Power supply grounding monitoring device for direct-current floating power supply system

Abstract

The utility model belongs to the technical field of electronic circuits, and particularly discloses a power supply grounding monitoring device for a direct current floating power supply system, which comprises a monitoring host and a direct current leakage analyzer, and is characterized in that the monitoring host is provided with a data acquisition module, a processor, an information display module, an alarm output module, a communication unit and a pulse generation module; the processor is respectively connected with the data acquisition module, the information display module, the alarm output module, the communication unit and the pulse generation module, the communication unit is in communication connection with the direct-current leakage analyzer, and the data acquisition module is linked with a power supply loop of the direct-current floating power supply system. According to the utility model, continuous, unmanned and high-efficiency power supply grounding monitoring of the direct-current floating power supply system can be realized, the power supply grounding condition of the direct-current floating power supply system can be accurately reflected, and support is provided for judging the grounding degree and the grounding property.

Description

Technical Field

[0001] The utility model belongs to the technical field of electronic circuits, and in particular relates to a power grounding monitoring device for a DC floating power supply system. Background Art

[0002] In the field of automatic control, in order to improve the reliability of low-voltage DC power supply, more and more DC systems use a power supply method in which the negative pole of the power supply is not grounded, that is, a DC floating power supply method. This floating power supply method can effectively ensure the continuity of power supply for single-end grounding events (such as short circuits and leakage) that are very likely to occur on site. Figure 1 As shown in the figure, it is a typical DC floating power supply system, the power supply voltage is U, and the positive and negative poles are not grounded. A pair of high-resistance balancing resistors R1 and R2 are connected between the positive and negative poles of the power supply to the ground, and the positive and negative poles to the ground voltages U1 and U2 can be obtained to monitor the power supply grounding. When the power supply is not grounded, the voltage across the resistor R1 is U1 = U / 2, and the voltage across the resistor R2 is U2 = U / 2; when the negative pole of the power supply is grounded, corresponding to the grounding degree from weak to strong (leakage to short circuit), the voltage across the resistor R1 U1 changes from U / 2 to U, and the voltage across the resistor R2 U2 changes from U / 2 to 0; when the positive pole of the power supply is grounded, corresponding to the grounding degree from weak to strong (leakage to short circuit), the voltage across the resistor R1 U1 changes from U / 2 to 0, and the voltage across the resistor R2 U2 changes from U / 2 to U.

[0003] Therefore, in the floating power supply mode, when a single-end grounding event occurs in the DC power supply, the power supply voltage U remains unchanged, thereby ensuring the continuity of power supply. However, after the grounding occurs, it must be handled in time, otherwise the fault will be delayed from single-point grounding to multiple-point grounding of the positive and negative poles, resulting in errors in the acquisition of switching / analog quantities, affecting the safe operation of the system and the accuracy of measurement. More seriously, it will cause malfunction of the switching / analog output, thereby causing production accidents. At present, the monitoring of the power supply grounding condition of the DC floating power supply system is usually completed by manual testing, which is very inefficient and cannot achieve uninterrupted real-time monitoring. Utility Model Content

[0004] The utility model aims to provide a power grounding monitoring device for a DC floating power supply system, so as to solve the above problems existing in the prior art.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides a power grounding monitoring device for a DC floating power supply system, comprising a monitoring host, wherein a data acquisition module, a processor, an information display module and an alarm output module are arranged inside the monitoring host, wherein the processor is respectively connected to the data acquisition module, the information display module and the alarm output module, wherein the data acquisition module is connected to a power supply circuit of the DC floating power supply system, and is used for collecting a voltage monitoring signal and a current monitoring signal of the power supply circuit of the DC floating power supply system, and transmitting the voltage signal and the current signal to the processor, wherein the processor is used for receiving the voltage monitoring signal and the current monitoring signal, and outputting the monitoring voltage information and the monitoring current information to the information display module, and is used for outputting an alarm control signal to the alarm output module, wherein the information display module is used for displaying the monitoring voltage information and the monitoring current information, and wherein the alarm output module is used for sending an alarm message after receiving the alarm control signal.

