Projects / Electrical / Electrical project 14

Soft Starter for a Single-Phase Induction Motor using Phase Control

Approx. component budget: Rs. 5,000 - 9,000

Objective

Reduce the starting current of a motor by ramping the voltage and compare it with direct-on-line starting.

What you will build

A TRIAC or back-to-back thyristor circuit with zero-cross detection, a microcontroller ramping the firing angle, a bypass relay and current measurement.

Results you can expect

• Starting current vs time for DOL and soft start
• Ramp time effect
• Torque during start
• Heating of the motor and TRIAC

What you will learn

Motor starting methods, phase control and zero-cross detection, used in pumps and conveyors.

Tools and notes

Arduino, optocoupler with zero-cross detection, TRIAC with heat sink, oscilloscope or current logger. Works at mains voltage, so use a full enclosure, isolation and a fuse. Work only with supervision.

Resume points from this project

• Built and tested Soft Starter for a Single-Phase Induction Motor using Phase Control; objective: reduce the starting current of a motor by ramping the voltage and compare it with direct-on-line starting.
• Measured and analysed starting current vs time for DOL and soft start and ramp time effect; wrote the report and presented the results in a viva. Add your own numbers: [x].

Replace [x] with your own measured results. Write only what you really did.

More electrical projects

Back to all projects