阅读说明：本技术 一种抗干扰雷击电流检测装置 (Anti-interference lightning current detection device ) 是由 赵湘文 丁佳钰 邱小灵 林武汉 聂进培 冯学松 谢子亮 于 2021-01-26 设计创作，主要内容包括：本发明公开一种抗干扰雷击电流检测装置,包括依次连接的电荷积分电路、运放电路和AD转换电路；电荷积分电路用于接收电流传感器获取的雷电流模拟信号,并输出真实电流模拟信号；运放电路用于接收真实电流模拟信号,并输出高倍数电流模拟信号；AD转换电路用于获取高倍数电流模拟信号,并输出雷电流数字信号。本发明的有益效果是：通过电荷积分电路、运放电路和AD转换电路的设置,抑制干扰信号,还原真实雷电流信号,提高了雷电流监测的准确性。(The invention discloses an anti-interference lightning current detection device, which comprises a charge integrating circuit, an operational amplifier circuit and an AD conversion circuit which are connected in sequence; the charge integration circuit is used for receiving the lightning current analog signal acquired by the current sensor and outputting a real current analog signal; the operational amplifier circuit is used for receiving the real current analog signal and outputting a high-multiple current analog signal; the AD conversion circuit is used for acquiring high-multiple current analog signals and outputting lightning current digital signals. The invention has the beneficial effects that: through the arrangement of the charge integrating circuit, the operational amplifier circuit and the AD conversion circuit, interference signals are suppressed, real lightning current signals are restored, and accuracy of lightning current monitoring is improved.)

1. An anti-interference lightning current detection device is characterized by comprising a charge integrating circuit, an operational amplifier circuit and an AD conversion circuit which are sequentially connected; the charge integration circuit is used for receiving the lightning current analog signal acquired by the current sensor and outputting a real current analog signal; the operational amplifier circuit is used for receiving the real current analog signal and outputting a high-multiple current analog signal; the AD conversion circuit is used for acquiring the high-multiple current analog signal and outputting a lightning current digital signal.

2. The apparatus of claim 1, wherein said charge integration circuit is an RC integration circuit.

3. The apparatus of claim 1, wherein the operational amplifier circuit is a differential amplifier circuit.

4. The apparatus of claim 1, wherein the AD conversion circuit is an analog-to-digital converter (ADC).

5. The apparatus according to claim 2, wherein the RC integrator circuit is an integrated IC, a power supply terminal of the integrated IC is connected to a 3.7V dc voltage source, the 3.7V dc voltage source is connected to an analog ground AGND through a capacitor C29, a ground terminal of the integrated IC is connected to an analog ground AGND, an inverting input terminal of the integrated IC is connected to one end of a resistor R42, a non-inverting input terminal of the integrated IC is connected to one end of a resistor R37, the other end of the resistor R37 is connected to an L2 terminal of the current transformer capacitor CT1, an L1 terminal of the current transformer capacitor CT1 is connected to the other end of the resistor R42, three parallel branches are provided between paths formed by the resistor R42, the resistor R37 and the current transformer capacitor CT1, a first parallel branch is provided with a transient suppression diode, a second parallel branch is provided with a capacitor C31, and one end of the capacitor C31 is connected to a 1.5V dc voltage source, the third parallel branch is for setting up resistance R11, resistance R11 with passageway between the 1.5V direct current voltage source inserts parallelly connected electric capacity C33's one end and polarity electric capacity E9 respectively, electric capacity C33's the other end and the negative pole of polarity electric capacity E9 are connected with analog ground AGND, integrated IC's non inverting input end with passageway between the resistance R37 receives 1.5V direct current voltage source through resistance R0, resistance R37 with be equipped with adjustable electric capacity CT between current transformer electric capacity CT 1's the L1 end, integrated IC's inverting input end is connected with integrated IC's output through resistance R41.

6. The tamper resistant lightning strike current detection device of claim 5, wherein the transient suppression diode is an SMBJ6.5CA-TVS transient suppression diode.

Technical Field

The invention relates to the technical field of lightning current detection, in particular to an anti-interference lightning current detection device.

