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CN-121978903-A - Sampling parameter self-adaptive adjustment method and application thereof in automobile sensor

CN121978903ACN 121978903 ACN121978903 ACN 121978903ACN-121978903-A

Abstract

The application is suitable for the technical field of self-adaptive control, in particular to a sampling parameter self-adaptive adjustment method and application thereof in an automobile sensor, wherein the method comprises the steps that a controller continuously samples, quantifies and encodes a first signal detected by a controlled object to obtain a second signal, and the length of the second signal is n times of the sampling period; when the controller obtains a second signal, the output quantity of the actuator is regulated and controlled according to the second signal, the current second signal and the previous m-1 second signals are spliced into a third signal, the first power of the third signal in the first frequency domain range and the second power of the third signal in the second frequency domain range are determined on the power spectrum density, a stability vector is determined according to the first power and the second power of each third signal, and n and m are adjusted according to the continuous m stability vectors. The sampling parameters can be adaptively adjusted according to the stability of the signals, and the regulation and control frequency is improved on the premise of ensuring the control precision.

Inventors

  • ZHANG WENJIE
  • WU YUEHUA

Assignees

  • 温州华珏汽车电子科技有限公司

Dates

Publication Date
20260505
Application Date
20260409

Claims (10)

  1. 1. A method for adaptively adjusting a sampling parameter, the method being applied to a controller in a closed-loop control system, the method comprising: the controller continuously samples, quantizes and encodes a first signal detected by a controlled object to obtain a second signal, wherein the length of the second signal is n times of a sampling period, n is a positive integer, and the sampling period is a sampling period when the first signal is sampled; When the controller obtains one second signal, regulating and controlling the output quantity of an actuator according to the second signal, simultaneously splicing the current second signal and m-1 previous second signals into a third signal, and determining the first power of the third signal in a first frequency domain range and the second power of the third signal in a second frequency domain range on the power spectrum density, wherein the first frequency domain range is the range of normal regulating and controlling frequency when the controller regulates and controls, and the second frequency domain range is the range from a frequency domain zero point to the first frequency domain range; Determining a stability vector based on said first power and said second power of each of said third signals, wherein differences between a plurality of consecutive said stability vectors are used to reflect the degree of stability of said first signal; and adjusting the n and the m according to the m continuous stable vectors.
  2. 2. The method of adaptive adjustment of sampling parameters according to claim 1, wherein after obtaining the third signal, the method further comprises: and downsampling the third signal, and replacing the original third signal with the downsampled third signal.
  3. 3. The sampling parameter adaptive adjustment method according to claim 1, wherein said adjusting said n and said m according to consecutive said m stabilization vectors comprises: When the sizes of the m continuous stable vectors reach the standard and the phase offset among the m continuous stable vectors does not exceed a threshold value, decreasing n and increasing m to enable the product of n and m to be a constant value, wherein when the sizes of the stable vectors/the total power of the third signal > I1, the sizes of the stable vectors are considered to reach the standard, and I1 is more than 0 and less than 1; and when the size of any one of the m continuous stable vectors does not reach the standard, or the phase offset between the m continuous stable vectors exceeds a threshold value, the n and the m are recalled to be initial values.
  4. 4. A method for adaptively adjusting a sampling parameter as in claim 3, wherein after said n is reduced, said method further comprises: Setting an neglected area with a duration of a first duration, wherein n and m are not recalled to be initial values in the neglected area, and the first duration=m×n×sampling period.
  5. 5. The method of adaptive adjustment of sampling parameters according to claim 1, wherein said n and said m are both powers of 2.
  6. 6. The adaptive adjustment method of sampling parameters according to claim 2, wherein n and m are each a power of 2, and the interval of downsampling is also a power of 2 when downsampling the third signal.
  7. 7. The sampling parameter adaptive adjustment method according to claim 1, wherein the purpose of adjusting the n and the m is to shorten the sampling time of the second signal; The controller is capable of performing multi-threaded parallel operations.
  8. 8. The sampling parameter adaptive adjustment method according to any one of claims 1 to 7, characterized in that the closed-loop control system is an injection amount regulation system of an automobile, the controller is an ECU of the automobile, the controlled object is an oxygen sensor, the actuator is an injector, and the output amount is an injection amount.
  9. 9. Use of a sampling parameter adaptive adjustment method according to any one of claims 1 to 8 in an automotive sensor detection signal sampling parameter adaptive adjustment, wherein an ECU of the automotive runs the sampling parameter adaptive adjustment method according to any one of claims 1 to 8 to adaptively adjust automotive sensor detection signal sampling parameters n and m.
  10. 10. An electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the method of any one of claims 1 to 8 when the computer program is executed.

