A VGT or VTA is a turbocharger, wherein movable vanes are replaced by conventional fixed vanes, which can change angles to control the exhaust flow on the turbine blades.
This helps the engine control to balance the volume of air with the fuel along with the entire engine load range.
Working of VTA
The VGT or VTA consists of nozzle rings equipped with adjustable angle-changing vanes. Each vane is connected to control a ring using a lever, which reduces the thermal hysteresis and increases the positional accuracy.
The vane position or the angle is adjusted by the control ring connected to the electric positional motor via a reduction gear. The control system governs the action of the microprocessor-controlled positional motor.
The position or angle of the vanes is thus altered after comparing the feedback signals of – air pressure after the blower, and exhaust gas temperature before and after the turbocharger.
Advantages of VTA
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