A novel online predictive protection method for vibration control systems

Abstract

The present invention discloses a novel online prejudgment protection method for a vibration control system. The host computer presets various specimen quality parameters of the vibration table, calculates and stores the transfer function of the power amplifier system; the vibration control system of the vibration table is subjected to a full-power test before leaving the factory, obtains and stores the maximum voltage and current at different frequency points; the vibration controller obtains the transfer function of the vibration control system through a pre-test, and transmits the data to the power amplifier; according to the transfer function of the vibration control system and various preset specimen quality parameters, the system response and transfer function are calculated and then prejudged and adjusted. During the entire test process, the present invention provides timely, accurate and reliable protection according to the changes in the test conditions, avoiding the damage that may be caused by the failure of the test specimen or power amplifier tested by the client to be effectively protected due to abnormal control of the electric vibration control system, incorrect parameter setting or interference of the table body control.

Description

Technical Field

[0001] The invention relates to the technical field of electric vibration table control methods, and in particular to an online prejudgment protection method for a novel vibration control system. Background Art

[0002] At present, the protection of power amplifiers used in vibration tables is to add voltage or current protection directly to the output of the later stage. Signal interference may occur during the transient process of excitation. Sensor errors, set protection thresholds or response speed problems may cause damage to the power amplifier or damage the test piece on the client's electric vibration table. If there is a problem with the power amplifier, the normal operation of the laboratory's electric vibration table will be affected, resulting in economic loss; damage to the client's important test pieces will be a huge loss for both the laboratory and the test customer. The traditional power amplifier consists of four parts: controller, power amplifier, vibration table body and fan. The controller and power amplifier transmit analog control signals, and the power amplifier directly amplifies the analog signal and drives the vibration table body. The traditional electric vibration system is a system in which the vibration controller is a system and the power amplifier is also a system. Only the vibration controller has independent control and computing capabilities. The vibration controller may bring out random signals due to the switching process, and the analog signal transmission may also be interfered with. The power amplifier may have unreliable protection problems. Various possible abnormalities bring great risks to the vibration system.

[0003] Therefore, a novel online predictive protection method for a vibration control system is provided to solve the problem that during the response process of the vibration control system, uncertain factors may cause abnormalities in the power amplifier or abnormal impact signals may cause damage to the vibration table body or damage to the test pieces on the vibration table body. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a novel online predictive protection method for a vibration control system, comprising the following steps:

[0005] S1. Connect the vibration control system to the vibration table body, preset the test target spectrum, test magnitude, table body, table surface and specimen mass parameters of the vibration control system on the host computer, calculate and store the thrust required for the entire test process of the vibration control system;

[0006] S2. Based on S1, the vibration control system of the vibration table is tested at full power before leaving the factory to obtain and store the transfer function of the power amplifier system and the maximum voltage and current at different frequency points;

[0007] S3, based on S2, the vibration controller obtains the transfer function of the vibration control system through a preliminary test, and transmits the data to the power amplifier, and a two-way data exchange is performed between the power amplifier and the vibration controller;

[0008] S4, based on S3, according to the transfer function of the vibration control system and the preset mass parameters of various specimens, calculate the system response and transfer function, and then determine whether to select to fill in the table and the mass parameters of the specimen;

[0009] S5.1. Based on S4, select and fill in the table surface and specimen mass parameters, calculate and compare the thrust of the vibration table body and the thrust provided by the dynamic coil current under the magnetic field through the specimen values ​​obtained during the test, and verify whether the mass obtained by the host computer is close to the table surface and load mass;

[0010] S5.2, based on S4, choose not to fill in the table and specimen mass parameters, calculate the table and specimen mass through the specimen values ​​obtained during the test process, and estimate the protection thresholds of voltage and current at each frequency point in the full bandwidth to perform online protection on the power amplifier;

[0011] S6.1, based on S5.1, if the mass obtained by the host computer is equal to the calculated mass of the table and the load, it can be determined that the value sampled by the vibration control system is accurate. The protection threshold of the precise dynamic coil voltage and current can be obtained through the mass parameters of the test piece, and the power amplifier can be protected online;

[0012] S6.2, based on S5.1, if the mass obtained by the host computer is not equal to the mass calculated by the table and the load, return to step S5.2 to work.

