Five-Motor Independent Drive: The Technological Innovation Path for Electric Skid Steer Loaders

I. Technical Background and Innovative Architecture

Amidst the wave of electrification in construction machinery, skid steer loaders have become a key model for electrification transformation due to their flexible and versatile operational characteristics. Traditional skid steer loaders mostly adopt a power transmission chain of "engine - hydraulic pump - hydraulic motor - wheel end," which features a complex structure, low energy transfer efficiency, and makes precise independent control of each drive wheel difficult to achieve.

The AILISHENG ALS3090EV electric skid steer loader adopts a five-motor drive solution, consisting of four permanent magnet synchronous wheel-side travel motors + one independent permanent magnet synchronous hydraulic motor. This architecture is highly aligned with the forefront of industry technology. Referring to relevant technical literature, using one master controller to manage five motor controllers, which simultaneously and independently control the five motors to drive the loader's wheel rotation and hydraulic pump operation, has become a mainstream technical route for electric skid steer loaders. In this setup, the four travel motors independently drive the left-front, left-rear, right-front, and right-rear wheels respectively, while the fifth motor is dedicated to driving the hydraulic pump, supplying power to the working implements.

II. Core Technical Advantages of the Five-Motor Drive

2.1 Precise Independent Control of the Travel System

Traditional skid steer loaders use hydraulic transmission, making it difficult to accurately feedback and adjust wheel speed differences. In contrast, the ALS3090EV's four-wheel independent wheel-side motor solution achieves genuine **four-wheel independent drive and control**.

By having the vehicle control unit (VCU) collect signals from the electronic travel control lever in real-time, the motor controllers can independently output precise speed and torque commands to the four travel motors, while simultaneously receiving real-time status feedback from the motors, forming a closed-loop control system. This architecture allows each wheel to obtain independent power output based on operating conditions. When a zero-turn maneuver is required, the wheels on the left and right sides can rotate in completely opposite directions, achieving a turning radius approaching zero and fully leveraging the skid steer loader's mobility advantages.

More critically, the four-wheel independent control technology enables rapid adjustment of the control current for each drive assembly based on speed differences between the wheels, thereby accurately regulating the speed or torque at the wheel ends and achieving real-time four-wheel closed-loop control. This not only reduces unnecessary energy loss but also avoids vibration and impact issues caused by speed differences during travel, significantly enhancing the vehicle's ride comfort and operational smoothness.

2.2 Independent Optimized Control of the Hydraulic System

In traditional designs, the hydraulic pump often shares a power source with the travel system, leading to energy consumption from idle rotation even when the working implements are not in operation. The ALS3090EV fundamentally solves this problem by using an independent hydraulic motor to drive the hydraulic pump.

This design allows for precise control of the hydraulic system independent of the travel system. When the loading implements are inactive, the hydraulic motor can be completely stopped, avoiding idle energy consumption. By optimizing the control algorithm of our product, the ALS3090EV, through a reasonable energy-saving mode control, the system can automatically put the main pump motor into standby mode when the operator does not depress the foot pedal and the parking pressure reaches a set value. As soon as the system detects the operator depressing the foot pedal to operate the working implements, the main pump motor immediately resumes operation. This on-demand power supply method is estimated to improve the vehicle's overall range by approximately 15% without affecting the operator's control experience.

2.3 Energy Recovery and System Efficiency Improvement

The five-motor architecture creates favorable conditions for energy recovery. When the skid steer loader decelerates or goes downhill, the four travel motors can switch to generator mode, converting the vehicle's kinetic energy into electrical energy to recharge the battery system. This function is particularly useful in the frequent start-stop operating scenarios typical of skid steer loaders, further extending operational time.

Furthermore, permanent magnet synchronous motors are inherently highly efficient. Combined with the five-motor independent control strategy, the ALS3090EV achieves significantly higher energy utilization compared to traditional hydraulic transmission solutions. Each motor operates within its optimal efficiency range, avoiding the throttling and overflow losses inherent in traditional hydraulic systems.

2.4 Foundation for Full Electrification and Intelligence

The five-motor drive architecture naturally aligns with the trend towards intelligentization. As every actuating component achieves motorized control, the entire machine can realize full electrification, laying the hardware foundation for functions such as autonomous driving and remote control.

Based on this architecture, the control system can implement more complex logical functions, such as automatically adjusting the hydraulic motor speed according to different gears, controlling the direction and speed of the hydraulic motor based on the work mode, and achieving more sophisticated coordinated control between travel and working implements. These functions are extremely difficult to realize with traditional hydraulic transmission solutions but become relatively straightforward on the five-motor electric platform.

III. Summary of Comprehensive Technical Benefits

In summary, the ALS3090EV's five-motor independent drive solution delivers the following comprehensive technical benefits:

• Enhanced Controllability: Four-wheel independent precision control enables true zero-turn radius and refined travel control.
• Optimized Energy Efficiency: The independent hydraulic motor operates on-demand, eliminating idle losses and significantly improving operational range.
• Increased Reliability: The closed-loop control system monitors the status of each wheel in real-time, reducing mechanical shocks and vibrations caused by speed differences.
• Simplified Maintenance: Eliminates complex hydraulic transmission components, simplifies the power transmission path, and reduces potential failure points.
• Foundation for Intelligence: The fully electronic control architecture provides native support for future autonomous driving and intelligent operation systems.

IV. Conclusion

The five-motor drive solution of the AILISHENG ALS3090EV represents a significant direction in the technological development of electric skid steer loaders. Through the coordinated control of four travel motors and one hydraulic motor, it achieves independent optimization of the travel system and the working system, demonstrating remarkable advantages in controllability, energy efficiency, reliability, and potential for intelligence. With the continuous optimization of control strategies and advancements in battery technology, the five-motor independent drive is expected to become the standard technical route for high-end electric skid steer loaders, driving the electrification of construction machinery to deeper levels.