CN102880198A - Structural vibration semi-active control system based on asymmetrical control circuit - Google Patents

Abstract

The invention discloses a structure vibration semi-active control system based on an asymmetrical control circuit. The structural vibration semi-active control system based on an asymmetric control circuit includes a piezoelectric drive unit, an asymmetric control circuit, a piezoelectric sensing unit, and a system circuit. The asymmetric control circuit is composed of diodes connected in series, capacitors, and diodes connected in parallel composed of switches at both ends. By changing the composition of the switch unit in the system circuit, the present invention realizes the asymmetric reversal of the voltage at both ends of the piezoelectric element in SSDI and SSDV technologies, expands the selectable range of the piezoelectric element in semi-active vibration control, and more effectively controls the structural vibration. It has a broad application prospect in structural vibration control.

Description

Semi-active Control System of Structural Vibration Based on Asymmetric Control Circuit

technical field

The invention relates to a structural vibration control system, in particular to a structural vibration semi-active control system based on an asymmetrical control circuit.

Background technique

The high-frequency response characteristics and electromechanical coupling characteristics of piezoelectric materials make them widely used in the intelligentization of structures and vibration control. At present, the structural vibration control methods based on piezoelectric materials can be mainly divided into three types: active control, passive control and semi-active control. Piezoelectric semi-active control method is a new vibration control method developed based on piezoelectric active and passive control technology, and is currently being widely studied. A representative one is a semi-active vibration control method based on nonlinear synchronous switch damping technology. This method is called SSD technology (SSD: Synchronized Switch Damping), and some simple electronic components such as inductors and switches are connected in series in the circuit. The electric energy on the piezoelectric element is quickly consumed or the voltage is reversed, so as to achieve the purpose of vibration reduction. Compared with passive and active control methods, the control system of this method is simple, and only the external energy is required for the switching operation, so the external energy required for control is very small, does not require an accurate structural vibration model, and the control effect is relatively stable, suitable for broadband With vibration control, these make this method have broad research prospects in structural vibration control. At present, semi-active vibration control methods based on nonlinear synchronous switching damping technology are mainly divided into four types, short-circuit synchronous switching damping technology (SSDS technology), inductive synchronous switching damping technology (SSDI technology), voltage synchronous switching damping technology (SSDV technology) And negative capacitance synchronous switch damping technology (SSDNC technology).

In previous studies, for the semi-active vibration control method of nonlinear synchronous switch damping technology, the voltage reversal at both ends of the piezoelectric element is symmetrical, while for piezoelectric elements that require voltage asymmetrical reversal, such as piezoelectric fiber composites MFC (MFC: Macro Fiber Composite), etc., this method has its limitations.

Contents of the invention

The technical problem to be solved by the present invention is to provide a semi-active control system for structural vibration based on an asymmetrical control circuit in view of the deficiency of the above-mentioned background technology.

The present invention adopts the following technical solutions in order to realize the above-mentioned purpose of the invention:

A structural vibration semi-active control system based on an asymmetric control circuit, including: a piezoelectric drive unit, an asymmetric control circuit, a piezoelectric sensing unit, and a system circuit; wherein, the piezoelectric drive unit includes at least one The first piezoelectric element on the surface of the structure, the asymmetric control circuit includes a first diode, a capacitor, and a first power switch tube, and the piezoelectric sensing unit includes at least one second sensor attached to the surface of the controlled structure. The piezoelectric element, the system circuit includes an extremum detection unit, an inductor, a switch unit, and a signal processing unit;

In the asymmetric control circuit: one pole of the first diode is connected to the first piezoelectric element, and the other pole is connected to one end of the capacitor; the other end of the capacitor is connected to the first piezoelectric element, and the first piezoelectric element is connected to the other end of the capacitor. A power switch tube is connected in parallel to both ends of the first diode, one end of the inductor is connected to the output end of the first piezoelectric element, the other end is connected to one end of the switch unit, and the other end of the switch unit is connected to the first piezoelectric element The input end of the element is connected; the input end of the extremum detection unit is connected to the second piezoelectric element, and the output end is connected to the switch unit; the input end of the signal processing unit is connected to the output signal of the extremum detection unit, the first piezoelectric element The output end of the voltage signal generated by the element is connected to the control electrode of the first power switch tube.

In the structural vibration semi-active control system based on an asymmetric control circuit, the switch unit includes: a second diode, a third diode, a second power switch tube, and a third power switch tube; wherein:

The anode of the second diode is connected to the cathode of the third diode, and the cathode is connected to one end of the second power switch tube; the other end of the second power switch tube is connected to one end of the third power switch tube, The other end of the third power switch tube is connected to the anode of the third diode.

