The difference between single motor and dual motor drive system

With the intensification of the energy crisis and the improvement of environmental protection requirements, new energy vehicles are attracting more and more attention. In the drive system of new energy vehicles, the motor is one of the most important components. At present, there are two main drive systems for new energy vehicles on the market: single motor drive and dual motor drive. So, which one is more durable between the two?

01

The difference between single motor and dual motor

A single-motor drive system means that the vehicle is equipped with only one motor, which outputs power through the transmission system to drive the wheels. A dual-motor drive system, on the other hand, means that the vehicle is equipped with two motors, one motor outputs energy to the front wheels and the other motor outputs energy to the rear wheels. The front and rear wheels are independent of each other, so the dual-motor system has stronger driving ability and power output. At the same time, the load distribution of the two motors is more balanced, which can effectively extend the life of the motors.

02

Durability comparison

Although the single-motor drive system is relatively simple, the problems or failures it causes are relatively simple, so it is easy to repair and maintain. However, in terms of performance and control system, the single motor is obviously not as adaptable as the dual-motor system, and under long-term high-speed driving conditions, the motor temperature and pressure of the single-motor drive system are relatively high, which has a certain impact on the motor life.

In comparison, the dual-motor system can not only output more powerful power, but also has better acceleration performance and higher control accuracy. At the same time, because the motor load is distributed more evenly, it is better than the single-motor system, so the overall durability is also more outstanding.

03

What are the common dual-motor cars?

1Dual induction motor

Mercedes-Benz EQC

In terms of electric motors, the Mercedes-Benz EQC uses a combination of front and rear dual-induction asynchronous motors, with two asynchronous motors located on the front and rear axles respectively. In order to reduce energy consumption, the vehicle is also equipped with an intelligent powertrain system. The front motor has been optimized to achieve optimal efficiency under medium and low speed loads, while the rear motor is responsible for providing stronger power to keep the vehicle performing better. The maximum power of the entire electric system is 300kw, the peak torque can reach 765N.m, the acceleration time from 0 to 100km/h is 5.1 seconds, the maximum speed can reach 180km/h, and the energy consumption per 100 kilometers is about 25kW·h.

Audi e-tron

The structural features of the Audi R8 etron central dual-motor configuration are similar to the centralized motor drive configuration. Two drive motors and two reducers are arranged oppositely on the frame, connected to the wheels through longer half-axles, and independently drive the wheels on both sides. Its unsprung mass is small, the manufacturing technology is mature, and it is easy to apply and install. However, the transmission system still requires universal joints and transmission half-axles, and occupies a certain chassis space, resulting in limited interior design space. It is generally used in high-performance cars or trucks.

NIO ES8 Founder Edition

ES8 is equipped with XPT's "three-in-one" dual-motor drive system, equipped with front and rear induction + permanent magnet dual motors. The XPT 100-300kW induction electric drive system platform takes into account both economy and performance. It supports combination with electric drive systems of different types and powers, and is especially suitable for front auxiliary drive configured as four-wheel drive models. The first product of the induction electric drive platform has a 240kW high-power, high-performance asynchronous induction motor, a large torque of 420N·m, and a transmission efficiency of more than 97%. It can still achieve stable and strong power output at high speeds. The XPT 240-300kW induction electric drive system platform takes into account both economy and performance. It supports combination with electric drive systems of different types and powers, and is especially suitable for front auxiliary drive configured as four-wheel drive models. The extremely low drag loss performance helps to improve the vehicle's range.

2Dual permanent magnet motors

BYD Han

In July 2020, BYD Han EV 4WD and 2WD (front) versions were launched. Based on the "e+ platform", the front "3-in-1" drive assembly of the 4WD version of Han EV has a maximum speed of 15,500 rpm and a maximum output power of 163 kW; the rear "3-in-1" drive assembly has a maximum speed of 15,500 rpm and a maximum output power of 200 kW, and the SIC electronic control suppresses the overload and overheating of the drive motor; the blade battery system is loaded with 76.9 kWh of electricity and has a maximum charging power of 100 kW; the vehicle weighs 1.9 tons and has a NEDC range of 550 kilometers.

