Distributed Drive Electric Portal Axle for Next-Generation E-Buses
We offer an advanced distributed drive electric portal axle solution designed for public transport electrification. This solution features a dual-motor wheel-end drive, enabling compact integration, high torque output, and precise torque control.
It delivers a simplified drivetrain with improved efficiency, reduced vehicle weight, and up to 40% fewer components. The design supports energy regeneration, electronic differential control, and smooth dynamic response.
Ideal for low-floor configurations, our electric portal axle enhances passenger accessibility and is well-suited for city buses, highway coaches, and trolleybuses seeking improved performance and energy efficiency.
Email: contact@brogenevsolution.com
Solution Details
Our electric portal axle for buses features a dual-motor distributed drive scheme. This setup ensures complete independence between the left and right power systems. Each power system comprises a PMSM motor, a 2-speed AMT, and a wheel-side reducer. With the adoption of electronic differential technology, the left and right drive systems are independently controlled, enhancing overall performance and maneuverability.
Basic Structure
- With high torque and power density, the two PMSM drive motors provide a strong and reliable output.Â
- The wheel-side reducers on each side reduce the motor output speed while amplifying the torque delivered to the wheels.
- The 2-in-1 motor controller controls the left and right motors to operate at the desired speed, angle, direction, and response time.
- Integrated with advanced motor control and shifting logic, the 2-speed AMT improves hill-climbing ability, optimizes cruising efficiency, and reduces the need for oversized motors, while maintaining driving comfort and vehicle stability.
Working Principle
- The VCU calculates the total torque demand based on the driver’s acceleration or deceleration intent.Â
- The electric drive control unit (DCU) allocates the total torque between the left and right drive motors based on the steering angle, vehicle posture sensors, and road surface traction coefficients.Â
- The left and right motor controllers (or 2-in-1 integrated motor controller), upon receiving the instructions, convert the energy from the battery to the necessary power for the drive motors, ensuring the vehicle’s stability and handling.
Technical Specifications
| Model | OEEA1100K | OEEA1400K | OEEA2100N |
| Â |  |  | |
| Rated Axle Load | 9000 kg | 9000 kg | 13000 kg |
| Maximum Output Torque | 2×6142 N.m | 2×6142 N.m | 2×10776 N.m |
| Maximum Output Power | 2×90 kW | 2×120 kW | 2×160 kW |
| Maximum Wheel Speed | 540 rpm | 541 rpm | 430 rpm |
| Tire Specs (Standard) | 305/70R22.5 | 275/70R22.5 | 275/70R22.5 |
| Gear Ratio | 17.55 | 17.55 | 18.58 |
| eAxle Assembly Weight | 750 kg | 850 kg | 1080 kg |
| Rated Voltage | 540 VDC | 540 VDC | 540 VDC |
The parameters may vary depending on the configuration. For more parameter information, please contact us at contact@BrogenEVSolution.com
Leading the Way in Innovative Electric Bus Powertrain Technology
Advanced Control Strategies
Our distributed drive control algorithms have been continuously optimized over more than a decade across various vehicle types and operating conditions. Today, they are among the most advanced in the public transport sector. Our engineering team has in-depth expertise in key control strategies such as EDS, EASR, IRBS, and IESS.
Electronic Differential System (EDS)
Regulates the speed or torque of the drive motors on each side during cornering, enabling precise differential steering for smoother and more controlled turns. Our EDS has been proven over millions of kilometers.
Electronic Acceleration Slip Regulation (EASR)
Leading torque control algorithm with millisecond response time enhances safety and reduces tire wear.
Intelligent Regenerative Braking System (IRBS)
Ensure braking performance while recovering energy in various driving conditions to reduce overall energy consumption and extend driving range.
Intelligent Electronic Stability System (IESS)
Adjust the torque of various components in real-time based on the overall vehicle status to ensure safety and stability of the vehicle under extreme conditions.
