Based on the nonlinear relationship between the voltage and current of the DC link

a piecewise affine model(PWA)of voltage source converter based high-voltage direct-current(VSC-HVDC)system is developed. According to the characteristics of fast dynamic change of PWA system with state and input constraints

this paper makes up for the shortcomings of model predictive control(MPC)causing slowed-down system response and degraded real-time performance. Explicit model predictive control(EMPC)combined with off-line calculation and on-line analysis is used to transform repeated online rolling optimization calculation into a simple table lookup process. The output trajectory of the VSC-HVDC system by means of expected interval tracking deviation and adding the variable soft constraints is optimized. Simulation results show that the explicit model predictive controller has good dynamic performance and steady performance

while able to suppress fluctuations of output trajectory. Compared with the MPC

the dynamic response of EMPC is faster

and the real-time of EMPC is stronger.