Variable Voltage Regulator vs MOSFET PWM for 15V DC Motor Speed Control After Rectifier

Hello

I am currently making a bridge rectifier to convert AC to DC and connect the output to a motor, however, I need a circuit after the bridge rectifier to control the speed of a 15V DC motor. I am getting 19V output from the AC to DC converter.  I need two approaches to control the speed of the motor 

1. Using a variable voltage regulator.

2. Using a MOSFET switched supply.

attached is a multisim simulation picture of the AC TO DC converter.

but I still need the motor control circuit.

 

Thanks

 

 

simulation pictur

You probably want a PWM controller if you want high efficiency and decent low speed motor torque. If you provide the current requirements for the motor someone here can probably find one for you.

Using a variable voltage regulator (assuming it is a linear regulator/LDO) will be inefficient and generate a lot of heat. It will also provide very poor torque at low motor speeds.

Using a MOSFET switched supply will deal with the efficiency problem, but has to be carefully designed to handle the back EMF from the motor and does not address the low speed torque issue.

Thank you for the reply

I am looking at a current of between 0.143A and 0.758

Thanks

Take a look at:
https://www.picotech.com/library/application-...some-power-pwm-drivers-for-electric-dc-motors

At under 1 amp, pretty much any power nfet will work in the circuits.

You can also use integrated brushed motor drivers, take a look at TI, Allegro Micro, ST, etc. These will provide over-current protection, reversible rotation (full bridge drivers) and other benefits. At under 1 amp there are lots of options with built-in fets resulting in a single-chip solution.

ST has a bunch of cheap NUCLEO boards with DC brushed motor drivers (they are in the arduino shield form factor so you can use them with the ST ARM nucleo boards or any of the 8 or 322 bit arduino boards).

http://www.mouser.com/_/?Keyword=NUCLEO+dc+motor&FS=True