Use a magnetizer to turn these magnets into permanent magnets....

The previous project log got so full I had to split it up to this one.

I added more information to the bot:

"To determine whether the characteristics of a brushless motor with a specific magnetic flux density are considered good or bad, you can evaluate several factors that influence motor performance. Here's how you can approach this:

Magnetic Flux Density Values: For brushless motors, the magnetic flux density (B) typically ranges from 1 to 1.7 teslas (T) for efficient designs. Your calculation of 1 to 2.5 T for an 80 kW motor at 4000 RPM and 300 Nm of torque indicates that you might be targeting higher performance levels. However, while NdFeB magnets can achieve values above 1.0 T, exceeding the recommended limits can lead to issues such as irreversible demagnetization, especially under high thermal stress or external demagnetizing fields [1][5].

Torque and Current Relationships: The torque produced by the motor is directly related to the magnetic fields in the air gap, which are influenced by the current flowing through the windings. When designing your motor, you should consider the maximum current that your motor can handle without overheating. For instance, typical current densities for brushless motors can be around 16 A/mm² [1]. If your design requires higher current densities, it may affect the thermal management of the motor and ultimately its performance.

Torque Ripple and Performance Consistency: Low torque ripple is desirable in brushless motors. A torque ripple of about 2% is considered very low and indicates a smooth operation of the motor [4]. You should aim for designs that minimize fluctuations in torque to improve overall performance.

Thermal Considerations: The performance of magnets, particularly the residual flux density and coercivity, is temperature-dependent. The temperature coefficients for NdFeB magnets indicate that the residual flux density can decrease by approximately 0.10% per °C [6]. Therefore, it is critical to account for the operating temperature range of your motor to ensure that it can maintain performance without demagnetizing.

Design Innovations: Consider innovative rotor designs that can help minimize leakage flux and maximize torque density. Structures like flux barriers can help concentrate the magnetic flux and reduce unwanted leakage, thus enhancing the overall output power density [5].

The maximum magnetic flux for neodymium magnets, particularly the NdFeB (neodymium-iron-boron) type, is a critical factor in the design and performance of brushless motors. The residual flux density (Br) for these magnets is typically around 1.12 T (teslas) at room temperature (20 °C) [1].

Flux barriers in the stator yoke of an electric machine are typically made from non-magnetic materials or air gaps. The primary purpose of these barriers is to increase the magnetic resistance (reluctance) in specific areas, thereby controlling the magnetic flux path and reducing unwanted harmonics.

Here are some common materials and methods used to create flux barriers:

Air Gaps: Simple air gaps are often used as flux barriers. By cutting specific shapes or slots into the stator yoke, designers can create regions where magnetic flux is impeded or redirected.

Non-Magnetic Materials: Materials such as plastics, ceramics, or composites with low magnetic permeability can be inserted into the stator yoke to serve as flux barriers. These materials do not conduct magnetic flux, effectively creating a high reluctance path.

Non-Magnetic Metals: In some cases, non-magnetic metals like stainless steel or aluminum may be used. These materials are structurally strong but have low magnetic permeability, making them suitable for certain designs.