Location: Djerdap, Serbia
End-user: JP EPS, Serbia
Fluids: Water
Start-up date: 2022
Djerdap 1, located in the Iron Gate gorge on the Serbian side of the Danube River, is one of the largest hydropower plants (HPP) in Europe with a capacity of 1,058 MW. State-owned utility company Elektroprivreda Srbije (EPS), who runs the industrial complex, is not only responsible for electricity generation but also for operation and maintenance of the ship lock used to transit vessels through the Djerdap 1 dam. The dam has a navigation lock with three rectangular chambers to bypass it. The lock length is 620 m / 2034 ft.
To increase navigation lock efficiency, minimize long closures and vessel waiting times as well as strengthen the overall reliability and competitiveness of the waterway, the utility company started an overhaul of the lock. The whole project, co-financed by the European Union (EU), was contracted to an EPC. One part of this complex project involved modernizing the instrumentation for water level control.
Efficient and safe lock control requires the water levels upstream and downstream of the lock as well as in the lock chambers to be measured. The shock pressure of water on the gates can be prevented if the lock gates are moved only when water levels on both sides of the gates are roughly balanced, with a defined tolerance of 30 mm / 1.18 inch. Reliable level measurement is key to enabling automation of the process. The lock chamber water levels serve as control variables for smooth lock control and ship transit. The water level in the lock chambers can vary from 7…21 m / 23…68.9 ft.
Next to a submersible level probe, the operator decided to also install an alternative level technology in each chamber. The gates of the chambers only open when the different level measurements in the chambers are within a tolerable deviation of 30 mm / 1.18 inch.
OPTIFLEX 2200 F
WIG D.O.O., integrated each level transmitter into the control system of the operator.
Signals from the level transmitters and probes are connected to the corresponding redundant PLCs, i.e. to the redundant distributed I/O units of the electro-hydraulic drives at the upper, middle and lower head.
WIG covered the complete scope of supply – from technical advice to delivery and integration into the customer’s PLC environment to commissioning and after sales service.
The TDR guided radar level transmitter helped the operator improve lock efficiency significantly, reducing ship transit time by almost half an hour. This in turn increased the overall competitiveness of the waterway. Long closures due to inadequate control variables and lack of automation are a thing of the past.
