Development of “Four phase dual coil stepper motor with resolver (feedback)”

India is still dependent on countries like France, Germany and US for the supply of stepper motors for the use in fuel metering system.

Currently there is no firm in India which has developed an airworthy stepper motor for the above said use.

The specification and qualification requirement of the component is specified below.

• Type: Hybrid stepper motor
• Voltage: 28V DC(Nominal), varying from 14 to 32 V
• Constant current control: 1 A ± 10mA
• Stepping Angle: 0.5°/1° (Half step / Full step)
• Dynamic torque: 15 Oz-in (1080 gm-cm) min.
• Temperature range: -40 °C to +70 °C
• Maximum stepping rate: 500 Steps /sec
• Medium of cooling: Air cooling
• Number of phases: 4 Phases (A, B, C & D)
• Resolver Supply: 5.5 to 10 VAC, 2500± 250 Hz
• Coil type: Dual coil type
• Winding insulation: Class H
• No. of Phase leads: 6
• Phase Lead requirement: MIL-STD; 6 pin for each channel of stepper motor and for resolver.

Future Expectation from the prototype / Technology developed

The stepper motor so developed will be used on many of the engines that are being developed at AERDC-HAL.