arrow_back_ios

Main Menu

See All Acoustic End-of-Line Test Systems See All DAQ and instruments See All Electroacoustics See All Software See All Transducers See All Vibration Testing Equipment See All Academy See All Resource Center See All Applications See All Industries See All Insights See All Services See All Support See All Our Business See All Our History See All Our Sustainability Commitment See All Global Presence
arrow_back_ios

Main Menu

See All Actuators See All Combustion Engines See All Durability See All eDrive See All Production Testing Sensors See All Transmission & Gearboxes See All Turbo Charger See All DAQ Systems See All High Precision and Calibration Systems See All Industrial electronics See All Power Analyser See All S&V Hand-held devices See All S&V Signal conditioner See All Test Solutions See All DAQ Software See All Drivers & API See All nCode - Durability and Fatigue Analysis See All ReliaSoft - Reliability Analysis and Management See All Test Data Management See All Utility See All Vibration Control See All Acoustic See All Current / voltage See All Displacement See All Load Cells See All Pressure See All Strain Gauges See All Torque See All Vibration See All LDS Shaker Systems See All Power Amplifiers See All Vibration Controllers See All Accessories for Vibration Testing Equipment See All Training Courses See All Whitepapers See All Acoustics See All Asset & Process Monitoring See All Custom Sensors See All Data Acquisition & Analysis See All Durability & Fatigue See All Electric Power Testing See All NVH See All Reliability See All Smart Sensors See All Vibration See All Weighing See All Automotive & Ground Transportation See All Calibration See All Installation, Maintenance & Repair See All Support Brüel & Kjær See All Release Notes See All Compliance See All Our People
arrow_back_ios

Main Menu

See All CANHEAD See All GenHS See All LAN-XI See All MGCplus See All Optical Interrogators See All QuantumX See All SomatXR See All Accessories See All Accessories See All BK Connect / Pulse See All API See All Microphone Sets See All Microphone Cartridges See All Acoustic Calibrators See All Special Microphones See All Microphone Pre-amplifiers See All Sound Sources See All Accessories for acoustic transducers See All Experimental testing See All Transducer Manufacturing (OEM) See All Accessories See All Non-rotating (calibration) See All Rotating See All CCLD (IEPE) accelerometers See All Charge Accelerometers See All Impulse hammers / impedance heads See All Cables See All Accessories See All Electroacoustics See All Noise Source Identification See All Environmental Noise See All Sound Power and Sound Pressure See All Noise Certification See All Industrial Process Control See All Structural Health Monitoring See All Electrical Devices Testing See All Electrical Systems Testing See All Grid Testing See All High-Voltage Testing See All Vibration Testing with Electrodynamic Shakers See All Structural Dynamics See All Machine Analysis and Diagnostics See All Calibration Services for Transducers See All Calibration Services for Handheld Instruments See All Calibration Services for Instruments & DAQ See All On-Site Calibration See All Resources See All Software License Management

Iron Gate Dam: Measuring the efficiency of turbine blades

IEENT and MFB, Serbia

Introduction

Improve Efficiency of a Water Power Plant and Help to Grow Green Energy

This story tells us how the efficiency of an existing water power plant increased up to 10%, using modern strain-gauge technology and the PMX measuring system. The Iron Gate I (Djerdap Gorge) Hydroelectric Power Station is the largest dam on the Danube River, and one of the largest hydro power plants in Europe. It is located on the Iron Gate gorge, between Romania and Serbia. The project started in 1964 as a joint-venture between the governments of Romania and Yugoslavia for the construction of a major dam on the Danube River, which would serve both countries. At the time of completion in 1972, it was one of the largest hydroelectric power stations in the world with twelve units generating 2,052 MW, divided equally between the two countries at 1,026 MW each.

chevron_left
chevron_right

Previous mechanization solutions reach their limits

After being in operation for more than 30 years, the revitalization project of six turbines started in Serbia in 2009. The aim was to increase the installed power as well as the efficiency by 10%. The installed turbines on Đerdap1 are old Kaplan turbines with adjustable blades, and the old design needed change and optimization. The target was to determine, through extensive tests of operational states, where the ratio of produced electricity and consumed water was the largest. For this purpose, IEENT (The Institute of Nikola Tesla in Belgrade) in cooperation with MFB (The Faculty of Mechanical Sciences, University of Belgrade) and TRC PRO (Technical Research Center) designed a concept of how to measure the efficiency in real-time under working conditions. To gain the highest effort and increase, the power production of the turbine and the mechanical design of the turbine blades were calculated and designed according to the latest standards.

Reliable sensor technology

The basic tool for the measurement are strain gauges, which are installed directly at the turbine wheel input stage. Strain gauges have the advantage of offering a high long-term stability. This is important in this project because they operate in a virtually endless operation in the plant and it is not efficient to stop the turbine for a recalibration.

  • The first strain gauge measurement performed the torque measurement. 
  • The second strain gauge measurement performed the axial force and speed measurements on the turbine in the input stage.

Strain gauges for torque and axial force measurement were positioned on the shaft between turbine wheel and generator (above the turbine wheel and below the generator). They were placed on four axes (view from above: four points equally spaced on the circumference). For the torque measurement, the engineers decided using the strain gauge type HBK XY41-3/700. Two strain gauge full bridges are working in parallel connection. For the axial force measurement, the engineers chose the strain gauge type XY31-3/350. Four strain gauge full bridges are working here in parallel connection.

