic programming-based system control layer is used to ensure the dynamic performance and voltage dynamics of the microgrid as the system operation conditions change. A local layer maximizes the capability of the photovoltaic (PV) wind power generators and battery systems, and a model predictive control-based device layer increases the tracking accuracy of the converter control. The proposed control scheme, system wide adaptive predictive supervisory control (SWAPSC) smooths the output of PV and wind generators under intermittencies, maintains bus voltage by providing dynamic reactive power support to the grid, and reduces the total system losses while minimizing degradation of battery life span. Performance comparisons are made with and without SWAPSC for an IEEE 13 node test system with a PV farm, a wind farm, and two battery-based energy storage systems.

Application of Hyper-Spherical Search algorithm for optimal energy resources dispatch in residential microgrids

This paper presents a residential hybrid thermal/electrical grid-connected home energy system (HES), including a fuel-cell with combined heat and power and a battery-based energy storage system. The minimum operation cost of this integrated energy system is achieved by proper scheduling of different energy resources, found by applying a new powerful optimization algorithm, the Hyper-Spherical Search (HSS) algorithm, to the system's scheduling problem. This is the first time that HSS is used to face the energy resource dispatch problem. The HSS has been only tested in mathematical problems in the previous study. The optimization procedure generates an efficient look-up table in which the powers generated by different energy resources are determined for all time intervals. The effect of different electricity tariffs for purchasing electricity from the main grid on the operation costs of the system is investigated. Moreover, a battery is properly dispatched in the energy system to decrease the operation costs. A real load demand is used in the simulation. The results of HSS are compared with the harmony search algorithm and the colonial competitive algorithm to show the power and effectiveness of HSS to find the optimal dispatch strategy of energy resources for the first time. This is the first time that HSS is compared with CCA. The results of this paper are expected to contribute to home energy systems and real projects.

Irrigation System Using Photovoltaics and Lithium Ion Batteries for Energy Storage

Typically, energy consuming systems are run off the traditional grid. However, there are remote areas of the United States that don’t have access to the traditional grid and in those places, there is a need for photovoltaic generation to supply those electricity needs [1].The use of photovoltaics along with lithium batteries for storing excess energy has increased due to the need for renewable energy as a viable source of electricity. Such energy storage systems (ESS) are useful for complex irrigation systems that assist in the cultivating of the United States food supply [2]. Without the ESS systems, maintaining a stable economy may be difficult in extreme cases. The object of this research will be to construct a virtual photovoltaic generation system that is capable of powering an irrigation system, and it will also be used in tandem with a lithium-ion battery storage system. The focus of this irrigation system will be to water a tomato farm in the Florida climate. The work will be performed in a virtual environment using a modular approach to a system-level design that simulates the behavior of the photovoltaic system and the degradation of the lithium-ion battery pack. Ultimately, these results suggest the necessary components for a real photovoltaic and battery operated system require the optimally sized photovoltaic panel and inverter connected to a watering pump. The PV panels convert solar energy to electrical energy with DC current and the inverter converts DC current to AC current required to run the pump. In addition, Additional information from hygrometer readings and weather profile also would be needed with a optimizing algorithm to ensure efficient irrigation operation. Acknowledgment This work was supported by the FREEDM ERC program of the National Science Foundation under award number EEC-08212121. References Louy Qoaider, Dieter Steinbrecht, Photovoltaic systems: A cost competitive option to supply energy to off-grid agricultural communities in arid regions, Applied Energy, Volume 87, Issue 2, February 2010, Pages 427-435, ISSN 0306-2619 M. Arifujjaman, A comprehensive power loss, efficiency, reliability and cost calculation of a 1 MW/500 kWh battery based energy storage system for frequency regulation application, Figure 1