28 research outputs found
Measurement-based modelling and validation of PV systems
This paper presents the analysis and results of modelling of various photovoltaic (PV) systems. Two general models are discussed and presented: an analytical model and an equivalent circuit model, both formulated for main PV technologies currently available on the market. Analytical model does not require any PV system specific input data or parameter, and is formulated as a generic performance model of a considered PV technology. Equivalent circuit model, however, requires specific input data and adjustment of the model parameters, in order to provide an accurate representation of a modelled PV system. The paper provides direct comparison of models based on manufacturer’s specification data and available measurements, as well as the discussion of obtained results
Handling uncertainties with affine arithmetic and probabilistic OPF for increased utilisation of overhead transmission lines
Voltage dip immunity aspects of power-electronic equipment : recommendations from CIGRE/CIRED/UIE JWG C4.110
This paper presents some of the results from an international working group on voltage-dip immunity. The working group has made a number of recommendations to reduce the adverse impact of voltage dips. Specific recommendations to researchers and manufacturers of powerelectronic equipment are considering all voltage dip characteristics early in the design of equipment; characterize performance of equipment by means of voltage-dip immunity curves; and made equipment with different immunity available
Voltage dip immunity of equipment and installations : messages to stakeholders
This paper presents the messages to the stakeholders on voltage-dip immunity as extracted by UIE WG2 from CIGRE TB412 [1]. The paper summarizes the main recommendations from this technical brochure in the form of messages towards regulators, standard-settingorganizations, network operators, industrial customers, equipment manufacturers, and power quality monitor manufacturers, researchers
Real-time grouped management of Electric Vehicle Battery Chargers (EVBCs) for voltage profile improvement in radial distribution networks
Voltage limit violation is one of the main factors that impact large-scale integration of electric vehicles in distribution networks. In order to improve voltage profiles, active charging management techniques can be deployed in real-time, considering voltage sensitivities of customer buses. The study in this paper investigates a real-time charging management approach for electric vehicles, clustered according to voltage sensitivities among the customer buses, in a local network. Constant power (CP) and constant current (CC) models, representing a range of electric vehicle battery chargers (EVBCs), are used in simulations with high-resolution stochastic EV charging and residential demand profiles. The paper quantifies the performance of the proposed management approach in a local network model based on real data and IEEE European Low Voltage (LV) Test Feeder
Development of Sub-Transmission Network Equivalents and After-Diversity-Demand Values: Case Study of the UK Residential Sector
This paper, which can be divided into two main interrelated studies, firstly describes the generic modelling of a sub-transmission network model to serve as a UK variant of the original IEEE 14-bus test system. The revised model, based on the actual/realistic power components found both in the UK and in European grids, provides an updated and complete technical description, ready for use in a variety of power system studies, in which the 14-bus test system is one of the most commonly used in the literature. Afterwards, this paper categorises the typical demand characteristics of the residential load sector in the UK, by providing a wider range of reference demand values and loading conditions for the planning and modelling studies of distribution networks, dividing them into four generic residential load subsectors. Different ‘after diversity demand’ values are therefore provided per residential load subsector, classes of customers and seasonal variations of annual power consumption
Review of GB Electricity Distribution System’s Electricity Security of Supply, Reliability and Power Quality in Meeting UK Industrial Strategy Requirements
Voltage-dip immunity: statistics and need for further work
Abstract. This paper presents the main results from CIGRE/CIRED/UIE working group JWG C4.110 and an overview of the need for further work identified by this working group. The paper goes into more details of the voltage-dip statistics collected by the working group and on methods to present the results from voltage-dip surveys
A Review of Approaches for the Detection and Treatment of Outliers in Processing Wind Turbine and Wind Farm Measurements
Due to the significant increase of the number of wind-based electricity generation systems, it is important to have accurate information on their operational characteristics, which are typically obtained by processing large amounts of measurements from the individual wind turbines (WTs) and from the whole wind farms (WFs). For further processing of these measurements, it is important to identify and remove bad quality or abnormal data, as otherwise obtained WT and WF models may be biased, or even inaccurate. There are wide ranges of both causes and manifestations of these bad/abnormal data, which are often denoted with the common general term “outlier”. This paper reviews approaches for the detection and treatment of outliers in processing WT and WF measurements, starting from the discussion of the commonly measured parameters, variables and resolutions, as well as the corresponding requirements and recommendations in related standards. Afterwards, characteristics and causes of outliers reported in existing literature are discussed and illustrated, as well as the requirements for the data rejection in related standard. Next, outlier identification methods are reviewed, followed by a review of approaches for testing the success of outlier removal procedures, with a discussion of their potential negative effects and impact on the WT and WF models. Finally, the paper indicates some issues and concerns that could be of interests for the further research on the detection and treatment of outliers in processing WT and WF measurements