Installation Design and Efficiency Evaluation of an EV Transform Powertrain and a 3.3 kW Multi-Charging System Driven by a 30 kW Permanent-Magnet Synchronous Motor

Abstract

This study focuses on the transformation of Jaguar XJ40 vehicles to electric power, with the main equipment being a permanent-magnet synchronous motor (PMSM), lithium iron phosphate (LFP) batteries, an on-board charger (OBC) system, and a battery management system (BMS). The process involves integrating the PMSM with the vehicle’s existing transmission system. This research compares the driving range of battery electric vehicles (BEVs) using different testing methods under the same conditions: simulation, dynamometer (dino), and actual on-road testing. Based on Raminthra’s public roads (RITA drive cycle), one drive cycle covers 7.64 km in 11.25 min. The simulation test by MATLAB/SIMULINK R2016a predicts a driving distance of up to 282.14 km. The dino test, using a chassis dynamometer to simulate driving conditions while the vehicle remains stationary, indicates a driving distance of 264.68 km. In contrast, actual on-road tests show a driving distance of 259.09 km, accounting for real-world driving conditions, including variations in speed, road types, weather, and traffic. The motor achieves 95% efficiency at 2400 rpm and 420 Nm torque. The simulated distance differs from the actual road distance by approximately 8.17%, suggesting reasonable accuracy of the model.

1. Introduction

Climate change due to CO₂ emissions has become a serious concern worldwide [1]. One of the primary contributors is road vehicles, which account for about one quarter of CO₂ emissions [2]. In order to address the CO₂ pollution problem, many countries have established policies to reduce greenhouse gas emissions in the transportation sector [3]. For instance, 84% of greenhouse gas emissions in Europe come from the transport sector, with 28% primarily associated with ground vehicles. This has led the automotive industry to create low-emission and zero-emission vehicles as alternatives to internal combustion engines. [4].

Currently, electric vehicles (EVs) have begun to play a significant role in transportation services and public use [5]. This shift is largely due to concerns about climate change, which is primarily driven by carbon dioxide emissions. Moreover, fossil fuels are finite resources, prompting many countries to turn their attention to clean energy to reduce air pollution [6]. In addition, EVs also help reduce public noise pollution. EVs have several advantages over internal combustion engine (ICE) vehicles: they are easier to maintain due to fewer moving parts, and they do not release pollutants into the environment. Additionally, ICE vehicles are expected to be phased out by 2035 [7]. Consequently, all new vehicles registered in 2035 are expected to be zero-emission. Numerous governments around the world have recognized transport electrification as a key strategy for reducing CO₂ emissions [8].

Replacing ICE vehicles with BEVs is an effective way to reduce vehicle emissions. Vehicles using lithium-ion batteries emit zero tailpipe gases [9]. Transitioning to BEVs can significantly reduce CO₂ emissions, fine particles, and noise associated with conventional transportation [8]. Additionally, the cost of electrical energy is lower than that of fossil fuels. Many leading countries in electric vehicle adoption have set targets for zero-emission vehicles by 2050. Both the United States (US) and the European Union (EU) plan to achieve net-zero emissions by 2050 [8].

Electric vehicle transformation has evolved from a niche activity pursued by hobbyists and enthusiasts to a rapidly expanding industry [10]. U.S. Electricar, one of the pioneering commercial electric car transformation companies, was established in the 1970s and sold converted versions of conventional cars in the United States using lead–acid battery storage systems [8]. Another notable early converter, Solectria, offered the Force, which was equipped with lead–acid batteries, as well as premium variants featuring longer ranges using nickel metal-hydride batteries [11].

In terms of providing a long-lasting and reliable solution for electrifying vehicles without requiring drivers to purchase brand new EVs, this approach appears to be sustainable. Given the impending 2030 ban on motorized vehicles, many road users may be reluctant to part with their beloved classic cars [12]. Additionally, this solution helps reduce the vast amount of waste generated when cars reach the end of their life cycle [13]. Many classic cars are no longer in production, and parts for their maintenance can be scarce and expensive. In addition, there are still more than six million classic cars on the road, in garages, and in museums [14]. Converting them to electric can extend their lifespan, allowing enthusiasts to continue enjoying them without the constant worry of finding rare parts.

