Process Engineering Division – Instrumentation and Automation Section – Daily Topics – Topic No. 2021-01-08
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Process Engineering Division – Instrumentation and Automation Section – Daily Topics – Topic No. 2021-01-08: Discussion question: 351. What control law can be used when the load changes are small and no error requirements are specified in the process? (Extra points for a reasonable analysis)
When the load variation is small and no error requirements are specified in the process, a proportional control law can be used
What control law can be used when the load variation is small and no error requirements are specified in the process? Answer: When the load variation is small and no error requirements are specified in the process, a proportional control law can be used. Since proportional control (P) is a type of continuous control and represents the most fundamental control law: the proportional control law states that the relationship between the controller’s output P and its input error e is proportional. The adjustment action is rapid, with no lag ； After the regulation process is complete, a certain residual error remains, which is a drawback of proportional control ； The value of Kc must be appropriate; otherwise, it may cause oscillations in the system or an increase in the residual error. Suitable for situations where some deviation is allowed and the quality requirements are not high. It is suitable for applications without lag, that is, for situations where fast response times are required.
When the load variation is small and no error requirements are specified in the process, a proportional control law can be used
Proportional adjustment is sufficient; P=200 is about right
P-control will result in certain residuals; there are no requirements regarding deviations in terms of process parameters, and the load variations are not significant either, so P-control is sufficient.
A proportional control law can be used. Since proportional control (P) is a type of continuous control and represents the most fundamental control law: the proportional control law states that the relationship between the controller’s output P and its input error e is proportional. The adjustment action is rapid, with no lag ； After the regulation process is complete, a certain residual error remains, which is a drawback of proportional control ； The value of Kc must be appropriate; otherwise, it may cause oscillations in the system or an increase in the residual error. Suitable for situations where some deviation is allowed and the quality requirements are not high. It is suitable for applications without lag, that is, for situations where fast response times are required.
A pure proportional control law can be used.