Building permanent PQ monitoring system on MV network in Elektra Zagreb, Croatia

Necessity for power quality monitoring emerges from rules on deregulated market, legislation according to it, standardization and quality control of delivered merchandise (electrical energy) to the customer, as well as a control mechanism for customers´ installations effect on public distribution networks. On today´s market of power quality measuring devices there is a lot of quality hardware, but its purpose or the systematic approach to its use is always left to the buyer. In most cases buyer of such devices is left with no suggestions or proper technical backup information form the seller that should help him establish a power quality monitoring system. The biggest problem in establishing suitable permanent power quality monitoring system is the funds available for it. In this paper, based on experience in Croatian electrical utility company DP elektra Zagreb, are given some suggestions on how to get as much useful data about state of power quality in medium voltage distribution network at minimum cost, i.e. how to distribute available equipment in order to cover most of the distribution network and so get enough useful information about systems performance considering delivery of quality electrical energy to the customers. Some ideas on what is the purpose of such system, what should be its results and how should they be managed are also given.