controller for single phase bldc motor

Hi all,

Here i have attached the controller circuit schematics(done in LTSpice) for single phase BLDC motor. The basic working is that based on the hall sensor signal, the current output of H bridge inverter should reverse. Across points A & B we'll be connecting the motor. Here the pulse signal represents the hall sensor output signal. The problem with this circuit is that when load (50 ohm) is connected across A & B, the required voltage and current signals are not getting. The voltage signal should be a square wave of 72 Vp-p (Vmax=36V) but what i am getting is a 4.8Vp-p square wave.Also, output of zener diode shold be 36V but 5V is the output with load.Without load its working fine. What could be the reason? Any suggestions to improve the circuit?

Hi,

R11, R12, R13 limit the current to an almost useless value.

Klaus

R11, R12, R13 limit the current to an almost useless value.

Click to expand...

Not particularly. Obviously C1 is intended to deliver the relevant current (about 70 mA).

A brief calculation clarifies that the motor consumes the tenfold current. On the other hand, D1 will already burn at 10 mA or so. The circuit doesn't seem to be well considered in any regard.

My suggestion: Open trash bin, put schematic in, close trash bin. Or think about a regular transformer or switch mode power supply.