Brushless DC Motor

CLIENT

Client is a North India based company working in the field of Electric Vehicles.

OBJECTIVE

• To develop the controller for Hall sensor based BLDC (Brushless DC) motor having following features:-
• Controller should take a payload of 20Nm.
• Provide a current limiting action which can be varied depending on necessity.
• Maximum motor speed - 25km/hr.
• Soft - Start for motor
• Brake Logic, Reserve Feature, Temperature Protection, Overcurrent Shutdown  

PROJECT SCOPE

The System should provide current limiting action using standard control techniques like PI. Analog signals like temperature, battery voltage and Overcurrent condition need to be monitored to provide protection feature.

KRITIKAL’S ROLE

KritiKal was solely responsible to bring the product to completion from the inception stage. The project demanded expertise in designing and developing ‘Embedded C’ applications with good understanding of Control System concepts like PI control, Feedback etc. The client required a team, which could handle full controller development and also provide ample support during ARAI approval,

CHALLENGES

• Control Systems Knowledge: A thorough understanding of control systems was required by the development team for successful implementation of features like PI control of current, hysteresis etc.
• Drive Circuit and basic BLDC motor knowledge: The project required expertise in Drive circuitry and knowledge of different states changes of the BLDC motor-in-motion.
• Continuously evolving requirements: Project requirements kept evolving throughout the project life cycle as per features required by the end user.
• Time constraint: The timeline for this project was a major challenge as there was a short & stringent deadline for submitting a working prototype for ARAI (Automotive Research Association of India (ARAI) approval purpose.  

VALUE DELIVERED

This controller is the first indigenously developed controller for BLDC motor in the market. Client has obtained the ARAI acceptance for the controller and 6000km of road test has been concluded. The controller has been put in production mode since October 2009.