Increasing PV penetration significantly diminishes system inertia that affects systems' damping capability to regulate primary frequency control. Unlike wind turbine, PV energy system is incapable of providing under-frequency support because of no stored kinetic energy and could cause penalties for violating regulatory requirements. Therefore, a droop-type, lead-lag controlled Battery Energy Storage System (BESS) with a novel adaptive SOC recovery strategy is proposed in this paper to provide additional damping, enhance the inertial ability of the system with 18.18% PV penetration and which satisfy Australian National Electricity Market (NEM) regulatory requirements. The adaptive SOC recovery aims to maintain flexible battery SOC value according to load/PV generation forecast and comply with future events such as peak PV generation or lower PV output during the passing cloud periods. The proposed adaptive SOC strategy regulates SOC based on the value of charging current and moreover, adaptive SOC recovery does not affect the maximum SOC limit for the regular network event. Simulation results demonstrate BESS efficacy in mitigating the adverse inertial impact of PV and accomplishing mandatory grid requirements. Moreover, the proposed adaptive SOC recovery shows the flexibility of BESS for SOC management planning in accordance with future events forecast.

Renewable energy sources (RES), such as photovoltaics (PV) and wind turbines have been widely applied as alternative energy solutions to address the global environmental concern and satisfy the energy demand. The large‐scale amalgamation of intermittent RES causes reliability and stability distress in the electric grid. To mitigate the nature of fluctuation from RES, a battery energy storage system (BESS) is considered one of the utmost effective and efficient arrangements which can enhance the operational flexibility of the power system. This article provides a comprehensive review to point out various applications of BESS technology in reducing the adverse impacts of PV and wind integrated systems. The key focus is given to battery connection techniques, power conversion system, individual PV/wind, and hybrid system configuration. The application of BESS is categorized into three areas, active, reactive, and active‐reactive power features. The key findings of the existing research of BESS application are summarized and discussed along with several simulation results. By taking a thorough review, this article identifies the key challenges of BESS application including battery charging/discharging strategy, battery connection, power conversion efficiency, power converter, RES forecast, and battery lifetime and suggests future research directions that could be explored during the design, operation, and implementation of BESS technology in the power system.

Summary Electric vehicles (EVs) and smart grids are gradually revolutionising the transportation sector and electricity sector respectively. In contrast to unplanned charging/discharging, smart use of EV in home energy management system (HEMS) can ensure economic benefit to the EV owner. Therefore, this paper has proposed a new energy pricing controlled EV charging/discharging strategy in HEMS to acquire maximum financial benefit. EV is scheduled to be charged/discharged according to the price of electricity during peak and off‐peak hours. In addition, two different types of EV operation modes, ie, grid‐to‐vehicle (G2V) in off‐peak time and vehicle‐to‐home (V2H) in on‐peak time are considered to determine comparative economic benefit of planned EV charging/discharging. The real load profile of a house in Melbourne and associated electricity pricing is selected for the case study to determine the economic gain. The simulation results illustrate that EV participating in V2H contributes approximately 11.6% reduction in monthly electricity costs compared with G2V operation mode. Although the facility of selling EV energy to the grid is not available currently, the pricing controlled EV charging/discharging presented in the paper can be used if such facility becomes available in the future.

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This paper investigates the enactment of Battery Energy Storage System (BESS) and Static Compensator (STATCOM) in enhancing large-scale power system transient voltage and frequency stability, and improving power export capacity within two interconnected power systems. A PI-lead and lead-lag controlled BESS is proposed for multimachine power system to provide simultaneous voltage and frequency regulation within the defined battery state-of-charge (SOC) ranges and an equivalent Finnish transmission grid is used to evaluate the system performance. According to Australian National Electricity Market (NEM) grid requirements, the performances of the proposed control schemes are compared with conventional PI controlled BESS and STATCOM under multiple temporary and permanent fault conditions. In addition, two adjacent disturbance events are also applied to evaluate system performance with BESS and STATCOM. Through simulation results, it is shown that when there is a 44% increase in power export and the STATCOM fails, incorporating BESS improves the performance and justifies the novelty of this study. Moreover, the proposed lead-lag controlled BESS manifests better transient performance than BESS with PI-lead and traditional PI controller, in the event of divergent temporary and permanent faults.

In a microgrid (MG), employing conventional fixed droop gain control of wind turbine for mimicking conventional generators may threaten grid stability. In this paper, an integrated control strategy of inertia emulation and dynamic sectional droop control for generating active power reference of the wind power system is presented to provide primary frequency control (PFC) services. The dynamic sectional droop is implemented with the fuzzy logic controller (FLC) regulated pitch angle control mechanism and compared with the conventional proportional-integral (PI) pitch angle control method in the isolated MG. Two different gain values are selected for developing the proposed sectional droop control which is based on the sensitivity of frequency deviation in comparison to the single fixed gain in conventional droop control. The maximum power margin of wind turbine is considered as 25% and 15% for a wind speed higher than (or equal to) the rated speed and lower than the rated speed, respectively. The effectiveness of the proposed method is investigated through Matlab/Simulink based real-time simulation studies. Simulation results demonstrate that the proposed sectional droop control provides superior performance than conventional fixed-gain method and achieves optimum frequency regulation at the rated wind speed and even for a wind speed lower than the rated wind speed.

Renewable energy sources (RES) based distributed generation (DG) system results reduction of overall system inertia, which is likely to generate higher oscillations in the system during disturbance conditions. Therefore, DG penetration level has a significant impact on system stability and reliability. This study provides an in-depth analysis of Battery Energy Storage System (BESS) impact in providing primary frequency control to support increased wind penetration level. The BESS is modeled as a storage system with DC/AC converter and other associated power electronics interfaces. The objective is to replace the existing synchronous generator in proportion with the increasing penetration level of wind units while maintaining power system stability and reliability. The BESS model is developed in DigSILENT/PowerFactory and the system performances are simulated and compared with and without the BESS considering different disturbances such as single-phase-to-ground fault, and temporary line outage and load demand increment with various DG penetration level. It is shown through simulation results that BESS exhibits the ability to reduce system oscillations following disturbances and supports the increment of DG penetration level in the existing power system. Therefore, BESS can be seen the most viable measure of stability enhancement with renewable oriented sustainable future electric grid.

To deal with the technical challenges of renewable energy penetration, this paper focuses on improving the grid voltage and frequency responses in a hybrid renewable energy source integrated power system following load and generation contingency events. A consolidated methodology is proposed to employ a battery energy storage system (BESS) to contribute to voltage regulation through droop-type control and frequency regulation by assimilated inertia emulation (IE) and droop-type control. In addition, a novel frequency-dependent state-of-charge (SOC) recovery (FDSR) is presented to regulate BESS power consumption within the FDSR constraints and recharge the battery during idle periods whenever needed. The efficacy of the proposed BESS controller is demonstrated in an IEEE-9 bus system with a 22.5% photovoltaics (PV) and wind penetration level. The simulation results obtained manifest the satisfactory performance of the proposed controller in regulating simultaneous voltage and frequency in terms of lower rate of change of frequency and better frequency nadir. Furthermore, the proposed FDSR demonstrates its superiority at the time of SOC recovery compared to the conventional approach.