In this paper, on the basis of nonequilibrium thermodynamics separation theory, the separation model of capillary electrophoresis is established. Taking the operating voltage U as controllable parameter, the net separation entropy S~S of solute system as objective function, by optimal design of the separation big system, the optimizing control orbit U^*(t) can be obtained. By simulation, the separation efficiency of the system under the control of U^*(t) can reach to the expected results.

Key words: THERMODYNAMICAL MODEL, SEPARATION EFFICIENCY