Measurements on turbines
Problems: Mechanical damage of the turbine, shaft breakage of the turbine.
Goal: Support for optimal design of turbines, prevention of superposition of torsional oscillations due to frequency fluctuations of the grid.
Turbines for power generation can be gas or steam turbines. The increasing development of turbines goes in the direction of larger and more efficient rotating machines. Due to the enormous mass and speed of rotation during operation, turbines possess enormous energy. Critical torsional vibrations can occur both during planned run-up and run-down of turbines for maintenance (“outage season”) and during continuous operation. They lead to mechanical damage or even shaft breakage and should therefore be avoided as a matter of urgency. Especially grid frequency fluctuations can promote torsional vibrations at the turbine during continuous operation. A torsional vibration analysis makes it possible to avoid critical operating points and to ensure safety. The aim here is to prevent torsional vibration from being superimposed by frequency fluctuations in the grid, feedback effects and the natural frequency of the system.
Speed measurement on turbines is usually carried out with magneto-resistive sensors on gear wheels. Here, one measures quantities such as single-channel measured quantities such as the oscillation angle and uses the characteristic of the angular velocity. Furthermore, it is possible to measure the torsion angle between the beginning and the end of the rotor during operation in order to be able to observe the dynamic torsion. Measurements over a longer period of time allow knowledge to be gained about the endurance running capability under different load conditions. These result from loads from the energy grid.
The recorded measured values are evaluated in the spectral range.
Furthermore ROTEC ENGINEERING provides you with support and technical engineering know-how for problems related to vibration analysis of engines, transmissions and drive trains. With our know-how, we make a valuable contribution to your product in the areas of timing gear validation, valve train optimization, clutch design, transmission errors (TE), transmission optimization, oil supply optimization, powertrain measurement and optimization, current and voltage analysis, and the application of measurement technology.
Frequency spectra spectroshygram
- Series of high-resolution frequency spectra; frequency resolution: 1/40 Hz, 1/100 Hz, …
- Individual speed measuring points (vibration angle and angular acceleration) as well as difference between two speed measuring points (torsion angle, dynamic torsion)
- Also very small vibration angles (< 1/1000 degree) because of the 12.3 GHz counter on the ROTEC speed board
- Identification of resonance points during run-up and spin-out