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Processes
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Energy Storage System: Integration, Power Quality, and Operation
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Energy Storage System: Integration, Power Quality, and Operation

A special issue of Processes (ISSN 2227-9717). This special issue belongs to the section "Energy Systems".

Deadline for manuscript submissions: closed (20 May 2020) | Viewed by 43085

Special Issue Editor

Prof. Dr. Dongjun Won

E-Mail Website
Guest Editor
Department of Electrical Engineering, College of Engineering, Inha University, Incheon 22212, Korea
Interests: energy storage system; microgrid; EV charging infra; peer to peer energy trading

Special Issue Information

Dear Colleagues,

The energy storage system (ESS) is becoming an essential component of modern power systems. It can provide various functions such as frequency regulation, mitigation of renewable energy fluctuations, peak shaving, peak shifting, UPS backup, etc. There are various kinds of energy storage systems, e.g., Li-ion batteries, flow batteries, NaS batteries, flywheels, compressed air, etc. These kinds of energy storage systems have their own purposes and have become competitive nowadays. The ESS technology is composed of various technologies regarding materials, devices, controls, and system integration. BMS, PMS, inverter, and other controllers cooperate for the stable and efficient operation of ESS. Recent researches on ESS have been focusing on their actual applications, such as Microgrids, Virtual Power Plants (VPP), Peer-to-Peer (P2P) energy trading, etc. In addition, issues of cyber security and protection from fire are also important in the ESS industry.

This Special Issue on “Energy Storage System: Integration, Power Quality, and Operation” aims to promote ESS research on ESS integration technologies, enhancing the quality of power systems with ESS by using various operation algorithms. It also welcomes high-quality studies on various applications of EES, such as Microgrids, VPP, P2P, V2G.

Prof. Dongjun Won
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Processes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Optimal operation and control
  • Power quality enhancement
  • Integration and demonstration of ESS
  • Multi-functional ESS
  • Electric vehicle charging as ESS
  • Microgrid operation
  • Virtual power plant operation
  • Peer-to-peer energy trading

Published Papers (14 papers)