[0013] Preferably, the specimen mass parameters include: table mass, specimen mass, moving coil mass and system acceleration.

[0014] Preferably, the transfer function of the power amplifier system is:

[0015] Gs1=(a*X^3+b*X^2+c*X+d) / (a1*X^3+b1*X^2+c1*X+d1), where a, b, c, d, a1, b1, c1 and d1 are all system constants of this power amplifier system, and are all real numbers, and X is the system variable in the frequency domain of this power amplifier system.

[0016] Preferably, the transfer function of the vibration control system is:

[0017] Gs2=(a3*X1^3+b3*X1^2+c3*X2+d3) / (a4*X1^3+b4*X1^2+c4*X1+d4), among which a3, b3, c3, d3, a4, b4, c4 and d4 are all system constants of this vibration control system, and are all real numbers. X1 and X2 are system variables in the frequency domain of this vibration controller and vibration table body respectively.

[0018] Preferably, the thrust of the vibration table body is F=BIL=ma, wherein B is the magnetic field provided by the excitation, I is the current provided by the power amplifier, L is the coil length, m is the mass of the moving coil, the table and the specimen, a is the system acceleration, and B and L are constants.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The present invention sets the control target spectrum on the host computer, sets the mass of the test piece, the maximum acceleration and the operating frequency of the electric vibration table, and then according to the setting parameters of the host computer, the vibration controller can calculate the maximum value and the frequency distribution of each frame of data transmission through the transfer function, and transmit the data to the power amplifier. The power amplifier analyzes and calculates the voltage and current amplitude corresponding to the frequency of the output of the next frame according to the data transmitted by the vibration controller through the transfer function, and compares the calculated voltage and current amplitude with the maximum value of the corresponding frequency point actually sampled by the power amplifier. If the current or voltage exceeds the maximum value of the vibration controller, reliable protection can be achieved, and adaptive limiting at different frequency points can be achieved by calculation. The power amplifier solves the problem of abnormal limiting of the input signal according to the limiting conditions provided by the vibration controller. The whole is output through multi-level calculation and data interaction, providing the ability to predict the size and frequency of the amplitude in advance. A follow-up protection system can be set according to the predicted amplitude, thereby realizing accurate prediction of the output voltage and current and reliable protection of the power amplifier and the client test piece. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the work flow chart of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods.

[0023] like Figure 1 As shown, the present invention discloses a novel online prediction protection method for a vibration control system, comprising the following steps:

[0024] S1. Connect the vibration control system to the vibration table body, preset the test target spectrum, test magnitude, table body, table top and specimen mass parameters of the vibration control system on the host computer, calculate and store the thrust required for the entire test process of the vibration control system. The specimen mass parameters include: table top mass, specimen mass, dynamic coil mass and system acceleration, calculate and store the transfer function of the power amplifier system;

[0025] Specifically, the transfer function of the power amplifier system is:

[0026] Gs1=(a*X^3+b*X^2+c*X+d) / (a1*X^3+b1*X^2+c1*X+d1), where a, b, c, d, a1, b1, c1 and d1 are all system constants of this power amplifier system, and are all real numbers, and X is the system variable in the frequency domain of this power amplifier system.

