Dual-Motor Independent Drive: A Technological Breakthrough for Mini and Compact Electric Loaders
1. Technical Background and Innovative Architecture
As the electrification of construction machinery advances, mini and compact loaders—due to their unique advantages in confined-space operations, municipal maintenance, and agricultural applications—have become a key focus for the deployment of electric technology. Unlike conventional large loaders, mini and compact loaders impose higher demands on the powertrain in terms of compactness, energy efficiency, and precision of control.
The AILISHENG ALS340EV Pro, ALS916EV, ALS920EV, ALS920EV TELE, ALS928EV, and ALS936EV series of electric loaders adopt a dual-motor drive architecture consisting of one permanent magnet synchronous travel motor that directly drives the front and rear axles (eliminating the need for a transmission and torque converter) plus one permanent magnet synchronous hydraulic motor. This architecture represents the mainstream direction for the development of mini and compact electric loader technology. Academic research indicates that the dual-motor solution, which uses separate motors for the hydraulic system and the travel system, has become the mainstream choice for constructing purely electric loader systems. Industry leaders such as XCMG are also actively developing dual-motor drive technology; XCMG's recently published patent (CN119116669A) explicitly adopts a dual-motor drive structure, replacing a single large motor with two smaller ones to reduce system hardware requirements and improve energy efficiency.
2. Core Technical Advantages of Dual-Motor Drive
2.1 Complete Decoupling Control of Travel and Hydraulic Systems
Conventional loaders use a single engine as the power source, with the travel system and hydraulic system sharing the same power supply. This results in the hydraulic system idling and consuming energy even when work implements are not in use. The AILISHENG dual-motor solution achieves physical isolation and independent control of the travel motor and the hydraulic motor.
The travel motor is dedicated to vehicle propulsion, directly driving the front and rear axles and completely eliminating the need for a transmission and torque converter. This simplified design not only reduces power transmission losses but also makes travel control more direct and precise. The hydraulic motor independently drives the hydraulic pump to provide power for work implements, operating only when the bucket or other attachments are in use, thereby fundamentally eliminating idling energy consumption. Industry practice shows that the dual-motor independent drive solution allows for separate and independent control of the pump motor and the travel motor, resulting in greater power and energy savings.
2.2 Complementary High-Efficiency Zones and System Energy Optimization
The dual-motor architecture provides greater opportunities for energy optimization. According to XCMG's patented technology, employing two motors with different high-efficiency zones—one focused on the low-to-medium torque region and the other on the medium-to-high torque region—can cover all output scenarios across the machine's low, medium, and high torque ranges. Through appropriate torque control, the drive system can always operate within its high-efficiency zone.
The AILISHENG dual-motor solution draws fully from this technological concept. The travel motor is optimized for the driving conditions typical of mini and compact loaders, maintaining high efficiency within the commonly used travel speed range. The hydraulic motor is specifically calibrated for operating conditions such as lifting and dumping. This strategy of scenario-specific optimization leads to a significant improvement in overall system energy efficiency.
2.3 A Revolution in Transmission: Direct Drive Without a Transmission
Traditional mini and compact loaders, constrained by space, often use relatively simple transmissions with limited efficiency. The AILISHENG dual-motor solution uses the travel motor to directly drive the front and rear axles, completely eliminating the transmission and torque converter, achieving a revolutionary simplification of the transmission system.
The advantages of this design are manifold: first, transmission efficiency is greatly improved, as mechanical and hydraulic losses from the transmission and torque converter are avoided; second, system reliability is enhanced due to a significant reduction in potential failure points along the transmission path; third, maintenance costs are lowered, eliminating the need for transmission fluid changes and torque converter service; fourth, the overall vehicle layout becomes more compact, freeing up valuable space in mini and compact loaders for other possibilities.
