Setting Tools Motor

In an exciting project, iNetic was tasked with designing a BLDC motor capable of operating in high-temperature environments for setting tool applications. This case study highlights our engineering excellence in meeting stringent requirements and delivering a reliable solution.

Setting Tools Motor

Technical Specifications

Input:

• DC Bus Voltage: 600 V (maximum)
• Current: 1.8 A (maximum)

Environment:

• Ambient Temperature: -20°C to +175°C
• Pressure: 27000 PSI

The motor operates submerged in MOBIL SHC 524 hydraulic oil or equivalent.

Mechanical Interface:

• Stator Diameter: 60 mm
• Housing Length: 170 mm

The stator’s total length includes the stator, end windings, and Hall Sensor. The rotor is designed to be as short as possible, with bearings mounted on both sides and featuring a male spline at the lower end. The stator has an anti-rotation feature for locking to the housing.

Features:

• Hall Sensor: Fitted with a 3.3VDC supply voltage
• Temperature Sensor: PT1000 embedded in the windings, accessible from the same side as the Hall Sensor
• Motor Design: 3 pole pairs motor

Wiring:

• Motor Phase Wires: Red, Blue, Yellow (22 AWG)
• Hall Sensor Wires: Green, Orange, White, Red, Black (26 AWG)
• PT1000 Sensor Wires: white & black (26 AWG)

All wires are twisted together and attached with flying leads style, with a length of at least 500mm.

Performance:

• At 140°C Ambient Temperature:
  • Torque: 2.4Nm (minimum)
  • Speed Range: 400 to 4000 rpm
• At 175°C Ambient Temperature:
  • Torque: 2.0 Nm (minimum)
  • Speed Range: 400 to 4000 rpm

The motor delivers 2.4 Nm torque up to 40% of the maximum speed (2000 rpm). Beyond 2000 rpm, the available torque is reduced, but at 5000 rpm, it produces more than 0.8 Nm. The temperature increases of the windings at maximum torque (2.4 Nm) and 140°C remain below 210°C after continuous operation.

Lifespan:

• Expected Lifespan: 500 hours, assuming the following duty cycle:
  • Duty cycle of 10/80/10: 10% at 0.9 Nm torque, 80% > 1.7 Nm, 10% at maximum allowed torque
  • Duty cycle of 30/60/10: 30% at 0.9 Nm torque, 60% > 1.7 Nm, 10% at maximum allowed torque
  • Duty cycle of 40/50/10: 40% at 0.9 Nm torque, 50% > 1.7 Nm, 10% at maximum allowed torque

Verification

The motor undergoes different testing by iNetic prior to delivery, ensuring it meets the specified performance parameters:

1. Ability to spin at 5000 rpm or higher.
2. No load testing and wave form analysis
3. Load testing to prove the ability to generate 2.6 Nm up to 2000 rpm at an ambient temperature of 140°C.
4. Running continuously at 175°C ambient temperature with 50% of maximum torque (1.3 Nm).