Peteris Apse-Apsitis

A Different Approach to Electrical Energy Consumption Monitoring

A different approach to electrical energy/power calculation by means of summing of non-even time current samples over short time periods are described in to the article.

Towards smart street LED lighting systems and preliminary energy saving results

The article gives an overview of various researches dealing with smart or intelligent street lighting systems, and what is meant with this term in different countries. Several available architectures of smart street lighting systems as well as those for future are described and discussed. Further some researches and developments of such systems in Riga Technical University are explained with the examples, also showing preliminary practical energy saving results of tests in real conditions of Riga city infrastructure. This is the first part of articles series about this research.

Practically oriented e-learning workshop for knowledge improvement in engineering education computer control of electrical technology

Creation of good knowledge is based on practical exercise combined with theory learning. Studies in electrical engineering require many different laboratory exercises, traditionally carried out within the premises of university, where students can practice only several hours per week or even less. Such limited possibilities stipulate longer course durations and reduce knowledge creation quality. Possibility to gain some practical skills before carrying out laboratory assignments in real laboratory can become an essential part of the studies., facilitating much deeper understanding of the subject. For this reason a web-based e-Learning distance workshop in electrical engineering is elaborated and discussed in this paper. It is planned to cover courses in electrical drives, power electronics, LED lightning and automatic control.

Virtual energy simulation of induction traction drive test bench

This paper describes a stationary bench simulating the traction drive of electric transport vehicles in traction, freewheeling and braking modes which is planned to investigate the drive operation with and without a supercapacitor energy storage system. The bench contains two equal coupled AC motors simulating the traction drive of surface electric transport and the traction drive load. Before the physical realization of the bench it is necessary to design its virtual model for simulations in order to make sure that it functions as needed. The simulation of the drive operation modes is performed using Matlab/Simulink software.

Development of Energy Monitoring System for SmartGrid Consumer Application

The number of electricity consuming equipment for existing household end-user is continuing to increase, and some residential buildings already consume more energy than existing building regulations prescribe. The uprising SmartGrid technology with alternative energy sources could be a key to solve this problem, but it is demanding also for a “smarter” consumer with ability to monitor and manage his loads. Such a monitoring system can also improve energy efficiency, as it can change consumer non-saving habits, by teaching him possibilities where the energy can be saved. Therefore the paper is devoted to development of new concept of household energy consumption monitoring system. Due to new approach of energy monitoring, the costs of needed metering equipment and total metering system are lowered. The proposed method provides energy consumption apportionment between consumers instead of precise energy consumption metering for each consumer type.

Power Measurement and Data Logger with High-Resolution for Industrial DC-Grid Application

Abstract Power and energy measurement and monitoring is a key factor for many industries in terms of energy and cost efficiency evaluation. Due to trends of Smart Grid concept application in industrial environment, including decentralized DC-Grid implementation, for precise evaluation – faster and low-cost measurement equipment is needed. Manufacturing industry widely uses industrial robots that have dynamic load characteristics for which faster measurement equipment is needed. This paper gives a brief description of the developed power measurement equipment, its structure and interconnection with industrial Profinet network. Further as a testing method steady state and dynamic loads are selected and analyzed. For testing, specially created industrial DC-Grid testing environment and equipment was used. Testing results show that the selected method and idea is working and is able to measure dynamic loads with high resolution. For other industrial load types there is a discussion going on about the issue of how detailed the resolution is needed in industrial SmartGrids, as energy forecast is a new trend in robotic industry and manufacturing planning.

Simulation of Induction Traction Drive with Supercapacitor Energy Storage System Test Bench

Abstract The paper describes the application of supercapacitor energy storage system for induction traction drive test bench that replaces a real electric public transport for performing testing and researches. The suitability and usage of such bench for research purposes is explained and the importance of the development of software mathematical model for performing simulations to be done before physical implementation measures is reasoned. The working principle of the bench and applied components are described. A virtual model of the bench was built and simulations were performed using Matlab/Simulink software. The basic topology of the virtual bench model is described as well. The calculations of this work show the scaling of supercapacitor energy storage system by setting different limits of working voltage range in order to adjust them to test bench parameters, whereas the modelling compares two simulation cases – the application of less supercapacitors and the application of more supercapacitors with the same common rated voltage. The autonomous mode simulations were also performed. Simulation results are analyzed and recommendations for the application of the supercapacitor energy storage system, with respect to initial supercapacitor circuit voltage, are given.