North Wales is an area of significant renewable energy resource, including on-shore and off-shore wind as well as hydro generation. The area in and around Snowdonia is particularly noted for its significant potential for small-scale hydro generation. The area is served by a 'rural' distribution network, characterised mainly by low load density with only a few, long 11kV circuits, which are predominately overhead line construction. Traditional reinforcement methods for such a network to create additional capacity for embedded generation is generally not economically efficient and so such areas are prime candidates for the deployment of Active Network Management (ANM) systems. ANM systems are aimed at maximising the utilisation of the existing distribution network capacity based on real-time network measurements allied with generation power flow management.

The primary network constraint in this example is network voltage. It is proposed that an ANM scheme be deployed on this network to actively manage the output of an existing hydro generator in order for it to utilise the additional generation export capability that is present during periods of higher demand. The ANM scheme will use voltage measurements to calculate in real time if the network has extra generation capacity available. This information will then be used to co-ordinate the output of the generator and other controllable devices.

Objectives

The project contains five learning objectives which go beyond the current ‘business as usual’ approach. These include:

• Analogue control interface with the generator for real (and reactive) power

• Principles of access as applied to a ‘constraint’ (as opposed to the principle as applied to a firm/ non-firm connection)

• Communications methods (e.g. GPRS, line-of-sight packet radio, 3G, etc)

• Remote voltage measurement (including remote terminal units & communications interfaces)

• Primary voltage control (e.g. AVC set point or direct tap change control).