A DC source is connected to a load consisting of an AC voltage source uLoad and an inductor. The blue box symbolizes a converter, for example the one in the previous applet 'Hysteresis Control / Switching Frequency Variation'. The load side voltage of the converter is modeled as a fundamental sinusoidal voltage u2,(1) and some high-frequency harmonics u2,(n). Converter output voltage u2, which is pulse shaped, is shown on the upper time-domain plot. The difference between the fundamental u2,(1) of u2 and the AC voltage uLoad (blue) is a voltage drop on the inductor, which defines the load current i2. Current i2 is shown in the diagram below. See also the applet 'AC-Side Current Ripple'. Below the topology the phasor diagram is shown for the fundamentals of AC voltage uLoad, converter output voltage u2,(1), inductor voltage uL(1) and output current i2(1).

• Drag the red point of the voltage curve u2,(1) in a (small) circle around the red point of AC voltage uLoad. You can see in the time behaviour diagram, but especially in the phasor diagram, how small changes between the two voltages define the current i2.
• If u2,(1) is close to the maximum voltage U1, the valid area of uL(1) (green) is limited by the circle of U1. Accordingly, there are restrictions to the operating range of the converter system.