[0027] S2. Based on S1, the vibration control system of the vibration table is tested at full power before leaving the factory to obtain and store the maximum voltage and current at different frequency points. Since the vibration controller and the power amplifier belong to the same vibration control system, the vibration controller and the power amplifier can realize data interactive transmission;

[0028] S3. Based on S2, the vibration controller obtains the transfer function of the vibration control system through a preliminary test and transmits the data to the power amplifier, that is, the vibration controller runs a full-band full-scale based on the frequency range of the table body, and transmits the test instructions to the power amplifier system, wherein the power amplifier records the maximum voltage and maximum current within the corresponding frequency range of the electric vibration table;

[0029] Specifically, the transfer function of the vibration control system is:

[0030] Gs2=(a3*X1^3+b3*X1^2+c3*X2+d3) / (a4*X1^3+b4*X1^2+c4*X1+d4), among which a3, b3, c3, d3, a4, b4, c4 and d4 are all system constants of this vibration control system, and are all real numbers. X1 and X2 are system variables in the frequency domain of the vibration controller and the vibration table body respectively. The relationship between the acceleration and the output of the vibration controller can be accurately calculated through the transfer function of the vibration control system. The parameters of the output voltage can be predicted during the operation of the vibration control system according to the magnitude of the target spectrum. The power amplifier system can accurately calculate the frequency band and magnitude relationship through the parameters provided by the vibration control system, and obtain the estimated output current, thereby realizing adaptive protection in the control process.

[0031] S4, based on S3, according to the transfer function of the vibration control system and the preset mass parameters of various specimens, calculate the system response and transfer function, and then determine whether to select to fill in the table and the mass parameters of the specimen;

[0032] S5.1. Based on S4, select and fill in the table and specimen mass parameters, calculate and compare the thrust of the vibration table body and the thrust provided by the dynamic coil current under the magnetic field through the specimen values ​​obtained during the test, and the power amplifier analyzes and calculates the voltage and current amplitude corresponding to the frequency of the next frame output according to the data transmitted by the vibration controller through the transfer function Gs1, and verifies whether the mass obtained by the host computer is close to the mass of the table and the load;

[0033] Specifically, the thrust F of the vibration table body is F=BIL=ma, where B is the magnetic field provided by the excitation, I is the current provided by the power amplifier, L is the coil length, m is the mass of the moving coil, table and specimen, a is the system acceleration, B and L are constants, and during the test, B and L do not change. The thrust F is positively correlated with the current I. During the full-scale test, m and a are both known quantities. According to the changing trend of the current I, the thrust performance of the entire vibration control system can be calculated, and the value of B*L can be fitted; during the pre-test, the acceleration parameter a and the moving coil current I are obtained, and the mass of the table plus the load can be calculated.

[0034] S5.2, based on S4, choose not to fill in the table and specimen mass parameters, calculate the table and specimen mass through the specimen values ​​obtained during the test process, and estimate the protection thresholds of voltage and current at each frequency point in the full bandwidth to perform online protection on the power amplifier;

[0035] S6.1, based on S5.1, if the mass obtained by the host computer is equal to the calculated mass of the table and the load, it can be determined that the value sampled by the vibration control system is accurate. The protection threshold of the precise dynamic coil voltage and current can be obtained through the mass parameters of the test piece, and the power amplifier can be protected online;

[0036] S6.2, based on S5.1, if the mass obtained by the host computer is not equal to the mass calculated by the table and the load, return to step S5.2 to work.

[0037] The present invention sets the control target spectrum on the host computer, sets the mass of the test piece, the maximum acceleration and the working frequency of the electric vibration table body, and then according to the setting parameters of the host computer, the vibration controller can calculate the maximum value and the distributed frequency of each frame of data transmission through the transfer function, and transmit the data to the power amplifier. The power amplifier analyzes and calculates the voltage and current amplitude corresponding to the frequency of the output of the next frame through the transfer function according to the data transmitted by the vibration controller, and compares the calculated voltage and current amplitude with the maximum value of the corresponding frequency point actually sampled by the power amplifier. Reliable protection can be achieved when the maximum current or voltage exceeds the maximum current or voltage of the vibration controller, and adaptive limiting at different frequency points can be achieved through calculation. The power amplifier solves the problem of abnormal limiting of the input signal according to the limiting conditions provided by the vibration controller. The whole is output through multi-level calculation and data interaction, providing the size and frequency of the amplitude that can be predicted in advance. A follow-up protection system can be set according to the predicted amplitude, thereby realizing accurate prediction of the output voltage and current and reliable protection of the power amplifier.