2.4 Native Support for Energy Recovery
The dual-motor independent drive architecture creates favorable conditions for energy recovery. When the loader brakes or descends a slope, the travel motor can switch to generator mode, converting the vehicle's kinetic energy into electrical energy to recharge the battery. Practice with XGMA purely electric loaders shows that adding an analog electrical signal output from the brake pedal to feed brake actions back to the controller allows braking energy to be recovered during deceleration, reducing brake system wear and improving electrical energy utilization.
This feature is particularly useful in the frequent start-stop operating scenarios common with mini and compact loaders. Additionally, the independent hydraulic motor also holds energy recovery potential during lowering operations. When the bucket or boom descends by gravity, the hydraulic motor can help control the descent speed and recover some potential energy.
2.5 Precision Control with Fully Electrified Operation
Permanent magnet synchronous motors are inherently known for their fast response and high working efficiency. Combined with the dual-motor independent control strategy, AILISHENG achieves fully electrified, precision control of both travel and work operations.
The travel motor directly drives the front and rear axles, resulting in smoother starting, acceleration, and deceleration. Its infinitely variable speed characteristic completely eliminates the shifting shock associated with conventional transmissions. The independent control of the hydraulic motor enables finer, more precise operation of work implements, allowing operators to use electronic control joysticks for accurate bucket movements, thereby improving work efficiency and operational comfort.
2.6 Performance Assurance of Permanent Magnet Synchronous Motors
Permanent magnet synchronous motor technology is mature and highly reliable, having been widely validated in the construction machinery sector. The AMXE series permanent magnet synchronous water-cooled motors from industry-leading supplier ABB are specifically developed for off-highway vehicles and commercial vehicles, featuring compact size, reliable performance, excellent efficiency, and high power density. The second-generation battery-powered utility vehicles developed by Epiroc in cooperation with ABB utilize permanent magnet synchronous motor drive systems; using electric equipment has reduced ventilation costs by 50% compared to using diesel equipment, demonstrating a significant energy efficiency improvement.
AILISHENG's high-performance permanent magnet synchronous motors fully incorporate advanced industry experience and are optimized for the specific operating conditions of mini and compact loaders, delivering exceptional energy efficiency while providing robust power.
3. Comprehensive Technical Benefits
In summary, the dual-motor independent drive solution yields the following comprehensive technical benefits:
Enhanced Controllability: Direct drive of front and rear axles by the travel motor enables infinitely variable speed and smooth driving. Independent control of the hydraulic motor allows for precise and responsive work implement movements.
Optimized Energy Efficiency: Complete decoupling of travel and hydraulic systems eliminates idling losses. Complementary high-efficiency zone control ensures the system always operates at its optimal efficiency point. Energy recovery functions further extend runtime.
Increased Reliability: Elimination of the transmission and torque converter simplifies the transmission path and significantly reduces potential failure points. Permanent magnet synchronous motor technology is mature and highly reliable.
Simplified Maintenance: No need for transmission fluid changes or torque converter service. Lower motor maintenance requirements reduce total lifecycle operating costs.
Compact Layout: Simplified transmission system frees up valuable space in mini and compact loaders, facilitating vehicle integration and potential battery capacity expansion.
Foundation for Intelligence: The fully electrified architecture provides native hardware support for future autonomous driving and remote control applications.
4. Conclusion
The dual-motor drive solution employed by the AILISHENG ALS340EV Pro, ALS916EV, ALS920EV, ALS920EV TELE, ALS928EV, and ALS936EV series represents an important direction for the development of mini and compact electric loader technology. Through the coordinated control of one travel motor directly driving the front and rear axles and one independent hydraulic motor, it achieves a revolutionary simplification of the transmission system and a significant improvement in energy efficiency. The solution demonstrates outstanding advantages in controllability, reliability, maintenance cost, and intelligence potential.
As industry research indicates, the dual-motor solution with separate motors for the hydraulic and travel systems has become the mainstream technical path for purely electric loaders. With continued advancements in permanent magnet synchronous motor technology and the ongoing optimization of control strategies, dual-motor independent drive is poised to become the standard configuration for mini and compact electric loaders, driving the electrification of construction machinery toward deeper and broader applications.