Discharge measurement at the hydro powerplant intake

Task

The river Alfenz is the water supply for the same-named small hydro power plant. Over the seasons but also during a day the river carries changing water amounts. To ensure a regular operation of the power station as well as a sufficient level of residual water a water reservoir was built at the intake of the hydro power station. Here the intake and outlet of the water is regulated. The regulation of the intake gate should be adapted to the current water amount and ensure sufficient amount of residual water in the water supply.

Solution

To determine the water amount at the intake gate to the water reservoir, water level and velocity of the water is measured at the outlet for the fish pass. The measuring system delivers over a converter the signals water level, velocity and discharge to the process controlling technics. This regulates then the opening of the intake gate. A year-round, continuous measurement with very low maintenance requirements is advantageous with the non-contact radar measurement technique and the integration in the process controlling technics.

Implementation

The needed measurement data are gathered with no contact to the water and continuously with the help of SOMMER radar sensors (RQ-30, RG-30). Over the process controlling technics the intake gate can be set in accordance with the compulsory residual water amount. Therefore the power plant operation is optimized. Control measurements are done to validate the parameterisation of the sensors and the discharge amount. Here for example the tracer dilution method with TQ-tracer system is used. Measurement reports and continuous data collection is relevant for giving evidence to the authorities.   

Further impressions