In the structural vibration semi-active control system based on an asymmetric control circuit, the switch unit includes: a second diode, a third diode, a second power switch tube, a third power switch tube, a first voltage source, a second Two voltage sources; where:

The anode of the second diode is connected to the cathode of the third diode, and the cathode is connected to one end of the second power switch tube; the other end of the second power switch tube is connected to the negative pole of the first voltage source; the The anode of the first voltage source is connected to the cathode of the second voltage source; the anode of the second voltage source is connected to one end of the third power switch tube, and the other end of the third power switch tube is connected to the anode of the third diode .

The present invention adopts the above-mentioned technical scheme and has the following beneficial effects: the present invention utilizes an asymmetrical control circuit connected in parallel at both ends of the piezoelectric element to realize the asymmetric reversal of the voltage at both ends of the piezoelectric element, and expands the possibilities of the piezoelectric element in semi-active vibration control. The selected range, so that the structural vibration can be controlled more effectively, and has a wide application prospect in structural vibration control.

Description of drawings

Figure 1 is a schematic diagram of a semi-active control system for structural vibration based on an asymmetric control circuit.

FIG. 2 is a circuit diagram of the first embodiment.

Fig. 3 is a curve diagram of vibration displacement, voltage and velocity of the controlled structure in Embodiment 1.

FIG. 4 is a circuit diagram of the second embodiment.

Fig. 5 is a curve diagram of vibration displacement, voltage and speed of the controlled structure in the second embodiment. ``

Explanation of symbols in the figure: M1 and M2 are the first and second piezoelectric elements, K1 is the switch unit, L is the inductance, C is the capacitor, D1-D3 are the first to third diodes, S1-S3 are the first To the third power switch tube, U1 and U2 are the first and second DC voltage sources, 1 is the piezoelectric driving unit, 2 is the asymmetric control circuit, and 3 is the piezoelectric sensing unit.

Detailed ways

Below in conjunction with accompanying drawing, the technical scheme of invention is described in detail:

The structural vibration semi-active control system based on the asymmetric control circuit shown in Fig. 1 includes: a piezoelectric drive unit 1, an asymmetric control circuit 2, a piezoelectric sensing unit 3, and a system circuit. The piezoelectric drive unit 1 includes at least one first piezoelectric element M1 attached to the surface of the controlled structure, and the asymmetric control circuit 2 includes a first diode D1, a capacitor C, a first power switch S1, and a piezoelectric sensor Unit 3 includes at least one second piezoelectric element M2 attached to the surface of the structure to be controlled, and the system circuit includes an extremum detection unit, an inductor L, a switch unit K1, and a signal processing unit. The series branch composed of the first diode D1 and the capacitor C is connected in parallel to both ends of the first piezoelectric element M1, the first power switch tube S1 is connected in parallel to both ends of the first diode D1, and one end of the inductor L is connected to the first piezoelectric element M1. The output end of a piezoelectric element M1 is connected, the other end is connected with one end of the switch unit K1, the other end of the switch unit K1 is connected with the input end of the first piezoelectric element M1; the input end of the extremum detection unit is connected with the second piezoelectric element The component M2 is connected, and the output terminal is connected to the switch unit; the input terminal of the signal processing unit is connected to the output signal of the extreme value detection unit, the voltage signal generated by the first piezoelectric element (M1), and the output terminal is connected to the control of the first power switch tube S1 pole connection. The extreme value detection unit is a vibration displacement detection device and a computer measurement system, and the signal processing unit is a switch trigger circuit. The vibration displacement detection device converts the structural vibration displacement into a sensor signal, the computer measurement system monitors the extreme point of the sensor signal, and the square switch triggers the square wave signal of the circuit to generate the gate control signal of the power switch tube.