To present new approaches, this research proposes a transformation design utilizing a universal-grade battery motor. This includes designing and calculating the center of gravity (CG) to appropriately balance the vehicle’s weight and determining an optimal battery placement position. This study proposes the use of a classic electric vehicle transformer driven by a PMSM, aimed at adding value to old classic cars by converting them into electric vehicles, thereby reducing environmental pollution. This approach combines the love of classic vehicles with cutting-edge technology and offers a sense of achievement and pride in creating something unique. The existing technology for converting engine-based vehicles to BEVs typically requires the integration of electrical components alongside the existing engine [9].

However, the transformation process described in this paper offers a significant advantage by completely replacing the engine, leading to a substantial reduction in the gross vehicle weight and consequently improving the range of the converted vehicle. Additionally, the system incorporates an in-car power management system and a 3.3 kW multi-charging system capable of communicating with international charging station systems. Following the EV transformation process, analysis and measurement were conducted under three conditions: simulation, dynamometer (dino), and actual on-road testing. The structure of this research is as follows: Section 1 provides an introduction, Section 2 covers the equipment and design, Section 3 details the EV transformation process, Section 4 presents the results and discussion, and Section 5 concludes the study.

2. Equipment and Design

Designing the battery and motor placement is a huge challenge in making a modified electric vehicle. This is because the total weight of the vehicle and the space needed for installing the motor and battery must be considered. Therefore, a 3D scan is required to ensure the proper placement. Figure 1 shows a scan of the available space for the battery of the Jaguar XJ40 after the removal of the engine. In addition, Figure 2 shows the design of the battery and protection distribution unit (PDU). Furthermore,

Table 1. The simulated and experimental information of EV transformation [13].

Components	Specific	Weight
High-voltage battery	LFP 24-cell battery (4 packs/100 volts)	335 kg
Permanent-magnet synchronous motor (PMSM) + controller	30/60 KW, rated peak 60 kW, IP67, 6000 rpm	52 kg
On-board charger	3.3 kW (4 units)	-
Three-phase inverter	Maximum voltage input: 900 Vdc	33.2 kg
Measurement instrument	Power and data analysis: YOKOGAWA DL350

shows the equipment and design for the Jaguar battery placement system, detailing the essential components required for the EV transformation.

2.1. Energy Storage Device

A lithium iron phosphate (LiFePO4 or LFP) battery is a type of lithium-ion battery that utilizes lithium iron phosphate as the cathode material and a graphite electrode with a metal backing as the anode. LFP batteries have low production costs, high safety, low toxicity, and a long service life, making them suitable for use in vehicles and utility-scale stationary applications, as well as for increasing energy reserves. Specifically, cobalt-free LFP batteries have become increasingly popular. As of September 2022, LFP batteries accounted for 31% of the EV market share, with Tesla and BYD alone contributing to 68% of that share. Chinese manufacturers currently dominate the production of LFP batteries. Due to patents expiring in 2022 and a rising demand for more affordable EV batteries, LFP production is projected to grow significantly and potentially surpass lithium nickel manganese cobalt oxide (NMC) batteries by 2028 [15,16,17]. Figure 3 illustrates the performance of LFP batteries. More parameter information can be found in

Table 2. The parameters of LFP battery chemistry [13].

Item	Specifics
Capacity kWh	52.8
Voltage in normal (V)	3.2
Voltage on operation (V)	2.0–3.6
Density of energy (Wh/kg)	90–160
Charging (C-rate)	0.2 C to 1 C
Discharging (D-rate)	1 C
Cycle life	2000–10,000
Thermal runaway	151 °C

. Developing infrastructure to support greater distances and fast charging will facilitate long-distance electric vehicle travel.

