Many gas turbines use variable inlet guide vanes (VIGV) to control the compressor airflow and prevent surge.
The control of some types of VIGV system is hydro-mechanical and is prone to wear and drift. Changes in the scheduling of the VIGV’s can not only cause a drop in engine efficiency but can also lead to compressor stall/surge and consequently catastrophic failures of blading. Monitoring the positioning of the VIGV’s is therefore essential for long-term reliability and maintenance.
TCL have developed a transducer that monitors the angular position of the VIGV’s of a turbine and converts this into an electrical signal that can be used as an input to a SCADA system or chart recorder. The device was specifically
developed for the Rolls Royce Avon gas generator but can be modified to fit most gas turbines.
Monitoring of the VIGV position is essential for long term reliability and maintenance. The variable inlet guide vane position transducer comprises a transducer and mounting plate for fitting onto the inlet guide vane.
This allows feedback to the turbine control system from the movement of the guide vane.
The Rotary Position sensor used within this assembly uses high performance conductive polymer tracks and contact designs to increase linearity response and lifetime. The output is a standard 3-wire 5K potentiometer which can be used in control systems by itself (voltage divider) or with a panel mount signal conditioner option provided by TCL to convert the signal to industry standard 4-20m A signal.
The signal conditioner produces a 4-20 mA signal proportional to guide vane angle which can be wired as an input to the existing
control system:
| Rotary Position Sensor |
| Insulation Resistance |
1000M Min 500V DC |
| Maximum Voltage |
13.5V DC |
| Rotation Life (-40o - 130 o) |
5,000,000 Full Cycles |
| Functional Temperature Range |
-40°C | 155°C |
| Mechanical Shock (Handling) |
1m Drop onto Concrete Floor |
| Mechanical Shock (Bump) |
1000 40g 11 ms Shocks (3 axis) |
| Vibration (Sinusoidal) |
10 – 57 Hz @ 1 mm Displacement |
| 57 – 100 Hz @ 10 g |
| 100 – 500 Hz @ 27 g |
| Humidity |
40°C 96% RH 504 Hours |