Background

In the operation of an electric power system, a line arrester is one kind of electrical equipment for protecting the system from lightning disasters, and zinc oxide has excellent nonlinear characteristics and better performance indexes in various aspects such as current capacity and the like than the original silicon carbide, so the zinc oxide arrester gradually replaces the silicon carbide arrester to become important equipment for protecting the equipment from lightning damages in the electric power system. However, when the lightning arrester is aged and affected by moisture, the internal zinc oxide will be degraded to damage the performance of the lightning arrester, and the operation condition of the lightning arrester will directly influence the safe operation of the power system. In order to grasp the operation condition of the lightning arrester in time and ensure the safe and reliable operation of the power system, it is very necessary to carry out intelligent online monitoring and diagnosis on the lightning arrester.

At present, the traditional lightning current collecting device is mostly used for recording information such as time of occurrence of lightning stroke, amplitude of lightning current, energy and the like, cannot reproduce the waveform of a lightning current signal, and is not beneficial to a user to carry out more detailed research on lightning. The existing arrester monitoring terminal is in a working state all the time when running, and if no effective signal is triggered, data is continuously acquired and only reported regularly within a set period time, and redundant data can be automatically discarded. When lightning strike happens, the generated lightning current signal triggers a storage system of the acquisition device and records the lightning current signal. However, the interference of the environment of the working area of the lightning current collecting device is usually serious, the external interference signal often triggers the device to malfunction, and since the device itself cannot distinguish whether the collected signal is an external noise signal or a lightning current signal, the interference signal is often mistaken for the lightning current signal and is completely stored and uploaded to the platform, which not only causes the monitoring data recorded by the platform to be disordered, but also causes that the real lightning current signal cannot be distinguished due to the wrong recording, so that the real lightning current signal is omitted. It is not beneficial for the user to study the lightning in more detail.

Disclosure of Invention

Aiming at the problems, the invention provides an anti-interference lightning current detection device, which mainly solves the problems that the existing lightning current acquisition device cannot reproduce the waveform of a lightning current signal and is easy to generate misoperation.

In order to solve the technical problems, the technical scheme of the invention is as follows:

an anti-interference lightning current detection device comprises a charge integrating circuit, an operational amplifier circuit and an AD conversion circuit which are connected in sequence; the charge integration circuit is used for receiving the lightning current analog signal acquired by the current sensor and outputting a real current analog signal; the operational amplifier circuit is used for receiving the real current analog signal and outputting a high-multiple current analog signal; the AD conversion circuit is used for acquiring the high-multiple current analog signal and outputting a lightning current digital signal.

In some embodiments, the charge integration circuit is an RC integration circuit.

In some embodiments, the operational amplifier circuit is a differential amplifier circuit.

In some embodiments, the AD conversion circuit is an analog-to-digital converter ADC.

In some embodiments, the RC integrating circuit is an integrated IC, a power supply terminal of the integrated IC is connected to a 3.7V dc voltage source, the 3.7V dc voltage source is connected to an analog ground AGND through a capacitor C29, a ground terminal of the integrated IC is connected to the analog ground AGND, an inverting input terminal of the integrated IC is connected to one end of a resistor R42, a non-inverting input terminal of the integrated IC is connected to one end of a resistor R37, the other end of the resistor R37 is connected to an L2 terminal of the current transformer capacitor CT1, an L1 terminal of the current transformer capacitor CT1 is connected to the other end of the resistor R42, three parallel branches are provided between a path formed by the resistor R42, the resistor R37 and the current transformer capacitor CT1, a first parallel branch is provided with a transient suppression diode, a second parallel branch is provided with a capacitor C31, one end of the capacitor C31 is connected to a 1.5V dc voltage source, a third parallel branch is provided with a resistor R11, the circuit between the resistor R11 and the 1.5V direct current voltage source is respectively connected with one end of a capacitor C33 and a polar capacitor E9 which are connected in parallel, the other end of the capacitor C33 and the negative electrode of the polar capacitor E9 are connected with an analog ground AGND, the circuit between the non-inverting input end of the integrated IC and the resistor R37 is connected with the 1.5V direct current voltage source through a resistor R0, an adjustable capacitor CT is arranged between the resistor R37 and the L1 end of the current transformer capacitor CT1, and the inverting input end of the integrated IC is connected with the output end of the integrated IC through a resistor R41.

In some embodiments, the transient suppression diode is an SMBJ6.5CA-TVS transient suppression diode.

The invention has the beneficial effects that: through the arrangement of the charge integrating circuit, the operational amplifier circuit and the AD conversion circuit, interference signals are suppressed, real lightning current signals are restored, and accuracy of lightning current monitoring is improved.

