I want to run a 4 phase switched reluctance motor at low speed. The expected conduction sequence for the motor winding(y, r, b, g) follows the output similar to that of a 4-bit ring counter and thus I want to use a ring counter to give gate pulses to the power circuit of the motor.
The problem is with the clock. I want to be able to generate the clock from the outputs of two optical sensors in motors rotors. The following picture explains what exactly I want to achieve.
So, using the two sensor outputs, Q1 & Q2, I want to make a clock as shown in the clock waveform, which I will feed to my 4-bit ring counter to generate the 4 expected phase currents, Iy, Ir, Ib, Ig. (As can be seen, these expected phase currents follow the output of a 4-bit ring counter). Thus, will be able to run my motor at low speeds like 60/120/180 RPM.
How to generate the "clock" for the 4 bit Ring counter from the sensor outputs(Q1 & Q2) as shown in the figure above?
The clock will be positive edge triggered to the counter. Also, as the sensor output(effect) is generated as the motor rotates(cause) , initially I plan onto give a manual start to the motor via some extra circuitry and then as the motor attains some low speed, the external circuitry can be automatically disconnected and the counter circuit (using sensor outputs) will be used to run the motor.
Also, suggestions on some other different methods to run the motor are also welcome.