G27 MOSFET Upgrade?

[MrCptDrProf]

Has anyone ever tried upgrading the mosfet on any of the logitech wheels? something similar to the arc mod or the manu-factory powermod?

 

[cnhoff]

What would that do? Allow you to deliver more current to the motor?

 

[MrCptDrProf]

More currrent and voltage, as well as accept a more powerful motor.

 

[Tom_Hampton]

More currrent and voltage, as well as accept a more powerful motor.

Not very likely. That's not how MOSFETs work. MOSFETs don't make current or voltage.

 

[Neilski]

Have never really looked at this but I imagine you'd need to uprate the power supply to have any hope of taking advantage of upgraded MOSFETs.

 

[MrCptDrProf]

i do have plans to upgrade the power supply and motor too. theres a mod out there that uses a 30v psu and heatsinks on the motors and stock mosfet. But i figured to start with the mosfet

 

[cnhoff]

i do have plans to upgrade the power supply and motor too. theres a mod out there that uses a 30v psu and heatsinks on the motors and stock mosfet. But i figured to start with the mosfet

Appreciate your initiative, but the MOSFET merely has to be sized accordingly, so it can handle the current and power dissipated. Changing that on its own will not have an impact.

 

[Tom_Hampton]

i do have plans to upgrade the power supply and motor too. theres a mod out there that uses a 30v psu and heatsinks on the motors and stock mosfet. But i figured to start with the mosfet

As Cnhoff said, a MOSFET in this application is just acting as an electronic switch. It just passes the power available from the supply on to the motor. So, you would need a power supply with a higher voltage in order to drive the motor "harder", and a MOSFET that is capable of withstanding the supply voltage and deliver the additional current.

That's only going to have a marginal impact on the torque available for FFB, though. Besides, the motor is only going to be rated for a certain power / voltage also. So, yes ultimately a stronger motor would be required to have an appreciable impact.

 

[MrCptDrProf]

what if i plan to plug in a 48v 3a powersupply

just wondering how the other mods were done like the ARC mod

ARC_Team G25-e Mod Review

Well, it’s been a while coming, but here at last is the much anticipated ARC Team G25-e Review. For those of you not aware of the G25-e Mod, I will give a brief overview of the conversion and what it does. In essence, the ARC conversion doubles the voltage to the Logitech G25 (or G27) FFB wheel...

www.racedepartment.com

 

[Tom_Hampton]

what if i plan to plug in a 48v 3a powersupply

just wondering how the other mods were done like the ARC mod

ARC_Team G25-e Mod Review

Well, it’s been a while coming, but here at last is the much anticipated ARC Team G25-e Review. For those of you not aware of the G25-e Mod, I will give a brief overview of the conversion and what it does. In essence, the ARC conversion doubles the voltage to the Logitech G25 (or G27) FFB wheel...

www.racedepartment.com

Did you read the whole review?

It doesn't discuss the details. But, it does give an overview of the complexity. I am an electrical engineer for the last 30 years. At the conceptual level what has to happen is this:

1. The interface board has to be updated to ensure that the incoming 48 VDC voltage is properly divided down for the internal voltage regulator that manages the control circuitry (USB interface, microcontroller, MOSFET drivers, etc).
2. With double the input voltage there will be additional power dissipation everywhere (motor, mosfets, interface voltage regulator, etc). This will require additional cooling (heatsinks, fans, etc). There are several methods of voltage regulation....each with their own considerations.
3. The motor needs to be evaluated for compatibility at the higher voltage and current / power. All this is pointless, if you just burn up the motor in an hour.
4. Some interface board circuit changes are likely needed to allow the 48VDC goes to the motor or MOSFET depending on the method that's been chosen to control the motor. There are a couple ways that this could have been done.
5. The selected MOSFET (or MOSFETs) has to be compatible with the supply voltage, the inrush and operating current of the motor, and control scheme.

None of these things are especially hard. But, they do require some level of electrical engineering....or the purchase of a prepared kit and instructions.

 

[MrCptDrProf]

Did you read the whole review?

It doesn't discuss the details. But, it does give an overview of the complexity. I am an electrical engineer for the last 30 years. At the conceptual level what has to happen is this:

1. The interface board has to be updated to ensure that the incoming 48 VDC voltage is properly divided down for the internal voltage regulator that manages the control circuitry (USB interface, microcontroller, MOSFET drivers, etc).
2. With double the input voltage there will be additional power dissipation everywhere (motor, mosfets, interface voltage regulator, etc). This will require additional cooling (heatsinks, fans, etc). There are several methods of voltage regulation....each with their own considerations.
3. The motor needs to be evaluated for compatibility at the higher voltage and current / power. All this is pointless, if you just burn up the motor in an hour.
4. Some interface board circuit changes are likely needed to allow the 48VDC goes to the motor or MOSFET depending on the method that's been chosen to control the motor. There are a couple ways that this could have been done.
5. The selected MOSFET (or MOSFETs) has to be compatible with the supply voltage, the inrush and operating current of the motor, and control scheme.

None of these things are especially hard. But, they do require some level of electrical engineering....or the purchase of a prepared kit and instructions.

Yes I actually have and would actually prefer to purchase a kit, but I dont think the mod is available for purchase anymore. Also I mentioned that i did have plans to put heatsinks and fans on the motors and the other components on the board. I do understand that it's not as simple as just replacing the mosfets, motors and power supply, I just thought the mosfet would be a good place to start.

 

[Tom_Hampton]

Ok.

Well, the only thing I can say is that I would not take apart my wheel until I had a complete design for the whole setup. Specifically, how to upgrade the power supply voltage without damaging the internal electronics, because there isn't a point to any of the other changes if you can't figure out how to do that.

After that, if you want to do it a step at a time... sure you could start with the mosfets...they will work with the original power supply just fine.

 

[johnuhtron20]

Ok.

Well, the only thing I can say is that I would not take apart my wheel until I had a complete design for the whole setup. Specifically, how to upgrade the power supply voltage without damaging the internal electronics, because there isn't a point to any of the other changes if you can't figure out how to do that.

After that, if you want to do it a step at a time... sure you could start with the mosfets...they will work with the original power supply just fine.

Not sure if this is still relevant as its been 5 or 6 months. But I run a 12v PSU routed to a 1500w Stepup module I got off ebay for £25, that has been adjusted to put out exactly 30v. I have smooshed the current up quite high, probably around 4 or 5 amps. The result is quite impressive. I have at least doubled the force feedback force. Very noticeable when cornering at high speeds!. I had to add cooling as it was getting rather warm. I just ran some 12v server fans off the 12v PSU. Quite cheap to do, especially if you already have a spare psu laying around that sits under the ouput voltage of the stepup. I would say that you shouldn't need to play around with the internal board other than to add cooling. The motors and IC all seem to handle it like a champ. FYI I'm using a g27.