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Research

17 pages, 4660 KiB  
Article
Optimal Scheduling of Island Microgrid with Seawater-Pumped Storage Station and Renewable Energy
by Ning Liang, Pengcheng Li, Zhijian Liu, Qi Song and Linlin Luo
Processes 2020, 8(6), 737; https://doi.org/10.3390/pr8060737 - 24 Jun 2020
Cited by 7 | Viewed by 2355
Abstract
The rapid development of renewable energy, represented by wind and photovoltaic, provides a new solution for island power supplies. However, due to the intermittent and random nature of renewable energy, a microgrid needs energy-storage components to stabilize its power supply when coupled with [...] Read more.
The rapid development of renewable energy, represented by wind and photovoltaic, provides a new solution for island power supplies. However, due to the intermittent and random nature of renewable energy, a microgrid needs energy-storage components to stabilize its power supply when coupled with them. The emergence of seawater-pumped storage stations provides a new method to offset the shortage of island power supply. In this study, an optimal scheduling of island microgrid is proposed, which uses seawater-pumped storage station as the energy storage equipment to cooperate with wind, photovoltaic and diesel generator. First, a mathematic formulation of seawater-pumped storage station with renewable energy is presented. Then, to reach the goal of economic dispatch, an optimal scheduling model of island microgrid is established with the consideration of both respective operation constraints and island load requirements. Finally, the effectiveness of the proposed model is verified by an island microgrid over two typical seasons. The simulation results show that the proposed framework not only increases the usage of renewable energy, but also improves the operational reliability and economy of island microgrids. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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15 pages, 8095 KiB  
Article
Adaptive Control Strategy of Energy Storage System Participating in Primary Frequency Regulation
by Chaoxiong Fang, Yuchen Tang, Rong Ye, Zhangsui Lin, Zhenshan Zhu, Buying Wen and Chengtao Ye
Processes 2020, 8(6), 687; https://doi.org/10.3390/pr8060687 - 12 Jun 2020
Cited by 8 | Viewed by 2529
Abstract
In order to solve the capacity shortage problem in power system frequency regulation caused by large-scale integration of renewable energy, the battery energy storage-assisted frequency regulation is introduced. In this paper, an adaptive control strategy for primary frequency regulation of the energy storage [...] Read more.
In order to solve the capacity shortage problem in power system frequency regulation caused by large-scale integration of renewable energy, the battery energy storage-assisted frequency regulation is introduced. In this paper, an adaptive control strategy for primary frequency regulation of the energy storage system (ESS) was proposed. The control strategy combined virtual droop control, virtual inertial control, and virtual negative inertial control. The virtual inertial control was used to reduce the frequency change rate, and the virtual droop control was used to reduce the steady-state frequency deviation. The virtual droop control and the virtual inertia control were adopted in the frequency deterioration stage to slow down the frequency drop. While in the frequency recovery stage, the virtual negative inertia control worked together with the virtual droop control to accelerate the frequency recovery. Besides, the coefficients of the control methods were related to the state of charge (SOC) of ESS to avoid over-charging and over-discharging of the battery. Finally, a simulation model was built in MATLAB/SIMULINK, and case studies were conducted to verify the proposed control strategy. Results showed that the proposed method could meet the demand for frequency regulation and was beneficial to the cycle life of ESS. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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16 pages, 5112 KiB  
Article
Two-Layer Optimization Model for the Siting and Sizing of Energy Storage Systems in Distribution Networks
by Tao Sun, Linjun Zeng, Feng Zheng, Ping Zhang, Xinyao Xiang and Yiqiang Chen
Processes 2020, 8(5), 559; https://doi.org/10.3390/pr8050559 - 09 May 2020
Cited by 3 | Viewed by 1948
Abstract
One of the most important issues that must be taken into consideration during the planning of energy storage systems (ESSs) is improving distribution network economy, reliability, and stability. This paper presents a two-layer optimization model to determine the optimal siting and sizing of [...] Read more.
One of the most important issues that must be taken into consideration during the planning of energy storage systems (ESSs) is improving distribution network economy, reliability, and stability. This paper presents a two-layer optimization model to determine the optimal siting and sizing of ESSs in the distribution network and their best compromise between the real power loss, voltage stability margin, and the application cost of ESSs. Thereinto, an improved bat algorithm based on non-dominated sorting (NSIBA), as an outer layer optimization model, is employed to obtain the Pareto optimal solution set to offer a group of feasible plans for an internal optimization model. According to these feasible plans, the method of fuzzy entropy weight of vague set, as an internal optimization model, is applied to obtain the synthetic priority of Pareto solutions for planning the optimal siting and sizing of ESSs. By this means, the adopted fuzzy entropy weight method is used to obtain the objective function’s weights and vague set method to choose the solution of planning ESSs’ optimal siting and sizing. The proposed method is tested on a real 26-bus distribution system, and the results prove that the proposed method exhibits higher capability and efficiency in finding optimum solutions. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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16 pages, 3735 KiB  
