Based on the analysis of the plasma physics mechanism in negative hydrogen ion source,the particle-in-cell algorithm is studied and optimized and a high efficient storage method of particles is designed.Using the Monte Carlo collision model,considering the plasma potential and coulomb collisions between charged particles,the full three-dimensional particle-in-cell/ Monte Carlo algorithm (PIC/MCC) is developed.With the magnetic charge model,using the FDTD method,the line cusp magnetic field is calculated.Wit...