•OptimizatEqual contributipower flow (OPF) problem can use to determine the operating range of FACTS.•Two optimization problems based on BFM and BIM for dynamic reactive power compensation are ...compared in terms of computational time.•The total solve-time of the BFM problem is less than BIM; the time difference increases as the system size expands.•Algorithms based on BFM and BIM are applied to determine the optimal operating range of the FACTS to be installed in the future Ecuador-Peru 500 kV interconnection.
Dynamic reactive compensation using Flexible AC Transmission Systems (FACTS) in power systems allows for regulation of the voltage within limits defined by the grid operator. Optimization algorithms that solve the optimal power flow (OPF) problem can be used to determine the operating range of a FACTS device. In this paper, we compare, in terms of total solve time, the solutions of two optimization algorithms for dynamic reactive power compensation, using the Branch Flow Model (BFM) and the Bus Injection Model (BIM) to represent the power flow equations. The algorithms to solve both problems have been compared using four cases: the adapted IEEE 14-Bus System, New England IEEE 39-Bus System, IEEE 118-Bus Test System, and the authors' proposed 20-Bus SNI-500 kV Ecuadorian System. The results allow us to identify that the convergence of BFM is achieved in less solve-time concerning BIM. Furthermore, both algorithms were applied to the case study of the future Ecuador-Perú 500 kV Interconnection, obtaining that the operating range of the SVC to be installed on the Peruvian side should supply between 58 MVAr and 209 MVAr.
•Voltage stability of power grid with increasing wind energy integration is assessed.•Scenarios of wind energy penetration level (PL) up to 100% is analysed.•Maximum PL that will not lead to ...overloading of any system equipment is determined.•Line loadability enhancement measures to improve maximum PL are proposed.•Reactive power compensation can enhance voltage stability with increasing PL.
This paper presents the voltage stability assessment of power system with increasing wind energy penetration. The effects of increasing Doubly-Fed Induction Generator-based Wind Energy Conversion System (DFIG-WECS) penetration in the power system have been investigated in this work. Active Power-Voltage (PV) analysis was employed to determine the voltage stability limits in terms of the maximum loadability limit within which stable operation of the grid can be guaranteed as the wind energy penetration increases. The analyses in this work were carried out both for normal and contingency operations of the grid. IEEE 14-bus test system was used as the study case. Simulations were carried out using DigSilent PowerFactory software and results analyses were done using MATLAB. Furthermore, the effects of integrating DFIG-WECS on the loading of essential power system equipment are investigated. The results show that the maximum loadability limit of the study system increases with increasing DFIG-WECS power penetration up to 100%. However, the overloading effects on critical transmission lines presents a definitive limit to the allowable practical penetration level, which is determined to be 28.06%. This limit can be improved to 29.88%, 46.3% and 52.23% by Thyristor-Controlled Series Capacitor (TCSC) application on Line 9–14, upgrading Line 9–14 to double circuit, and upgrading both Line 9–14 and Line 13–14 to double circuit respectively. Thus, effective line enhancement and reactive power compensation strategy such as those offered by FACTS devices are required for a voltage-stable operation of the grid with increasing wind energy penetration.
Dynamic wireless power transfer (WPT) is a practical method to solve electric vehicle (EV) range anxiety and reduce the cost of on-board batteries. This paper presents a novel dynamic WPT system that ...combines the advantages of pads array and segmental long coils coupler. In the proposed circuit, several paralleled LCC reactive power compensation networks (RPCNs) in the primary side were excited by a sole inverter and the power distribution was realized automatically; an auxiliary LCC network was proposed to regulate current in the primary coil to minimize the electromagnetic interference (EMI) and reduce the system's power loss. A scaled-down prototype of a dynamic wireless charging system was developed to prove the validity of the theoretical analysis.
