PI Gain Tuning with PSO

I'm using PSO for PI gain tunning. the algorithm works well for synchronous machine but for asynchronous machine the pso algorithm is giving this error

variable "Particle" doesnot exit but as u can see in the code the particle is already define

particle = 1:swarmsize

[Neelanshu]

Kindly attach your Simulink model to help resolve the issue effectively.