Controller circuit for Hilden Brandt motor needed..

[Nali2001]

Hi Aladinlamp,
About1:
Well what you really want in any motor is that the torque produced is constant through the whole 360 degree cycle.
In for example my (test) model you only have torque when the rotor and stator line up. And between these 'attraction cycles' there is a huge area of 'no attraction action' so no torque, that means the gained momentum is all there is to get to he next attraction phase. In Jacks 3 valve motor (although I did never see the internal rotor) I presume that the each valve covers an rotor area of 120 degrees. So that the next valve goes into attraction when the previous valve has just finished an attraction phase. In that way there is a somewhat constant torque. And the more valves there are the better it gets. Like 6 valves, 9 valves. But it is all rpm dependent as well. At high rpm you won't notice a high torque ripple that much.

About2:
The best core material is a material which 'holds' the most magnetism at the desired frequency. The normal silicon steel transformer laminations is good enough. They are used in every electric engine and transformer. Plus they are much cheaper then 'superior' materials. There are some variations in these silicon steels, some have higher saturation levels and/or higher working frequencies than others, also there is the issue of steel grain alignment:

There are two main types of electrical steel: grain-oriented and non-oriented.

Grain-oriented electrical steel usually has a silicon level of 3% (Si:11Fe). It is processed in such a way that the optimum properties are developed in the rolling direction, due to a tight control (proposed by Norman P. Goss) of the crystal orientation relative to the sheet. Due to the special orientation, the magnetic flux density is increased by 30% in the coil rolling direction, although its magnetic saturation is decreased by 5%. It is used for the cores of high-efficiency transformers, electric motor and generators.

Non-oriented electrical steel usually has a silicon level of 2 to 3.5% and has similar magnetic properties in all directions, which makes it isotropic. It is less expensive and is used in applications where the direction of magnetic flux is changing, such as electric motors and generators. It is also used when efficiency is less important or when there is insufficient space to correctly orient components to take advantage of the anisotropic properties of grain-oriented electrical steel.

The steel in normal transformers and electric motors is nearly always 'Non-oriented'. The C cores http://www.alphacore.com/images/Cut-Core.JPG I use as valves are 'Grain-oriented' and might be an advantage.
I get them here: http://www.alphacoredirect.com/index.html?lmd=39452.612164

If you really want to go wild and high speeds. Then one would use some tape wound nanocrystalline material like the grain aligned C cores from http://www.metglas.com/
But price is a huge issue in this field so it is no option. But they are far superior over normal silicon steel laminations specially for high permeability at high frequencies. But like I said, normal silicon steel laminations is good enough for electric motors at this stage. And besides working with steel laminations is tough enough. Never mind that brittle corroding metglas. To sum up what one wants in these attraction motors is a big attraction-surface area and as tight as possible air gaps (keep terminal steel expansion and bearing wear in mind)

Regards,
Steven

[aladinlamp]

Hi Aladinlamp,
About1:
Well what you really want in any motor is that the torque produced is constant through the whole 360 degree cycle.
In for example my (test) model you only have torque when the rotor and stator line up. And between these 'attraction cycles' there is a huge area of 'no attraction action' so no torque, that means the gained momentum is all there is to get to he next attraction phase. In Jacks 3 valve motor (although I did never see the internal rotor) I presume that the each valve covers an rotor area of 120 degrees. So that the next valve goes into attraction when the previous valve has just finished an attraction phase. In that way there is a somewhat constant torque. And the more valves there are the better it gets. Like 6 valves, 9 valves. But it is all rpm dependent as well. At high rpm you won't notice a high torque ripple that much.

About2:
The best core material is a material which 'holds' the most magnetism at the desired frequency. The normal silicon steel transformer laminations is good enough. They are used in every electric engine and transformer. Plus they are much cheaper then 'superior' materials. There are some variations in these silicon steels, some have higher saturation levels and/or higher working frequencies than others, also there is the issue of steel grain alignment:

There are two main types of electrical steel: grain-oriented and non-oriented.

Grain-oriented electrical steel usually has a silicon level of 3% (Si:11Fe). It is processed in such a way that the optimum properties are developed in the rolling direction, due to a tight control (proposed by Norman P. Goss) of the crystal orientation relative to the sheet. Due to the special orientation, the magnetic flux density is increased by 30% in the coil rolling direction, although its magnetic saturation is decreased by 5%. It is used for the cores of high-efficiency transformers, electric motor and generators.