The analysis of voltage stability in power system networks is outlined in this document. The Fast Voltage Stability Index (FVSI) is employed to evaluate the condition of the power lines under both ...normal and critical load situations. It aids in identifying the vulnerable buses that require reactive power compensation. Reactive power compensation is achieved by utilizing a series of interconnected FACTS devices, which effectively improve the stability limit and mitigate the risk of voltage collapse in strained transmission lines. The paper showcases the effective utilization of FVSI in assessing the stability of transmission line voltages. Discussion has also taken place regarding the enhancement of bus voltage stability, improved line flows, and reduction of losses through the application of series FACTS compensation. The examinations were conducted on IEEE30, IEEE 57, and IEEE118 bus networks.
With the increased use of power electronic for ac-to-dc converters, electrical distributions systems are experiencing an increased in non-linear loads. These non-linear loads, such as the classical ...rectifier, draw non-sinusoidal currents which tend to have a deleterious impact on the power quality of the modern AC distribution systems. The interaction of non-sinusoidal currents with the grid impedance leads to distorted system voltage which can adversely impact other devices connected to the grid. The integration of distributed energy resources (DERs) with the distribution power grid can further exacerbate the harmonic power issues. The traditional methods of compensation are no longer adequate and hence it is necessary to develop a means to provide local reactive and harmonic compensation at the source of the power quality problem within the low-voltage distribution network. This article investigates the use of a capacitor-less distribution static synchronous compensator (D-STATCOM) for power quality compensation in modern distribution systems. The proposed topology is based on a matrix converter (MC), controlled by finite control set model predictive control (FCS-MPC) which makes possible the use of inductive energy storage rather than electrolytic capacitors, which have been proven to be the most failure-prone components in a power electronic circuit. Simulation and experimental results are presented to validate the effectiveness of the approach.
•Capacitor-less D-STATCOM proposed to improve power quality in distribution network.•7.5KVA experimental setup is built to test the proposed technology.•Technology is based on matrix converter controlled with model predictive control.•Proposed Technology is capable of harmonic compensation and power factor correction.•The proposed technology is suited for application in regions with hot/arid climate.
The main aim of the static Transmission Network Expansion Planning (TNEP) is to determine which and where new transmission equipment must be installed. The complexity added by the non-linearities ...leads to simplifications, which include the DC model. However, most non-linearities are solvable nowadays. Thus, the new scenario of large non-dispatchable power sources penetration and the several developments in technologies, e.g, Flexible AC Transmission Systems (FACTS) devices and High Voltage Direct Current (HVDC) interconnections, motivate the use of the AC model with its non-linearities. Some research works address the use of some of those technologies for TNEP in an independent fashion, which can lead to sub-optimal solutions. In this work, Voltage Source Controlled-Multiterminal HVDC (VSC-MTDC) systems, FACTS devices, and Reactive Power Planning (RPP) are integrated into the same planning optimization process, so that a unified AC TNEP formulation is proposed. A non-linear mathematical programming technique and a differential evolution based metaheuristics are chosen to achieve an optimal transmission configuration. To evaluate the benefits of the proposed approach, two IEEE modified test systems (9 and 118 buses) are used. Results suggest that more economical solutions can be obtained if different types of reinforcement strategies are taken into account in a unified approach.
•TNEP problem with a unified formulation for several transmission equipment.•The model and approach allow greater flexibility in the TNEP process.•Different types of reinforcements in the same expansion process.
Distributed generation (DG) penetration in a system may affect power quality, and energy efficiency, if it exceeds a particular value, known as the system's hosting capacity (HC). In this work, a ...comprehensive overview of hosting capacity and harmonic distortion limits is presented and discussed. The highest allowable penetration level of photovoltaic (PV)-based distributed generation units, hosted on typical industrial distribution systems, was analyzed in terms of the three power quality and energy efficiency performance parameters, namely bus voltage limits, line ampacities, and harmonic distortion limits. The analytical results show that the system's HC decreases with increase in utility side's background voltage distortion and load side's nonlinearity values. The HC level was affected more by the nonlinearity of the load side than by the utility side's background voltage distortion. Therefore, a single-tuned passive filter is suggested for maximizing the system's limited HC. Further, an optimization algorithm was developed to find simultaneously the system's HC and the parameters of the proposed filter, by considering the three performance parameters as constraints. The proposed filter design was found to attain a better level of HC than what can be obtained with a traditional filter design, based on current demand distortion minimization.