Xiaopeng P7 four-wheel drive version

The four-wheel drive high-performance version of Xiaopeng P7 has a permanent magnet synchronous motor on the front and rear axles. In terms of power parameters, the maximum power of the front motor is 196kW and the maximum torque is 390Nm; the maximum power of the rear motor is 120kW and the maximum torque is 265Nm. Overall, it can burst out a maximum power of 316kW and a maximum torque of 655Nm. Basically, it can stabilize the power level of a 3.0T performance car.

The motor, electronic control and reducer are highly integrated to form a high-performance three-in-one electric drive system. Compared with the traditional decentralized electric drive layout, the three-in-one electric drive system has higher efficiency, more compact structure, lighter weight, more regular interior layout and stronger reliability.

Porsche TaycanTaycan

Permanent magnet synchronous motors are used at the front and rear. The rear motor is more powerful, providing 449 horsepower and 406 lb-ft (550Nm, but Turbor S can provide 450lb-ft - 610Nm). The advantages of permanent magnet synchronous motors over induction motors (Tesla uses induction motors) are high efficiency (more obvious at medium and low speeds), small size, and better heat dissipation performance, but the price is relatively high.

3Permanent magnet synchronous + induction asynchronous dual motor

Tesla Model 3 Performance Edition & Model Y
Tesla Model 3 still uses AC asynchronous motors on the front axle and permanent magnet synchronous motors on the rear axle. Compared with AC asynchronous motors, permanent magnet synchronous motors are more compact, have higher operating efficiency, longer battery life, and are easier to control.

Tesla continues to use the permanent magnet synchronous motor solution in Model Y. The combination of induction and permanent magnet drive motors can make better use of the characteristics that the induction motor has a high efficiency area at high speed and the permanent magnet motor has a high efficiency area at low speed, and complement the efficiency of the two working areas.

All-new NIO ES8

The 23 ES8 still uses dual-motor four-wheel drive, which is also standard for the flagship model. The new car is equipped with front and rear dual-motor four-wheel drive, using a front 180kW permanent magnet + rear 300kW induction motor, with a system total power of 480kW, a peak torque of 850N・m, and a zero-to-hundred acceleration of 4.1 seconds. In addition to the power upgrade and stronger performance, the front and rear motors are smaller in size and have a certain improvement in efficiency.

Volkswagen ID Series
In terms of motors, the Volkswagen ID.4CROZZ adopts a configuration of asynchronous induction motor in the front motor + permanent magnet synchronous motor in the rear motor. The 2024 ID.6 CROZZ offers a variety of options to meet the needs of different consumers. The rear-wheel drive version is equipped with a permanent magnet synchronous motor with a peak power of up to 150kW and a peak torque of 310N·m. In terms of endurance, according to the CLTC comprehensive working conditions, the endurance can reach 601km. The PRIME model is a dual-motor four-wheel drive version, equipped with a front AC asynchronous motor and a rear permanent magnet synchronous motor, with an output torque of 162/310N·m, a peak output power of 80/150kW, and a endurance of 560km.

04

Purchase suggestions

When choosing a drive system for a new energy vehicle, the specific needs of the user should be considered. If the high performance and control accuracy of the vehicle are important, a dual-motor system can be selected. However, if the user has no special requirements for vehicle performance and control mode, a single-motor system can also be considered. In addition, factors such as the vehicle brand, energy conversion efficiency, and cruising range also need to be considered comprehensively.

In short, durability is one of the important indicators for selecting a new energy vehicle drive system. After comprehensive comparison, the dual-motor drive system is more durable than the single-motor drive system. When choosing, you should consider the brand of the vehicle and user needs, comprehensively evaluate multiple indicators, and choose the most suitable new energy vehicle drive system.