Since wave fluctuates continuously, the forecast of the wave energy is very important for the operation of power systems integrated with large-scale wave energy generation. A combined model of day-ahead wave energy forecast based on improved grey BP neural network (BPNN) and modified ensemble empirical mode decomposition (MEEMD) -autoregressive integrated moving average (ARIMA) is proposed in this

An experimental and numerical time-domain analysis of the early electric response of two kw-class Vanadium Redox Flow Batteries (VRFBs) under different state of charge, electrolyte flow and load is presented. The numerical analysis resorted to an equivalent circuit whose parameters were identified from electrochemical impedance spectroscopy measurements. Two discharge modes were investigated: natural

With the rapid growth of wind power penetration in power grid, the system operators need to implement the grid specification of wind farm participating in primary frequency regulation (PFR). In this paper, a double-layer control framework based on permanent magnet synchronous generator (PMSG) is proposed, which can simulate the inertia and droop characteristics similar to thermal units. The top-layer

Although the integration of solar photovoltaic (PV) systems is gaining widespread acceptance, the intermittency and instability of PV power generation lead to several operational challenges. PV power generation can be impacted by multiple environmental factors, such as the soiling of solar PV panels. There are some conventional methods proposed to deterministically estimate the solar power loss caused

This article proposes a coordinated operation strategy for a virtual power plant (VPP) with multiple DER aggregators under the wholesale energy and regulation service market. Considering the market clearing process, VPP operation profit, and DER aggregators’ interests, a tri-layer hierarchical framework for VPP is developed to formulate the bidding plans to the superordinate market operator and the

Thermostatically controlled load (TCL, such as heating, ventilation, and air conditioning system) is a desirable demand-side flexibility source in distribution networks. It can participate in regulation services and mitigate power imbalances from fluctuating distributed renewable generation. To effectively utilize the load flexibility from spatially and temporally distributed TCLs in a distribution

In response to the automatic generation control (AGC) signals, the direct power control of a large-scale PV power plant easily encounters the communication bottlenecks, the high optimization difficulty and computation burden due to the large number of controllable inverters with different response performances. To handle these problems, a hierarchical framework of coordinated power control (CPC) is

With the increase in wind generation installed capacity, the uncertainty of wind power has brought great challenges to wind power accommodation. The accurate assessment result of wind power accommodation capability (WPAC) has important guiding significance to the formulation of the day-ahead wind power trading plan for the multi-energy microgrid (MEMG). This paper proposes a WPAC assessment method

This letter proposes an enhanced sufficient battery model (ESBM) as well as a binary search algorithm for an improved inner-approximation of the aggregate flexibility of thermostatically controlled load (TCL) arrays. Compared with the previous work on generalized battery models, our ESBM preserves the merits of being sufficient and reduces conservativity. Moreover, unlike the works ignoring the coupling

Power system inertia helps the grid to maintain frequency stability. However, as photovoltaic (PV) generation continuously displaces synchronous generators (SGs) and reduces system inertia, it may result in system failure. Virtual inertia control (VIC) technology has drawn increasing attention because it enables PVs to increase system inertia by mimicking the characteristics of SGs. Energy sources

Concerning the difficulty in unified modeling of direct-drive wind farm with virtual inertia and the unknown cause of low frequency oscillation, a detailed model of integrated dissipation energy of direct-drive wind farm is built. First, the dissipation energy model of wind generator and the integrated dissipation energy model of direct-drive wind farm containing virtual inertia and PLL is derived

Multiple wind farms (WFs) should be spatially and temporally coordinated during inertial control to avoid the under- or over-power supply. For this purpose, we propose a second-order cone predictive model to exploit the optimal inertial control scheme (ICS) of multiple WFs for under-frequency and over-frequency events. Specifically, we firstly build the nonlinear predictive model including the predictive

The demand for wind turbines has been ultimately increased over the last decades. Accordingly, the power converter controller plays the primary role in extracting energy out of the generator, using efficient and reliable techniques as Maximum Power Extraction (MPE) and delivering the power to the grid. This research pursues to present a Cascade-Forward Neural Network (CFNN) MPE that maintains the MPE's

The ever-growing higher penetration of distributed energy resources (DERs) in low-voltage (LV) distribution systems brings both opportunities and challenges to voltage support and regulation. This paper proposes a deep reinforcement learning (DRL)-based scheduling scheme of energy storage systems (ESSs) to mitigate system voltage deviations in unbalanced LV distribution networks. The ESS-based voltage

Distinct characteristics of transmission and distribution power grids typically necessitate different control algorithms, especially at the primary control level where quick responses are required. Accordingly, various droop control schemes have been developed due to specific types of power grid impedances. Therefore, controllers at higher levels often have to be redesigned whenever a different power