2.2. Permanent-Magnet Synchronous Motors (PMSMs)

This research proposes the selection of permanent-magnet synchronous motors (PMSMs) for electric vehicles due to their numerous advantages. PMSMs provide high efficiency, high power density, excellent torque, efficient regenerative braking, low maintenance, precise control, superior heat management, and compatibility with advanced electronic devices [18,19]. In addition, a PMSM is an AC synchronous motor with field excitation provided by permanent magnets, producing a sinusoidal back-EMF waveform. It combines features of both induction motors and brushless DC motors. Combining these features can significantly improve the performance, reliability, and overall driving experience of electric vehicles. Figure 4 illustrates the construction of a permanent-magnet synchronous motor: the standard design is on the left, and the inside-out design is on the right. Table 3 presents the technical parameters of a three-phase permanent-magnet synchronous motor, while Table 4 details the technical parameters of the controller used in EV transformation. The controller manages the various functions of an electric vehicle, including the motor, battery, and other critical systems to ensure the vehicle operates efficiently, safely, and optimally. The software is crucial in managing these functions and continuously improving performance through updates.

The total motor power required is approximately the sum of the power needed for acceleration, top speed (aerodynamic drag), and rolling resistance. A safety margin of 10–20% [20] should be included to accommodate potential losses and contingencies. Figure 5 presents the typical characteristic curves of the selected induction engine where the solid lines represent the nominal torque and the nominal power.

$$P_{total}=P_{acceleration}+P_{drag}+P_{rolling}$$

(1)

Table 3. Technical Parameters of the Permanent-Magnet Synchronous Motor [21].

Item	Specification	Value
Permanent-Magnet Synchronous Motor	Power Rating	~30/60 kW
	Battery Voltage	~365 V
	Net Weight	~42.5 kg
	Rated Speed	~3300 rpm
	Max. Speed	~6000 rpm
	Torque Rate	~120.5 Nm
	Max. Torque	~390 Nm
	Max. Current	~320 A

Table 3. Technical Parameters of the Permanent-Magnet Synchronous Motor [21].

Item	Specification	Value
Permanent-Magnet Synchronous Motor	Power Rating	~30/60 kW
	Battery Voltage	~365 V
	Net Weight	~42.5 kg
	Rated Speed	~3300 rpm
	Max. Speed	~6000 rpm
	Torque Rate	~120.5 Nm
	Max. Torque	~390 Nm
	Max. Current	~320 A

Table 4. Technical parameters of the controller [21].

Item	Specification	Value
Controller	Voltage Rating	~382 V
	Range of Working Voltage	~65–120%
	Output Rated Current	~167 A
	Output Max. Current	~320 A
	Ambient Temperature	−40.5~50.5 °C
	Mode of Control	Vector control
	Mode of Communication	CAN
	Net Weight	~8.9 kg
	Protection Grade	IP67

Table 4. Technical parameters of the controller [21].

Item	Specification	Value
Controller	Voltage Rating	~382 V
	Range of Working Voltage	~65–120%
	Output Rated Current	~167 A
	Output Max. Current	~320 A
	Ambient Temperature	−40.5~50.5 °C
	Mode of Control	Vector control
	Mode of Communication	CAN
	Net Weight	~8.9 kg
	Protection Grade	IP67

2.3. On-Board Charger

The on-board charger (OBC) is a key component that helps the vehicle charge the battery by converting AC to DC [22], which can be stored in the EV’s battery. EV batteries can only store and use DC power, so this transformation is crucial. The OBC manages the charging process, ensuring that the battery is charged safely and efficiently. It monitors and controls the voltage and current to prevent overcharging, overheating, or any other issues that could damage the battery.

Table 5. Parameters of the OBC in electric vehicle transformation.

Parameter	Symbol	Value
Voltage of grid/frequency	Gv/f	220 V/60 Hz
Voltage of DC-link (primary)	Pv	700 V
Voltage of DC-link (secondary)	Sv	350 V
Rated output power	Rp	3.3 kW
Switching frequency	Sf	50 kHz
Nominal phase-shift angle	Npa	13.45°
Capacitance of DC-link (primary)	Pc	470 µF
Capacitance of DC-link (secondary)	Sc	220 µF
Interleaving inductance	Iinduct	1.6 mH
Transformer turns ratio	Ttr	2
Power transfer inductance	Pti	47 µH

shows parameters of the OBC in EV transformation. The others components of EV transformation will also be assembled in the transformation process as shown in Figure 6.