When the structure vibrates, the first piezoelectric element M1 and the second piezoelectric element M2 pre-arranged on the structure will generate a voltage signal due to the vibration induction of the structure, and since the two piezoelectric sheets are arranged at the same position, therefore Capable of sensing the same vibrating voltage signal. The first piezoelectric element M1 is used as a driver for vibration control, and the second piezoelectric element M2 is used as a sensor in the vibration control circuit. When the displacement of the structural vibration reaches the extreme value, the detection device for the extreme value of the structural vibration will output a control signal to the switch, and the switch in the loop is quickly closed. Since the first piezoelectric element M1 can generally be equivalent to a capacitor, the switch is closed At the same time, the piezoelectric element and the inductance L in the loop will undergo LC high-frequency resonance. When the resonance oscillates for half a cycle, the switch is quickly disconnected. At this time, the voltage on the first piezoelectric element M1 is reversed from that before the switch is closed. After the symmetrical control circuit, due to the action of the first diode, the energy generated when the controlled structure vibrates can only charge the capacitor in one direction, keep the first switch off, and only when the voltage across the first piezoelectric element M1 is changed by During the time when the negative extreme value becomes 0 or the voltage across the first piezoelectric element M1 changes from the positive extreme value to 0 (when the first diode is reversely connected to the circuit), the first power switch S1 is closed, Asymmetric reversal of the voltage at both ends of the first piezoelectric element M1 can be realized. When the switch unit K1 is turned off, the voltage generated on the first piezoelectric element M1 is in phase with the displacement of the structural vibration. When the displacement of the structural vibration reaches the extreme value again, the switch is turned on again, and after half a period of high-frequency oscillation Turn off the switch. The movement of the first power switch tube S1 and the switch unit K1 is controlled repeatedly so that the voltage generated on the first piezoelectric element M1 is always opposite to the direction of the structural vibration velocity, thereby achieving the purpose of vibration control.

In view of the fact that the SSDS method and the SSDNC technology do not involve voltage reversal, the present invention only illustrates the voltage reversal of SSDI and SSDV.

Specific embodiment one:

As shown in Figure 2, the structural vibration semi-active control system based on the asymmetric control circuit includes: a piezoelectric drive unit 1, an asymmetric control circuit 2, a piezoelectric sensing unit 3, and a system circuit. The piezoelectric drive unit 1 includes at least one first piezoelectric element M1 attached to the surface of the controlled structure, and the asymmetric control circuit 2 includes a first diode D1, a capacitor C, a first power switch S1, and a piezoelectric sensor Unit 3 includes at least one second piezoelectric element M2 attached to the surface of the structure to be controlled, and the system circuit includes an extremum detection unit, an inductor L, a switch unit K1, and a signal processing unit. The cathode of the first diode D1 is connected to the first piezoelectric element M1, the anode is connected to one end of the capacitor C, the other end of the capacitor C is connected to the first piezoelectric element M1, and the first power switch tube S1 is connected to the first two At both ends of the pole tube D1, one end of the inductance L is connected to the output end of the first piezoelectric element M1, the other end is connected to one end of the switch unit K1, and the other end of the switch unit K1 is connected to the input end of the first piezoelectric element M1; The input end of the extreme value detection unit is connected to the second piezoelectric element M2, and the output end is connected to the switch unit; the input end of the signal processing unit is connected to the output end of the extreme value detection unit, and the output end is connected to the control of the first power switch tube S1 pole connection. In addition, the first diode D1 and the capacitor C can also be connected in this way: the anode of the first diode D1 is connected to the first piezoelectric element M1, and the cathode is connected to one end of the capacitor C.

The switch unit K1 includes: a second diode D2, a third diode D3, a second power switch S2, and a third power switch S3. Wherein: the anode of the second diode D2 is connected to the cathode of the third diode D3, and the cathode is connected to one end of the second power switch tube S2; the other end of the second power switch tube S2 is connected to the third power switch tube S3 One end is connected, and the other end of the third power switch tube S3 is connected to the anode of the third diode D3. The connection point between the anode of the second diode D2 and the cathode of the third diode D3 is the terminal connecting the switch unit K1 to the inductor L, and the connection point between the second power switch tube S2 and the third power switch tube S3 is the switch A terminal to which the unit K1 is connected to the first piezoelectric element M1.

Specific example 1 can realize asymmetric SSDI technology, and the positive absolute value of the voltage reversal value is relatively large, and the negative absolute value is small. Specific embodiment 1 The vibration displacement, voltage and velocity curves of the controlled structure are shown in FIG. 3 .

