Is is possible to control the speed of an induction motor (single or three phase) by reducing the voltage. This will reduce the magnetizing current, flux, and thereby increase the slip, by essentially reducing the rating. Not all types of motors are designed to run with significant slip (e.g. more than 5%).
How do you reduce motor speed?
So, if you want to decrease speed, decrease voltage. If you want to decrease torque, decrease current. If you increase torque (say by putting a brake on the motor), you are increasing motor torque. But if you don’t change the supply of electrical power, then the mechanical power also won’t change.
How does current affect motor speed?
The current through the motor times the resistance of the motor creates a small voltage that must be subtracted from the applied voltage. As the load and current increase, this IR drop also increases causing the motor to lose a little speed.
How can a motor spin fast?
One easy way to make the motor run faster is to add another magnet. Hold a magnet over the top of the motor while it is running. As you move the magnet closer to the spinning coil, one of two things will happen. Either the motor will stop, or it will run faster.
Is used to control the motor speed?
Well many people attempt to control the speed of a DC motor using a large variable resistor (Rheostat) in series with the motor as shown. … One simple and easy way to control the speed of a motor is to regulate the amount of voltage across its terminals and this can be achieved using “Pulse Width Modulation” or PWM.
How do Motors change speed?
AC motors are constant speed devices but their speed can vary if you change the input voltage or frequency or the windings that make the motor rotate. The most common and efficient way of changing the speed is to vary the frequency by using an inverter as the power supply.
Which motor is best for speed control?
Brushless DC motors are an advanced option due to their wide speed range, low heat and maintenance-free operation. Stepper Motors offer high torque and smooth low speed operation. Speed is typically controlled by manual operation on the driver or by an external switch, or with an external 0~10 VDC.
How do gears reduce speed?
The basic gear changing rule is ‘brakes to slow – gears to go’. As the car increases speed, change up through the gears. When you want to slow down, use the foot brake. You need only change to a lower gear when you need the accelerator again to ‘drive’ the car.