What do you mean by open-loop and closed-loop cars?

Open-loop and closed-loop in automobile refer to the control form of circuit feedback in automobile electronic system, and open-loop control refers to input control and output control; Closed-loop control is to add a feedback on the basis of open-loop control, so that the output acts on the input in turn.

Open-loop control system requires high accuracy of engine and control system, but the control accuracy is low. When the working condition of the oxygen-free sensor exceeds the predetermined range, it will not be controlled.

In the closed-loop control system, an oxygen sensor is installed on the exhaust pipe of the engine to judge the air-fuel ratio of the mixture actually entering the cylinder according to the change of oxygen content in the exhaust, and then compare it with the set target air-fuel ratio through the computer, and correct the fuel injection amount according to the error. The air-fuel ratio control accuracy is high.

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Working principle of automobile open-loop control system

The open-loop control system of automobile is to control the generation and distribution of pulses through the operation controller (which can be a microcomputer or a single chip microcomputer) and the preset processing program instructions, and send out corresponding pulses; Then these pulses drive the stepping motor, and the precision transmission mechanism drives the workbench to process. If the pulse can not be lost and the influence of interference can be effectively suppressed, then the precision transmission mechanism is adopted.

The advantages of open-loop system are no feedback link, simple structure, good system stability and low cost. Therefore, when the relationship between output and input is fixed, the disturbance factors such as internal parameters or external load are not big, or the errors caused by these disturbance factors can be determined and compensated in advance, the open-loop control system can be adopted.