CASE STUDY

Prototype BLDC controller for diesel exhaust aftertreatment system

Summary

The objective of this customer-confidential development project was to design and test a proof-of-concept sensor-less Brushless Direct Current (BLDC) motor controller for Urea dosing pumps used in medium duty commercial vehicle diesel exhaust aftertreatment systems.

Challenge

Pi Innovo’s challenge was to develop a hardware and software solution to support rapid prototyping and subsequent ongoing development of a control system for new design Urea dosing systems utilizing a common controller design to operate both 12V and 24V brushless motor driven pumps.

Solution

Pi Innovo designed and developed a custom daughter board for its M250 OpenECU product to drive BLDC motors and developed platform-level and application software to drive and control the target motor.

The platform software incorporating signal windowing for control based on the back-EMF recommended by the motor manufacturer was developed in conjunction with the daughter card providing signal conditioning circuitry and functionally tested on a Hardware-In-Loop (HIL) test rigs utilizing the sensor-less BLDC motor specified for this system. Once the platform software was proven, the application software was developed to control the motor as part of a new Urea dosing system being developed for Medium Duty commercial vehicle diesel exhaust aftertreatment.

The overall aim for this development project was to integrate the proof-of-concept BLDC motor controller design into a custom aftertreatment control ECU to be introduced into volume production for 12V and 24V systems.

Project Features

OpenECU rapid controls prototyping

Custom signal conditioning daughter card design

Software platform development

Sensorless BLDC controller design

Duration

6 months, December 2010 to June 2011