Thanks For the suggestion..
I did experiment with small value of burden resistor(15ohm) and 470k input resistor for transformer.
Output voltage amplitude got reduced to 7mili volts rms.
And phase angle difference between input and output waveform is around 6degree.
I can use the internal programmable gain amplifier of ADC to amplify 7 mv signal to acceptable value.
Phase angle difference also looks reasonable.
I need to test the ckt with connecting to microcontroller and at different input voltages.
Mean while i will try out the other suggestions and check results.
Can i get some reference of
transformer with two secondary windings, or a tapped secondary.
More details about implemention of a zero flux circuit with separate source and sense to eliminates the winding resistance effect.
I can share this details with my transformer vendors.