The widespread deployment of power electronic devices in the grid has underscored the importance of real-time simulation. However, conventional L/C-based associated discrete circuit (L/C-ADC) model used for converter-level real-time simulation suffers from virtual power losses, thus limiting its applicability in high-frequency and large time step conditions. To address this issue, this article proposes an improved L/C-ADC modeling method based on historical current source reconstruction, termed as reconstruction-based ADC (R-ADC) model. By leveraging the smoothly varying electrical quantities associated with the converter’s energy storage components, the method reconstructs the switch’s historical current source at each switching event, ensuring immediate posttransition steady-state behavior and effectively minimizing virtual power losses. This reconstruction method is applicable to both pulse-blocked and pulse-deblocked statuses and is validated on a hardware-in-the-loop (HIL) platform. Results demonstrate that the method effectively suppresses waveform spikes and virtual power losses, outperforming conventional L/C-ADC models as well as other ADC-based models proposed in the literature. Evaluations over a range of carrier frequencies and practically admissible time steps confirm weak sensitivity of its virtual loss level to carrier frequency and time step. Furthermore, its adaptability to large time steps up to 40 s is also demonstrated through the application in a photovoltaic grid-connected system.