Why PH value cannot be controlled？

Problem：PH value cannot be controlled

PID setting： ?That is right.

Reason：Compared with alkaline solution, the buffering capacity of fermentation broth is too low.

Solution: ?Pls kindly use Ti: 0 Td:0

That is to say, the PID control is changed to only the proportional control method. In this case, it is the most intuitive control method. That is, if the pH is high, add acid, and if it is low, add alkali.

In addition, the buffering capacity of the configured alkali solution and fermentation broth is inconsistent. For example, the original requirement is almost 1000 times, that is, adding 1mL of alkali solution can change the pH of 1L fermentation tank liquid to 0.2pH. In this case , it can be guaranteed that even if excessive alkali is added, the pH change will not exceed 0.2; If the multiple is 10,000 times, that is, an amplification of 10 times, then 1 mL will cause the pH to rise by 2.0, which is a problem.