I have a few questions. First please look at the below image:
This is one of many versions of a typical 12 volt system motorcycle shunt regulator. Unlike an automotive regulator where a field es excited a motorcycle regulator takes a voltage off a 3 phase stator, rectifies it and applies it to the battery using a shunt design to keep the voltage down. This is apparent in the above drawing. The circuit uses PWM from a simple 555 circuit to drive the MOSFET.
A little history here. Last year I was happily tooling along and went to do a lane change. No turn signals! So I mess around when I get home and notice my battery gauge is showing something like 7 volts. So I remove the stator to regulator connection and start measuring phase to phase, turns out my bike has a 3 phase system. Yank regulator and trot to my local Harley shop. Surprise, the bike did not have original OEM Harley system. Doing some homework I discover someone upgraded the stock charging system to a Thunder Heart Performance 3-Phase Charging System. The entire system cost about $500 and all I need is the regulator. At 1,000 RPM I get about 20 VAC phase to phase and it increases 20 V / 1,000 RPM just like it should. The manufacturer sells only the full kit so I get a brand new stator and rotor I don't need and the regulator which I really need. A tiny little silver box which takes 5 min to swap out. So I bought the system. This was almost a year ago.
So a few says ago I am out for a ride and turn signals quit working so here comes that sinking feeling as I look at the voltmeter. It was erratic but did return to about 13.6 volts. This is exactly like deja vue all over again. I called JP Cycle and they were no problem and gave me a link to a return UPS label, I figured I was screwed but nope so in a week or so I should have another new kit. I returned the brand new rotor and stator from last year still in the packaging. This setup is a 38 amp charging system.
Then I started thinking about these regulators and as can be seen there isn't much to them. A three phase rectifier 100V 50A isn't much then I thought rather than a 555 for PWM and a IRF540 I could use an IRL540 N Channel Mosfet and drive it using a uC like an Arduino which I have a few chip only with sockets, Maybe use a 10 turn 100K pot as a divider into an analog input and generate a PWM out to drive my uC. Analog in and PWM out. The IRL 540 should hack the shunting duty. Can anyone think of why this approach won't work? Really not much to it and thought I would kick it around for something to do. I think I came in just under the wire on that exchange.
Ron
This is one of many versions of a typical 12 volt system motorcycle shunt regulator. Unlike an automotive regulator where a field es excited a motorcycle regulator takes a voltage off a 3 phase stator, rectifies it and applies it to the battery using a shunt design to keep the voltage down. This is apparent in the above drawing. The circuit uses PWM from a simple 555 circuit to drive the MOSFET.
A little history here. Last year I was happily tooling along and went to do a lane change. No turn signals! So I mess around when I get home and notice my battery gauge is showing something like 7 volts. So I remove the stator to regulator connection and start measuring phase to phase, turns out my bike has a 3 phase system. Yank regulator and trot to my local Harley shop. Surprise, the bike did not have original OEM Harley system. Doing some homework I discover someone upgraded the stock charging system to a Thunder Heart Performance 3-Phase Charging System. The entire system cost about $500 and all I need is the regulator. At 1,000 RPM I get about 20 VAC phase to phase and it increases 20 V / 1,000 RPM just like it should. The manufacturer sells only the full kit so I get a brand new stator and rotor I don't need and the regulator which I really need. A tiny little silver box which takes 5 min to swap out. So I bought the system. This was almost a year ago.
So a few says ago I am out for a ride and turn signals quit working so here comes that sinking feeling as I look at the voltmeter. It was erratic but did return to about 13.6 volts. This is exactly like deja vue all over again. I called JP Cycle and they were no problem and gave me a link to a return UPS label, I figured I was screwed but nope so in a week or so I should have another new kit. I returned the brand new rotor and stator from last year still in the packaging. This setup is a 38 amp charging system.
Then I started thinking about these regulators and as can be seen there isn't much to them. A three phase rectifier 100V 50A isn't much then I thought rather than a 555 for PWM and a IRF540 I could use an IRL540 N Channel Mosfet and drive it using a uC like an Arduino which I have a few chip only with sockets, Maybe use a 10 turn 100K pot as a divider into an analog input and generate a PWM out to drive my uC. Analog in and PWM out. The IRL 540 should hack the shunting duty. Can anyone think of why this approach won't work? Really not much to it and thought I would kick it around for something to do. I think I came in just under the wire on that exchange.
Ron