1. The closed-loop control
is a basic concept of control loop control theory. Return means in a manner as controlled as to output a control input terminal, and a method of controlling the relationship between the control input of impact is applied. In control theory, generally refers to the output terminal by a closed loop ldquo; Sidechain rdquo; way back to the input, a so-called closed-loop control. Back to the output terminal of the input terminal and an output terminal involved in control and then, this is the purpose of closed-loop control, this object is achieved by feedback.
What is a closed loop control
closed loop control is to control the correction according to the controlled object output feedback, it is measured the actual and planned deviation occurs by standards for fixed or corrected. Closed-loop control, the change amount extracted from the output control signal as a feedback quantity to the comparison input of the control input, and an amount generally taken this input opposite in phase, so called negative feedback control, automatic control is normally closed-loop control. Such as control of household air temperature
In the control theory, by the output of the closed loop usually refers ldquo; Sidechain rdquo; way back to the input, a so-called closed-loop control. Back to the output terminal of the input terminal and an output terminal involved in control and then, this is the purpose of closed-loop control, this object is achieved by feedback. Positive and negative feedback loop control is common in two basic forms. Wherein the negative feedback and the positive feedback has the same meaning from speaking to the angle of purposes. After feedback manner, i.e. back to the input terminal, a unity input and integrating subtraction output; DETAILED feedback from the implementation point of view, belongs to positive and negative feedback on the algebraic or arithmetic ldquo meaning; subtraction rdquo as the new control output, to further control output. In fact, the output of the feedback input much more than this way. This is as follows: the operation, more than just addition and subtraction, but also including more wide area of mathematics; on the way back, output feedback on the amount of input, not necessarily take a unified control integrated operation with input formOutput, output controls may be applied directly to the control input of the chain and the like.
Application of a closed loop
For example, the above cited car engine combustion control:
EFI closed-loop control of the engine system is a real oxygen sensor, triangular relationship between the closure means and the three fuel amount control computer. Oxygen sensor ldquo; tell rdquo; air-fuel mixture gas where the computer, the computer issues a command to the fuel quantity control means to adjust the air-fuel ratio toward the theoretical value (14.7: 1). This adjustment is often little more than the theoretical value, the oxygen sensor to detect it and report the computer, the computer then issues a command transfer back to 14.7: 1. Because each adjustment cycle very quickly, so the air-fuel ratio will not deviate from 14.7: 1, once running, the closed-loop continuous adjustments. EFI engine uses a closed-loop control, since the engine can always run in ideal conditions (air-fuel ratio is not too much deviation from the theoretical value), which can not only ensure the car has better dynamic performance, but also fuel-efficient.
EFI closed-loop control of the engine system is a real oxygen sensor, the computer and the closure triangular relationship between the fuel quantity control means three. Oxygen sensor ldquo; tell rdquo; air-fuel mixture gas where the computer, the computer issues a command to the fuel quantity control means to adjust the air-fuel ratio toward the theoretical value (14.7: 1). This adjustment is often little more than the theoretical value, the oxygen sensor to detect it and report the computer, the computer then issues a command transfer back to 14.7: 1. Because each adjustment cycle very quickly, so the air-fuel ratio will not deviate from 14.7: 1, once running, the closed-loop continuous adjustments. EFI engine uses a closed-loop control, since the engine can always run in ideal conditions (air-fuel ratio is not too much deviation from the theoretical value), which can not only ensure the car has better dynamic performance, but also fuel-efficient.