The control process of specific embodiment 1: when the displacement of the cantilever beam changes from a negative maximum value to a positive maximum value, the first, second, and third power switch tubes S1, S2, and S3 are all turned off, and the first A piezoelectric element M1 is in the forward charging state, the first diode D1 is in the cut-off state, and the capacitor C is not in the charging state. The voltage across the first piezoelectric element M1 gradually reaches the positive extreme value, and the voltage across the capacitor C is not change; when the displacement reaches the positive maximum value, the second power switch S2 is closed, the first and third power switches S1 and S3 are turned off, the first diode D1 and the second diode D2 are turned on, The first piezoelectric element M1 and the inductance L form a high-frequency resonant circuit, the voltage at both ends of the first piezoelectric element M1 gradually becomes negative and reaches the maximum absolute value, the capacitor C is in a positive charging state, and the voltage at both ends gradually reaches a maximum value; after half a cycle of LC oscillation, the first, second, and third power switch tubes S1, S2, and S3 are all disconnected, the first piezoelectric element M1 is in a reverse charging state, and the first diode D1 is turned on. Capacitor C is in the positive charging state, the voltage across the first piezoelectric element M1 gradually reaches the reverse maximum value, and the voltage across capacitor C gradually reaches the positive maximum value; when the displacement reaches the negative maximum value, the first, The third power switch tubes S1 and S3 are closed, the second power switch tube S2 is turned off, the third diode D3 is turned on, the first piezoelectric element M1 and the inductor L form a high-frequency resonant circuit, and the first piezoelectric element M1 The capacitor C is reversely charged, the charge on the capacitor C is gradually neutralized, the voltage tends to a stable value, and the voltage at both ends of the first piezoelectric element M1 gradually becomes 0; when the voltage at both ends of the piezoelectric element becomes 0, the second The three power switch tube S3 is closed, the first and second power switch tubes S1 and S2 are both off, the third diode D3 is turned on, the first piezoelectric element M1 and the inductor L form a high-frequency resonant circuit, and the two piezoelectric elements The terminal voltage gradually increases, and when it reaches the maximum value, the third power switch S3 is turned off, and the voltage across the capacitor C remains unchanged.

Specific embodiment two:

As shown in Figure 4, the structural vibration semi-active control system based on the asymmetric control circuit includes: a piezoelectric drive unit 1, an asymmetric control circuit 2, a piezoelectric sensing unit 3, and a system circuit. The piezoelectric drive unit 1 includes at least one first piezoelectric element M1 attached to the surface of the controlled structure, and the asymmetric control circuit 2 includes a first diode D1, a capacitor C, a first power switch S1, and a piezoelectric sensor Unit 3 includes at least one second piezoelectric element M2 attached to the surface of the structure to be controlled, and the system circuit includes an extremum detection unit, an inductor L, a switch unit K1, and a signal processing unit. The anode of the first diode D1 is connected to the first piezoelectric element M1, the cathode is connected to one end of the capacitor C, the other end of the capacitor C is connected to the first piezoelectric element M1, and the first power switch tube S1 is connected to the first two At both ends of the pole tube D1, one end of the inductance L is connected to the output end of the first piezoelectric element M1, the other end is connected to one end of the switch unit K1, and the other end of the switch unit K1 is connected to the input end of the first piezoelectric element M1; The input end of the extreme value detection unit is connected to the second piezoelectric element M2, and the output end is connected to the switch unit; the input end of the signal processing unit is connected to the output end of the extreme value detection unit, and the output end is connected to the control of the first power switch tube S1 pole connection. In addition, the first diode D1 and the capacitor C can also be connected in this way: the cathode of the first diode D1 is connected to the first piezoelectric element M1, and the anode is connected to one end of the capacitor C.

The switch unit K1 includes: a second diode D2, a third diode D3, a second power switch S2, a third power switch S3, a first voltage source U1, and a second voltage source U2. The anode of the second diode D2 is connected to the cathode of the third diode D3, and the cathode is connected to one end of the second power switch tube S2; the other end of the second power switch tube S2 is connected to the negative pole of the first voltage source U1; The anode of a voltage source U1 is connected to the cathode of the second voltage source U2; the anode of the second voltage source U2 is connected to one end of the third power switch S3, and the other end of the third power switch S3 is connected to the anode of the third diode D3 connect. The connection point between the anode of the second diode D2 and the cathode of the third diode D3 is the terminal where the switch unit K1 is connected to the inductor L, and the connection point between the positive pole of the first voltage source U1 and the negative pole of the second voltage source U2 is the switch A terminal to which the unit K1 is connected to the first piezoelectric element M1.

Specific example 2 can realize asymmetric SSDV technology, and the negative absolute value of the voltage reversal value is larger, and the positive absolute value is smaller.