Non-oriented electrical steel usually has a silicon level of 2 to 3.5% and has similar magnetic properties in all directions, which makes it isotropic. It is less expensive and is used in applications where the direction of magnetic flux is changing, such as electric motors and generators. It is also used when efficiency is less important or when there is insufficient space to correctly orient components to take advantage of the anisotropic properties of grain-oriented electrical steel.

The steel in normal transformers and electric motors is nearly always 'Non-oriented'. The C cores http://www.alphacore.com/images/Cut-Core.JPG I use as valves are 'Grain-oriented' and might be an advantage.
I get them here: http://www.alphacoredirect.com/index.html?lmd=39452.612164

If you really want to go wild and high speeds. Then one would use some tape wound nanocrystalline material like the grain aligned C cores from http://www.metglas.com/
But price is a huge issue in this field so it is no option. But they are far superior over normal silicon steel laminations specially for high permeability at high frequencies. But like I said, normal silicon steel laminations is good enough for electric motors at this stage. And besides working with steel laminations is tough enough. Never mind that brittle corroding metglas. To sum up what one wants in these attraction motors is a big attraction-surface area and as tight as possible air gaps (keep terminal steel expansion and bearing wear in mind)

Regards,
Steven

OK thanx for info

1.i see there many sizes of C-cores, you think bigger is better in this case, when it comes to sizing the machine?

2.Is there noticable benefit in performance, if you cut the section to the core for coil winding ? Why you cut it just from one side and not equaly from both sides?

3.Do you have experience with computer controlled triggering, swithing and pulsing ? When the rotor comes to the right position, i would like to trigger it by some opto switch and hall effect switch, but from this point everything will be PC controlled and monitored

So what can be the setup for this scenario ?_

Thanx

[Nali2001]

With this machine bigger (cores) is always better. But remember that the biggest they stock is still not as big (cross section wise) as Jacks valves. But when you have big interaction surfaces then the air gap becomes less and less an issue. I mean for a rc toy motor 0.1 is a big air gap but for a 500hp induction motor 0.1 is hyper small. This is probably one of the reasons why Jack reached o.u when he went big, like 2"x2" magnets (which are huge...) I only am able to use 20mmx20mm.
Now before you start spending like $100.00 a core remember that these are also made of laminates (only tape wound) and super care must be taken when machining since the lamination are only held together with insulation epoxy. And a mill will tip the thing apart with ease. And also the rounding out of the core 'end parts' or 'fingers' is tricky to say the least.

About the section out of the core where the coil goes.
1/2 of the core MUST be taken away. Jack knows why.
It is not that mystical to understand but kinda hard to put in words. You want the core section that the coil is wound on only to be as big as to be able to allow all the magnets magnetism to pass through. The idea is that it is a 'valve'. So when you magnetize that core section you saturate it and it becomes a blockade for the field of the magnet, and it has to find another route. In that way you send out the field of the coil and field of the magnet combined through the rotor. But you see if you don't cut out 1/2 of the core way you do two things wrong. First you need to magnetize way to much core then really needed and second you saturate the whole core with the coil So that the magnets magnetism has no room anymore in the core and might even be destroyed in the process. Keep this a rule. 1/2 of the core is for the coil 1/2 of the core is for the magnet. Combined they make up the lot and can comfortably work together.

The reason why I do not cut some away from both sides is because machining laminates fuses the machined lamination ends together and so 'shorts' out the laminations that would in a perfect world be totally isolated from each other to lower eddy current losses. So if you machine only one side you do less damage.

No I don't use computer timing. Just an opto and mosfet switching circuits and pwm for some fine tuning.

Steven

[Elisha]

@Steven

Hi, How are the numbers for your motor input, output energy?

How to difficult is to make a 12V 70 Amper car alternator with the Hildenbrand or Flynn parallel path ?

Thanks.

[Nali2001]

Hi Elisha,
My unit is not finished yet, so I have no test data.

'How difficult it is' you ask?
Well for Jack it is probably not all that hard, only lots of work. If I had all the serous machines, materials and funds (which I don't have) I would attempt a big size machine myself since the 'Tech' from both Hildebrand and Flynn is not all that hyper difficult to grasp. But Jack is the only one who has lots of experience and working models, so it is a damn shame he is tied up right now, financely (however ya spell that) and health wise. Here we have a person in our mids who really goes hands on and is now unable to press forward. I myself don't even have my mini version finished. So I'm not really the one to speak anyway. But I would say this. If you have the machines (lathe and mill) and some experience with moderate precision works you can build a small version yourself and work from there. Or if you have the money you can maybe also get the lamination laser cut or something. A car alternator is indeed a good and cheap generator.

Regards,
Steven