IEEE Electrification - March 2022 - 70

power, torque, and rotational speeds are
5,000-W, 27 NM, and 5,000 r/min, respectively.
It has a single transmission ratio
from the motor to the wheel of 1:5. Moreover,
the specific energy consumption of
the scooter based on the modeling and
simulation is approximately 25.74 km/
kWh. According to the specific energy, its
battery pack is designed to reach 70-100 km
per charge and have at least 3 kWh.
Additionally, the battery voltage is set at
100 V because it would require 350 A at
3,500 W. Therefore, 100 V is chosen to
minimize the size of the power cable.
The designed electric scooter chassis
is capable of sustaining maximum
dynamic and static loads of 500 and
150 kg, respectively, as shown in Figure
6(a). Based on the finite element
method (FEM) simulation and analysis,
several hardpoint connections must be
reinforced, such as suspension point
connection on the main chassis and its
swingarm and electric motor assembly
points. The electric motor could be
bought directly as a basic design or
developed from scratch. The processes
of the designed electric motor are depicted
in Figure 6(b). The second option was
chosen, where the motor was designed
and developed using the FEM. Figure
6(b) shows that the designed electric
motor could produce a maximum
power of 3,500 W, 27 NM of torque, and
5,000 r/min, respectively. The best traction
motor for the electric scooter is an
axial brushless dc (BLDC) motor. Moreover,
a special cooling system using natural
air cooling was designed. The axial
BLDC motor featured its distinct fin for
maximizing the effect of natural air
convection cooling.
The motor controller and battery pack
were also designed from scratch. The controller
must regulate the electric scooter
power delivery and handle a maximum
current of 350 A and voltage of 130 V. The
controller used modular concepts, where
its parts were split into the controller,
gate driver, and three-phase, 3-kW, highvoltage
inverter modules. Based on the
BLDC motor power requirement, the
electric energy is provided by the battery
pack. Therefore, the battery is designed to
supply electric power. According to the
specific energy consumption, to reach a
70
IEEE Electrification Magazine / MARCH 2022
Basic
Ideation
Engineering
Design
Detailed
Engineering
Design
MVP
Development
and Iterations
Testing
Design
Revisions
Final
Design
* Design
Specifications
* Targeted Price
* Artist Illustration
* Load Calculation
* Power Calculation
* Dimensioning
* Dynamic Simulation
and Modeling
* Chassis Modeling
* Geometry Analysis
* Ergonomy Analysis
* Material Analysis
* Powertrain Design
and Analysis
* Stability Analysis
* Electrical Design
* Instrumentation
Design
* Chassis
* Composite
Body Work
* Electric Motor
* Structural
Integrity
* Accessories
* Braking System
* Suspension System
* Lighting System
* Performance
* Safety
* Endurance
* Reliability
* Extreme
Conditions
* Geometry
* Chassis
* Bodywork
* Electrical
Component
* Mechanical
Component
* Blueprints
* Patents
* Papers
* Prototypes
* BoQ and BoM
Figure 4. R&D (engineering design) processes of the electric scooter; BoQ: bill of quantity; BoM: bill of material.

IEEE Electrification - March 2022

Table of Contents for the Digital Edition of IEEE Electrification - March 2022