Carmen Stanescu

Syncretic Use of Smart Meters for Power Quality Monitoring in Emerging Networks

Operation of distribution networks undergoes dramatic changes in the era of smart grid deployment, due to the higher penetration of distributed generation (usually from intermittent resources), to an ever-increased share of power electronics mediated energy transfer, but also thanks to advancements in instrumentation including smart meters (SMs). In this context, alternative power quality (PQ) monitoring and control, based on a lightweight assessment of voltage parameters to be implemented in new SM would allow optimal real-time network operation and market-correlated services. To this, the authors propose a signal analysis framework for simplified PQ informative assessment method using the so-called instrumentation values available in most of todays SM. It is highlighted that the voltage characteristics made available with high reporting rates can be efficiently used in deriving information on quality of the electricity supplied by public electricity networks. Further applications like smart grid synchro-SCADA observability and voltage control are also addressed in a novel design of SM, with negligible impact on cost.

Power quality assessment in LV networks using new smart meters design

This paper addresses the issue of power quality management in smart grids. Present development of smart grid technologies such as smart metering are continuously generating novel opportunities and breakthroughs for improving the distribution system performance. This paper proposes a novel approach to be implemented in the new generation of smart meters. This alternative method for harmonics and voltage level analysis dramatically reduces the computational power, in order to allow the inclusion of such functionalities in new Smart Meters design. The developed algorithm is detailed and some results are presented. This solution provides an easy access to the power quality issues at customer level, being an important improvement when prosumers are also considered. Unbundled Smart Meter design is also analysed as an appropriate solution for implementing complex PQ assessments.

The management of Power quality, Energy efficiency and the performance of the companies

The paper presents a relationship among three important concepts: Power quality, Energy efficiency and Performance of the company operating in energy field. In most of cases, the improvement of Power quality determines an increase of the Energy efficiency and, of course, the increasing of the performance of the company. The balancing between two of them, could give us the optimum solution to act in the strategic plan, which will be implemented. Some ideas for meeting of the scope of each company operating in the energy sector, increasing the performance of the company, are presented in this paper.

Performance of services achieved by transmission and distribution system operators in Romanian power grid

The paper presents an analysis of the performance of transmission system and distribution services in Romania, in accordance with the Romanian Energy Regulation Authority. The paper lists the targets of the new technical regulations, to ensure proper operation of the users connected to the same network node and compliance with power quality indicators by limitation the flicker effect, reduction of harmonic operating regime and maintaining inside approved limits for the asymmetry. The final part of the paper contains the authors conclusions on issues addressed in it.

Results of power quality monitoring in Romanian transmission and distribution system operators

Two types of Power Quality Monitoring Systems (PQMSs) - one for TSO and other for DSOs, in accordance with Performance standards and Technical Codes of the Romanian Energy Regulation Authority - ANRE were published. The connection to the grid of the renewable sources could determine the increasing of the emissivity of perturbations and the necessity of the propagation study in order to determine the level of the perturbation to the superior level of the voltage of network. The concept “One system for all PQ data” is a new direction used by TSO and DSOs for increasing the efficiency of the PQMS. The results of the monitoring using PQMS for a long period of time, in this paper, validated the expectations from the feasibility study in the design stage of PQMS and allowed the authors to look at some improvement directions of the system. The integration of PQMS with other systems - DMS, SCADA, DFR has been already solved in DSO and a higher efficiency has been achieved. The whole measurement chain in power distribution and transmission activities has been taken into consideration and the results have a good accuracy. Few recommendations are included in the paper. The final part of the paper contains the authors conclusions on issues addressed in it.

Power quality monitoring systems in Romanian electricity market

This paper presents the results obtained with the first and second power quality permanent monitoring systems, installed at the points of common coupling, between transmission system operator and supply operator, transmission operator and eligible customers. The information managed by these systems is received monthly, as statistical reports, by the National Dispatch Center and is included in the reports sent to Romanian Electricity Regulatory Authority. The information gathered in these surveys helps to develop the Romanian PQ regulation, to verify the contract requirements, to report the network performance indices and to identify the network optimization solutions, technical energy losses reduction and customer satisfaction.