- Without EASR: Tire slippage and directional instability may occur on wet or slippery surfaces, leading to reduced control.
- With EASR: The vehicle maintains smooth and stable operation on slippery roads by actively regulating wheel slip.
- Without IESS: During high-speed cornering or sudden obstacle avoidance, insufficient or excessive steering may cause the vehicle to deviate from its intended path or even result in rollover.
- With IESS: In unstable driving conditions, the system enhances vehicle stability by intelligently adjusting the torque or braking force of individual drive wheels.
- 18 km/h, traditional bus axle
- 18 km/h, Brogen electric portal axle with mature & stable EDS
Adaptive Electronic Differential Road Test
Speed (km/h) | Inner and outer wheel speed ratio | Theoretical speed ratio | Test deviation | |
|---|---|---|---|---|
Brogen Electric Portal Axle | 12 | 0.7914 | 0.7655 | 3.38% |
15 | 0.79 | 3.2% | ||
Traditional Bus Axle | 12 | 0.7987 | 3.73% | |
15 | 0.7911 | 3.35% |
1. Empower Your Electric Bus Design
Our electric portal axle adopts a wheel-side motor design that eliminates traditional drivetrain components such as the driveshaft, final drive, and differential. This results in a shorter power transmission path, higher efficiency, and a more compact structure. With flexible electrical connections replacing many mechanical linkages, the overall vehicle design becomes more adaptable and optimized.Â
Ride Comfort
Full low-floor design increases passenger space and improves boarding efficiency; enhanced passenger safety through optimized cabin layout and accessibility
Lightweight Design
Reduces overall vehicle weight by approximately 200 kg, contributing to better efficiency and handling
Energy Efficiency
Utilizes parallel-axis helical gears with perfectly matched forward and reverse gear surfaces; enables up to 100% regenerative torque, improving energy recovery and reducing energy consumption
Safety and Stability
Independent control of left and right wheel torque enables precise slip ratio management; minimizes tire slippage and wear, especially under slippery conditions (e.g., rain or snow); supports active yaw moment control to enhance vehicle stability; achieves ASR and ESP functions without additional hardware cost
Central Direct Drive
- Short development cycle, but high manufacturing cost
- Occupies significant X-axis space, limiting battery layout flexibility
- Heavier drivetrain due to retained traditional driveshaft
- Lower overall transmission efficiency
Electric Portal Axle
- Enables the lightweight design
- Improves the overall vehicle layout
- Supports the fully flat low-floor design
- Higher transmission efficiency
1. Increased Interior Space & Lower Floor Height
The compact design enables a full low-floor layout, creating a flat and step-free central aisle from the front door to the rear axle. This design trend is crucial for modern urban city buses, offering improved accessibility, faster passenger flow, and a more spacious interior.
2. Lightweight Design & Lower Energy Consumption
Reducing vehicle weight is critical for improving energy efficiency. Studies show that every 10% reduction in vehicle weight can lead to a 6-8% decrease in energy consumption. Our integrated electric portal axle solution supports high-speed motor operation and shared cooling lines, reducing the need for long cables and additional components - lowering overall mass, volume, and cost.
3. Enhanced Vehicle Performance
Traditional single-motor direct drive setups often struggle with hill climbing and high-speed acceleration. Our dual-motor wheel-end configuration distributes power demands more efficiently, enabling better dynamic response, higher power density, and improved gradeability - especially in challenging terrains.
4. Greater Design Flexibility
The modular nature of the electric portal axle offers unprecedented freedom in vehicle layout. Battery packs can be placed under the floor or on the roof for better axle load distributions. Its compact and highly integrated design also makes it suitable for various new energy bus types - including hybrid electric buses, fuel cell electric buses, and articulated buses. For example, a 18-meter articulated city bus can be equipped with one or two electric portal axles, depending on the design needs.
