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Existing voltage control schemes of cascade on-load tap changers (OLTCs) have been developed considering unidirectional power flow. However, in recent years, integration of distributed generation such as solar and wind power to the grid has created possibility for bidirectional power flow resulting in inefficiency of previous voltage control methods of cascade OLTCs. In this paper, an effective method...
A methodology to automate and control a small-scale combined heat and power system (micro-CHP) is proposed. The contribution of this design is to extend the original plant toward micro-CHP system modeling, thus allowing flexible and efficient system through graphical programming. The automation involves the synthesized system analysis; thereby, human intervention is reduced. It builds on LabVIEW™...
To mitigate the adverse effects of DGs' integration on the operation of distribution network and allow for the multi agent nature, a voltage regulation method for the active distribution network was proposed. Based on the model of each player and nodal power market, the method was modeled as a generalized Nash game. The game was converted to a bi-level optimization problem, where the active distribution...
An assessment of parameter observability to identify an equivalent wind power plant model is proposed in this paper. The trajectory sensitivity method is used as an updating rule to iteratively improve the estimation of the model parameters. The difficulties for obtaining the correct estimation are analyzed and a strategy to overcome those problems are highlighted. In general those problems are related...
The Hysteresis current control (HCC) is a popular modulation technique used in active power filter (APF) applications owing to its simplicity of implementation, fast current response and peak current limiting capability. Despite these advantages, it has a major disadvantage when applied to three-phase isolated neutral point (INP) systems: interphases dependency causes very high-switching frequencies...
High Temperature Superconducting (HTS) machines offer several benefits over the conventional machines. With the advent of YBCO materials, research and development in HTS applications has gained significant impetus. The application of flux pump has its own advantages over the conventional mechanism for magnetic field generation in superconductors. This paper reviews few relevant works and presents...
In this paper, a fault localization method for MV distribution network is investigated. The development of the method is done in a smart grid context with the deployment of voltage sensors spread along the network. The method is based on RMS voltage measurements. First the fault section is identified with the comparison the voltage slope between the successive sections. Then voltage profiles upstream...
Due to high power in-feed from photovoltaics, it is expected that more battery systems will be installed in the distribution grid in near future. In this paper, we present a method to optimally control multiple battery sets in real-time to collectively provide services to power systems. The method is based on a Model Predictive Control (MPC) framework that tries to track an aggregated signal, while...
Extreme weather may have a significant influence on the resilience of transmission systems. However, modelling the impact of weather is very challenging due to its stochastic and unpredicted nature and behaviour. To cope with these challenges, this paper presents a Sequential Monte Carlo based time-series model for evaluating the effect of weather on power system components, with focus on the wind...
The classical equal area criterion in the power-angle domain, which is typically used for power systems planning/stability studies, is modified to the time domain for out-of-step protection. Wide-area measurements are necessary to obtain the power-angle information if the traditional equal area criterion is applied for out-of-step detection. However, its time-domain modification requires only the...
A demand response program designed to mitigate peak load during hot summer days has been designed. Pacific Northwest National Laboratory (PNNL) developed taxonomy distribution feeder has been used to evaluate the effectiveness of the demand response program. The simulation includes direct load control, dynamic price control, residential PV penetration and their comparisons. The results will help guide...
The large-scale integration of stochastic generation requires additional operating reserves to cope with the uncertainty in power system operation, due to the large forecast error with existing methodologies. Previous research shows that allocating power reserves dynamically according to conditional distribution of power forecast error would benefit the generation scheduling in day-ahead electricity...
The problem of voltage regulation, at transmission level, remains pivotal for the economic and secure dispatch of power in large power systems. In this paper, we present a multivariable, Model Predictive Control based scheme for the coordination of reactive power reserves, for secondary voltage regulation. The proposed scheme is validated using a 23-generator equivalent model of the Nordic power system...
This paper demonstrates the influence of the fault arc on the magnitude of the fault current for single phase to ground faults in underground power cables. A method is suggested which allows incorporation of this impact in practical fault current calculations. Earth faults in underground cable networks depend on many parameters and are therefore complex to model and calculate exactly. Field measurements...
The unstable output of renewable energy sources, such as wind turbines or photovoltaics, causes various issues in power system operation. With a large number of renewable energy sources, it is well known that the supply and demand balance control becomes a difficult issue. In addition, together with the progress of the electric power deregulation, the power flow problem will be more complex and important...
This paper presents a nonlinear controller for a permanent-magnet synchronous generator (PMSG) wind turbine system in the framework of port-controlled Hamiltonian system. For the simplification, this work focuses on the nonlinear control law of the grid side converter (GSC) that is directly connected to the grid and affected during network disturbances. The proposed controller is designed through...
The use of distributed generation and demand response programs in smart grids implies management and integration of these resources when they are interconnected with the main power system. In the present paper, it is defined a methodology that can be used by the Virtual Power Player in order to aggregate and schedule the resources. The aggregated producers and consumers are optimally managed, making...
The impact of the increasing connection of distributed generation to medium voltage (MV) distribution feeders, with particular reference to photovoltaic (PV) units, justifies the application of an adaptive control of voltages and reactive power flows. This paper describes the analysis of a voltage/var control (VVC) structure that includes the cooperative control of the reactive power regulators of...
As the penetration level of embedded generation in the electricity distribution network rises, network operators' need for real time and geographically accurate information about the Low Voltage (LV) network increases. Smart meters and network monitors are the main providers of Smart data to the network operators. However, the Smart data need to be presented to the users in meaningful ways, that are...
Demand aggregators are new market players that represent a group of consumers in the electricity market. This paper proposes an aggregator model responsible for gathering residential and commercial consumers, which has the role of managing their flexible consumption in the day-ahead electricity market. A methodology to optimize the aggregator's bids is also presented. It optimizes the scheduling of...
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