CN-121763080-B - Rapid and accurate prediction method for duty ratio-frequency response characteristic of high-speed switch valve

CN121763080BCN 121763080 BCN121763080 BCN 121763080BCN-121763080-B

Abstract

The invention discloses a rapid and accurate prediction method of the duty ratio-frequency response characteristic of a high-speed switching valve, and belongs to the field of high-speed switching valves. The method comprises the steps of firstly, periodically opening and closing a to-be-detected high-speed switch valve according to a selected driving mode, recording the motion state of a valve core of the high-speed switch valve and the starting and ending time of each motion state to obtain the opening lag time, the opening motion time, the closing lag time and the closing motion time of the high-speed switch valve, then calculating a duty ratio dividing value, respectively establishing a relation between the highest working frequency of the high-speed switch valve and the duty ratio when the duty ratio dividing value is larger than the duty ratio dividing value and a relation between the highest working frequency of the high-speed switch valve and the duty ratio when the duty ratio dividing value is smaller than the duty ratio dividing value, and combining the two relation to generate a duty ratio-frequency response characteristic curve. The invention can realize the rapid generation of the duty ratio-frequency response curve through the measurement of the dynamic characteristic and the current characteristic at one time.

Inventors

ZHONG QI
CHEN WANHENG
YAN XUEJIAN
LI XIAOTIAN
XU ENGUANG

Assignees

浙江工业大学

Dates

Publication Date: 20260512
Application Date: 20260303

Claims (10)

1. A rapid and accurate prediction method for the duty ratio-frequency response characteristic of a high-speed switch valve is characterized by comprising the following steps: 1) Under the selected driving mode, the high-speed switch valve to be detected is subjected to opening and closing test, so that the opening lag time, the opening movement time, the closing lag time and the closing movement time of the high-speed switch valve are obtained; 2) Obtaining a duty ratio boundary value of the high-speed switching valve to be tested in a selected driving mode according to each time obtained in the step 1); 3) Establishing a relation between the highest working frequency of the high-speed switching valve and the duty ratio according to the opening lag time and the opening movement time in a section with the duty ratio smaller than the duty ratio demarcation value; 4) And combining the relation between the highest working frequency of the high-speed switch valve under different duty ratios and the duty ratio to obtain a duty ratio-frequency response characteristic curve of the high-speed switch valve under a given driving mode, wherein the duty ratio-frequency response characteristic curve is a relation between the duty ratio and the highest working frequency under the duty ratio.
2. The method of claim 1, wherein the driving mode in step 1) is single voltage driving, three voltage driving or preloaded multi-voltage driving; The single-voltage driving divides one opening and closing period of the high-speed switch valve into an opening stage and a closing stage, wherein fixed high voltage is applied in the opening stage, and zero voltage is applied in the closing stage; the three-voltage driving divides one opening and closing period of the high-speed switch valve into an opening stage, an opening maintaining stage, a closing stage and a closing maintaining stage, wherein fixed high voltage is applied in the opening stage, maintaining voltage is applied in the opening maintaining stage, reverse high voltage is applied in the closing stage, and zero voltage is applied in the closing maintaining stage; The pre-loaded multi-voltage drive is provided with a pre-loaded voltage stage before the starting stage of the three-voltage drive, and the pre-loaded voltage stage applies pre-loaded voltage to the high-speed switch valve so as to maintain the coil current at a stable value smaller than the starting current.
3. The method of claim 2, wherein the sustain voltage applied to the high-speed switching valve is a high voltage having a set duty ratio during a three-voltage-driven on-sustain period, and the coil current in the high-speed switching valve is maintained at the off current by the sustain voltage Stable values of 5% -10% above And in the opening maintaining stage, the valve core of the high-speed switch valve is kept fully opened.
4. The method according to claim 1, wherein in step 1), the opening and closing test of the to-be-detected high-speed switching valve is performed, including: and driving the valve to be detected at high speed according to the selected driving mode, and recording the movement state of the valve core of the valve at high speed, and the starting time and the ending time of each movement state to obtain the starting time, the full opening time, the starting closing time and the full closing time of the valve core.
5. The method of claim 4, wherein in step 1), the opening lag time is a difference between a valve element start opening time and an opening stage initial time, the opening movement time is a difference between a full opening time and a valve element start opening time, the closing lag time is a difference between a valve element start closing time and a closing stage initial time, the closing movement time is a difference between a full closing time and a valve element start closing time, the opening stage initial time is a driving signal rising edge time of a driving mode, and the closing stage initial time is a driving signal falling edge time.
6. The method according to claim 2, wherein the valve element starting opening time is the time when the valve element is converted from a static state to an opening motion, the full opening time is the time when the valve element is fully opened, the starting closing time is the time when the valve element is converted from the full opening to the closing motion, the full closing time is the time when the valve element is fully closed, the valve element starting opening time, the full opening time, the starting closing time and the full closing time are obtained by detecting the valve element motion state and the time corresponding to each motion state by a valve element displacement sensor, or by detecting the current curve of the high-speed switch valve, and the current curve characteristic is obtained.
7. The method of claim 1, wherein step 2) the duty cycle demarcation value is related to a drive mode, wherein: In the single voltage driving mode, the duty ratio demarcation value is: ; in the three-voltage driving mode, the duty ratio demarcation value is: ; in the multi-voltage driving mode, the duty ratio demarcation value is: ; Wherein, the 、 The opening lag time and the closing lag time respectively, 、 The opening movement time and the closing movement time, respectively.
8. The method according to claim 1, wherein in step 3), in the interval in which the duty cycle is smaller than the duty cycle boundary value, The highest working frequency in the single-voltage driving mode is in direct proportion to the duty ratio, and the proportionality coefficient is the reciprocal of the sum of the opening lag time and the opening movement time; the highest operating frequency in the three-voltage drive mode and the multi-voltage drive mode is proportional to the duty cycle, and the proportionality coefficient is the inverse of the value obtained by subtracting the off lag time from the sum of the on lag time and the on movement time.
9. The method according to claim 1, wherein in the step 3), the duty ratio is recorded as Highest operating frequency and frequency in single voltage driving mode and three voltage driving mode Proportional, the proportionality coefficient is the inverse of the sum of the closing lag time and the closing movement time; maximum operating frequency in multi-voltage driving mode Proportional to the reciprocal of the value obtained by subtracting the opening lag time from the sum of the closing lag time and the closing movement time.
10. A fast and accurate prediction system for the duty cycle-frequency response characteristics of a high-speed switching valve implementing the method of claim 1, comprising: The opening and closing test system is used for periodically opening and closing the to-be-detected high-speed switch valve according to the selected driving mode, recording the motion state of the valve core of the high-speed switch valve and the starting and ending time of each motion state, and obtaining the opening lag time, the opening motion time, the closing lag time and the closing motion time of the high-speed switch valve; The duty ratio dividing value calculating unit is used for calculating a duty ratio dividing value according to the opening lag time, the opening movement time, the closing lag time and the closing movement time which are obtained by the opening and closing test system; The duty ratio-frequency response characteristic curve generation module is used for respectively establishing a relation between the highest working frequency of the high-speed switch valve and the duty ratio when the duty ratio demarcation value is larger than the duty ratio demarcation value and a relation between the highest working frequency of the high-speed switch valve and the duty ratio when the duty ratio demarcation value is smaller than the duty ratio demarcation value according to the opening lag time, the opening movement time, the closing lag time and the closing movement time which are obtained by the opening and closing test system, and combining the two relation to generate the duty ratio-frequency response characteristic curve.

