ER22

The switch to electricity had been made the previous year during the ER21 project and the ER22 management saw the potential in continuing on the electric path even though the electric systems were not finished during ER21. It was evident that these systems were challenging to create and integrate into ER21; therefore, much of the ER21 concept was kept completely or as inspiration during the design and production of the ER22 car.

To reach the ER22’s goals of creating a competition-ready electric car, the team held several recruitments at the University, all of which were successful and resulted in the association reaching its highest member count of around 90 people. Even though the team was 90 members strong, the biggest challenge in the project was the lack of members with electrical knowledge, especially regarding high-voltage. This meant that a small number of people had a lot of responsibility and spent long hours designing and building high-voltage electrical systems.

Due to this huge undertaking of crucial members, some of the milestones regarding the high-voltage systems were delayed during production. However, the design milestones were passed and the mechanical production deadlines were met as expected. The ER22 car was thus mechanically finished in March and after a lot of hard work from the Power Electronics team, the first electrical drive was done in June. At the start of August, only 24 hours before departure to the long-awaited competition, ER22 was completely competition-ready.

ER22’s steel frame, steel battery container, and carbon fiber aerodynamic pack passed the scrutineering at the FSEast competition. The car’s battery consists of Sony VTC cells, 144 packs in series with 600 V. The cells weigh around 40 kg and give the car a capacity of 8 kWh. The high-voltage electronic systems passed the first electric scrutineering step at FSEast. The motor in ER22 is an axial flux AC machine from Emrax, which gives the car a peak horsepower of 148.

100

[kW] – POWER

264

[kg] – MASS

8.0

[kWh] – CAPACITY

PICTURES

FEATURES

Motor

EMRAX 228 HV LC, (100kW peak, 42kW continous)

Inverter

UniTek BAMOCAR-PG-D3-700/400

Battery Cells

720 x Sony VTC6 18650 cells
(preassembled as Energus Li1x5pVTC6T)

Battery Configuration and Voltage

144s5p – 600V

Battery Capacity

8.0 kWh

Differential

Drexler FS2016 LSD

Chassis

Tubular steel spaceframe, Docol R8

Body

Carbon fibre panels

Aero

Front Wing, Side Aero, Rear Wing and Diffuser. Cl = – 2.7

Suspension Front

Double unequal length a-arms with pushrods, horizontally oriented Öhlins TTX25 dampers

Suspension Rear

Double unequal length A-arms, push-rod, vertically oriented Öhlins TTX25 dampers

Wheelbase

1585mm

Track Width [F/R]

1200 / 1180 mm

Wheel

13×7.0″ OZ magnesium rims

Tires

Goodyear 20.0 x 7.0-13″

Weight

264 kg

ROLLOUT

DIGITAL REVEAL