Article
An Autonomous Power-Frequency Control Strategy Based on Load Virtual Synchronous Generator
by Jiangbei Han, Zhijian Liu, Ning Liang, Qi Song and Pengcheng Li
Processes 2020, 8(4), 433; https://doi.org/10.3390/pr8040433 - 07 Apr 2020
Cited by 4 | Viewed by 2417
Abstract
With the increasing penetration of the hybrid AC/DC microgrid in power systems, an inertia decrease of the microgrid is caused. Many scholars have put forward the concept of a virtual synchronous generator, which enables the converters of the microgrid to possess the characteristics [...] Read more.
With the increasing penetration of the hybrid AC/DC microgrid in power systems, an inertia decrease of the microgrid is caused. Many scholars have put forward the concept of a virtual synchronous generator, which enables the converters of the microgrid to possess the characteristics of a synchronous generator, thus providing inertia support for the microgrid. Nevertheless, the problems of active power oscillation and unbalance would be serious when multiple virtual synchronous generators (VSGs) operate in the microgrid. To conquer these problems, a VSG-based autonomous power-frequency control strategy is proposed, which not only independently allocates the power grid capacity according to the load capacity, but also effectively suppresses the active power oscillation. In addition, by establishing a dynamic small-signal model of the microgrid, the dynamic stability of the proposed control strategy in the microgrid is verified, and further reveals the leading role of the VSG and filter in the dynamic stability of microgrids. Finally, the feasibility and effectiveness of the proposed control strategy are validated by the simulation results. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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17 pages, 2512 KiB  
Article
Load Frequency Control of Pumped Storage Power Station Based on LADRC
by Kezhen Liu, Jing He, Zhao Luo, Hua Shan, Chenglong Li, Rui Mei, Quanchun Yan, Xiaojian Wang and Li Wei
Processes 2020, 8(4), 380; https://doi.org/10.3390/pr8040380 - 25 Mar 2020
Cited by 13 | Viewed by 3214
Abstract
The pumped storage power station has the characteristics of frequency-phase modulation, energy saving, and economy, and has great development prospects and application value. In order to cope with the large-scale integration and intermittency of renewable energy and improve the ability of pumped storage [...] Read more.
The pumped storage power station has the characteristics of frequency-phase modulation, energy saving, and economy, and has great development prospects and application value. In order to cope with the large-scale integration and intermittency of renewable energy and improve the ability of pumped storage units to participate in power grid frequency modulation, this paper proposed a load frequency control (LFC) strategy for pumped storage units based on linear active disturbance rejection technology. Firstly, based on the operating characteristics of the pumped storage power station, the LFC model of the two-area reheat steam turbine under nonlinear conditions such as governor dead zone and generation rate constrains was established. Secondly, a second-order linear active disturbance rejection control (LADRC) was designed. The feasibility and control performance of the proposed LFC system were quantitatively analyzed through simulation. The results show that the LADRC has better control effect and stronger robustness than fractional-order proportion integration differentiation (FOPID) and traditional proportion integration differentiation (PID) controller. Finally, the pumped storage power station was added, and it was found that it has better correction performance under both generating and pumping operations, which greatly improved the dynamic response of secondary frequency modulation. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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15 pages, 3832 KiB  
Article
A Cooperative Control Scheme for AC/DC Hybrid Autonomous Microgrids
by Wanxing Sheng, Yinqiu Hong, Ming Wu and Yu Ji
Processes 2020, 8(3), 311; https://doi.org/10.3390/pr8030311 - 07 Mar 2020
Cited by 5 | Viewed by 2721
Abstract
The AC/DC hybrid microgrid (MG) has been widely promoted due to its high flexibility. The capability to operate in islanding mode is an appealing advantage of the MG, and also sets higher requirements for its control system. A droop control strategy is proposed [...] Read more.
