Futuristic electric motor with glowing magnetic fields demonstrating flux-weakening control

Unlock the Future: How Hybrid Memory Machines are Revolutionizing Electric Motor Control

Kai Mendoza in Tech & Innovation September 2025 • 4 min read.

"Combining Flux-Weakening and Magnetization State Manipulation for Unprecedented Motor Performance"

In today's rapidly evolving technological landscape, the demand for high-performance electric motors is greater than ever. Industries ranging from electric vehicles to wind power generation require motors capable of operating efficiently across a wide range of speeds while delivering robust torque. However, traditional motor designs often struggle to meet these competing demands, especially when constrained by fixed voltage supplies.

A promising solution lies in the realm of memory machines (MMs), a novel type of motor that directly regulates the magnetization state of its low coercive force (LCF) permanent magnet material. By manipulating the magnetic properties of the motor itself, MMs offer the potential to overcome the limitations of conventional designs and achieve unprecedented levels of performance.

This article delves into the innovative world of hybrid permanent magnet axial field flux-switching memory machines (HPM-AFFSMMs) and explores how combining flux-weakening control with magnetization state manipulation can unlock new possibilities for electric motor technology. We'll examine the design principles, control strategies, and performance characteristics of these advanced machines, shedding light on their potential to revolutionize a wide range of industrial applications.

How Hybrid Memory Machines Redefine Motor Control

Futuristic electric motor with glowing magnetic fields demonstrating flux-weakening control

At the heart of the HPM-AFFSMM lies its unique ability to directly control the magnetization state (MS) of the low coercive force (LCF) permanent magnet (PM) material. This is achieved through a dedicated magnetization winding that allows for precise adjustment of the magnetic flux within the motor. Unlike traditional motors with fixed PM excitation, HPM-AFFSMMs can dynamically adapt their magnetic properties to optimize performance across a wide range of operating conditions.

The benefits of this approach are multifold:

Extended Speed Range: By manipulating the magnetization state, the motor can effectively weaken the magnetic flux at high speeds, allowing it to operate beyond its base speed without exceeding voltage limits.
Enhanced Torque Output: The ability to regulate the magnetic flux also enables the motor to maximize torque output at lower speeds, providing improved acceleration and load-handling capabilities.
Reduced Copper Loss: Unlike traditional flux-weakening techniques that rely on injecting d-axis current, HPM-AFFSMMs can achieve flux weakening without incurring significant copper losses, leading to improved efficiency.
Robust Rotor Structure: With the PMs, armature, and magnetization windings all located on the stator, the rotor design is simplified, resulting in a more robust and reliable machine.

To harness the full potential of the HPM-AFFSMM, sophisticated control strategies are required. These strategies involve carefully coordinating the flux-weakening control and magnetization state manipulation to achieve optimal performance across the entire speed range. This involves considering factors such as the control mechanism, current distribution strategy, and voltage and current trajectory.

The Future of Electric Motors is Here

The development of HPM-AFFSMMs and their advanced control strategies represents a significant step forward in electric motor technology. With their ability to deliver wide speed range operation, large torque output, and improved efficiency, these machines hold immense promise for a wide range of applications, from electric vehicles and wind power generation to industrial automation and robotics. As research and development in this field continue, we can expect to see even more innovative solutions emerge, further pushing the boundaries of what's possible with electric motors.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1109/tec.2018.2864556, Alternate LINK

Title: Flux-Weakening Control Combined With Magnetization State Manipulation Of Hybrid Permanent Magnet Axial Field Flux-Switching Memory Machine

Subject: Electrical and Electronic Engineering

Journal: IEEE Transactions on Energy Conversion

Publisher: Institute of Electrical and Electronics Engineers (IEEE)

Authors: Gongde Yang, Mingyao Lin, Nian Li, Guangying Tan, Beibei Zhang

Published: 2018-12-01

Everything You Need To Know

What is a hybrid permanent magnet axial field flux-switching memory machine (HPM-AFFSMM) and how does it work?

An HPM-AFFSMM is a novel type of electric motor that uses a low coercive force (LCF) permanent magnet (PM) material and a dedicated magnetization winding to directly control its magnetization state (MS). This allows the motor to dynamically adjust its magnetic properties. The magnetization winding allows for precise adjustment of the magnetic flux within the motor. Unlike traditional motors with fixed PM excitation, HPM-AFFSMMs can adapt their magnetic properties to optimize performance across a wide range of operating conditions, offering extended speed ranges and enhanced torque output.

How does the HPM-AFFSMM extend the speed range compared to traditional electric motors?

The HPM-AFFSMM extends its speed range by manipulating the magnetization state (MS). At high speeds, the motor can effectively weaken the magnetic flux. This 'flux-weakening' allows it to operate beyond its base speed without exceeding voltage limits. Traditional motors often struggle with this, especially when constrained by fixed voltage supplies, whereas the HPM-AFFSMM offers a more efficient and controllable method.

What are the key advantages of using an HPM-AFFSMM in terms of performance and efficiency?

HPM-AFFSMMs offer several key advantages. They provide extended speed ranges and enhanced torque output, leading to improved acceleration and load-handling capabilities. They also reduce copper loss compared to traditional flux-weakening techniques, resulting in improved efficiency. Furthermore, the rotor design is simplified due to the placement of the PMs, armature, and magnetization windings all on the stator, leading to a more robust and reliable machine. All this leads to a superior motor design.

How does the HPM-AFFSMM achieve flux weakening without the drawbacks of traditional methods?

Unlike traditional flux-weakening techniques that rely on injecting d-axis current, HPM-AFFSMMs can achieve flux weakening without incurring significant copper losses. This is a major advantage because injecting current to achieve flux weakening in traditional motors often leads to increased losses and reduced efficiency. The HPM-AFFSMM's ability to manipulate the magnetization state of the low coercive force (LCF) permanent magnet (PM) material allows for a more efficient and controlled flux weakening process.

In which applications can HPM-AFFSMMs be implemented, and what future advancements can we anticipate?

HPM-AFFSMMs hold significant promise for various applications, including electric vehicles, wind power generation, industrial automation, and robotics. The technology's ability to deliver wide speed range operation, large torque output, and improved efficiency makes it suitable for these demanding applications. Future advancements are expected to involve even more innovative solutions as research and development in this field continues, further pushing the boundaries of what's possible with electric motors, promising further improvements in performance, efficiency, and control.