solenoid powered by pulsed current

[luckym]

Hello.

If the solenoid is powered by DC current this current invokes a magnetic force. But if the solenoid is powered by pulsed supply (PWM), which current is equivalent to the DC current (The pulsed current should invoke the same magnetic force)? Measured between solenoid and reverse diode or supply current? It is average or rms value?

thanks for explanation.

 

[jamshid.dastur]

Hello, well a solenoid is driven by drawing a huge amount of current, so when you're connecting it to a constant dc source it draws the ammount of current required to energise and produce the electromagnetic field...so now even if you connect it to the pulsed signal though to energise it will draw the same amount of current, now it depends weather the delay is enough to allow the amount of current to flow...in short if the pulse is large the current drawn will be equivalent to the current being drawn when connect to a constant DC current source, hence generating an equivalent magnetic field...but if the delays short then the generation will not be much.
Best Regards

 

[luckym]

Thanks for reply.
OK, I understand this. But the thing I want to know is where to insert the shunt resistor for current measurement. According to the 1st or 2nd pict.? On the picture 1. the measured current include reverse current. Does the reverse current contribute tu emg. field and should be included in the measurement?

thanks