INTERNAL USE - Case Study  04_iron-gate_axis1

Axis 1

INTERNAL USE - Case Study  05_iron-gate_axis2

Axis 2

INTERNAL USE - Case Study  06_iron-gate_axis3

Axis 3

INTERNAL USE - Case Study  07_iron-gate_axis4

Axis 4

After the installation of the strain gauges on the shaft, they were given an electrical protection with a special cover. To prevent the strain gauge measurement in this harsh environment from electromagnetic interferences (EMI), a final cover was put on the measurement areas. Because the turbine shaft rotates under working condition, the engineers had to find a safe way to transmit the very tiny signal from the strain gauges to the PMX measurement amplifier system. Additionally, a telemetry system, which sends the measuring signals wirelessly from the rotating shaft to the receiver, was installed.

Process data-acquisition and evaluation

In the requirements, the engineer-team defined an easy-to-use, robust, and powerful DAQ and evaluation software, which has to capture all measurement signals at full speed as well as the calculated channels from the PMX system. These channels are calculated in real time, which means they are calculated with the same speed as the measurement signals. Additionally, the software has to visualize and store all the data and generate a printed report on demand. All data was captured with HBK’s catman data acquisition software:

INTERNAL USE - Case Study  14_iron-gate_catman-screenshot1

Screenshot from HBK catman application for torque and axial force measurement during data acquisition with PMX

INTERNAL USE - Case Study  15_iron-gate_catman-screenshot2

Screenshots from catman application for torque and axial force measurement during data acquisition with PMX

INTERNAL USE - Case Study  16_iron-gate_catman-screenshot3

Recording in HBK catman with startup of the turbine A4: Torque, axial force, rotational speed, and calculated power

After finishing the project on A4, efficiency tests were performed and new turbine characteristics were determined.

Here are once again the highlights of the implemented HBK measurement solution:

  • Fast and easy deployment
  • Easy setup and helpful diagnosis
  • High resolution, accuracy, and speed
  • Calculated channels inside the device:
    • Dynamic signals and filtered signals
    • Torque calculation from strain measurements
    • Force calculation from strain measurements
    • Power calculation from torque and rotational speed measurement
    • Web visualization application development for data storage without a PC and visualization on a PC, tablet, or smartphone (any device with the web browser).

About IEENT (Institute of Nikola Tesla in Belgrade)

Their multidisciplinary team is made up of top experts from various technical and technological sciences, qualified to efficiently and with top quality solve research and development and practical professional and engineering tasks in the areas of strategic studies in the power industry.

 

About MFB (Faculty of Mechanical Sciences, University of Belgrade)

Faculty of Mechanical Engineering is an institution of national importance, basis for the development of mechanical science and industry.

Further Information

The measurement and control system needs to fulfill several tasks, such as fast and reliable measurements, easy set-up, real-time calculations, diagnosis information, no additional software installation, and efficient pricing. These can be archieved with the PMX measurement and control system. In the first step, PMX was used as a four-channel amplifier for voltage inputs. The first input was the voltage from the telemetry system for torque measurements using the strain gauges installed on the turbine. The second input was the telemetry system for axial force measurement in the turbine, and the third input was rotational speed. All signals were sampled with 19.2 kHz, which guarantees a high measurement-bandwidth and evaluation of the measurement signals. All adjustments to the PMX system are handled via the standard Ethernet-interface and the internal PMX web server. This solution offers the benefit of adjustments being done via the machine network or even remotely if the additional Wi-Fi is available. So each engineer had a real-time view of the application and the status of the test. An integrated operator control prevented insecure operation.

In the second step, the desired and relevant information had to be calculated in real time. This can be done with the Smart Functions of PMX, which can be used by the operator very easily without having extensive software skills. They offer several mathematical functions, like a pocket calculator, logical functions, and process evaluations up to controller functions like PID-controller. To calculate the mechanical power, the following formula can be used: 

INTERNAL USE - Case Study  11_iron-gate_Formula

Units: P: W; M: Nm; n: rpm. 

INTERNAL USE - Case Study  12_iron-gate_pmx-screenshot1

PMX webserver overview with measuring signals, calculated signals, and I/O signals.

INTERNAL USE - Case Study  13_iron-gate_pmx-screenshot2_calculated-channels

PMX web server with the power calculations

As an additional protection against dust and EMI, the PMX amplifier was mounted in a cabinet, which includes the supply of the telemetry system also.  The glass in the cabinet allows a direct view onto the PMX and the diagnostic LED indication. This is an easy and quick indication to determine a potential error on the device and the measurement status. This is a big advantage for the service engineers, as they can get quick information without using any additional test equipment. A detailed and deeper diagnostic is stored in the PMX Log-file. This file is stored in the internal memory of the PMX. It covers all upcoming errors of the device and measurement, as well as any changes to the parametrization made by the operators. This allows 100% coverage of the whole test and measurement process.

“A very helpful tool for parameterization, setup and control we found the PMX web server. We didn’t need any additional software and could use the standard web browser on our PC’s tablet or smartphone. And it is permanently available in real-time over the whole power-plant area”, says Hotimir Licen from TRC PRO.

Hotimir Licen from TRC PRO

Technology Used

Related Case Studies