MATLAB Simulation of HVDC Light Continuous-Time State-Space Model

HVDC Light is a flexible HVDC transmission system based on Voltage Source Converter (VSC) technology, widely applied in renewable energy integration and grid interconnection. Establishing its continuous-time state-space model and performing MATLAB simulation serves as an effective approach for analyzing system dynamic characteristics.

For modeling HVDC Light systems, it is essential to consider converter dynamics, DC-side capacitors, and AC-side filtering components. The state-space model represents the system through a set of differential equations, clearly describing dynamic relationships among various state variables. Continuous-time models more closely resemble actual physical system behavior by avoiding errors introduced through discretization.

When implementing this simulation in MATLAB, the first step involves deriving system state equations based on circuit theory. Typically, a dq-frame model is employed to convert three-phase AC quantities into DC components for simplified processing. The implementation then utilizes ODE solvers (such as ode45) for numerical solution of state equations to obtain system time-domain responses. During simulation, dynamic processes of key variables like DC voltage and AC currents can be observed through plotting functions like plot() or scope blocks in Simulink.

This simulation approach is particularly suitable for investigating control strategies and small-signal stability of HVDC Light systems. By adjusting control parameters through parametric sweeps, system dynamic performance can be optimized. Furthermore, the state-space model provides a theoretical foundation for subsequent designs such as state feedback controllers using methods like pole placement or LQR optimization.