Regulating a high current source using arduino mega

Hello Everyone,

have a current source (0-3A) for a solenoid and Arduino Mega. I want to regulate the current using Arduino mega. Please help.

Vyom

vyom:
Hello Everyone,

have a current source (0-3A) for a solenoid and Arduino Mega. I want to regulate the current using Arduino mega. Please help.

Vyom

What do you mean regulate current ? Do you want to be able to measure and vary the current that is being provided to your solenoid ?

Craig

Normally for analog regulation you would need a low-pass filter to convert PWM to an analog voltage,
then an op-amp in voltage-controller current-source mode (with a transistor on the output to boost the
current).

Since solenoids usually have soft-iron cores (rather than laminated silicon steel) direct PWM to the
solenoid coil isn't going to work well as there will be a lot of iron-losses due to large eddy-currents.
However without knowing the application its hard to say how important eddy current losses are
(if the device is continuously on they could easily cause overheating for instance).

@Craig
I have a current source which provides max current of 3A. The current is increased manually by rotating a knob on the instrument . My goal is to perform this increment in current by arduino and in a very uniform manner. In short the manual rotation be replaced by some automatic control (of arduino). That was what I meant by regulation.

@MarkT

Yes, I got almost the same idea from many tutorials. But issue is which components I should use. Let me remind you that I have a current source, Not a voltage source. So I cannot connect it directly to transistor (I am thinking of using a TIP142 or may be a power mosfet) to get excess current.