Zytek Q10 Hybrid SystemInstalled in a 09HS chassis

In 2009 Zytek became the first manufacturer to score a podium with a hybrid LMP. The car, run by Corsa Motorsports, finished on the podium on its debut at Lime Rock and continued to put in impressive performances throughout the season, culminating in a battle for the overall lead in the season finale at Laguna-Seca.

The Zytek Q10 Hybrid is a non-invasive parallel hybrid system, consisting of a motor-generator, battery and inverter. Its purpose is to recover energy normally wasted during deceleration and subsequently use this energy to assist the internal combustion engine during acceleration.

Whilst assisting, the motor-generator can be used to provide supplementary power or to reduce the power required from the internal combustion engine, in order to save fuel.

It is important to note that the hybrid system itself doesn’t necessarily save fuel, it is by reducing the power output of the internal combustion engine that fuel is saved. The hybrid system can then be used to correct the deficit, facilitating the same power output whilst using less fuel.

Although considered as a single integrated powertrain (figure 1), the two complementary systems can work independently of each other, allowing the 09HS to run as a standard petrol car, a pure EV or a hybrid.

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Fig.1

The electric motor-generator is housed in a bespoke bell housing, designed and machined in house at Zytek. You can see it sits neatly above the input shaft.

The motor-generator itself is not directly linked to the input shaft but is separated by a geartrain and clutch, thus creating a non-invasive system. This enables the system to be deactivated during a race if necessary, allowing the car to continue in standard specification.

The bell housing sits between the engine and the gearbox, as shown in figure 3.

Figure 4 shows the 30Nm motor-generator used in the Q10 system. In accordance with the regulations put forward by the ACO for 2009, all parts used in the Q10 hybrid system are derived from road car technology. This resulted in the motor-generator weighing in at 12kg, a number which will be dramatically reduced in the pure racing ZPH hybrid system, scheduled to debut in 2011.

Under deceleration, kinetic energy that would otherwise be lost as heat in the brakes is converted to electrical energy by the motor-generator. This electrical energy is then converted to chemical energy and stored in the battery (Fig.5).

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Fig.4Fig. 3

Fig. 5

When the hybrid then assists, the chemical energy stored in the battery is converted to electrical energy used to power the motor-generator.

The addition of a 23kg road-derived battery in the cockpit, next to the driver, required a further crash test for the chassis, ensuring that the unit is safely secured in the event of an impact.

During both charging and assisting the 3 phase alternating current at the motor-generator must be converted to direct current at the battery and vice versa, this is performed by the high voltage inverter.

The Q10 inverter is water cooled and temperature sensitive, with an optimum operating range of 40˚-45˚C, well below that of most parts designed purely for racing. This cooling issue was solved by reducing the volume of the left hand radiator and fitting a supplementary radiator in the space created solely to cool the inverter. This was only made possible through reducing frictional losses on the Zytek ZJ458 internal combustion engine, thus enabling it to run at its optimum temperature with less cooling.

Figure 7 shows the layout of the hybrid system within the 09HS chassis; note the twin radiators on the left side of the chassis next to the inverter.

Fig.7

The Q10 project was a successful development platform for hybrid powertrains in motorsport, proving what could be achieved with road-relevant technology.

The next generation Zytek ZPH Hybrid will take the lessons learnt from Q10 but will use bespoke parts designed specifically for motor racing applications. It will provide an “off-the-shelf” hybrid system which can be fitted to a wide number of platforms.

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