Document Type : Research Paper


Electrical Engineering Dept., University of Technology-Iraq, Alsina’a street, 10066 Baghdad, Iraq.


This paper presents an algorithm to solve the unit commitment problem using the intelligence technique based on improved Particle Swarm Optimization (IPSO) for establishing the optimal scheduling of the generating units in the electric power system with the lowest production cost during a specified time and subjected to all the constraints. The minimum production cost is calculated based on using the Lambda Iteration method. A conventional method was also used for solving the unit commitment problem using the Dynamic Programming method (DP). The two methods were tested on the 14-bus IEEE test system and the results of both methods were compared with each other and with other references. The comparison showed the effectiveness of the proposed method over other methods.


  • The optimal scheduling of power generation
  • The Unit Commitment Solution based on Improved Particle Swarm Optimization.
  • lowest production cost during a specified period of time.
  • Economic Dispatch solution with Lambda Iteration Method.
  • Dynamic Programming a conventional method used for solving the unit commitment.


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