3. Transformation Process

Figure 7 shows a Jaguar XJ40 model with all internal combustion engines removed, which will be replaced by an electrical system including main components are LFP batteries, PMSM, OBC and three phase inverters as shown in Table 1.

The ICE parts and equipment were removed from the vehicle. The ICE was stripped out, including the exhaust system, fuel tank, and other related components, to create space for the electric motor and batteries. These components include the engine and its auxiliary units, the engine’s electrical wiring, the exhaust system, the fuel tank, and the supply system. To accommodate the batteries and alter the vehicle category, the rear bench and back seats, along with their accompanying equipment, were also removed. Figure 8 shows steps to connect the motor to the gear system, which holds the motor and gear in proper position and is installed together (total weight of 342.8 kg). The motor is connected to the gear, minimizing equipment modification. The original gear system of the vehicle is retained, and only the transmission system is changed. One significant advantage is that the gear position remains unchanged, ensuring that the shaft position also stays the same. This consistency contributes to the safety of the suspension by maintaining the original gear load points and gear mount locations. As a result, the need for extensive modifications to the drivetrain during the conversion to electric power is reduced. Additionally, by retaining the vehicle’s original transmission, the anti-lock braking system (ABS) and other braking mechanisms remain intact and well-balanced. This approach ensures smooth driving in accordance with the gear cycle, while also providing optimal tip speed and the ability to handle heavy loads during acceleration. To visualize a transmission system for an EV conversion that connects an electric motor to the existing gears of a traditional internal combustion engine (ICE) vehicle, see the diagram in Figure 9. The electric motor (EM) was subsequently mounted in the vehicle and connected to the gearbox, with a custom-built mounting bracket ensuring that the suspension points of the installed electric motor align with those of the internal combustion engine (ICE), as shown in Figure 10.

At the front and in the trunk of the vehicle, two-sheet steel boxes were installed to house the batteries. The cells were organized into two groups connected both in series and parallel, providing an output voltage of 4 × 12 V. The batteries were linked to the electric motor and integrated with the control unit and variable frequency drives. Then, the AC input of the onboard charger was connected to an external charging port. In addition, the DC output of the onboard charger was connected to the battery pack. This involved a connection to the BMS or a dedicated charging circuit within the battery pack. All of the connections are shown in Figure 11.

Table 6. ICE and EV transformation-specific parameters.

Data	ICE	EV Transformation
Engine	Internal combustion engine	PMSM
Max. Power	123 kW	120 kW
Torque	239 Nm	240 Nm
Max. Speed	4000 rpm	6000 rpm
Weight	1793 mm	1780 mm
Power-to-weight Ratio	10.8 kW/kg	15 kW/kg
Torque-to-weight Ratio	34.3 kgm	35.3 kgm

represents the ICE and EV transformation-specific parameters.

The petrol-filling point was adapted to serve as the charging port. A battery charger was installed to allow the batteries to be recharged from any 110-volt or 220-volt wall outlet. Additionally, the gas gauge was replaced with a voltmeter to indicate the current and battery voltage. The all-schematic Jaguar XJ40, the circuit diagrams of OBC and BMS, the circuit diagrams of the controller and powertrain, and the concept of a BEV using MATLAB are shown in Figure 12, Figure 13 and Figure 14 respectively. The schematic design of an EV is a blueprint that defines how these systems connect, interact, and work together. It is the basis of a vehicle’s performance, safety, efficiency, and user experience. In addition, the drive cycle has been designed according to various parameters to be convenient for all three types of testing, such as simulation, the dynamometer (dino), and actual on-road testing as shown in

Table 7. Key parameters of the driving cycles of the RITA drive cycle.

