I have drawings of magnets with physical dimensions, materials, tolerances, etc. How do I add a Magnetic Flux requirement (weber, volt second) so I can measure the magnet when is arrives and be sure that it is fully magnetized? I know how to add this to the drawing literally however where do I...
Does anyone know where I can get a magnet characterized for all four quadrants. Electron Energy use to offer this service but it doesn't show up on their website any longer.
Clyde Hancock
Design & analysis of electric motors and generators
www.motorconsultants.com
I’m looking for some help with respect to skin effect. On a PM synchronous motor, the windings are subjected to the rotational frequency from the PM rotor and to PWM frequency that is driving the motor. I feel that the fundamental frequency of the rotor is the main contributing factor to skin...
I'm looking for information about a winding machine for large diameter wire in a DC armature. I have seen this machine (a long time ago) and I think it was called an "Able" winder. It doesn't wind in the traditional sense (fly, needle, shed, etc.), instead you have to cut the magnet wire to...
If I subject unmagnetized Neo to elevated temperature but stay below the curie temperature will this adversely affect the magnet when later magnetizing? In other words, will I still be able to fully magnetize the magnet after it cools?
Clyde Hancock
Design & analysis of electric motors and...
Using the magnet thickness and airgap thickness to construct a load line (Bd/Hd) to determine the operating point on the normal curve, and then adding 1 (Bd/Hd +1) I should be able to have a line parallel to this to intersect where the intrinsic curve drops 10% and read the reverse field...
I'm working with a supplier to magnetize a full rotor (multiple magnets, Neodymium). They state that they can only get an average of 95% saturation for each magnet (simulation). What are the risks to not fully saturating the material?
Clyde Hancock
Design & analysis of electric motors and...
Below is the formula for calculating the mechanical time constant (Parker Hannifin).
Tau(m) = (R*J)/(Ke*Kt)
R: winding resistance
J: rotor inertia
Ke : back EMF constant
Kt : torque constant
For a three phase PM brushless motor is the resistance line to line or phase? What are the units for...
Excerpt from LakeShore Measuring Permanent Magnet Characteristics with a Fluxmeter and Helmholtz Coil
"Deriving Intrinsic Flux Density
The magnetic moment of interest in permanent magnet testing is generally
defined as the intrinsic flux density per unit volume of magnet. Based on the
magnetic...
Can Neo be magnetized easier by raising the temperature during magnetization?
Clyde Hancock
Design & analysis of electric motors and generators
www.motorconsultants.com
Does anyone know the state of the industry for aircraft electric motor development, globally? I'm referring to full size aircraft, not models or small drones. I know that the internet has information, as an example, Rolls-Royce set out three years ago to build the world’s fastest electric...
Does anyone know of a cross reference for electrical steel lamination properties. I'm looking for a data base or document(s) that has the various named materials and show their equivalent materials (see attached). I would like to have as many of the various materials offered as I can get. I...
I have recently been told that Hiperco 50 loses a significant portion of it's desired magnetic properties after laser cutting for stators. Is this true? I have not heard this before.
Clyde Hancock
Design & analysis of electric motors and generators
www.motorconsultants.com
How is a DC motor operated bi-directional with three wires. I have had an inquiry for a DC permanent magnet motor to have three wires, with the third wire determining the direction of the motor. All the searching that I've done always leads to a three phase motor or an AC motor. I think that...
I have a client that is going to have an outside stator generator wound with multiple strands of wire. The supplier that is offering the winding equipment says they will be "needle" winding this stator with one conductor at a time, doing several iterations until the number of strands is met...
I have been told that for lager motors a Megger test is better than a Hipot test. That is to say, lager motors will fail a Hipot test and not a Megger test (I'm not sure exactly how that makes the Megger test better). I have looked through the posts and could not find anything referencing...
I have a fuel pump motor that is submerged in the fuel tank (gasoline). I'm having an issue with the brush life when the speed and flow rate is increased (increased current). I have researched the issue in the Engineering Tips forums as well as internet search and I've found some (very little)...
I have just started to see the warning below in a spread sheet that I'm creating. This is the first time I've seen this and as far as I know it doesn't stop me from saving the file or reopening and editing. Anyone know what this is about?
Clyde Hancock
Design & analysis of electric motors...
I have been trying to find a video that shows how an outside stator PM synchronous motor is wound if the stator is skewed. Typically the stator is stacked "loose" with just the cuffed slot liners holding the stack together. Then the shed/transfer winding method is used to insert the coils in...
