I am trying to impose an AC ripple of 0.9V peak to peak (1kHz) on 36 volts DC supply for one of the test using following circuit.
Without any load connected, I get the proper AC imposed DC voltage but as soon as I connect a resistive or capcitive load to the output, the AC ripple of 0.9V just vanishes. Only 36 volts is left behind. The AC current source is capable of sourcing 400mA which is much higher than my actual current requirement of 280mA DC input current of load.
What could be the reason of vanishing of AC ripple when the load is connected ?
Do I need to use higher current sourcing AC source?
Does the value of the coupling capacitor need to be increased to reduce the output the impedance?
Any other means to achieve the functionality are also welcome!!