Description

Sampling parameter self-adaptive adjustment method and application thereof in automobile sensor Technical Field The application belongs to the technical field of self-adaptive control, and particularly relates to a sampling parameter self-adaptive adjustment method and application thereof in an automobile sensor. More particularly, the application relates to a sampling parameter adaptive adjustment method based on power spectral density analysis, which is used for optimizing signal sampling parameters in a closed-loop control system, and an electronic device applying the method. Background In various closed-loop control systems, a controller generally needs to periodically sample a continuous signal output by a controlled object (such as a sensor), convert an analog signal into a digital signal, and further calculate a control amount according to the digital signal and drive an actuator. The selection of sampling parameters (such as sampling points and sampling periods) directly affects the response speed and control accuracy of the system, namely, excessive sampling points can improve the signal accuracy, but the sampling time and the signal processing time can be prolonged, so that the regulation frequency is reduced, and key information can be lost and the control stability is affected if the sampling points are too small. In the prior art, most systems adopt fixed sampling parameters (fixed sampling points) to sample signals, so that not only can fixed and longer sampling time be spent, but also the processing time of a control system to digital signals with fixed sequence length is approximately the same, and the sampling time and the signal processing time can directly influence the regulation and control speed of a closed-loop control system, so that the requirements of signal dynamic change cannot be met. When the controlled signal tends to be stable, the continuous maintenance of the larger sampling point number can cause unnecessary waste of calculation resources, and the improvement of the response speed of the system is limited, and when the signal fluctuation is severe, the fixed smaller sampling point number can not capture enough signal details. Therefore, a method for adaptively adjusting the sampling parameters according to the signal stability is needed to increase the control frequency as much as possible while ensuring the control accuracy. As a typical application scenario, in an exhaust system of a modern automobile, the exhaust system comprises an oxygen sensor and a three-way catalyst, when an engine exhausts through the oxygen sensor, the oxygen sensor can detect oxygen content in exhaust gas and generate an electric signal, an electronic control system ECU of the automobile obtains an air-fuel ratio (the air-fuel ratio is a mass ratio of air to fuel in the mixture) according to the electric signal, when the air-fuel ratio is 14.7:1, the produced exhaust gas can be catalyzed into harmless gas to the greatest extent by the three-way catalyst, the ECU controls the fuel injection amount of a fuel injector to enable the air-fuel ratio to oscillate up and down around 14.7:1 so as to maintain dynamic balance, and the ECU and the oxygen sensor realize closed loop control. The signal of the oxygen sensor is continuous and analog, the ECU obtains discrete and digital signals after sampling the analog signals for a plurality of times, and the digital signals are filtered, averaged and the like to obtain more accurate oxygen content, and then the air-fuel ratio is determined according to the oxygen content, and the closed-loop control of the fuel injection quantity is carried out. In the existing automobile ECU and oxygen sensor architecture, in order to obtain oxygen content information with sufficient accuracy, the ECU often obtains digital signals with the same sequence length in a sufficient and fixed sampling mode, which not only can take a fixed and longer sampling time, but also can substantially have the same processing time of the digital signals with the same sequence length, and both the sampling time and the signal processing time of the ECU can directly influence the regulation and control speed of the ECU, so that the regulation and control frequency of the fuel injection quantity regulation and control system of the automobile is slowed down (the direct consequences of the slowing down of the regulation and control frequency include the reduction of air-fuel ratio control accuracy, the increase of harmful emissions, the deterioration of driving smoothness and idle speed stability, and the like). Disclosure of Invention The embodiment of the application provides a sampling parameter self-adaptive adjustment method and application thereof in an automobile sensor, which can solve the problem that the regulation frequency is slow due to the adoption of fixed sampling parameters in the existing closed-loop control system, and particularly can solve the problem that the regulation fre