Slow down dc motor

If not only slowing down , but also variable speed is require it is best to select gearing for the proper maximum speed and then use electronic control to provide variation. Larger DC motors are seldom used for fixed speed operation, but electronic control or series resistance may be required just for . Use some sort of physical restriction to slow it down (i.e. weights). You need to completely redo this.

If motor induction type, control needs be inverter drive (like VFD).

If motor brush and com type control can be rheostat which means variable resistor but way inefficient!

Should use pwm or phase control!

Slow as 3rpm means gearmotor or sophisticated driver for dc motor. If you have diodes that can handle the current, you can put them in series till you get down to the voltage you want. Instea you pulse-width-modulate the 12V power source to slow the motor down. The experience of using this type of motors showed that they are highly . By changing the pulse width or duty cycle of the PWM signal, the amplitude of the average voltage can be controlled. This will in turn speed up or slow down the motor.

The advantage of Pulse Width modulation is that the motor slows down without losing any power since the voltage supplied to the motor is not reduced. Your typical household 9V batteries are notorious for their very high internal resistance. PWM is better and they make controllers.

The driving forces would cease to act on the armature conductors, and the mechanical drag imposed by the fan and the bearings would immediately cause the motor to slow down. The speed will cease to fall as soon as . Need more control of your DC motor ? The higher the voltage, the high the speed. Conversely, lowering the voltage slows things down.

Motor production: Spee Torque and Horsepower - Duration: 4:48. Abstract—This design uses Proteus software to design and simulate for the DC motor PWM speed regulator and get the main control of the motor. This article is designed primarily to achieve DC motor PWM governor of forwar reverse, speed up, slow down , stop and other operations. And it also includes simulation of the .