BLDC Engines Enable the Future of Motors

Sensors Insights by Rüdiger Laschewski-Grossbaier

For some time, BLDC motors have been known, particularly in the automotive industry, as being “ripe” for a breakthrough. Their advantages include precisely controlled motor operation, heightened performance of the entire application, and less wear. Yet, these advantages come with disadvantages that can be corrected in the design phase.

BLDC engines will see increased integration with sensors and actuators in the coming years, enabling not just autonomy, but also the detection and collection of detailed information about conditions and surroundings.

BLDC motors have been known for quite some time, particularly in the automotive industry, as being “ripe” for a breakthrough. They have great potential since they allow for precisely controlled motor operation, heightened performance of the entire application, and less wear. These advantages, however, include disadvantages.

For motor control, a micro-controller is necessary, which includes a program that monitors the exact commutation of the half bridges by itself. Inaccurate designs result in a lack of precise motor control, producing, for instance, vibrations when the motor is running at low speeds. Increased performance of the entire application means that the entire design must be put to the test. This includes the design of the engine.

Consequently, there are not only higher development costs but also manufacturing costs if, for example, the motor design requires a certain level of precision to obtain both repeatable and reproducible comparable performance. Less wear can be achieved by observing system parameters. With the aid of a high-performance micro-controller (which helps exact commutation), changes to the system parameters and readjustment can be ensured over the lifetime of the application. Nevertheless, how can we refer to BLDC engines as technology enablers when considering the increased initial costs for the overall system?

Fig.1: This BLDC motor is illustrated with the HVC 4223F embedded motor controller from TDK-Micronas.
Fig.1: This BLDC motor is illustrated with the HVC 4223F embedded motor controller from TDK-Micronas.

 

Smart Electronics in Development

Due to high cost pressures in the industry, improvements in performance or product lifetime are particularly helpful when they produce noticeable benefits for the customer. For applications in which, for instance, the smoothness of the engine is perceived directly by the customer, BLDC motors are on the rise. But what more is there to it?

This is where new technologies and their implementation in vehicles come into play. Connectivity, distributed intelligence, predictive maintenance, and digital twin are all well-known buzzwords in the industry and yet their implementation in smart actuators in automobiles has yet to be fully exploited. Particularly in the field of digital features, big changes can be expected soon.

 

Applications in Vehicles

Let’s have a closer look at the background behind some of these keywords in terms of their real-life applications. Sensor data fusion and redundant software, which allow for the calculation of manipulated variables or the provision of data tables in distributed networks, will both be indispensable for optimizing ever-growing numbers of network nodes. Sensor data fusion plays a major role.

On the one hand, it enables the diagnosis and comparison of data from similar sensors, vital for increased automatization of the car. On the other hand, it extends the detected database beyond merely data volume by increasing the reliability of the data as well as by expanding and deepening the amount of overall data by combining different sensor classes.

This has a cost-cutting effect since the function of dedicated sensors can be covered by existing ones. Furthermore, it can also have a function-expanding effect if data can be gathered and mapped from sensors not available to the system. Predictive maintenance is achievable via the ever-increasing number of intelligent and smart actuators in automobiles.

A failure of the motor, electronics, or mechanics of the actuator due to wear or misunderstood environmental influences can be delayed by matching expected and achieved measures in the system. Above a certain delta, targeted intervention ensures compliance with the prescribed measures. Through integration, notification to the outside world can be made in advance before failure occurs. It is even possible to distribute sensor or calculation tasks between individual actuators in the car. Of course, mechanical actuation must continue onsite.

Fig.2: The reuse principle ensures optimum utilization of all network components.
Fig.2: The reuse principle ensures optimum utilization of all network components.

 

Applications in Vehicle Actuators

The motor control module as the central element of actuators and their networking will play a decisive role in the future. Thus far, development has predominantly been on isolated applications and rudimentary use of the network for the exchange of information and diagnostic data. In the future, the focus will be on the actuator itself, the networked information, and the actuator base.

Fig.3: An actuator housing with motor, gears and the Micronas embedded motor controller (Source: FORD) is compared to an actuator housing with motor and gears (Source: FORD).
Fig.3: An actuator housing with motor, gears and the Micronas embedded motor controller
(Source: FORD) is compared to an actuator housing with motor and gears (Source: FORD).

To create added value to automobiles by using new technologies, such as sensor data fusion or predictive maintenance, significant reductions of CO2 emissions into the environment can also be achieved. In addition, areas that require further autonomy and anticipatory signals, for example, diagnosis data, can be transmitted to workshops. In this case, not only self-diagnosis can be carried out but also the state of other actuators can be checked and transmitted in case of non-plausible data or an inability to communicate.

 

Outlook

The number of small and smart actuators in automobiles has skyrocketed in recent years. For many previously non-existing or “old-fashioned” functions, there are now automated solutions that reduce the workload for the driver and support a reduction in CO2 emissions. The next step will be to redefine replacement of these parts. Data from different areas of the car will be connected in a network and thereby used by a variety of actuators. This will result in operating conditions that will largely be optimally designed.

Fig.4: The Smart Car is no longer a dream of the future.
Fig.4: The Smart Car is no longer a dream of the future.

The working condition of the car will be available predictably and lead to a completely new driving experience with data transmitted from the outside world. The data will be made available to the driver in a transparent manner and can also be evaluated within the vehicle or online so that vehicles can go for maintenance before parts become defective and possibly, the car can also be serviced while waiting for the next journey.

This is supported by optimized production processes and shortened troubleshooting for the vehicle. Optimized, faster, more accurate, and better informed - the increased amount of electronics and intelligence within the vehicle, distributed across sensors and actuators, will enable vehicles to not only drive autonomously but also provide detailed information about their condition at any time as well as anticipatory information to enable intervention.

 

About the author

Rüdiger Laschewski-Grossbaier is the Head of Marketing & Application Engineering, PL eMotor Control at TDK-Micronas GmbH. He has been active in the automotive industry since 1996. In February 2015, Mr. Laschewski-Grossbaier transferred to TDK-Micronas and took over the product area of embedded motor controllers. Here, he can leverage the extensive experience he has gained from previous positions in micro-controller engineering, project management for micro-controller software development and automotive networking, as well as technical marketing for automotive analog ASIC.