[0007] In one possible design, the device also includes a DC leakage analyzer, and the monitoring host also includes a communication unit and a pulse generating module. The communication unit and the pulse generating module are both electrically connected to the processor, and the communication unit establishes a communication connection with the DC leakage analyzer. The pulse generating module is connected to the power supply circuit of the DC floating power supply system. The DC leakage analyzer is used to send a detection signal to the communication unit, and the communication unit is used to transmit the detection signal to the processor. The processor is used to send a pulse control signal to the pulse generating module according to the detection signal. The pulse generating module is connected to the power supply circuit of the DC floating power supply system, and is used to input a test pulse signal to the power supply circuit of the DC floating power supply system according to the pulse control signal. The DC leakage analyzer is used to collect the test pulse signal of the power supply circuit of the DC floating power supply system for leakage detection.

[0008] In a possible design, a switch protection circuit is provided on the line between the processor and the communication unit and the pulse generating module, and the switch protection circuit is used to control the access or exit of the communication unit and the access or exit of the pulse generating module.

[0009] In one possible design, the switch protection circuit includes a relay and a safety switch, wherein the relay is used to control the access or exit of the communication unit and the access or exit of the pulse generating module, and the safety switch is arranged on the power supply line of the relay.

[0010] In a possible design, the DC leakage analyzer is provided with a caliper-type sensor for collecting a test pulse signal of a power supply circuit of a DC floating power supply system.

[0011] In a possible design, the communication unit uses a wireless communication module, and the communication unit establishes a wireless communication connection with the DC leakage analyzer.

[0012] In one possible design, the pulse generating module includes a pulse signal generator.

[0013] In a possible design, the processor is a single-chip microcomputer, and the alarm output module includes an indicator light and a buzzer.

[0014] Beneficial effects: The utility model can realize continuous, unmanned, and efficient power grounding monitoring of the DC floating power supply system, accurately reflect the power grounding status of the DC floating power supply system, and provide support for judging the grounding degree and grounding nature. The utility model can detect and coordinate the power grounding status of the DC floating power supply system through wireless data communication, and realize rapid detection and positioning of the grounding line. The utility model can realize the on-off control of the communication end and the pulse generating end through the switch protection circuit, which greatly improves the safety of the device itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a circuit diagram of an existing DC floating power supply system;

[0017] Figure 2 A schematic diagram of a circuit of a device provided in an embodiment of the utility model;

[0018] Figure 3 Schematic diagram of a switch protection circuit in an embodiment of the present utility model. DETAILED DESCRIPTION

[0019] It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. The specific structural and functional details disclosed herein are only used to describe the exemplary embodiments of the present invention. However, the present invention can be embodied in many alternative forms, and it should not be understood that the present invention is limited to the embodiments described herein.

[0020] It should be understood that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments can be understood according to specific circumstances.

[0021] In the following description, certain details are provided to facilitate a complete understanding of the example embodiments. However, it will be appreciated by those of ordinary skill in the art that the example embodiments may be implemented without these certain details. For example, the system may be shown in a block diagram to avoid obscuring the example with unnecessary details. In other embodiments, well-known processes, structures, and techniques may not be shown in unnecessary detail to avoid obscuring the embodiments.

[0022] Example:

[0023] This embodiment provides a power grounding monitoring device for a DC floating power supply system, such as Figure 2 As shown, it includes a monitoring host, and a data acquisition module, a processor, an information display module and an alarm output module are arranged inside the monitoring host. The processor is connected to the data acquisition module, the information display module and the alarm output module respectively. The data acquisition module is connected to the power supply circuit of the DC floating power supply system, and is used to collect the voltage monitoring signal and the current monitoring signal of the power supply circuit of the DC floating power supply system, and transmit the voltage signal and the current signal to the processor. The processor is used to receive the voltage monitoring signal and the current monitoring signal, and output the monitoring voltage information and the monitoring current information to the information display module, and is used to output the alarm control signal to the alarm output module. The information display module is used to display the monitoring voltage information and the monitoring current information, and the alarm output module is used to send out the alarm information after receiving the alarm control signal.