A community integrated energy system (CIES) with an electric vehicle charging station (EVCS) provides a new way for tackling growing concerns of energy efficiency and environmental pollution, it is a critical task to coordinate flexible demand response and multiple renewable uncertainties. To this end, a novel bi-level optimal dispatching model for the CIES with an EVCS in multi-stakeholder scenarios

Flexibility helps accommodate uncertainties from the increasing renewables, such as wind power generation (WPG), but limited to scheduling methods, flexibility potentials of the power system have not been fully realized. This paper proposes the mathematical formulation and novel transformation for flexibility-enhanced continuous-time stochastic scheduling (FE-CTSS) of the power system under wind uncertainties

The conventional volt-watt control method used in PV inverters to overcome the over-voltage problems can result in significant unfairness in the curtailed active power in PV-rich distribution networks. In this paper, a novel decentralized control strategy is presented to improve fairness in the curtailed active power of inverters. In this strategy, first, each PV inverter calculates the ratio of its

Optimal dispatch of modern power systems often entails efficiently solving large-scale optimization problems, especially when generators have to respond to the fast fluctuation of renewable generation. This paper develops a method to learn the optimal strategy from a mixed-integer quadratic program with time-varying parameters, which can model many power system operation problems such as unit commitment

In this paper, an Improved Social Ski Driver based MPPT algorithm (ISSD-MPPT) has been proposed. Single dynamic tuning parameter making the algorithm implementation simpler as compared to the others. Besides, the ISSD-MPPT also increased the convergence speed (CS) by 38.75% compared to the conventional Social Ski Driver algorithm (SSD). Then, a new approach to increase the response speed during load

In this paper, a novel voltage equalization technique based on the hybridization of total cross-tied configuration and switching capacitor concept for enhancing the power generation of PV arrays during partial shading is proposed. The technique uses the charge balancing concept to maintain the voltage ratio between the total cross-tied array modules and ensures higher power output and convex power

The two-settlement electricity markets are widely accepted. In current practice, the markets are cleared based on locational marginal prices. However, this market clearing scheme leaves arbitrage opportunities between day-ahead and real-time markets for strategic distribution system operators (DSOs). They can submit biased bids from their actual load forecasts in the day-ahead market for additional

In modern power systems, small distributed energy resources (DERs) are considered a valuable source of flexibility towards accommodating high penetration of Renewable Energy Sources (RES). In this paper we consider an economic dispatch problem for a community of DERs, where energy management decisions are made online and under uncertainty. We model multiple sources of uncertainty such as RES, wholesale

The temporal dependencies of wind power are significant to be involved in the modeling of short-term wind power forecasts. However, different time series inputs will contribute differently to the forecasting performance and bring in challenges to the selection of the relevant driving information. In this paper, a Multi-Source and Temporal Attention Network (MSTAN) is proposed for short-term wind power

Energy storage unit (ESU) is playing an increasingly important role in load shifting and uncertainty mitigation. This paper aims to quantify the value of ESU in the unit commitment (UC) with renewable generation. By treating the power and energy capacities of ESU as continuous parameters, the stochastic UC problem is cast as a multi-parametric mixed-integer linear program (mp-MILP), whose optimal value

Wind farm multiple aggregated power curve modeling plays an important role in reducing the complexity of analyses in wind farm management and annual power prediction. There is a trade-off between the complexity and accuracy of aggregated power curves. In this paper, $K$ -Means clustering is utilized to classify turbines in a wind farm into homogeneous groups according to a new set of features based

To address the increasing impact of extreme temperatures (ETs) on the power system and electricity supply, demand response (DR) programs are widely used to reduce peak demands at ETs. The customized pricing mechanisms are required for an effective DR to target the potential consumers accurately. This paper proposes a frequency control ancillary service and critical peak rebate (FCAS-CPR) strategy based

This paper develops a novel demand side management (DSM) approach to incorporate in optimal sizing of solar photovoltaic (PV), wind turbine (WT), and battery storage (BS) for a standalone household. The DSM strategy is based on the state-of-charge level of battery and day-ahead forecasts of solar insolation and wind speed. The core of the DSM is a fuzzy logic method which decides for efficient load

In this paper, the coupling mechanism of phase-locked loop (PLL)-synchronized multiparalleled wind farms under grid faults is analyzed in detail. First, the coupling effects of the currents and the equivalent power angles (EPAs) among wind farms are identified by analyzing the voltage characteristics during low voltage ride-through (LVRT). Subsequently, a transient stability assessment method is proposed