Description

Rapid and accurate prediction method for duty ratio-frequency response characteristic of high-speed switch valve Technical Field The invention belongs to the field of high-speed switch valves, and particularly relates to a rapid and accurate prediction method of a duty ratio-frequency response characteristic of a high-speed switch valve. Background The high-speed switch valve is used as a core element of a digital hydraulic technology, realizes high-precision control of flow and pressure through high-frequency opening and closing actions, has the advantages of high response speed, high reliability, strong pollution resistance and the like, and is widely applied to the fields of aerospace, engineering machinery, high-end manufacturing and the like. In a hydraulic system, the frequency response characteristic of a high-speed switch valve is an important index for measuring the dynamic performance of the high-speed switch valve, determines the highest working frequency of the high-speed switch valve which can be stably opened and closed under different driving conditions, and directly influences the control bandwidth, dynamic response and stability of the system. When the driving frequency exceeds the limit frequency of the valve, the valve core cannot be completely opened and closed, and flow fluctuation, pressure oscillation and even system instability are easily caused. Therefore, obtaining the full duty cycle-frequency response curve of a high speed switching valve is of great significance to valve design optimization and system application. In the prior art, the acquisition of the duty cycle-frequency response curve mainly depends on a point-by-point frequency scanning method. The basic principle of the method is that the duty ratio of a driving signal is fixed firstly, then the frequency of an input signal is gradually increased, and a period of stable time is required to be kept for each frequency point to be increased so as to ensure that the high-speed switching valve fully responds under the condition. And then, judging whether the valve core can be completely opened or closed by measuring signals such as flow change, valve core displacement curve or outlet pressure fluctuation and the like of the valve. If the valve core can still stably complete the full-opening and full-closing actions under the frequency, the frequency is considered to be acceptable, and when the frequency is continuously increased to the point that the valve core cannot be fully opened and closed, the frequency is judged to be the highest working frequency under the duty ratio. By repeating the above process at different duty cycles, a duty cycle-frequency response curve is drawn point by point. However, this approach, while intuitive, has significant limitations. First, the efficiency of the test is low, each duty cycle requires multiple frequency boosting and long-time observation, and the test process often takes hours. Secondly, the method relies on a special hydraulic test bed and a high-precision sensor, and has harsh experimental conditions and high cost. Again, the test results are susceptible to factors such as oil temperature, contamination, installation errors, and operational experience, resulting in insufficient repeatability and consistency. Therefore, existing point-by-point scanning methods are difficult to meet practical needs, especially in design stages and field applications. There is an urgent need for a method that can rapidly and quantitatively predict a complete duty cycle-frequency response curve under limited experimental conditions to improve test efficiency, reduce cost, and enhance reliability and versatility of results. Disclosure of Invention The invention aims to overcome the defects of the prior art and provides a rapid and accurate prediction method for the duty ratio-frequency response characteristic of a high-speed switching valve. According to the method, the relation between the duty ratio-frequency response characteristic of the high-speed switching valve and the on-off time of the high-speed switching valve is analyzed through theory, then the on-off time parameters of the valve core are obtained through direct detection of a laser displacement sensor or indirect detection of the coil current characteristic through experiments, and the key time parameters are used as input to be substituted into a prediction formula, so that a complete duty ratio-frequency response curve can be calculated rapidly. In order to achieve the above object, the present invention provides a fast and accurate prediction method for duty ratio-frequency response characteristics of a high-speed switching valve, comprising the steps of: 1) Under the selected driving mode, the high-speed switch valve to be detected is subjected to opening and closing test, so that the opening lag time, the opening movement time, the closing lag time and the closing movement time of the high-speed switch valve are obtained; 2) Obtaining