Smart Grids

1. Define shortly the following terms or concepts

a) DMS (Distribution management system) [pag 154]
It is a collection of Applications used by the Distribution Network Operators (DNO) to monitor, control and optimize the performance of the distribution system and is an attempt to manage its complexity. The ultimate goal of a DMS is to enable a smart, self-healing distribution system and toprovide improvements in: supply reliability and quality, efficiency and effectiveness of system operation. A DMS should lead to better asset management, the provision of new services and greater customer satisfaction.

b) Microgrid [pag 180]
A smart grid is a distribution system with DG units, energy storages and controllable loads. These active resources are controlled with ICT systems tooptimize energy generation, transmission and distribution.
• A microgrid is a segment of a smart grid, with intended island operation capability. Microgrid should achieve the island operation mode with little or no voltage disturbances to the microgrid loads.
• Microgrid is a single self-controlled entity, that has neutral or positive effect on the distribution system. Power flow from or to the maingrid can be controlled.
. Microgrid is usually a single low voltage network, but can be a building network or a MV voltage network, or part of it.
Can be defined as a low voltage electrical network of small modular distributed generating units (whose prime movers may be photovoltaics, fuel cells, micro turbines or small wind generators), energy storage devices and controllable loads. Theintegration of DMS and MicroGrids can be implemented through setting up the links between the DMS and the MicroGrid Central Controllers (MGCC).

c) LVDC microgrid [diapositiva 107] [online]
Low voltage Direct Current) LVDC microgrid is system where alternative current (AC) is rectified to direct current (DC) and then distributed as DC and finally converted back to AC near the consumption
Possibilityto guarantee high power quality to all customers. Transporting the electricity in DC to not have to convert it afterwards..


d) Interactive customer gateway [online]
Interactive customer gateway (INCA). Is a logical interface integrated with supplying distribution system. It composes of active load appliances, building automation, active network components (utility and customer networks),widespread communications network, local control system, and information systems of external service providers.

e) DR (Demand Response) [pag 113]
Mechanisms to manage the demand in response to supply conditions. Demand response is shifting the loads from peak times to off-peak periods. This flatten the shape of load curve. Demand response flattens load curve by shifting some part of loading frompeak power period to other time period. The target of demand response and load management is to reduce or shift demand from on-peak to off-peak times
f) Virtual Power Plant (VPP) [pag 27]
To aggregate many small generators into blocks that can be controlled by the system operator and then their energy output is traded.

g) Day-ahead (spot) market
The day-ahead market is an auction whereprices and quantities for energy are established for each hour of the subsequent day. In this market, suppliers submit offers to supply energy at certain prices and consumers bid to purchase amounts of energy depending what the price is. As in the spot market, these offers and bids are stacked up to determine the final day-ahead price.
h) Point tariff [diapositiva 52]
(related with electricitydistribution) Dependent on voltage level, not on distance.
• Customer can use the whole national power grid from his connection point
• Network tariff is not allowed to be dependent on customer location in the network
i) Time–of-use pricing [pag 117]
ToU (time of use) rates use different unit prices for different time blocks, usually pre-defined for a 24-hour day. ToU rates reflect the cost of...