Power quality in romanian electricity market

Transelectrica is the Romanian Transmission System Operator and the Meter Operator of the Wholesale Electricity Market (WEM). Some of its partners are Electrica and the eligible consumers. Maintaining the Power Quality (PQ) indices within admissible limits, in the common coupling points (CCPs), is one of the most important of the WEM actors. This paper addresses the salients results of the the first PQ permanent monitoring system, on the Romania WEM. The first part of the paper refers to the PQ standards, and also to the technical and commercial regulations issued by the Romanian Regulatory Authority. They are presented according to the principals objectives of the WEM and taking into account that PQ indices could be part of contractual requirements and must be monitored. The second part presents the main features, functions and equipments of the first PQ permanent monitoring system, which has been implemented in Transelectrica Sibiu Subsidiary, in the HOkV CCPs, at the interface between the transmission and distribution system. The system consists of seven panel PQ meters and one central station. The records have been collected on-line via optical fibber. In the paper there are also presented the methods, the measurements, the first measuring year records and the reports for the national dispatcher centres. This system was located in WEB presentation with geographical map and energytransfer boundary on the WEM.The third part presents the main features, functions and equipments of the Romanian WEM future PQ permanent monitoring system. This one will be implemented during this year, in Transelectrica OMEPA Subsidiary, in the 220 kV CCPs, at the interface between the transmission and eligible consumers. The system will consists of 15 panel PQ meters and one central station. The contract for this project are in progress. The main goal of this system is to assist the dispatcher in taking the necessary measures for a proper correspondence with PQ indices admission limits. The final part contains conclusions and recommendations for future development.

Energy awareness, an important goal for empowering the end customer

Sustainable use of energy through an increased public and individual awareness is an important goal from several perspectives: it is a useful mean to obtain energy savings based on users behavior change, it is a way to understand the local and general context of energy ecosystem related to renewable energy contribution and to carbon footprint and its possible correlation with ambient factors. Thus it helps the citizens in being more responsible towards energy consumption by improving their knowledge and capabilities to take meaningful decisions related to energy aspects. Moreover, awareness on power quality such as supporting the end-user with analysis regarding the voltage level of power grid can also become an effective way of understanding network problems versus user appliances behavior on various voltage patterns. Our approach addresses energy data acquisition based on smart meters, to support energy awareness applications. In this paper we study aspects regarding awareness of energy production versus consumption, that enable a “follow renewables” consumption behavior, as well as awareness on power quality of delivered energy. The overall approach aims to empower customers to positively manage their energy consumption, in line with the European Union Energy Strategy that promotes energy markets with the customer having a central role.

The connection of renewable sources to the grid. Influences and power quality issues

This paper presents results of power quality monitoring collected from transmission system operator (TSO) and several distribution system operators (DSOs) from Romania. The power quality monitoring system is realized in accordance with actual technologies, economic criteria, performance standards and technical codes issued by the Romanian Energy Regulation Authority (ANRE). The implementation of power quality policies in Romania based on the monitoring and corrective actions determined the improvement of quality of transmission and distribution services in power system. The challenges represented by the connection to the grid of new renewable sources have determined ANRE to issue dedicated regulations. The use of the power quality monitoring systems at the interface between TSO and DSO (Distribution Management System, Fault Recording System, Outage Management System) provides better solutions and leads toan increase in the quality of services. The influence of the short-circuit in the propagation of perturbation in power system represents a challenge within the existing context when many renewable sources are connected to the grid.

Meter accuracy in renewable energy sources-based prosumer nodes

The paper presents the energy exchange mediated by a prosumer, highlighting the measurement context for the active power and energy. It is a case study on the combined measurement uncertainty calculated for typical power system measurement chain deployed for hourly power dispatch on the Romanian Energy Market.