Hi, im new to this but have taken on the task to control an TRW electric stering pump with the arduino. Iwe stripped down the components as the motherbord from this and are now left with what i can se is an 4 wire BLDC motor. This has 4 BUK9E06 transistors controlling each wire. This is an 12V system. Is it as simple as hook up each transistor to 4 different PWM on the arduino? Do i need resistors between PWM pin and transistors? Can mayby sombody scetch wiring diagram for me pleese?
BLDC motors require a sophisticated driver circuit and control. If you never have been controlling motors, start with a DC motor, then a stepper motor, so that subsequently you can understand how to drive a BLDC motor.
The rest is easy if a BLDC motor has hall sensors built in, near impossible to manage without such sensors.
The OP destroyed any reasonable chance of success when he removed all of the exsisting circuitry before having observed operation of the original system, noting important attributes like operating currents and PWM characteristics. If the OP removed the the old control system because it had failed, it’s highly likely one or more of those remaining mosfets is defective since the power devices are much more likely to fail than the control circuits.
The harsh reality is that without an identical system to reverse engineer the system details and the necessary method of control, chances of any success are extremely slim to none.