In the field of control system electrical, there are many types of control systems, mainly including open-loop control systems and closed-loop control systems (also called feedback control systems). These two systems play an important role in electrical control and have different working principles, structural compositions, stability and control effects.
1. Open-loop control system electrical
Definition: Open-loop control system electrical refers to an electrical control system in which there is only a forward action but no reverse connection between the control device and the controlled object. That is, the output of the system has no effect on the control action, and there is a clear correspondence between the input and output, but there is no feedback mechanism.
Features:
* The structure is relatively simple, mainly composed of a control device and a controlled object.
* The control accuracy mainly depends on the components used in the system and the accuracy of the calibration.
* It is sensitive to changes in system parameters, and the control accuracy and interference suppression performance are relatively poor.
Application example: The washing process of a semi-automatic or fully automatic washing machine can be regarded as an application example of an open-loop control system electrical. The user sets the washing and rinsing time according to the degree of dirtiness of the clothes, and the washing machine completes the washing and rinsing tasks according to the set program, but the system does not detect the cleanliness of the clothes and adjust the washing time accordingly.
2. Closed-loop control system electrical
Definition: Closed-loop control system electrical (feedback control system) refers to an electrical control system that directly or indirectly feeds back the output to the input end to form a closed loop and participates in control. By introducing a feedback mechanism, the system can adjust the control action according to the change of the output to achieve the predetermined control target.
Features:
* The structure is relatively complex. In addition to the control device and the controlled object, it also includes feedback and comparison links.
* It has the ability to suppress interference and is insensitive to changes in component characteristics.
* It can improve the response characteristics of the system and improve control accuracy and stability.
Application example: The water storage control system of the toilet water tank is a typical application of closed-loop control system electrical. The system detects the water level (output) through a float and feeds back the water level information to the water supply valve (input end) to control the water supply to maintain the water level within a predetermined range. When the water level drops, the valve automatically opens to increase the water supply; when the water level rises, the valve automatically closes to reduce the water supply.
Summary
In the field of control system electrical, open-loop control systems and closed-loop control systems each have their own characteristics and application scenarios. The open-loop control system has a simple structure but low control accuracy; the closed-loop control system has a complex structure but high control accuracy and good stability. In practical applications, the appropriate control system type should be selected according to specific needs and conditions to achieve the best control effect.