requires the direction of current to be changed, without the

[hamish888]

Hi guys,

Im a mechanical design engineer and have an electronic system to design. Part of its operation requires the direction of current to be changed, without the use of relays.

It has been a long time since I had electronics classes at university and am slightly out of my depth with this . Is it possible? 8O

 

[banjo]

Help!

Changing the direction of current requires that you change the polarity of the driving voltage.

Changing this voltage polarity may be easy or hard depending on the load that is attached an the magnitude of the current required.

Typically, for smaller currents this is accomplished with a power opamp. The opamp is run from a dual power supply with both positive and negative inputs.

 

[hamish888]

Re: requires the direction of current to be changed, without

I plan to use this within a low power logic curcuit control system leading to a high power curcuit. The input current to the op amp would be 100ma

How can I use the inverting and non inverting inputs on the op amp to reverse the voltage polarity?

The high power curcuit is to be used to power two electric motors at 24v, max 10.4a and 250w

From the low power curcuit is the best way to link to the high power curcuit (provided I can use the op amp)?

 

[hock]

Re: requires the direction of current to be changed, without

use a full bridge mosfet ckt.
if you turn one transistor in top arm and other in diagonal arm current will flow in the load in one dir. switch the other two devises and the current will flow in reverse direction. refer to any power electronic book and see the invertor section.

hock