ISUZU:Isuzu to release new Elf Diesel Hybrids


	Hot News

	2010

	2009

	2008

	2007

	2006

	2005

	2004

	2003

	2002

	2001

	2000

	1999

	News & Events

	Disclaimer

Outline of hybrid system

1) System structure
An original hybrid system includes a motor / generator, battery, inverter, and Smoother-E automatic shift, based on the 4HL1 diesel engine.

Engine • Four-star rated ultra-low PM emission 4HL1 with DPD.

Battery • Charges off electricity generated by motor / generator via inverter.

Inverter • Converts direct current into alternating current and the reverse, as needed between motor / generator and battery

Smoother E automatic shift • Disconnects power from engine automatically upon deceleration, and charges electricity with high efficiency.

Motor/generator • Motor assist when starting and accelerating. Upon deceleration, generator converts kinetic energy into electricity.

2) System operations

When starting and accelerating, or when the engine is under a heavy load, the vehicle runs on both the engine and electric motor using battery power

Vehicle runs as a fuel-efficient diesel engine during constant-speed runs only. The Smoother-E automatic shift changes speeds automatically for optimum fuel economy.

When decelerating, Smoother-E automatic shift automatically disengages clutch to prevent loss of regenerative energy, charging on battery efficiently.

After stopping, moving the shift lever into the N position will stop the engine automatically. Moving the lever to D restarts the engine. Gas emission is reduced, while fuel economy is improved at the same time.

[ Hybrid system specifications ]

Engine	Engine type	4HL1
	Displacement	4777cc
	Maximum output	95kW (130PS)/3000rpm
	Maximum torque	333Nm (34.0kgm)/1500rpm
	Fuel injection system	Common rail
	Post-processing system	DPD
Hybrid system	Motor/generator	25.5kW
	Battery	346V Lithium-ion battery
	Inverter	PWM inverter

Product features

1) Excellent fuel economy and low CO2 emission
In addition to assisting the engine by adding an electric motor, the Smoother-E automatic shift system allows high-efficiency regenerative energy and automatic shifting in fuel-saving speed ranges. Together with the idling stop-and-start system, these advances deliver world-class(*) fuel economy.
The system achieves fuel economy improvement of 35%(*) in M15 mode, which is generally used for assessment of the fuel efficiency of a hybrid vehicle, and improvement of 10% to 20%(*) in normal city driving.
Thus, the CO2 emissions regarded as a cause of the global-warming are reduced by 25% in M15 mode.

(*)	2- to 3-ton class cab-over type diesel hybrid truck
-	Fuel economy values are in comparison to a conventional diesel truck (4HL1).
-	Figures based on improvements of fuel economy achieved with start and stop traffic (5 to 10 percent in city driving). Improvement of fuel economy is more moderate when idling/stopping is lessened.
-	Fuel economy may not improve on highways or in suburban driving where there is less acceleration / deceleration and idling / stopping.

In the Elf hybrid truck, an automatic shift function disengages the clutch automatically, recovering most of the energy made available by deceleration. As a result, the high assist energy leads to great improvements in fuel economy.

Idling stop and start

When stopped at a traffic light or elsewhere, shifting into N position stops idling and Hill Start Aid (HSA) operates.
When starting, shifting into D or R position will restart the engine. Turning the idling stop switch on or off allows the idling stop function to be canceled.

Idling stop	After stopping, shifting to N position stops engine.
Restart	Upon starting, shifting to D or R position restarts engine.

2) Clean exhaust gas
A hybrid system based on 4HL1 diesel engine is included. Under the 2003 new short-term exhaust emission regulations, particulate matter (PM) is reduced by 85%, and NOx is reduced by 25% or more, winning the certification as an ultra-low PM emission diesel vehicle (85% reduction) and for its low gas emissions, as an "excellent low pollution vehicle". In addition, it has been listed as a "good low-pollution vehicle" under the eight cities low pollution vehicle certification.

[ Exhaust specifications ]

	Elf hybrid	Diesel (4HL1)
NOx (g/kWh)	2.42	3.24
PM (g/kWh)	0.020	0.023
CO (g/kWh)	0.50	0.50
HC (g/kWh)	0.20	0.20

3) Secure hybrid system
Employing long-life and lightweight lithium-ion batteries for the first time in Japan

Lithium-ion batteries with a lifetime approximately 3 times longer than that of nickel metal hydride batteries are used. The resulting lightweight battery is most suitable for light-duty hybrid trucks.

Employing Isuzu's original PTO parallel driving system

A PTO type parallel-drive hybrid system is employed which has the motor/generator installed on a shaft different from that of an engine. Even if a failure occurs in the hybrid system, driving can be continued on just the diesel engine, without interferences to the engine driveline.
Control signals are connected to the vehicle ECU just as in a normal diesel unit. The vehicle remains controllable in case of failure of the HEV ECU due to the parallel layout.

The motor/generator is installed underneath surface of the frame. This structure prevents lifting of the floor of a van container installed on the truck.

4) Low maintenance cost
The Smoother-E automatic shift is standard equipment. This system eliminates any need for clutch adjustment or replacement, dramatically reducing maintenance costs, while preventing failures on the road due to clutch problems.