The AC/DC hybrid microgrid (MG) has been widely promoted due to its high flexibility. The capability to operate in islanding mode is an appealing advantage of the MG, and also sets higher requirements for its control system. A droop control strategy is proposed on account of its distinguishing feature of automatic power sharing between distributed generations (DGs), but it introduces some drawbacks. Therefore, distributed cooperative secondary control is introduced as an improvement. In order to optimize the active power sharing in AC/DC hybrid microgrids, a number of cooperative control strategies have been proposed. However, most studies of AC/DC hybrid microgrids have mainly focused on the control of the bidirectional converter, ignoring the effects of secondary control within subnets, which may make a difference to the droop characteristic. This paper extends the cooperative control to AC/DC hybrid microgrids based on normalizing and synthesizing the droop equations, and proposes a global cooperative control scheme for AC/DC autonomous hybrid microgrids, realizing voltage restoration within AC and DC subnets as well as accurate global power sharing. Ultimately, the simulation results demonstrate that the proposed control scheme has a favorable performance in the test AC/DC hybrid system. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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14 pages, 10091 KiB  
Article
A Self-Adaptive Damping Control Strategy of Virtual Synchronous Generator to Improve Frequency Stability
by Tianyang Li, Buying Wen and Huaiyuan Wang
Processes 2020, 8(3), 291; https://doi.org/10.3390/pr8030291 - 04 Mar 2020
Cited by 5 | Viewed by 3340
Abstract
In a microgrid, grid-connected inverters, as the interface between the distributed power supply and grid, cannot provide inertia support for the system. The control strategy of virtual synchronous generator (VSG) based on grid-connected inverters can enhance the stability of system frequency. In order [...] Read more.
In a microgrid, grid-connected inverters, as the interface between the distributed power supply and grid, cannot provide inertia support for the system. The control strategy of virtual synchronous generator (VSG) based on grid-connected inverters can enhance the stability of system frequency. In order to make the frequency response that has a smaller overshoot and a shorter settling time, a self-adaptive damping control strategy based on the relationship between the damping and the maximum frequency deviation for microgrid VSG is presented. The small-signal mathematical model of VSG is established, and the range of the damping coefficient is determined. Finally, simulation experiments are carried out with MATLAB/Simulink, and the effectiveness of the proposed control strategy is verified by comparing it with various damping control methods. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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13 pages, 3454 KiB  
Article
Research on Frequency Control of Islanded Microgrid with Multiple Distributed Power Sources
by Yirong Liu, Xiaoli Wang and Shilin Wang
Processes 2020, 8(2), 193; https://doi.org/10.3390/pr8020193 - 05 Feb 2020
Cited by 9 | Viewed by 3854
Abstract
At present, some achievements have been made in the research on the energy management of microgrid operation. However, the research is mainly on the operation of grid-connected microgrid, while the research on the energy management of islanded microgrid is still relatively few. Frequency [...] Read more.
At present, some achievements have been made in the research on the energy management of microgrid operation. However, the research is mainly on the operation of grid-connected microgrid, while the research on the energy management of islanded microgrid is still relatively few. Frequency is one of the characteristics that affects the reliability and power quality of the microgrid. The essence of controlling frequency stability is to maintain source-load balance and redistribution of active power. Therefore, this paper proposes a frequency control strategy based on dynamically cutting machine to reduce load by analyzing the use priority of different distributed power supply and the division of load importance degree, and combining the influence degree of different frequency variation range on microgrid. To coordinate and control distributed power supply, energy storage device, and load in different frequency change areas, this paper proposes different control strategies. The seed strategies of the control strategy are discussed one by one. Experimental results show that the frequency control strategy can significantly improve the frequency stability of the power supply system and reduce the operating cost of islanded microgrid. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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22 pages, 10728 KiB  
Article
Design and Implementation of a Hybrid Real-Time State of Charge Estimation Scheme for Battery Energy Storage Systems
by Chao-Tsung Ma
Processes 2020, 8(1), 2; https://doi.org/10.3390/pr8010002 - 18 Dec 2019
Cited by 2 | Viewed by 3187
Abstract
In order to maximize the operating flexibility and optimize the system performance of a battery energy storage system (BESS), developing a reliable real-time estimation method for the state of charge (SOC) of a BESS is one of the crucial tasks. In practice, the [...] Read more.
In order to maximize the operating flexibility and optimize the system performance of a battery energy storage system (BESS), developing a reliable real-time estimation method for the state of charge (SOC) of a BESS is one of the crucial tasks. In practice, the accuracy of real-time SOC detection can be interfered with by various factors, such as battery’s intrinsic nonlinearities, working current, temperature, and aging level, etc. Considering the feasibility in practical applications, this paper proposes a hybrid real-time SOC estimation scheme for BESSs based on an adaptive network-based fuzzy inference system (ANFIS) and Coulomb counting method, where a commercially available lead-acid battery-based BESS is used as the research target. The ANFIS allows effective learning of the nonlinear characteristics in charging and discharging processes of a battery. In addition, the Coulomb counting method with an efficiency adjusting mechanism is simultaneously used in the proposed scheme to provide a reference SOC for checking the system reliability. The proposed estimating scheme was first simulated in a Matlab software environment and then implemented with an experimental hardware setup, where an industrial-grade digital control system using DS1104 as the control kernel and dSPACE Real-Time Interface (RTI) interface were used. Results from both simulation and experimental tests verify the feasibility and effectiveness of the proposed hybrid SOC estimation algorithm. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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19 pages, 6063 KiB  