This paper proposes a hybrid control method based on model predictive control (MPC) and iterative learning control (ILC) for the hybrid energy storage system (HESS) in the application of islanded microgrid with photovoltaic (PV) generation. The hybrid method helps to deal with the sudden change in generation and load power demands. MPC aims to regulate the current of the battery and the supercapacitor

This work introduces an anti-windup feedback second order generalized integrator (AWFSOGI) based direct power control for voltage source converter (VSC) in the grid integrated solar photovoltaic energy conversion system, for dynamic control of active and reactive powers fed into the grid. The primary aim of the control is to extract fundamental component from distorted grid conditions and to feed the

Wave energy converters with capacity similar to, or greater than, wind turbines are desirable for the supply of electricity to the grid. It is shown that this may be provided by multiple floats in a hinged raft-type configuration with multi-mode forcing. The case analysed has 8 floats and 4 power take off (PTO) units. Analysis is based on linear diffraction-radiation modelling, validated in wave basin

Hybrid AC/DC microgrids allow the integration of diverse renewable energy resources. However, the security and the reliability of hybrid AC/DC microgrid systems are challenged by various contingencies. In this paper, we propose a BESS sizing and siting approach which uses a combined stochastic programming and robust optimization method to cope with uncertainties of loads, wind power generation, and

The increasing penetration of distributed energy resources (DERs) may cause security and economic risks in the distributed network. In this paper, the optimal allocation of battery energy storage systems (BESS) is proposed to mitigate the risks in the radial distribution network by considering future uncertainties, such as the uncertainties of load and renewable energy. The interacting levels of the

The frequent switching operations and triggering events of automation devices are poorly documented in distribution management systems, leading to challenging work regarding the timely detection of system state changes. Additionally, the limited measurements in distribution networks and the randomness of plug-and-play devices make obtaining real-time observations of system states difficult. Furthermore

A new methodology is derived to transform between an ideal zero-turbulence power curve and practical power curves representing wind turbine performance in irregular winds. The derivation is based on substituting a theoretical distribution of the wind process in place of a single mean wind speed, truncating the wind-speed distribution at the rated power of the turbine, and then applying random process

Coordinated operation of several industrial energy hubs (IEHs) to realize local energy management concepts at strategic points like industrial parks has attracted the attention of power grid operators worldwide. Deriving an operational model for integrating a large set of IEHs to trade energy in various markets is a fundamental challenge that has not yet been addressed. To overcome this research gap

Small-signal stability issues of the voltage source converters (VSC) connected weak-network during asymmetric faults is currently rarely studied. This paper develops mathematic model of VSC system during weak-grid asymmetric faults, which reveals dynamic coupling between the phase-locked loop (PLL) and both positive-sequence (PS) control system and negative-sequence (NS) control system. Based on the

We propose a two-stage probabilistic solar power (SP) forecasting algorithm to utilize the solar irradiation (SI) observations measured from different locations. In the first stage, we predict the SI based on the numerical weather prediction (NWP) after interpolating SI observations. Since the SI on the target location is not measured, we interpolate it using the spatio-temporal Kriging technique based

With the high penetrations of diverse renewable energy resources and energy storage devices, the optimal planning of microgrids based on selected representative operating periods (ROPs) are facing significant challenges. This paper proposes a full data-driven planning method to cope with such challenges. The proposed method takes the full data, which contain all the information on load and meteorological

The rapid integration of variable generation (VG), such as photovoltaics (PV), necessitates an increase in the secondary frequency regulation (SFR) to handle the system intra-dispatch interval imbalance because of VG's variation. Although PV has the control capability to provide SFR, the main challenge is in guaranteeing the delivery of PV's energy and SFRs capacities in the automatic generation control

In this paper, a dynamic average consensus-based distributed fixed-time secondary control scheme is proposed for an islanded DC microgrid, to achieve both current sharing among the converters and voltage regulation of the DC bus within a fixed settling time. The secondary controller is designed using sign functions and fraction-based feedback signals for accelerating the convergence. To release the

With the increase of offshore wind farm size, the use of classical analytical reliability methods becomes computationally intractable. This paper proposes a holistic approach combining multi-state Markov processes and the universal generating function for the availability assessment of radial large-scale offshore wind farms. The proposed model combines multi-state wind turbine output, wind turbine

This paper presents a trilevel risk-averse strategy to configure the grid-scale energy storage systems (ESS) in active distribution network. Unlike the traditional planning framework, which presumes that ESS and renewable energy sources (RES) are cooperatively planned, we consider a practical situation that the siting choice of individual RES owners could be conflict with systems operation target of

This paper proposes a three-stage unit commitment model for the market operation of transmission and distribution coordination under the uncertainties of renewable generation and demand variations. The first stage is for the independent system operator (ISO) that determines the commitment decisions of the transmission-level generators and the distribution-level system reconfiguration; the second stage