It has been demonstrated theoretically and experimentally that the Vehicle-to-Grid (V2G) enabled electric vehicle (EV) charger is of a reactive power compensation ability with a battery or capacitor ...connected. To exploit the aggregated reactive power V2G abilities of massively dispersed EV chargers, a distributed model predictive control (DMPC) strategy applying to both balanced and unbalanced distribution networks (DNs) is proposed to integrate them into real-time DN voltage regulation. Firstly, based on the instantaneous power theory and voltage sensitivity matrices, a voltage regulation model considering the reactive response of EV chargers is established without violating the normal EV active charging demands. Then, a completely distributed framework is achieved by DMPC, in which prediction information and calculation results are shared in a Peer-to-Peer (P2P) way to realize the asynchronous broadcast. The proposed model and techniques are validated by numerical results obtained from the IEEE European low voltage test feeder system. The case studies indicate that the proposed DMPC is robust to communication latency (CML) and works effectively in both balanced and unbalanced DNs without any control center, which is a significant advantage for the promotion of real-time reactive power V2G in DNs with irregular user integration and relatively poor communication infrastructure.
•Optimal planning of charging stations (CS) along with capacitors (CAP).•Proposed technique is quantum-behaved Gaussian mutational DA (QGDA).•Parking lot and capacitor allocation is suggested for ...congestion management.In order to optimally determine the parking lot size, QGDA is utilized.
In this paper, a new methodology for optimal planning of charging stations (CS) along with capacitors (CAP) using proposed technique is presented. In order to achieve a better balance between exploration and exploitation for dragonfly algorithm (DA), the quantum-behaved and Gaussian mutation strategies on the performance of DA is used. This is the novelty of our proposed work. Hence, it is named as quantum-behaved Gaussian mutational DA (QGDA). Here, parking lot and capacitor allocation is suggested for congestion management along with reactive power compensation. In order to optimally determine the parking lot size, QGDA is utilized. The effectiveness of the proposed technique is tested on adapted IEEE 34-bus distribution network. The result attained by QGDA technique is compared with existing techniques such as PSO and BBO. With PL, the proposed technique achieves the Ploss and Qloss of 25.61 kW and 25.99KVar. PL and C at same node, the proposed technique achieves the Ploss and Qloss of 31.09 kW and 32.88KVar. PL and C at different node, the proposed technique achieves the Ploss and Qloss of 25.09 kW and 26.98KVar. Furthermore, the proposed results show that an uneven EV charging scenario can cause significant voltage unbalance that goes beyond its allowed limit of 2%.
This article proposes a multiple frequency spectrum impedance matching method to extend the applying environment of the impedance matching technology from linear sinusoidal voltage to nonlinear ...voltage in the electromagnetic method (EM) of geological survey. First, the impedance characteristics of the transmitter, antenna, and load are analyzed to prepare for impedance matching. Second, based on the effect analysis of different impedance matching connection methods, a nonlinear multiple frequency spectrum impedancematching topology (NMIM) is proposed for nonlinear power amplifiers. Third, the optimized parameters design methods of the proposed topology and its load recognition-based control strategy are proposed for good nonlinear matching performance. At last, the dynamic hardware experiments validate the effectiveness of the proposed matching method and its control strategy. The results show that the proposed NMIM can match the impedance of the antenna and load dynamically to increase the amplifier emission current amplitude by over 21% and power capacity utilization rate by over 37% on average, which is at least 12% better than the results of the previous impedancematchingmethod.
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