Article
Modeling and Analysis of Maximum Power Tracking of a 600 kW Hydraulic Energy Storage Wind Turbine Test Rig
by Liejiang Wei, Peng Zhan, Zengguang Liu, Yanhua Tao and Daling Yue
Processes 2019, 7(10), 706; https://doi.org/10.3390/pr7100706 - 05 Oct 2019
Cited by 8 | Viewed by 2701
Abstract
An innovative wind turbine with a particular hydraulic transmission and energy storage system is proposed in this paper. The purpose of applying the hydraulic transmission is to remove the gearbox and power converter of traditional wind turbine and cooperate on wind resource storing [...] Read more.
An innovative wind turbine with a particular hydraulic transmission and energy storage system is proposed in this paper. The purpose of applying the hydraulic transmission is to remove the gearbox and power converter of traditional wind turbine and cooperate on wind resource storing with the energy storage system. To overcome the volatility and intermittence shortcomings of wind and improve the output power quality, hydraulic accumulators are used as the energy storage device for wind energy regulation. The original gearbox and generator in the nacelle of a Micon 600 wind turbine were removed and replaced with a hydraulic pump to make a test rig for the investigation into maximum power point tracking (MPPT) of this hydraulic wind turbine concept. The mathematical model of the entire test system is established according to the four function modules. The MPPT control strategy based on the tip speed ratio (TSR) is adopted and a control system containing three closed-loop controls is designed to achieve maximum wind power extracting and produce constant frequency power generation. Ultimately, the dynamic response of rotor speed control is revealed under step change of wind speed and the maximum power tracking performance of the 600 kW hydraulic energy storage wind turbine test bench is simulated and analysed by subjecting to turbulent speed condition. The simulation results demonstrate that the rotor of the wind turbine can run at the expected optimal speed depending on wind speed, and the wind power utilization coefficient of the unit is stabilized at about the maximum value. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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14 pages, 2279 KiB  
Article
Optimal Allocation of Energy Storage System Considering Price-Based Demand Response and Dynamic Characteristics of VRB in Wind-PV-ES Hybrid Microgrid
by Qingwu Gong, Jintao Fang, Hui Qiao, Dong Liu, Si Tan, Haojie Zhang and Haitao He
Processes 2019, 7(8), 483; https://doi.org/10.3390/pr7080483 - 01 Aug 2019
Cited by 17 | Viewed by 2884
Abstract
Studying the influence of the demand response and dynamic characteristics of the battery energy storage on the configuration and optimal operation of battery energy storage system (BESS) in the Wind-Photovoltaic (PV)-Energy Storage (ES) hybrid microgrid. A demand response model that is based on [...] Read more.
Studying the influence of the demand response and dynamic characteristics of the battery energy storage on the configuration and optimal operation of battery energy storage system (BESS) in the Wind-Photovoltaic (PV)-Energy Storage (ES) hybrid microgrid. A demand response model that is based on electricity price elasticity is established based on the time-of-use price. Take the capital-operating cost and direct economic benefit of the BESS and the loss of abandoned photovoltaic and wind power as the optimization objective, an optimal configuration method that considers the dynamic characteristics of the BESS and the maximum absorption of photovoltaic and wind power is proposed while using particle swarm optimization to solve. The results show that the configuration results considering the demand side response of the microgrid BESS can obtain better economy and reduce the storage capacity requirement, and the result shows that the efficiency of BESS relates to the load of the system, the distributed generation (DG) characteristics, and the dynamic characteristics of BESS. Meanwhile, the capacity and power of the energy storage configuration increase as the DG permeability increases due to the reverse load characteristic of the wind power. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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15 pages, 1764 KiB  
Article
Control Strategy for Inverter Air Conditioners under Demand Response
by Yanbo Che, Jianxiong Yang, Yuancheng Zhao and Siyuan Xue
Processes 2019, 7(7), 407; https://doi.org/10.3390/pr7070407 - 01 Jul 2019
Cited by 5 | Viewed by 3415
Abstract
Air conditioning loads are important resources for demand response. With the help of thermal energy storage capacity, they can reduce peak load, improve the reliability of power grid operations, and enhance the emergency capacity of a power grid, without affecting the comfort of [...] Read more.
