Objetivo To install and remotely control a cascade system of three low head turbines over a telephone link from a central computer and to provide solutions to problems associated with asynchronous generators - for example self-excitation, power factor correction, and reconnection transients.The hydraulic design of the overall project has proved to be a success. The projections for maximum power output was 2.0 megawatts. This has been exceeded by 5%; the maximum power output at low tide and maximum flow is 2.09 megawatts. This would indicate that the hydraulic design of(i) the intake works(ii) the channels(iii) the forebay areas(iv) the setting of the turbines(vi) the outlet channels from draft tubes(v) the draft tubesare giving optimum results.The overall hydraulic design also allows successful computer control of the turbine cascade. The design of each of the turbine by-pass channels and weirs etc. allow the various control operations to be carried out in a simple and effective way.For example, it is extremely important that flow rejection from each of the turbines is catered for. Flow rejection occurs mainly in two circumstances:(i) Following loss of grid(ii) Turbine trip due to faultIn each of these instances, the flow through the turbines is reduced in eight seconds by the operation of a weight falling to close the guide vanes. In the case of maximum flow for example, 12 m3/s must be diverted from the turbine to the by-pass spillway in eight seconds. There is a also a resulting surge wave, which is approximately 0.5m high, travelling at a celerity of 3.0 m/s. This surge wave must also be catered for.Technical outlook for the project is good. The turbines are performing well with respect to their efficiency at full load and part load.The only remaining major problem is the lack of automatic trash cleaning. A design for automatic screens has been completed.The control system is operating satisfactorily and successfully demonstrates the way in which a cascade can be controlled automatically.Three sites are in cascade on the River Ballisodare, which will be developed as listed below.SITE 1 2 3 (tidal)Nett head (m) 5. 6 5. 4 5. 4-8. 2Flow (m3/sec) 12 12 12Turbine output (kW) 620 554 1016Turbine type Double reg. bevel gear bulb at each siteGenerator type Induction Induction InductionGenerator output (kW) 590 525 965Voltage (V) 660 660 660The opportunity to operate the stations unmanned (at significant cost savings) arises from the adoption of a fully automated system, both controlled and supervised remotely. The stations at Ballisodare are to be operated from Carlow, using equipment interfaced to each end of a dedicated telephone link.The use of microprocessor based data acquisition and processing systems allows the continuous monitoring and control of the three separate units whose hydraulic and electrical characteristics differ. Programa(s) ENG-ENALT 2C - Programme (EEC) of demonstration projects relating to the exploitation of alternative energy sources and to energy saving and the substitution of hydrocarbons, 1983-1985 Tema(s) Data not available Convocatoria de propuestas Data not available Régimen de financiación DEM - Demonstration contracts Coordinador BALLISODARE ELECTRIC CO LTD Aportación de la UE Sin datos Dirección SHREWSBURY LAWN 100 CABINTEELY 18 Dublin Irlanda Ver en el mapa Coste total Sin datos