Novel optimized arithmetic for distributed pumped ytterbium-doped double-clad fiber amplifier

The time independent rate equations for fiber amplifier were solved by average inversion ratio iteration method. In this paper, a novel arithmetic based on genetic algorithm was proposed to optimize the distributed pump powers and the lengths of fiber segments in kilowatt YDDC fiber amplifier. The standard deviation of maximum temperatures in fiber segments was incorporated into evaluation function. This ensured that the maximum temperature in each fiber segment was identical. Based on the genetic algorithm method, the maximum temperature and standard deviation of maximum temperatures in seven-segment scheme were 126.34 ℃ and 1.95 ℃，compared to 147.12 ℃ and 21.37 ℃ without the optimization process. To eight-segment scheme, the optimized results were 119.76 ℃ and 2.12 ℃. The calculat