Air conditioning loads are important resources for demand response. With the help of thermal energy storage capacity, they can reduce peak load, improve the reliability of power grid operations, and enhance the emergency capacity of a power grid, without affecting the comfort of the users. In this paper, a virtual energy storage model for inverter air conditioning loads, which reflects their operating characteristics and is more conducive to practical application, is established. Two parts are involved in the virtual energy storage model: An electrical parameter part, based on the operating characteristics, and a thermal parameter part, based on the equivalent thermal parameter model. The control function and restrictive conditions of the virtual energy storage are analyzed and a control strategy, based on virtual state-of-charge ranking, is proposed. The strategy controls the inverter air conditioners through re-assigning indoor temperature set-points within the pre-agreed protocol interval and gives priority those with a higher virtual state of charge. As a result, electric power consumption is reduced while the temperature remains unchanged, so that a shortage in the power system can be compensated for as much as possible, while the comfort of users is guaranteed. Simulation and example analyses show that the strategy is effective in controlling air conditioning loads. Additionally, the influences of load reduction target magnitude and communication time-step on the performance of the control strategy are analyzed. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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16 pages, 17935 KiB  
Article
Analysis of Dynamic Characteristics of a 600 kW Storage Type Wind Turbine with Hybrid Hydraulic Transmission
by Zengguang Liu, Yanhua Tao, Liejiang Wei, Peng Zhan and Daling Yue
Processes 2019, 7(7), 397; https://doi.org/10.3390/pr7070397 - 26 Jun 2019
Cited by 9 | Viewed by 3420
Abstract
In order to improve the efficiency and convenience of wind energy storage and solve the reproducibility of the hydraulic wind turbine, we present a storage type wind turbine with an innovative hybrid hydraulic transmission, which was adopted in the development of a 600 [...] Read more.
In order to improve the efficiency and convenience of wind energy storage and solve the reproducibility of the hydraulic wind turbine, we present a storage type wind turbine with an innovative hybrid hydraulic transmission, which was adopted in the development of a 600 kW storage type wind turbine experimental platform. The whole hydraulic system of the storage type wind turbine is mainly an ingenious combination of a closed loop transmission and an open loop one, which can also be divided into three parts: hydraulic variable speed, hydraulic energy storage, power generation. For the study focusing on the capture and storage of wind energy, the mathematical model of the wind turbine except for the power generation was established under MATLAB/Simulink. A double closed loop control strategy is proposed to achieve the wind wheel speed regulation and wind energy storage. The dynamic simulations of the 600 kW storage type wind turbine experimental prototype were carried out under two different input signals. The results show that the wind wheel speed achieves the desired value at fast response and high precision using the control method given in this paper, and the proposed new storage type wind turbine is reasonable and practical. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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14 pages, 2275 KiB  
Article
Development of a Two-Stage ESS-Scheduling Model for Cost Minimization Using Machine Learning-Based Load Prediction Techniques
by Minsu Park, Jaehwi Kim, Dongjun Won and Jaehee Kim
Processes 2019, 7(6), 370; https://doi.org/10.3390/pr7060370 - 12 Jun 2019
Cited by 9 | Viewed by 4317
Abstract
Effective use of energy storage systems (ESS) is important to reduce unnecessary power consumption. In this paper, a day-ahead two-stage ESS-scheduling model based on the use of a machine learning technique for load prediction has been proposed for minimizing the operating cost of [...] Read more.
Effective use of energy storage systems (ESS) is important to reduce unnecessary power consumption. In this paper, a day-ahead two-stage ESS-scheduling model based on the use of a machine learning technique for load prediction has been proposed for minimizing the operating cost of the energy system. The proposed algorithm consists of two stages of ESS. In the first stage, ESS is used to minimize demand charges by reducing the peak load. Then, the remaining capacity is used to reduce energy charges through arbitrage trading, thereby minimizing the total operating cost. To achieve this purpose, accurate load prediction is required. Machine learning techniques are promising methods owing to the ability to improve forecasting performance. Among them, ensemble learning is a well-known machine learning method which helps to reduce variance and prevent overfitting of a model. To predict loads, we employed bootstrap aggregating (bagging) or random forest technique-based decision trees after Holt–Winters smoothing for trends. Our combined method can increase the prediction accuracy. In the simulation conducted, three combined prediction models were evaluated. The prediction task was performed using the R programming language. The effectiveness of the proposed algorithm was verified by using Python’s PuLP library. Full article
(This article belongs to the Special Issue Energy Storage System: Integration, Power Quality, and Operation)
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