Parameters	Unit	RITA Drive Cycle
duration	(min)	11.25
distance	(km)	7.64
average speed	(km/h)	60.7
maximum speed	(km/h)	120.17
stop duration	(%)	20.05
constant driving	(%)	35.78
acceleration	(%)	20.12
deceleration	(%)	16.33
positive average (acceleration)	(m/s2)	0.52
positive maximum (acceleration)	(m/s2)	1.58
positive average (speed acceleration)	(m2/s3)	1.29
positive maximum (speed·acceleration)	(m2/s3)	15.08
average deceleration	(m/s2)	−0.44
minimum deceleration	(m/s2)	−1.37

.

4. Results and Discussion

4.1. Simulation and Experimental Setup

The Principle of Resistance Simulation

When the vehicle drives on the road, resistance is determined as follows [23]:

$$T_z={\displaystyle \frac{r}{i_{g }{i}_{0 }\eta }}(mgf+{\displaystyle \frac{C_{D}A}{21.5}} u_a^2 +\mathit{mgi}+\delta m{\displaystyle \frac{du}{dt}})$$

(2)

where rolling resistance is F_f, air friction is F_w, gradient resistance is F_i, acceleration resistance is F_j, the mass of the vehicle is m, the coefficient of rolling resistance is f, the coefficient of air resistance is C_D, the vehicle windward area is A, the speed of vehicle running is u_a, the ramp angle is i, d_u and d_t is velocity and time of EV respectively. The vehicle rotating mass reduction coefficient is δ.

The force on the wheels that the traction motor transmits is as follows [24]:

$$F_z=\sum F={\displaystyle \frac{T_Z{i}_g{i}_0\eta }{r}}$$

(3)

where the traction motor load torque is T_z, the gear box transmission ratio is i_g, the final ratio is i₀, transmission efficiency is η, and the wheel radius is r. Instead of (2) and (3), the traction motor load torque is expressed as the Formula (4).

$$T_z={\displaystyle \frac{r}{i_g{i}_{0 }\eta }}(mfg+{\displaystyle \frac{C_{D}A}{21.5}}{u}_a^2+mgi+\delta m {\displaystyle \frac{du}{dt}})$$

(4)

The relationship between the traction motor speed n and the vehicle running speed u is as follows [25]:

$$n=2.653{\displaystyle \frac{u_a{i}_g{i}_0}{r}}$$

(5)

The meaning of i_g, i₀, and r are shown in Formula (3).

Wheel power (Pw) is determined by the product of the tensile force acting on the wheels (Fw) and the speed of the vehicle [13].

P_W (t) = F_W (t) × v_vehicle (t)

(6)

The determination of the total power available to the wheels is

$$E_W(t)={\int }_o^t{P}_W\left(t\right)dt$$

(7)

The relationship between velocity and acceleration time is defined as

$$V=at={\displaystyle \frac{dv}{dt}} t$$

(8)

W = FD is acceleration work, and F = ma is acceleration force, where the distance (D) moved is in meters [13].

This study analyzes electric vehicle performance using three testing methods: simulation, a dynamometer (dino), and actual road testing. The simulation, conducted in MATLAB/SIMULINK R2016a, follows the RITA drive cycle, covering 7.64 km in 11.25 min with an average speed of 60.7 km/h. The dino test measures power output and torque using a dynamometer, while actual road testing assesses the vehicle’s performance and efficiency in real-world conditions. All three situations will be compared in terms of driving distance, power, and torque. Figure 15 shows the experimental design of the Jaguar XJ40 electric vehicle transformation.