This paper presents a novel robust current droop controller (RCDC) using a single droop loop. This scheme is unified supporting dual mode of operation for micro-grids (MGs), including grid connected mode (GCM) and islanded mode (ISM) while ensuring seamless transition between the two modes with proportional power sharing maintained. The proposed controller is further incorporated with an improved maximum

This paper presents a grid-forming control (GFC) scheme for two-stage photovoltaic (PV) systems that maintains power reserves by operating below the maximum power point (MPP). The PV plant in GFC mode behaves like a voltage source that supports the grid during disturbances in full or limited grid-forming mode as per the reserve availability. This is a model-free method that avoids the estimation of

In this paper, we propose a distributed model predictive control (MPC) scheme for economic dispatch of energy systems with a large number of active components. The scheme uses a distributed optimization algorithm that works over random communication networks and asynchronous updates, implying the resiliency of the proposed scheme with respect to communication problems, such as link failures, data packet

With the recent advancements in power electronics for wind turbines (WTs) and increasing penetration of wind energy, wind power plants (WPP) have become necessary contributors of reactive power support for the bulk power system. Balancing reactive power support with individual WT operating requirements in a cost-effective manner is a challenge for WPP designers. In this paper, we present a methodology

In this paper, the mechanism of energy storage (ES)-based power oscillation damping is derived by the small signal and the classical electric torque method. And then, by cooperating PI with an integral reduction loop, a controller is designed to form a novel PI-IR controller to guarantee that the energy variation of ES damper is zero at the end of one oscillation. Furthermore, for the controller parameters

This paper proposes a comprehensive method to estimate non-synchronous inertia in an AC microgrid system by analyzing measured frequency transients. Non-synchronous inertia includes inertial support from various inverter-interfaced renewable energy sources and energy storage devices in the form of virtual or emulated inertia. In the proposed method, a multi-step approach is used to identify a matrix

Restructuring and privatization in power systems have resulted in a fundamental transition of conventional distribution systems into modern multi-agent systems. In these structures, each agent of the distribution system would independently operate its local resources. In this regard, uncertainties associated with load demands and renewable energy sources could challenge the operational scheduling conducted

Inclusion of bypass diodes at the output terminal of the PV array mitigates the effect of partial shading (PS) but causes multiple peaks of power at the output. The conventional hill climbing and perturb and observe algorithms cannot track the optimal point during partial shading phenomena for multiple peaks corresponding to the different shading pattern on the Power-Voltage (P-V) curve. Fuzzy logic

Robust scheduling for an integrated electricity and heat system (IEHS) is essential to hedge the uncertainties brought by volatile wind power and heat load that could pose critical security threats to IEHS operation. Because of the distributed structure of different energy sectors, their models are managed locally and private information must be protected. In this context, a decoupled solution is favorable

Relying on the power flexibility of distributed energy resources (DERs) located in an active distribution network (ADN), this ADN will be able to provide power flexibility to the upper-layer grid at their point of common coupling (PCC). The power flexibility is defined as additional bi-directional active/reactive powers a resource can provide to the grid by adjusting its operating point. In this context

The volatile nature of wind power generation creates challenges in achieving secure power grid operations. It is, therefore, necessary to accurately predict wind power and its uncertainty quantification. Wind power forecasting usually depends on wind speed prediction and the wind-to-power conversion process. However, most current wind power prediction models only consider portions of the uncertainty

Small wind turbines (SWTs) are promoted to be used in urban areas to mitigate the carbon footprint and expensive upgrades expected from high penetration levels of fast charging stations (FCSs). In this paper, a planning framework is proposed to amplify the total benefit for the owners of FCSs and SWTs as well as local distribution companies (LDCs). A stochastic program is developed to site and size

With the increasing wind power integration, the security and economy of the power system operations are greatly influenced by the intermittency and fluctuation of wind power. Due to the flexible operational modes for charging/discharging, the hybrid energy storage system (HESS) is composed of battery energy storage system and super-capacitor can effectively mitigate the wind power uncertainty. This

In this paper, a novel deep convolutional recurrent network method, the K-shape and K-means guided Convolutional Neural Network integrating Gated Recurrent Units (KK-CNN-GRU), for short-term multi-step ahead predictions of wind turbine power generations is proposed. The KK-CNN-GRU is composed of three modules, an input tensor construction module, a two-layer clustering module, and a prediction module

The distributed control of DC microgrid is becoming increasingly important in modern power systems. One important control objective is to ensure DC bus voltage stability and proper current sharing with a reduced communication burden. This paper presents a new event-triggered distributed secondary control strategy for single-bus DC microgrid. Through this strategy, both current sharing and bus voltage