Synchro-to-Digital Converter

Google synchro resolver digital and start trawling through the dozens of possibilities.

I have used the older versions of North Atlantic APIs, mechanical and electronic.

Resolvers too.

DDC and Aeroflex make S/D's

You can track back the phase angle measurement to a simple time ratio measurement. The time (t) between the -/+ transition of the reference voltage and the -/+ transition of the rotor output voltage will be linearly proportional with the phase angle. You only have to know the exact period (T). If you have a simple PIC you can write a very simple program in order to evaluate the T and t and convert the ratio to degrees or radians.

You only need a PIC with two analogue inputs and a counter. Either analogue input is connected to the reference voltage, the other one is to the rotor output. The program of the PIC is the following one:

1. Find the first -/+ transition of the reference voltage

2. Start the counter

3. Find the -/+ transition of the rotor voltage

4. Store the counter value (t_d)

5. Find the next -/+ transition of the reference voltage

6. Store the counter value (T_p)

7. Divide t_d with T_p and multiple the result with 360: That will be α, the phase angle in degrees.

8. Display α

9. go to step 1.

The accuracy depends on the counter frequency and the accuracy of the analogue inputs.

this solution can't be used as angle detector.

synchro devices modulate refrence signal in AM mode,all S1,S2,S3 signal have same frequency with phase 0/180.

some thing like Average and magnitude detection with mathematical solve must be used as in MCS usage sysem.