High Penetration Of Wind Turbines Research Articles

Guest editorial: Application of cloud energy storage systems in power systems

Guest editorial: Application of cloud energy storage systems in power systems

PSO-Based Model Predictive Control for Load Frequency Regulation with Wind Turbines

With the high penetration of wind turbines, many issues need to be addressed in relation to load frequency control (LFC) to ensure the stable operation of power grids. The particle swarm optimization-based model predictive control (PSO-MPC) approach is presented to address this issue in the context of LFC with the participation of wind turbines. The classical MPC model was modified to incorporate the particle swarm optimization algorithm for the power generation model to regulate the system frequency. In addition to addressing the unpredictability of wind turbine generation, the presented PSO-MPC strategy not only addresses the randomness of wind turbine generation, but also reduces the computation burden of traditional MPC. The simulation results validate the effectiveness and feasibility of the PSO-MPC approach as compared with other state-of-the-art strategies.

Frequency‐constrained energy and reserve scheduling in wind incorporated low‐inertia power systems considering vanadium flow redox batteries

AbstractThis paper proposes a novel energy and reserve scheduling model for power systems with high penetration of wind turbines (WTs). The objective of the proposed model is to minimize the total operation cost of the system while static and dynamic security is guaranteed by preserving the frequency nadir, RoCoF, and quasi‐steady‐state frequency in the predefined range. Likewise, a supervisory, control, and data acquisition (SCADA) system is developed which allows Vanadium Redox Flow Batteries (VRFBs) to continuously communicate and participate in the primary frequency response. To cope with the uncertainties, adaptive information gap decision theory is used that ensures a target operating cost for the risk‐averse operator of the power system. The proposed scheduling model is applied on a modified IEEE 39 bus test system to verify the impacts of the fast reserve provided by the VRFBs in the dynamic frequency security enhancement of the power system with high penetration of WTs.

Specified time consensus control of ESSs for frequency support with DFIG wind turbines

Small scale energy storage systems (ESSs) can assist grid integration of doubly fed induction generators (DFIG), potentially in power system frequency regulation. However, the extensive communication between ESSs may cause frequency response delays and may deteriorate the performance. Thus, this paper aims to propose a frequency response scheme with ESS assisted DFIGs wind turbines (WTs) via a specified time consensus (STC) approach. The load frequency control model with high penetration of WT is firstly constructed. A delay margin estimation (DME) procedure is conducted afterwards to estimate the allowable time delays for the system to provide frequency response. Meanwhile, the coordination strategy of the WTs and the ESSs is proposed for load sharing among the WT-ESS. Subsequently, the STC control for the ESSs is proposed to achieve consensus among the ESSs within a specified time requirement induced by the delay margin. Simulations are conducted to validate the effectiveness of the proposed method. The simulation results show that the DME is meaningful for shaping the allowable system time delay; the STC control can effectively smooth the power output of WTs and enhance the frequency regulation capability; comparing with conventional methods, the novel method shows faster convergence speed and better frequency regulation performance.

Evaluation of hydrogen storage technology in risk-constrained stochastic scheduling of multi-carrier energy systems considering power, gas and heating network constraints

The operation of energy systems considering a multi-carrier scheme takes several advantages of economical, environmental, and technical aspects by utilizing alternative options is supplying different kinds of loads such as heat, gas, and power. This study aims to evaluate the influence of power to hydrogen conversion capability and hydrogen storage technology in energy systems with gas, power, and heat carriers concerning risk analysis. Accordingly, conditional value at risk (CVaR)-based stochastic method is adopted for investigating the uncertainty associated with wind power production. Hydrogen storage system, which can convert power to hydrogen in off-peak hours and to feed generators to produce power at on-peak time intervals, is studied as an effective solution to mitigate the wind power curtailment because of high penetration of wind turbines in electricity networks. Besides, the effect constraints associated with gas and district heating network on the operation of the multi-carrier energy systems has been investigated. A gas-fired combined heat and power (CHP) plant and hydrogen storage are considered as the interconnections among power, gas and heat systems. The proposed framework is implemented on a system to verify the effectiveness of the model. The obtained results show the effectiveness of the model in terms of handling the risks associated with multi-carrier system parameters as well as dealing with the penetration of renewable resources.

A New Guideline for Security Assessment of Power Systems with a High Penetration of Wind Turbines

By the increase of the penetration of power-electronic-based (PE-based) units, such as wind turbines and PV systems, many features of those power systems, such as stability, security, and protection, have been changed. In this paper, the security of electrical grids with high wind turbines penetration is discussed. To do so, first, an overview of the power systems’ security assessment is presented. Based on that, stability and security challenges introduced by increasing the penetration of wind turbines in power systems are studied, and a new guideline for the security assessment of the PE-based power systems is proposed. Simulation results for the IEEE 39-bus test system show that the proposed security guideline is necessary for PE-based power systems, as the conventional security assessments may not be able to indicate its security status properly.