[0024] In specific implementation, the monitoring host can be installed at the power supply end of the DC floating power supply system, and the data acquisition module can be connected to the positive / negative power supply circuit of the DC floating power supply system. The voltage monitoring signal and current monitoring signal on the positive / negative power supply circuit of the DC floating power supply system are collected through the data acquisition module, and the voltage signal and current signal are transmitted to the processor, and the processor processes the voltage monitoring signal and the current monitoring signal, determines the voltage and current on the positive / negative power supply circuit of the DC floating power supply system according to the voltage monitoring signal and the current monitoring signal, and outputs the monitoring voltage information and the monitoring current information to the information display module, and the display module displays the monitoring voltage information and the monitoring current information. At the same time, when the processor determines that the voltage and current on the positive / negative power supply circuit of the DC floating power supply system are abnormal, it outputs an alarm control signal to the alarm output module, and the alarm output module sends corresponding alarm information after receiving the alarm control signal. The processor and operation and maintenance personnel can judge the grounding nature and grounding degree according to the monitoring voltage information and monitoring current information displayed by the display module. For example, taking the monitoring voltage information of the positive end of the DC floating power supply system as an example, the relationship between the voltage displayed by the display module and the corresponding grounding nature and grounding degree can be shown in the following table 1:

[0025] Table 1

[0026] Display voltage Grounding properties Grounding degree 01 0V Positive ground Short circuit to ground 02 2V Positive ground Strong grounding 03 4V Positive ground Grounding 04 6V Positive ground Grounding 05 8V Positive ground Weak grounding 06 10V Positive ground Weak grounding 07 12V Ungrounded Ungrounded 08 14V Negative ground Weak grounding 09 16V Negative ground Weak grounding 10 18V Negative ground Grounding 11 20V Negative ground Grounding 12 22V Negative ground Strong grounding 13 24V Negative ground Short circuit to ground

[0027] When the monitored voltage at the positive terminal of the DC floating power supply system is 12V, it indicates that there is no ground fault; when the monitored voltage at the positive terminal of the DC floating power supply system is 0V, it indicates that the positive pole is short-circuited to the ground; when the monitored voltage at the positive terminal of the DC floating power supply system is 24V, it indicates that the negative pole is short-circuited to the ground, and so on.

[0028] Furthermore, the device also includes a DC leakage analyzer, and the monitoring host also includes a communication unit and a pulse generating module. The communication unit and the pulse generating module are both electrically connected to the processor, and the communication unit establishes a communication connection with the DC leakage analyzer, the pulse generating module is connected to the power supply circuit of the DC floating power supply system, the DC leakage analyzer is used to send a detection signal to the communication unit, the communication unit is used to transmit the detection signal to the processor, the processor is used to send a pulse control signal to the pulse generating module according to the detection signal, the pulse generating module is connected to the power supply circuit of the DC floating power supply system, and is used to input a test pulse signal to the power supply circuit of the DC floating power supply system according to the pulse control signal, and the DC leakage analyzer is used to collect the test pulse signal of the power supply circuit of the DC floating power supply system for leakage detection.

[0029] The monitoring host establishes a communication connection with the DC leakage analyzer through the communication unit. When the processor detects a grounding fault and needs to further locate the grounding fault, the DC leakage analyzer can send a detection signal to the processor. The processor sends a pulse control signal to the pulse generating module according to the detection signal. The test pulse signal is input to the power supply circuit of the DC floating power supply system through the pulse generating module. The DC leakage analyzer then captures the weak test pulse signal of the power supply circuit of the DC floating power supply system through a caliper sensor for leakage detection. After corresponding pulse signal analysis, the grounding line can be quickly located.

