Learning Forum

[p43kumar]

The system studied here is a 2 coil setup embedded within a pure iron core (fig. 1). The setup can be treated like an Resistor and inductor system. A capacitor is added in parallel to reduce the impedance experienced by the system (fig. 2). A voltage source of 300 V at 1000 Hz is suppling the input to the system. By having a capacitor in parallel, there is a significant voltage drop experienced. The plot of the voltage reduction is shown in the fig. 3. The simulation was also ran for 200 ms with a 100 mF capacitor in parallel to ensure that steady state was achieved, as shown in fig. 4. I was wondering if someone could help me understand why this voltage drop occurs? 

[rmagargl]

Typically if you are lowering the shunt impedance, and with some types of resonance, the result will be increased supply current flow for the same voltage. Check the voltage drop on your supply resistor, R1, and see if the voltage drop there has increased there due to the increased current from your lowered AC impedance, if so this will reduce the voltage left for your load. If VM1.V and R1.V add up to the source voltage that explains where the voltage went as you increased your capacitance shunt.nAlso, you should place a ground in the circuit so it has a stable reference for the voltage measurements.n