VIGV Monitor

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 consequent 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 4-20mA 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
VIGV Monitor
VIGV Schematic
VIGV Mounted
VIGV Feedback Display