Figure 16 displays the simulated speed profiles of the EV transformation for a single drive cycle. During this cycle, the vehicle accelerated to an initial constant speed of about 61.08 km/h, which it maintained for 137.8 s before decelerating to an idle state. The second cycle began 40 s later, where the vehicle achieved and held a steady speed of approximately 69.6 km/h for 175 s before entering the deceleration phase. After another 40 s interval, the third and fourth cycles featured speeds of around 90 km/h (for 210 s) and 125 km/h (for 230 s), respectively. The final cycle involved accelerating to a constant speed of 138 km/h and maintaining it for 280 s. Figure 17 presents the efficiency map shapes and their corresponding loss contours for the PMSM, while Figure 18 shows the performance simulation curves of the PMSM. In a battery management system (BMS), displaying the battery cell balance information, as shown in Figure 19, can provide insight into the performance and condition of the battery pack. The BMS demonstrates effective cell balancing across all battery cells. From the image, it is evident that each cell has a value of 3.8, indicating that the battery is in good condition. This also shows that the BMS is functioning efficiently, with proper cell balancing contributing to system stability. It prevents the system from shutting down during driving and also indicates the internal resistance status of the battery. These parameters confirm that the battery can be charged according to standards. Furthermore, Figure 20 shows the efficiency of a 3.3 kW multi-charging system. The graph indicates that the stability of the charging systems across all four batteries demonstrates similar efficiency in operation. A multi-charging system provides flexibility and convenience for EV users, enabling them to charge their vehicles from various sources without needing multiple separate systems.

Figure 21 shows 90.47% SOC degradation over the driving cycles of the simulation, dino, and actual road testing. The rate of change of SOC, denoted by ΔSOC, is obtained by taking the difference between the current sample and the previous sample for the SOC signal. Figure 22 and Figure 23 show the power during the charging process in normal mode and acceleration mode, respectively. They also present a comparison of power and torque in BEVs using different testing methods such as dynamometer (dino) simulation and actual road tests. These comparisons offer valuable insights into the vehicle’s performance under various conditions. Here is an overview of these testing methods and their implications: Simulation is useful for early-stage design and optimization but may not fully reflect real-world performance. Dino testing provides a good balance between accuracy and control, useful for tuning and validating the powertrain [26]. Actual on-road testing is essential for final validation and understanding real-world performance and driver experience [27]. In results, the lower power and torque observed during actual on-road testing reflect the numerous real-world variables and inefficiencies that are either controlled or idealized in simulations and dino tests. This makes on-road testing an essential step in evaluating the true performance of BEVs under everyday driving conditions as shown in Figure 24.

In Figure 25, there is a comparison of the driving range of BEVs in different testing methods: simulation, dynamometer (dino), and actual road testing. The simulation is for one drive cycle covering 7.64 km that takes 11.25 min, covering a driving distance of up to 282.14 km. Dino uses a chassis dynamometer to simulate driving conditions while the vehicle is stationary; the driving distance covers 264.68 km. Actual on-road tests conducted on public roads show a driving distance of 259.09 km. Real-world driving conditions include variations in speed, road types, weather, and traffic. The study found that the real-world energy consumption of EVs was generally higher than the values predicted by standardized driving cycles and simulations.

5. Conclusions

In conclusion, the transition from internal combustion engines to EVs has gained significant momentum, driven by the need for sustainable transportation solutions. This study focuses on the transformation of Jaguar XJ40 vehicles to electric power. To ensure compliance with international standards, the equipment used must adhere to established global regulations. The transformation of Jaguar XJ40 vehicles to electric power utilizing PMSMs and their integration with the existing transmission demonstrates significant potential for enhanced efficiency, improved performance, reduced maintenance, and environmental benefits. The comparison of driving ranges through simulation, dynamometer (dino) testing, and actual on-road testing provides valuable insights into the vehicle’s performance across different testing methodologies under consistent conditions. In alignment with Raminthra’s public roads (RITA drive cycle), a single drive cycle encompasses 7.64 km over a duration of 11.25 min. The results indicate that the simulation predicts a driving range of up to 282.14 km. The dynamometer test, conducted using a chassis dynamometer to simulate driving conditions while the vehicle remains stationary, suggests a driving range of 264.68 km. In contrast, actual on-road testing conducted on public roads reveals a driving range of 259.09 km, taking into account real-world conditions, including variations in speed, road types, weather, and traffic. The motor’s peak efficiency is recorded at 95% at a speed of 2400 rpm and a torque of 420 Nm. Furthermore, the percentage difference between the simulated range and the actual road range is approximately 8.17%, indicating that the simulation model is reasonably accurate. This research is therefore deemed successful in the practical conversion of vehicles to electric power, including the selection of equipment and testing in accordance with international standards.