Costs of PQ Networks José María Romero Gordon Frankfurt (Germany), 6-9 June 2011

Romero – Spain – RT2b – Costs of PQ networks.  Costs of PQ monitoring networks.  New smart meters.  Legislation and regulation.  Conclusions. Outline

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Fixed vs. mobile monitoring  Fixed = proactive.  Mobile = reactive (complaints). Problems remain hidden.  Mobile  cheaper: Few devices. No need for a central system. No need for communication links.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Costs evaluation  Expressed as a fraction of each device’s price (100%).  Average system consisting of: Central system managing ~800 devices. 1 communication appliance per substation. 4 fixed equipment per substation.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Fixed equipment  Device: 100%  Installation: 25%  Communication: 4% + 6%/year.  Central system: 4% + 2%/year (per device).

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Mobile equipment  Device: 100%  Installation and removal: 15%/site.  Communication: from 0% up to 16% + 24%/year.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Comparison fixed vs. mobile  Assuming each mobile device is connected for one month  fixed equipment ~ 10 x mobile devices.  Fixed monitoring is cheaper than mobile monitoring after 13 years.  Fixed monitoring gives at least 10 times more time-series data.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Comparison (cont.)

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. New approach  Instead of simple transducers supplying data to the SCADA, combined PQ meters could be seamlessly integrated in new substations.  These devices might have several communications ports: Former ports to be accesed by the SCADA for real-time measurements. Extra ports for archived and online PQ data.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. New approach (cont.)  Cost of these devices is similar or even cheaper than common transducers. Thus their cost would be zero from a substation point of view.  Even if communication is counted as an extra cost, in just 2 years fixed monitoring becomes cheaper than mobile.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. New approach (cont.)

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. New smart meters  Most of the information needed to solving out complaints: Sustained overvoltages and undervoltages. Harmonic distortion. Peak power.  Not really EN compliant, but sufficient.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. New smart meters (cont.)  Data handling issues: Central database likely to face scalability problems. Meanwhile, on-demand downloading of events.  Prospects: Smart meters are already made with the same electrical precision than a class A PQ monitor. They lack of processing power. Maybe on-site hardware upgrades could be a cheap and reasonable solution when a class A device is required.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Legislation and regulation  Utilities are facing major contradictions due to several actors.  Some of them are willing to reduce voltage and time tolerances. This approach would imply a great deployment of PQ monitoring networks, even at low voltage.  Unified and rational solution among involved parties is required.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Utilities facing major contradictions  Increase of distributed generation: Higher voltage oscillations. Sustained overvoltages and undervoltages. No way to control it (just on-load tap changers).  Equipment with reducing immunity: Voltage dips and swells. Sustained and transient overvoltages.  Regulators willing to narrow quality bands: Window size. Voltage dips: sharing responsibility curve.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Unified solution required  Increase immunity: Sustained overvoltages. Transient overvoltages. Voltage dips (see CIGRE C4.110 “labels”). Mandatory installation of protective devices:  Sustained overvoltages (see new EN 50550).  Transient overvoltages.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Unified solution (cont.)  Improve network quality: Sharing responsibility curve: Define certain limits and zones of responsibility. However, take into account different network topologies and constructions rules (otherwise good sites will tend to be worse in the future):  Aerial vs. underground.  Voltage level.  Protected species (birds).

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Conclusions  Fixed PQ devices are useful for solving out problems in advance.  Mobile PQ devices are useful for compliance monitoring due to complaints.  LV customers are almost not monitored.  Smart meters are the cheapest and wider method to fulfill PQ standards in LV.  Combined transducers/PQ meters is the cheapest alternative for substations.

Frankfurt (Germany), 6-9 June 2011 Romero – Spain – RT2b – Costs of PQ networks. Conclusions (cont.)  Instead of trying to find a guilty actor (i.e. utilities), an unified solution among many parties must be appointed: Manufacturers: increase immunity against voltage dips and sustained overvoltages. Installations: more protective devices. Regulators: find reasonable KPIs. Utilities: by means of fixed PQ devices, improve voltage dips performance and voltage control.