E-Vgt (Electric-Variable Geometry Turbine) System Description - SSANGYONG Actyon Sports II 2012.01 Manual

1. SYSTEM DESCRIPTION OF E-VGT
(Electric-Variable Geometry Turbine)
1) Overview
The E-VGT turbocharger has one shaft where at each ends are installed with two turbines having
different angles to connect one end of housing to the intake manifold and the other end to the
exhaust manifold. As the turbine, at exhaust end, is rotated by exhaust gas pressure the impeller,
at intake end, gets rotated to send air around center of the impeller, being circumferentially
accelerated by the centrifugal force, into the diffuser. The air, which has been introduced to the
diffuser having a passage with big surface, transforms its speed energy into the pressure energy
while being supplied to the cylinder improving the volume efficiency. Also, the exhaust efficiency
improves as the exhaust turbine rotates. The turbocharger is often referred to as the exhaust
turbine turbocharger.
Diffuser: With the meaning of spreading out it is a device that transforms fluid's speed energy into
the pressure energy by enlarging the fluid's passage to slow down the flow.
The E-VGT system installed to the D20DTR engine variably controls the passages of the turbine
housing to regulate the flow rate of the exhaust gas. The actuator of E-VGT is a DC motor
actuator (E-Actuator) which controls more quickly and precisely than the previous vacuum type
actuator.
The engine ECU controls the E-Actuator electronically as follows:
- At low speed: Narrows the flow passage for the exhaust gas, resulting in increasing the
flow speed of the exhaust gas and running the turbine quickly and powerfully.
- At high speed: Expands the flow passage for the exhaust gas, resulting in increasing the
mass flow of the exhaust gas and running the turbine more powerfully.
06-17
1914-01