[0030] Furthermore, a switch protection circuit is provided on the line between the processor and the communication unit and the pulse generating module, and the switch protection circuit is used to control the access or exit of the communication unit and the access or exit of the pulse generating module. Figure 3 As shown, the switch protection circuit includes a relay and a safety switch, the relay is used to control the access or exit of the communication unit, and the access or exit of the pulse generating module, and the safety switch is arranged on the power supply line of the relay. When the device is monitoring, the safety switch K is disconnected, the relay J does not work, and the electronic switch composed of the field effect tubes Q1 and Q2 is used to control the operation of the pulse generating module. At this time, the ground path of Q1 and Q2 is cut off, and the pulse generating module cannot be controlled to work. The communication unit used for wireless data transmission is also cut off from power, and the indicator light is on, indicating that the device is in a safe state. In the safe state, the pulse generating module and the communication unit are completely isolated, so that even if the device is damaged, it will not cause any adverse effect on the operation of the DC floating power supply system. When it is necessary to connect to the DC leakage analyzer for grounding positioning, the processor controls the safety switch K to close according to the detection signal, the relay J acts, the grounding path of the electronic switches Q1 and Q2 is connected, the pulse generating module is controlled to work, and the power supply of the communication unit is also connected, and the indicator light is off, indicating that the device is in a test state. In the test state, the monitoring host can communicate data with the DC leakage analyzer, and the detection results of the DC leakage analyzer can be fed back to the monitoring host for display.

[0031] Furthermore, the communication unit may adopt a wireless communication module, and the communication unit establishes a wireless communication connection with the DC leakage analyzer. The pulse generating module includes a pulse signal generator to generate a test pulse signal through the pulse signal generator. The processor adopts a single-chip microcomputer, and the alarm output module includes an indicator light and a buzzer, which can be used to issue an audible and visual alarm message.

[0032] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A power grounding monitoring device for a DC floating power supply system, characterized in that: The monitoring host comprises a monitoring host, wherein a data acquisition module, a processor, an information display module and an alarm output module are arranged inside the monitoring host, the processor is respectively connected to the data acquisition module, the information display module and the alarm output module, the data acquisition module is connected to the power supply circuit of the DC floating power supply system, and is used to collect the voltage monitoring signal and the current monitoring signal of the power supply circuit of the DC floating power supply system, and transmit the voltage signal and the current signal to the processor, the processor is used to receive the voltage monitoring signal and the current monitoring signal, and output the monitoring voltage information and the monitoring current information to the information display module, and is used to output the alarm control signal to the alarm output module, the information display module is used to display the monitoring voltage information and the monitoring current information, and the alarm output module is used to send out the alarm information after receiving the alarm control signal.

2. A DC floating power supply system power grounding monitoring device according to claim 1, characterized in that: The device also includes a DC leakage analyzer, and the monitoring host also includes a communication unit and a pulse generating module. The communication unit and the pulse generating module are both electrically connected to the processor, and the communication unit establishes a communication connection with the DC leakage analyzer. The pulse generating module is connected to the power supply circuit of the DC floating power supply system. The DC leakage analyzer is used to send a detection signal to the communication unit, and the communication unit is used to transmit the detection signal to the processor. The processor is used to send a pulse control signal to the pulse generating module according to the detection signal. The pulse generating module is connected to the power supply circuit of the DC floating power supply system and is used to input a test pulse signal to the power supply circuit of the DC floating power supply system according to the pulse control signal. The DC leakage analyzer is used to collect the test pulse signal of the power supply circuit of the DC floating power supply system for leakage detection.

3. A DC floating power supply system power grounding monitoring device according to claim 2, characterized in that: A switch protection circuit is provided on the line between the processor and the communication unit and the pulse generating module, and the switch protection circuit is used to control the access or exit of the communication unit and the access or exit of the pulse generating module.

4. A DC floating power supply system power grounding monitoring device according to claim 3, characterized in that: The switch protection circuit includes a relay and a safety switch. The relay is used to control the access or exit of the communication unit and the access or exit of the pulse generating module. The safety switch is arranged on the power supply line of the relay.

5. The power grounding monitoring device for a DC floating power supply system according to claim 2, characterized in that: The DC leakage analyzer is provided with a caliper-type sensor for collecting a test pulse signal of a power supply circuit of a DC floating power supply system.

6. A DC floating power supply system power grounding monitoring device according to claim 2, characterized in that: The communication unit adopts a wireless communication module, and the communication unit establishes a wireless communication connection with the DC leakage analyzer.

7. A DC floating power supply system power grounding monitoring device according to claim 2, characterized in that: The pulse generating module comprises a pulse signal generator.

8. The power grounding monitoring device for a DC floating power supply system according to claim 1, characterized in that: The processor is a single chip microcomputer, and the alarm output module includes an indicator light and a buzzer.

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