[0038] During the entire test process, the present invention provides timely, accurate and reliable protection according to the changes in the test conditions, and avoids possible damage to the test piece or power amplifier tested by the client due to abnormal control, parameter setting errors or interference caused by abnormal control of the electric vibration control system, resulting in the test piece or power amplifier being tested by the client not being effectively protected. In the vibration control system of the present invention, whether the vibration controller calculates the protection parameters according to the test conditions and transmits them to the power amplifier; or the vibration controller calculates the drive, transmits the target value to the power amplifier, and the power amplifier calculates the protection parameters, all belong to the technical solution of the present invention.

[0039] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of rights of the present invention. Therefore, modifications, equivalent changes, improvements, etc. made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A novel online predictive protection method for a vibration control system, characterized in that: The following steps are involved: S1. Connect the vibration control system to the vibration table body, preset the test target spectrum, test magnitude, table body, table surface and specimen mass parameters of the vibration control system on the host computer, calculate and store the thrust required for the entire test process of the vibration control system; S2. Based on S1, the vibration control system of the vibration table is tested at full power before leaving the factory to obtain and store the transfer function of the power amplifier system and the maximum voltage and current at different frequency points; S3, based on S2, the vibration controller obtains the transfer function of the vibration control system through a preliminary test, and transmits the data to the power amplifier, and a two-way data exchange is performed between the power amplifier and the vibration controller; S4, based on S3, according to the transfer function of the vibration control system and the preset mass parameters of various specimens, calculate the system response and transfer function, and then determine whether to select to fill in the table and the mass parameters of the specimen; S5.

1. Based on S4, select and fill in the table surface and specimen mass parameters, calculate and compare the thrust of the vibration table body and the thrust provided by the dynamic coil current under the magnetic field through the specimen values ​​obtained during the test, and verify whether the mass obtained by the host computer is close to the table surface and load mass; S5.2, based on S4, choose not to fill in the table and specimen mass parameters, calculate the table and specimen mass through the specimen values ​​obtained during the test process, and estimate the protection thresholds of voltage and current at each frequency point in the full bandwidth to perform online protection on the power amplifier; S6.1, based on S5.1, if the mass obtained by the host computer is equal to the calculated mass of the table and the load, it can be determined that the value sampled by the vibration control system is accurate. The protection threshold of the precise dynamic coil voltage and current can be obtained through the mass parameters of the test piece, and the power amplifier can be protected online; S6.2, based on S5.1, if the mass obtained by the host computer is not equal to the mass calculated by the table and the load, return to step S5.2 to work.

2. The online predictive protection method of a novel vibration control system according to claim 1 is characterized in that: The specimen mass parameters include: table mass, specimen mass, moving coil mass and system acceleration.

3. The online predictive protection method of a novel vibration control system according to claim 2 is characterized in that: The transfer function of the power amplifier system is: Gs1=(a*X^3+b*X^2+c*X+d) / (a1*X^3+b1*X^2+c1*X+d1), where a, b, c, d, a1, b1, c1 and d1 are all system constants of this power amplifier system, and are all real numbers, and X is the system variable in the frequency domain of this power amplifier system.

4. The online predictive protection method of a novel vibration control system according to claim 2 is characterized in that: The transfer function of the vibration control system is: Gs2=(a3*X1^3+b3*X1^2+c3*X2+d3) / (a4*X1^3+b4*X1^2+c4*X1+d4), among which a3, b3, c3, d3, a4, b4, c4 and d4 are all system constants of this vibration control system, and are all real numbers. X1 and X2 are system variables in the frequency domain of this vibration controller and vibration table body respectively.

5. The online predictive protection method of a novel vibration control system according to claim 1 is characterized in that: The thrust of the vibration table body is F=BIL=ma, wherein B is the magnetic field provided by the excitation, I is the current provided by the power amplifier, L is the coil length, m is the mass of the moving coil, the table and the specimen, a is the system acceleration, and B and L are both constants.

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