In this paper, characteristics of the digital computer control of temperature in a growth-cabinet were made clear by simulation. Simulation of temperature control system on modelling of a growth-cabinet was carried out by means of hybrid computer. Sampling PID control was carried out by means of digital computer.
Characteristics of K, TI and TD were examined with τ-parameter in the simulation.
1) Value of K should be decided upon the relations with manipulating capacity P or τ. Computer control of temperature should be programmed in consideration of proper value of K in steady-state condition or in transient condition.
2) Value of TI should be smaller in steady-state condition than in transient condition.
3) Value of TD should be small in either case.
4) Stability of temperature control is better in smaller τ, though it is good in larger τ (τ=20 sec.) on the condition of optimum K, TI and TD from the data of simulation.
5) Time constant of detecting means should be examined in consideration of P and K.