2. Why Distributed Drive Approach?
Traditional Electric Powertrain
- Centralized Drive → Poor driving maneuverability
- Centralized Brake → Long braking distance
- Centralized Steering → Large turning radius
- Long Mechanical Transmission Chain
- Significant energy transmission losses;
- Poor applicability across vehicle models;
- Insufficient passenger space
Distributed Drive Electric Powertrain
- Drive / Brake Decoupling
- Distributed Drive → Enhanced control on complex surfaces
- Distributed Brake → Reduced braking distance on complex surfaces
- Distributed Steering
- Four-wheel Independent Steering → Reduces turning radius; enables lateral movement and zero-radius turns; significantly enhances maneuverability
- Eliminates Mechanical Transmission → Increases user space; reduces energy transmission losses
- The dual-motor electric axle delivers higher power and torque, offering clear advantages for applications such as highway coaches.
- Among dual-motor configurations, the distributed drive system stands out due to the elimination of the mechanical differential. This results in reduced weight, a more compact design, lower oil churn losses, and enhanced safety performance.
- In demanding applications where high torque and power are essential, the distributed drive architecture offers significant advantages over centralized drive systems.
Rich Experience in E-Powertrain R&D
Our core founding team includes highly experienced vehicle design experts who have been engaged in the development of electric vehicles and e-powertrains since 2009. Over the years, they have built deep expertise in industry standards, specifications, FMEA methodologies, and practical engineering know-how.
The team also has strong simulation and analysis capabilities across all levels – from individual systems and subsystems to complete vehicles.
- 108 design specifications and technical guidelines
- 188 high-level in-house simulation and analysis standards
- 510 key design metrics and review checkpoints
- 600+ PCR library and FMEA cases
Modern Production Facilities
We currently operate two dedicated production bases for distributed electric drive axles, with an annual production capacity of approximately 8,000 units. An additional headquarters and manufacturing facility is under construction and is expected to be operational by the end of this year, bringing the total projected annual capacity to 20,000 units.
Our intelligent manufacturing lines for distributed drive eAxles are among the most advanced in the industry, both in terms of process sophistication and quality control. Every product undergoes 100% full-function testing in a custom-built acoustic testing room, covering load performance, temperature rise, rotational speed, ABS, NVH, and safety compliance.
Applications
Our electric portal axle systems have been successfully deployed at scale in both domestic and international public transport fleets. They are widely used in city buses, coaches, airport shuttles, and trolleybuses ranging from 10 to 18 meters in length. These systems have proven reliable in diverse operating environments – from hot climates like the United Arab Emirates to cold, high-altitude regions in Central Asia.
The system is now in mass production and ready for large-scale deployment.
Hydrogen buses with 320 kW eaxles.
Buses with the low-floor design.
Airport shuttle bus with 14T eaxles.
Pure electric buses with our eaxles.
Electric Portal Axle Factory
Electric Portal Axle Factory
Electric Portal Axle Factory
Electric Portal Axle Factory
Frequently Asked Questions
Yes, our electric portal axles are in full-scale mass production and have been deployed in volume on public transport vehicles across various countries, including the UAE, France, the UK, Turkey, and others.
Our electric portal axles are designed for a wide range of applications, including 10 to 18-meter electric city buses, coaches, trolleybuses, airport shuttle buses, and articulated buses.
For bulk orders, we can replace components with the customer-specified brands upon request.
We follow a strict quality management system. However, for clients we haven’t yet partnered with, these documents are considered confidential and cannot be shared.
We provide standard or extended warranties depending on the product. For bulk orders, we prepare spare parts in advance to minimize downtime and ensure efficient handling of any warranty claims.
Contact Us
Get in touch with us by sending us an email, using the Whatsapp number below, or filling in the form below. We usually reply within 2 business days.
Email: contact@brogenevsolution.com
Respond within 1 business day
Whatsapp: +8619352173376
Business hours: 9 am to 6 pm, GMT+8, Mon. to Fri.
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