SsangYong Actyon Sports II. Manual — part 59

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0000-00

(10) E-VGT control

A. Overview

E-VGT (Electric-Variable Geometry Turbine) turbocharger system in D20DTF engine uses the venturi

effect that controls the flow rate of exhaust gas by adjusting the passage in turbine housing. The newly

adopted DC motor actuator (E-actuator) controls the E-VGT system more precisely and faster. To get

the high operating power from turbine, the ECU reduces the exhaust gas passage In low speed range

and increases it in high speed range.

B. Components

HFM (intake air

temperature)

Front EGT sensor

E-VGT actuator

Accelerator pedal

module

Crankshaft

position sensor

Oxygen sensor

T-MAP sensor

Coolant

temperature

sensor

D20DTR ECU

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C. Input/Output for E-VGT system

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D. E-VGT system control

Turbocharger system operates the E-VGT actuator according to the signals for engine epm, accelerator

pedal position, atmospheric pressure, T-MAP, coolant temperature and intake air temperature.

Turbocharger actuator is performed PWM control by ECU.

In general, the boost pressure feedbacks the turbocharger operation and the boost temperature is used

for calculating the precise density.

E-VGT provides higher engine power with faster reaction speed compared to conventional VGT.

Operating wave

Vane

Control

Low

speed

range

In low speed range:
retract the vane to
increase boost
pressure. The vane
has low (-) duty, and
the unison ring
moves to retract the
vane in weak PWM
signal.

High

speed

range

The unison ring
moves to extend the
vane in strong PWM
signal. Maximum
pressure is 3 bar and
the system controls it
according to the input
signals.

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HFM (intake air

temperature)

CDPF

Electric throttle

body

Coolant

temperature

sensor

Oxygen sensor

Injector (C3I)

E-EGR valve

(11) Wide band oxygen sensor control

A. Overview

For diesel engine, combustion is not performed at the optimum (theoretically correct) air-fuel ratio and

the oxygen concentration is thin in most cases. So the wide-band oxygen sensor is used for this kind of

engine, and this sensor is a little different from the one that used for gasoline engine. The combustion in

diesel engine is controlled by fuel injection volume. Therefore, the wide band oxygen sensor should be

used in diesel engine. This sensor measures the air-fuel ratio in very wide range, and is also called full

range oxygen sensor.

The wide band oxygen sensor measures the oxygen density in exhaust gas and sends it to ECU to

control the EGR more precisely.

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B. Components

D20DTR ECU