STATCOM Simulation with Carrier Phase Shift and PI Controller (Current Feedforward Decoupling)

To achieve balanced DC-side voltage control, we implemented a Static Synchronous Compensator (STATCOM) simulation system using carrier phase shift modulation and PI controllers with current feedforward decoupling. The simulation employs a cascaded H-bridge circuit topology, where carrier phase shift techniques control the current waveforms while PI regulators handle the feedforward decoupling mechanism. This innovative control scheme enables precise voltage balancing through proper phase distribution among H-bridge modules and incorporates feedforward compensation to decouple active and reactive current components. The implementation typically involves generating phase-shifted triangular carriers for each H-bridge module, calculating current references based on voltage balancing requirements, and applying PI controllers with decoupling terms in the dq-reference frame. This approach significantly enhances system performance and stability by maintaining capacitor voltage equilibrium across all cascaded units while ensuring fast dynamic response.