Drawings

FIG. 1 is a schematic diagram of an anti-interference lightning strike current detection apparatus disclosed in an embodiment of the present invention;

fig. 2 is a circuit diagram of the RC integrating circuit disclosed in the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the following detailed description of the present invention is provided with reference to the accompanying drawings and detailed description. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings.

As shown in fig. 1, the present embodiment provides an anti-interference lightning current detection device, which includes a charge integration circuit, an operational amplifier circuit, and an AD conversion circuit, which are connected in sequence; the charge integration circuit is used for receiving the lightning current analog signal acquired by the current sensor and outputting a real current analog signal; the operational amplifier circuit is used for receiving the real current analog signal and outputting a high-multiple current analog signal; the AD conversion circuit is used for acquiring high-multiple current analog signals and outputting lightning current digital signals.

According to the invention, through the arrangement of the charge integrating circuit, the operational amplifier circuit and the AD conversion circuit, interference signals are inhibited, real lightning current signals are restored, and the accuracy of lightning current monitoring is improved.

Further, the charge integration circuit is an RC integration circuit. A passive RC network is a resistor in series with a capacitor, which is a fixed resistance in series with a capacitor that has a frequency dependent reactance that decreases as the frequency on its board increases. Therefore, at low frequencies, the reactance Xc of the capacitor is high, and at high frequencies, the reactance Xc is low due to the standard capacitive reactance equation of 1/(2 pi fC), and corresponds to a low-pass filter, and the differential signal output by the rogowski current sensor (abbreviated as rogowski coil) is added with the RC integral current to restore the true current signal.

Furthermore, the operational amplifier circuit is a differential amplifier circuit. The differential amplifier circuit is used for amplifying differential mode input signals and inhibiting common mode input signals. When the differential mode signal is input, the signals of the two differential amplifier input ends are equal in magnitude and opposite in polarity, so that the current increments of the differential pair transistors are equal in magnitude and opposite in polarity, voltage increments of the two output ends to the ground are caused, namely the differential mode output voltages are equal in magnitude and opposite in polarity, and the differential mode input signal is effectively amplified. When a common mode signal is input, signals of the two differential amplifier input ends are equal in size and same in polarity, so that current increments of the differential pair transistors are equal in size and same in polarity, voltage increments of the two output ends to the ground are caused, namely differential mode output voltages are equal in size and same in polarity, the differential pair transistor differential amplifier circuit has strong inhibition capacity on the common mode input signal, and influences, such as temperature noise and the like, brought to a circuit by changes of external conditions can be inhibited.

Specifically, the AD conversion circuit is an analog-to-digital converter ADC.

As shown in fig. 2, there is provided a preferred RC integrating circuit, the RC integrating circuit uses an integrated IC, a power supply terminal of the integrated IC is connected to a 3.7V dc voltage source, the 3.7V dc voltage source is connected to an analog ground AGND through a capacitor C29, a ground terminal of the integrated IC is connected to an analog ground AGND, an inverting input terminal of the integrated IC is connected to one end of a resistor R42, a non-inverting input terminal of the integrated IC is connected to one end of a resistor R37, the other end of the resistor R37 is connected to an L2 terminal of a current transformer capacitor CT1, an L1 terminal of a current transformer capacitor CT1 is connected to the other end of a resistor R42, three parallel branches are provided between a path formed by the resistor R42, the resistor R37 and the current transformer capacitor CT1, a first parallel branch is provided with a transient suppression diode, a second parallel branch is provided with a capacitor C31, one end of the capacitor C31 is connected to a 1.5V dc voltage source, a third parallel branch is provided with, the path between the resistor R11 and the 1.5V direct-current voltage source is respectively connected to one end of a capacitor C33 and a polar capacitor E9 which are connected in parallel, the other end of the capacitor C33 and the negative electrode of the polar capacitor E9 are connected with an analog ground AGND, the path between the non-inverting input end of the integrated IC and the resistor R37 is connected to the 1.5V direct-current voltage source through a resistor R0, an adjustable capacitor CT is arranged between the resistor R37 and the L1 end of the current transformer capacitor CT1, and the inverting input end of the integrated IC is connected with the output end of the integrated IC through a resistor R41.

The transient suppression diode is an SMBJ6.5CA-TVS transient suppression diode.

The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention accordingly, and not to limit the protection scope of the present invention accordingly. All equivalent changes or modifications made in accordance with the spirit of the present disclosure are intended to be covered by the scope of the present disclosure.