The control process of the second specific embodiment: when the displacement of the cantilever beam changes from a positive maximum value to a negative maximum value, the first, second, and third power switch tubes S1, S2, and S3 are all disconnected, and the first A piezoelectric element M1 is in a reverse charging state, the first diode D1 is in a cut-off state, and the capacitor C is not in a charging state, the voltage at both ends of the first piezoelectric element M1 gradually reaches a negative extreme value, and the voltage at both ends of the capacitor C is constant. change; when the displacement reaches the negative maximum value, the third power switch S3 is closed, the first and second power switch S1, S2 are turned off, the first diode D1 and the third diode D3 are turned on, The first piezoelectric element M1 and the inductance L form a high-frequency resonant circuit, the voltage at both ends of the first piezoelectric element M1 gradually becomes positive and reaches the maximum absolute value, the capacitor C is in a state of reverse charging, and the voltage at both ends gradually reaches a maximum value; after half a period of LC oscillation, the first, second, and third power switch tubes S1, S2, and S3 are all disconnected, the first piezoelectric element M1 is in a forward charging state, and the first diode D1 is turned on. Capacitor C is in the state of reverse charging, the voltage at both ends of the first piezoelectric element M1 gradually reaches the positive maximum value, and the voltage at both ends of the capacitor C gradually reaches the reverse maximum value; when the displacement reaches the positive maximum value, the first, The second power switch tubes S1 and S2 are closed, the third power switch tube S3 is turned off, the second diode D2 is turned on, the first piezoelectric element M1 and the inductor L form a high-frequency resonant circuit, and the first piezoelectric element M1 The capacitor C is positively charged, the charge on the capacitor C is gradually neutralized, the voltage tends to a stable value, and the voltage at both ends of the first piezoelectric element M1 gradually becomes 0; when the voltage at both ends of the piezoelectric element becomes 0, the second The second power switch tube S2 is closed, the first and third power switch tubes S1 and S3 are both off, the second diode D2 is turned on, the first piezoelectric element M1 and the inductor L form a high-frequency resonant circuit, and the two piezoelectric elements The terminal voltage gradually increases, and when it reaches the maximum value, the second power switch S2 is turned off, and the voltage across the capacitor C remains unchanged.

To sum up, the structural vibration semi-active control system based on the asymmetric control circuit of the present invention utilizes the parallel connection of the asymmetric control circuit at both ends of the piezoelectric element to realize the asymmetric reversal of the voltage at both ends of the piezoelectric element, expanding the semi-active The optional range of piezoelectric elements in active vibration control can control structural vibration more effectively, and has a wide application prospect in structural vibration control.

Claims (3)

1. A structural vibration semi-active control system based on an asymmetric control circuit, characterized in that it includes: a piezoelectric drive unit (1), an asymmetric control circuit (2), a piezoelectric sensing unit (3), and a system circuit; wherein, The piezoelectric drive unit (1) includes at least one first piezoelectric element (M1) attached to the surface of the controlled structure, and the asymmetric control circuit (2) includes a first diode (D1), a capacitor ( C), the first power switch tube (S1), the piezoelectric sensing unit (3) includes at least one second piezoelectric element (M2) attached to the surface of the controlled structure, and the system circuit includes extreme value detection Unit, inductor (L), switch unit (K1), signal processing unit; In the asymmetric control circuit (2): one pole of the first diode (D1) is connected to the first piezoelectric element * (M1), and the other pole is connected to one end of the capacitor (C); the capacitor ( C) The other end is connected to the first piezoelectric element (M1), the first power switch tube (S1) is connected to both ends of the first diode (D1), and one end of the inductor (L) is connected to the first The output end of a piezoelectric element (M1) is connected, the other end is connected with one end of the switch unit (K1), and the other end of the switch unit (K1) is connected with the input end of the first piezoelectric element (M1); the extremum The input end of the detection unit is connected to the second piezoelectric element (M2), and the output end is connected to the switch unit; the input end of the signal processing unit is connected to the output signal of the extremum detection unit and the voltage generated by the first piezoelectric element (M1) signal, and the output terminal is connected to the control pole of the first power switch tube (S1). 2. The structural vibration semi-active control system based on an asymmetric control circuit according to claim 1, characterized in that the switch unit (K1) includes: a second diode (D2), a third diode (D3 ), the second power switch tube (S2), and the third power switch tube (S3); where: The anode of the second diode (D2) is connected to the cathode of the third diode (D3), and the cathode is connected to one end of the second power switch tube (S2); the second power switch tube (S2) The other end is connected to one end of the third power switch tube (S3), and the other end of the third power switch tube (S3) is connected to the anode of the third diode (D3). 3. The structural vibration semi-active control system based on an asymmetric control circuit according to claim 1, characterized in that the switch unit (K1) includes: a second diode (D2), a third diode (D3 ), the second power switch tube (S2), the third power switch tube (S3), the first voltage source (U1), and the second voltage source (U2); among them: The anode of the second diode (D2) is connected to the cathode of the third diode (D3), and the cathode is connected to one end of the second power switch tube (S2); the second power switch tube (S2) The other end is connected to the negative pole of the first voltage source (U1); the positive pole of the first voltage source (U1) is connected to the negative pole of the second voltage source (U2); the positive pole of the second voltage source (U2) is connected to the third power switch One end of the tube (S3) is connected, and the other end of the third power switch tube (S3) is connected to the anode of the third diode (D3).

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