Economic-environmental effect of power to gas technology in coupled electricity and gas systems with price-responsive shiftable loads

Abstract Integration of renewable energy sources in electrical energy networks, is significantly increased due to economic and environmental issues in recent years and has appeared new challenges in the operation of power systems. Additionally, the power to gas (P2G) technology is a practical solution for accommodating the variability of the power output of wind energy sources, which are effective in reducing pollutant gas emissions considering their gas or power injection to the network at on-peak time intervals. Moreover, natural gas (NG)-fired generation plants can be introduced as practical solutions for decreasing power output variations of renewable sources due to their high ramp rates and quick response. This study proposes a multi-objective two-stage stochastic unit commitment scheme for integrated gas and electricity networks taking into account novel flexible energy sources such as P2G technology and demand response (DR) programs as well as high penetration of wind turbines. In this paper, P2G technology is introduced as a promising option for increasing the wind power dispatch in power systems. In addition, DR program as a cost-environmental effective method is modeled as a price-responsive bidding mechanism that is influential in decreasing the operation cost of the integrated network by shifting load from on-peak time intervals to off-peak time intervals. The introduced scheme has been implemented on an integrated 6-bus power system with 6-node gas networks by analyzing the performance of the framework in terms of operation cost and release of environmental pollutant gases. The results show that the simultaneous consideration of power-to-gas technology and demand response program reduces environmental pollution in addition to reducing costs. The investigation of the operation cost of the whole integrated system shows that application of both P2G and DR is beneficial in decreasing cost by 2.42% and 1.78% with respect to consideration of each of the P2G and DR, respectively.

Active power support of wind turbines for grid frequency events using a reliable power reference scheme

High penetration of wind turbines (WTs) is causing reduction of power system rotating inertia so that the power grid is becoming more vulnerable to large active power imbalances. Inertial control can be applied on WTs to increase their output power with a predefined power reference scheme. However, these approaches have adverse secondary frequency drop or very slow rotor speed recovery that may worsen the grid frequency regulation if an uncertain change such as wind drop occurs. This paper proposes a reliable power reference scheme for participation of WTs in grid frequency arrest that follows a linear trajectory as a function of rotor speed. Simulations on large-scale integrated wind farms into IEEE 9-bus and New England 39 bus systems are conducted and the results of grid frequency regulation in presence of different changes are studied and compared with other methods. Also, active power contribution of WTs in a combined emission economic dispatch form is studied. The results and comparisons with other methods show the effectiveness of the proposed power reference scheme of WTs in grid frequency regulation. They also show the importance of considering sudden changes during inertial control when designing an inertial control system. By using the proposed scheme, it is recommended to set power increment of WTs to half of power mismatch in the grid to obtain maximum frequency regulation.

Inertia response from full-power converter-based permanent magnet wind generators

With a high penetration of wind turbines, the proportion of synchronous generation in the power system will be reduced at times, thus creating operating difficulties especially during frequency events. Therefore, it is anticipated that many grid operators will demand inertia response from wind turbines. In this article, different ways for emulating inertia response in full-rated power converter-based wind turbines equipped with permanent magnet synchronous generators are considered. Supplementary control signals are added to the controller of the wind turbine to extract stored energy from the rotating mass and DC-link capacitors. Simulations in MATLAB/Simulink show that the inertia response is improved by adding a term proportional to the rate of change of frequency and by extracting the stored energy in the DC-link capacitors.

A methodology for the efficient computer representation of dynamic power systems: Application to wind parks

ABSTRACTThis contribution presents a methodology to efficiently obtain the numerical and computer solution of dynamic power systems with high penetration of wind turbines. Due to the excessive computational load required to solve the abc models that represent the behavior of the wind turbines, a parallel processing scheme is proposed to enhance the solution of the overall system. Case studies are presented which demonstrate the effectiveness and applications of the proposed methodology. Copyright © 2012 John Wiley & Sons, Ltd.

Small-signal stability of wind power system with full-load converter interfaced wind turbines

Small-signal stability analysis of power system oscillations is a well-established field within power system analysis, but not much attention has yet been paid to systems with a high penetration of wind turbines (WTs) and with large wind power plants (WPPs). A comprehensive analysis is presented, which assesses the impact of full-load converter interfaced WTs on power system small-signal stability. The study is based on a seven-generator network with lightly damped inter-area modes. A detailed WT model with all grid relevant control functions is used in the study. The WT is, furthermore, equipped with a park-level WPP voltage controller and comparisons are presented. The WT model for this work is a validated dynamic model of the 3.6 MW Siemens wind power WT. The study is based on modal analysis which is complemented with the time-domain simulations on the non-linear system.

Analysis of a variable-speed wind energy conversion scheme with doubly-fed induction generator

In the last decade, the high penetration of wind turbines into the power system has been closely related to the advancement of wind turbine technology and control. The electric system contained by a large wind turbine, as well as within an offshore wind farm with hundreds of MW power capacity, has become more and more important in the interaction between the mechanical system of the wind turbine and the main power system. Furthermore, power electronics is entering the wind turbine circuitry which improves the controllability. The work presented in this paper has the main objective of extending the ability of the existing wind turbine design tools, in order to simulate the dynamic behaviour of wind turbines and the wind turbine–grid interaction.