Overview
As the electric vehicle (EV) market continues accelerated growth, along with the proliferation of other related e-Mobility applications, electrical motor designs are undergoing significant design transformation to deliver the higher performance, smaller form factors and manufacturing efficiency needed to stay ahead of the curve.
Overall, the trend in EV powertrain design is towards higher voltage architectures, improved power density, and reduced size and weight. These advancements are critical for improving the performance and efficiency of EVs and making them more competitive to enable a global transition from gasoline-powered vehicles.
This e-Mobility update article looks specifically at the role being played by new power connector technologies such as motor stator busbars and multi-phase busbars for enabling the transformation to next-gen motors.
Trends in EV Powertrains and Other Motor Designs
Electric vehicle powertrains and other e-Mobility applications have seen significant advancements in recent years, with a focus on improving performance and reducing the size and weight. Some key trends include:
- Higher voltage architectures: EV manufacturers are increasing the voltage of their battery packs and powertrains to reduce losses and improve efficiency. This has led to the development of high-voltage systems, such as 800V systems, which offer higher power density and faster charging times.
- Improved power density: Improving power density is a key as manufacturers focus on increasing the power output of the motor while reducing its size and weight.
- Integration of power electronics: Power electronics, such as inverters and DC-DC converters, are becoming increasingly integrated into the EV powertrain. This integration improves efficiency and reduces the size and weight of the power electronics system.
- Lightweight materials: The use of lightweight materials, such as aluminum and carbon fiber, is becoming more common in EV powertrain design. These materials reduce the weight of the powertrain, improving the vehicle’s range and performance.
- Diversity of motor design requirements: In addition to changes in the primary EV powertrains, there is a rapidly expanding range of other motor requirements, including on-board power steering and motion controllers as well as compact powertrains for applications such as 2-wheel scooters, warehouse vehicles, etc.
The Importance of Multi-Phase Power
Multi-phase power designs will be important in next-gen EV powertrains for several reasons:
- Higher Power Density: Multi-phase power designs allow for higher power density, meaning that more power can be generated from a smaller and lighter motor.
- Improved Efficiency: Multi-phase power designs offer higher efficiency due to reduced winding losses, improved power factors, and better use of the magnetic core. This translates into longer range and reduced charging times for EVs.
- Smooth Operation: Multi-phase power designs provide smoother operation and reduced torque ripple, resulting in a more comfortable and stable ride for passengers.
- Better Control: Multi-phase power designs allow for better control over the motor, which is important for safety and performance. This is particularly important in electric vehicles, where precise control over the motor is needed for regenerative braking and traction control.
- Future-Proofing: Multi-phase power designs offer scalability for future upgrades, allowing for higher power output as technology evolves. Therefore, e-Mobility powertrains designed with multi-phase power can be easily upgraded in the future without significant changes to the underlying design.
As described in the following sections, new-generation motor stators and phase busbars are opening up a new spectrum of design flexibility and robust power connectivity to accommodate both near-term and longer-term future requirements.
Motor Stator Busbars
Innovative new customizable technologies for motor stators are giving designers the flexibility to rapidly implement advanced multi-phase motors for optimizing current flow, compact form factors, robust thermal performance, faster assembly, and an overall lower cost of deployment.
These efficient, one-piece solutions minimize weight and space while maximizing configurability and optimizing performance. In addition to eliminating bulky wiring hassles and costs, new-generation motor stators provide a solid foundation for creating robust connections between stator windings and external power sources.
Motor stator busbars are designed to accommodate hairpin windings typically used in advanced higher-voltage motor stators along with a range of flexible multi-phase connections.
Using multi-layer construction and high performance copper, these stamped and wire-formed motor stators include options for integrating high dielectric insulators and offer a variety of connection techniques. Connection methods include multi-phase stator bars to handle 3-phase or 6-phase application requirements, along with options for brazing, pluggable, laser welding, or bolt-on.
Overmolding with high performance plastic creates a complete and ready-to-use solution that handles high-temperatures and provides long product lifecycles.
Multi-Phase Busbars
Phase busbar solutions provide robust connectivity for multi-phase power interfaces to support a range of e-Mobility applications. These can be deployed either as co-designed solutions with the motor stators or in other related power connectivity requirements.
Constructed with high performance copper, high temperture plastic molding or overmolding, and various sealing options, ENNOVI phase busbars are designed for harsh environments and long lifecycles.
Fully customizable, this next-generation phase busbar technology can accommodate options such as:
- Low and high voltage requirements
- Integrated control circuitry to reduce complexity and weight
- Laminated magnetic cores to minimize eddy currents and enable current sensing capabilities
- Connection options for laser welding, brazing, or bolt-on
- Straight, 90-degree, or custom-angled connector tabs
Summary
With EVs and other e-Mobility applications becoming a larger share of the overall vehicle market, automotive makers are facing increased competition, faster design cycles and tighter cost constraints. To compete in this rapidly changing market, the need for a widening variety of customizable power interfaces for traction drives and other motor configurations now represents a critical success factor.
As an experienced leader in busbars and other interconnects for the automotive industry, ENNOVI has a long track record of pioneering innovation, which once again is being leveraged to provide highly configurable and robust custom busbar technologies for traction motor stators and multi-phase power interfaces.
Since there is no “one-size-fits-all” approach to motor stators and phase busbar designs, automotive companies need access to vendors with a proven track record across all the disciplines to support Tier 1 engineers with end-to-end design of customized solutions.
ENNOVI has the experience and expertise, and we have created a broad-based foundation of configurable and adaptable technologies, such as the busbar and motor stators described here, from which we can provide initial design support, rapid prototyping, testing and ramp-up to full production. These capabilities are also backed by the ENNOVI worldwide design, distributed manufacturing, and logistics organization that provides unparalleled local support for automotive makers around the globe.
