I have an electric power steering pump out of a 2005 50 series Volvo. It is can bus controlled. I have installed it in a project and have it running, but only at a low rpm. It is a TRW pump, with a brushless dc motor with 4 windings. The speed of the motor is controlled by the control module using PWM. A hall sensor in the motor informs the control module of the actual speed. The rpm range is between 1300 and 4500 rpm, it is running at the lower rpm range and does not provide enough assist.. Is there a controller available that I could use to bypass the can controll? What about altering the hall signal to trick the module? Any ideas are welcome

 

I'm afraid you have to re-engineer the drive controller, or figure out the CAN bus commands you need to send to the controller. What makes you think that Volvo wants to make this easy for you?

 

I would install it back in the car and use a canbus sniffer to see what commands the car is sending to it through out the whole rpm range. Then send it those same commands.

 

Are you sure there is not more than one Hall sensor for commutation?
Max.

 

Are you sure there is not more than one Hall sensor for commutation?
Max.

A single hall circuit and 4 windings