Analysis of electric vehicle charging stations impact on power quality aspects in low voltage distribution networks

Pojava sve većeg broja proizvodnih jedinica na strani krajnjeg korisnika, te ubrzana integracija električnih automobila, uzrok su velikog broja izazova pred kojima se našla današnja energetika. Opsežne promjene koje zahvaćaju današnji elektroenergetski sustav, a naročito distribucijsku mrežu, aktualizirali su pitanja i potaknuli brojna istraživanja u području kvalitete električne energije. U radu je opisan teorijski koncept izrade programskog modela za obradu i analizu niskonaponskih distribucijskih mreža. Pomoću razvijenog modela, istražen je utjecaj punionica električnih automobila na parametre kvalitete električne energije, s posebnim naglaskom na analizu naponskih prilika i pojavu viših harmonika. Na djelu stvarne distribucijske mreže Republike Hrvatske, simulirani su tokovi snaga i praćene vrijednosti naponskih harmoničkih izobličenja (THD) u ovisnosti o broju instaliranih električnih punionica. Sve su analize provedene za nekoliko scenarija, a korištene su i različite vrijednosti snaga punjenja definirane kao rezultat Monte Carlo simulacija. Rezultati provedenih simulacija, odnosno vrijednosti promatranih veličina (THD i iznosi napona) uspoređeni su sa zahtjevima propisanim normom EN 50 160, te zahtjevima definiranim Mrežnim pravilima elektroenergetskog sustava.The emergence of an increasing number of production units on the side of the end user, and the accelerated integration of electric cars, are the cause of a large number of challenges facing today's energy. Extensive changes affecting today's electricity system, and in particular the distribution network, have brought issues to the fore and spurred numerous researches in the field of Power Quality. The paper describes the theoretical concept of creating a software model for processing and analysis of low voltage distribution networks. Using the developed model, the influence of electric car charging stations on electricity quality parameters was investigated, with special emphasis on the analysis of voltage conditions and the appearance of higher harmonics. In the part of the actual distribution network of the Republic of Croatia, power flows and monitored values of voltage harmonic distortion (THD) were simulated depending on the number of installed electric charging stations. All analyzes were performed for several scenarios, and different values of charge power defined as a result of Monte Carlo simulations were used. The results of the performed simulations, ie the values of the observed quantities (THD and voltage amounts) were compared with the requirements prescribed by the EN 50 160 standard, and the requirements defined by the Grid Code of the power system