Among the huge variety of multifunctional devices that are designed for professional switching and control, the proportional regulator has received a huge demand. This unit is successfully used by specialists to provide feedback. The device can be installed in systems with automated control in order to maintain the value of a certain parameter at a given level. Most often, such a regulator is operated by specialists in the field of temperature control and other important quantities that are involved in various processes.
Description
The classic proportional controller is best suited for interaction with control loops, the scheme of which is equipped with feedback links. Experts use equipment in automated signal conditioning systemsmanagement. As a result, high quality and precision of transferred processes can be achieved. The proportional controller consists of three basic components that interact with each other as much as possible. Experts note that each of them is in proportion to a certain value. If at least one component falls out of this process for any reason, then the installation will not be able to fully perform its duties.
Design
Proportional controllers being implemented today are in great demand in facilities that allow statistical error. For such units, the main movement of the regulating body is fully proportional to the deviation of the controlled value. Unlike similar devices, proportional products have a fairly stable operation on objects with significant inertia.
The design feature of the units is that the manufacturers have provided for the presence of a rigid feedback, which guarantees the constancy of the adjustment process of various objects. Specialists need to be prepared for the occurrence of a statistical error in the control function. If we take into account the fact that the dead zone of the amplifier and the exact travel time of the executive body during the adjustment process remain unchanged, then the main dynamic tuning parameter is the proportional band. Most often, professionals perform all the necessary manipulations during the installation of the steam pressure regulator in the boiler drum.
Working principle
Proportional-integral controller, like all self-balancing units, boasts the presence of three main mechanisms: input, error detection, output. All parts differ in their characteristics, as well as operational features. In the body of the equipment, all active mechanisms are located in such a way that the controlling element produces an output proportional to its input. The primary mechanism converts any change in the variable process into a certain mechanical movement or physical change. It is worth noting that changes affecting the unit bring it out of balance. Mechanical and physical movement is perceived by the equipment. The output from the error detection mechanism, called back pressure, changes according to the actual input parameters. Absolutely all proportional pressure regulators, regardless of the mechanism used, are equipped with two basic settings. Due to this, the end user can know the actual value around which the unit will provide corrective actions.
Functionality
Multifunctional proportional-differential controller specialists turn on automatically at a load that corresponds to the steepest characteristic of the responsible body. The system registers the transient process when the plant is disturbed within 5%. If the equipment is stable, thenWith the help of a successive decrease in the set proportional band, it is possible to achieve the appearance in the system of an undamped self-oscillatory process. During scheduled tests, the period of critical self-oscillations and the residual non-uniformity of regulation are necessarily fixed, at which the installation enters the mode of undamped oscillations.
Practice of use
Demanded today proportional-integral-derivative controller allows you to continuously maintain a given value of any value for a certain time period. For these purposes, a change in voltage and other parameters is used, which each specialist can calculate using a formula. The plant size and setpoint must be taken into account, as well as any difference or mismatch.
In practice, system regulation is rarely analyzed. This is due to the lack of valuable information about the characteristics of the controlled object, when it is simply not possible to use the differentiating component. The operating range is simply limited by the upper and lower limits. Due to the existing non-linearity, each subsequent setting is experimental. It is performed when the object is connected to the control system.
Responsible mechanisms
In the work environment, technicians often use the current P Gain of the controller to ensure that the plant operates as smoothly as possible. The formation of the output signal is carried out by this parameter. The signal perfectly keeps the input value to be adjusted at the optimum level and does not allow it to deviate. In accordance with the increase in the coefficient, the signal level also increases. If at the input of the unit the controlled value simply equals the value set by specialists, then the final output will be 0. In practice, it is quite difficult to adjust the desired parameter with just one proportional component in order to stabilize it at a certain level.
Conclusion
Due to the use of differential control, the system gets an excellent opportunity to fully compensate for a possible future error. The correct calculation of the proportional component numerically looks like the difference between the previous and current parameter, multiplied by the control factor. Since specialists actively use measurements made in a short period of time, any errors and external factors greatly affect the process. Because of all these nuances, pure differential control is difficult to implement for most modern systems.
