Remote signaling power supply device and method for automatically isolating insulation fault of measurement and control device

Abstract

The invention discloses a remote signaling power supply device and method for automatically isolating an insulation fault of a measurement and control device, and relates to the technical field of insulation fault processing, and the device comprises an MCU, an alarm module, a display module, an output insulation detection module, a control circuit, a DC contactor, and a DC / DC isolation power supply. The alarm module, the display module, the control circuit, the output insulation detection module and the DC / DC isolation power supply are respectively in communication connection with the MCU, the output insulation detection module and the DC contactor are also electrically connected with the control circuit, the output insulation detection module is used for measuring and controlling the insulation fault of the device, and the DC contactor controls the on-off of the DC power supply; and the DC / DC isolation power supply also supplies power to the measurement and control device in an isolation manner. Power supply of the measurement and control device can be guaranteed, an insulation fault is isolated from a direct current system, and safe operation of the direct current system is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of insulation fault processing, and in particular to a remote signaling power supply device and method for automatically isolating insulation faults of a measurement and control device. Background Art

[0002] Substation telemetering and control devices are one of the areas where insulation failures are common. The measurement and control devices have many cables, a small cable area, and are frequently constructed and modified. They are usually caused by irregular construction, no boundaries, misoperation, cable damage, and device damage, which lead to grounding, AC intrusion and other faults. The measurement and control devices use DC power supply, and insulation failures will cause accidents such as false operation and refusal of relay protection devices in the DC system, which is extremely harmful.

[0003] Until now, when insulation faults occur in telesignaling and measurement and control devices, only the DC system total insulation monitoring device can issue an alarm, and carry an insulation fault finder to find faults until the ground fault location is determined and the fault is handled. When insulation faults occur in the measurement and control device, due to the large number of outlet cables of the measurement and control device, it takes a long time to find and handle the insulation faults one by one, and the insulation faults cannot be eliminated in time, threatening the safe operation of the system.

[0004] In view of this, a remote signaling power supply device and method for automatically isolating insulation faults of a measurement and control device is needed. Summary of the invention

[0005] In view of the problem that when an insulation fault occurs in a measurement and control device in the prior art, it takes a long time to find and handle the insulation faults one by one due to the large number of outlet cables of the measurement and control device, and the insulation fault cannot be eliminated in time, threatening the safe operation of the system, the present invention provides a remote signaling power supply device and method for automatically isolating the insulation fault of the measurement and control device, which can ensure the power supply of the measurement and control device and isolate the insulation fault from the DC system at the same time, thereby ensuring the safe operation of the DC system. The specific technical scheme is as follows:

[0006] A remote signal power supply device for automatic isolation of insulation fault of a measurement and control device, characterized in that it comprises an MCU, an alarm module, a display module, an output insulation detection module, a control circuit, a DC contactor and a DC / DC isolation power supply;

[0007] The alarm module, display module, control circuit, output insulation detection module and DC / DC isolation power supply are respectively connected to the MCU for communication, the output insulation detection module and the DC contactor are also electrically connected to the control circuit, the output insulation detection module is used to measure and control the insulation fault of the device, and the DC contactor controls the on and off of the DC power supply;

[0008] The DC / DC isolated power supply also provides isolated power supply for the measurement and control device.

[0009] Preferably, the display module adopts DMG10600T070 touchable color screen.

[0010] Preferably, the control circuit includes a transistor and a relay, the base of the transistor is connected to the MCU, the emitter is connected to the relay, and the collector is grounded; the relay is connected to the DC contactor.

[0011] Preferably, the output insulation detection module includes a balanced bridge circuit and a voltage collection circuit, the balanced bridge circuit includes external balanced bridge resistors Rp1 and Rp2, and the voltage collection circuit includes a positive-to-ground voltage collection circuit and a negative-to-ground voltage collection circuit; one end of the positive-to-ground voltage collection circuit is connected to the positive electrode of the output terminal, and the other end is connected to the ground grid; one end of the negative-to-ground voltage collection circuit is connected to the negative electrode of the output terminal, and the other end is connected to the ground grid, one end of the resistor Rp1 is connected to the positive electrode of the output terminal, one end of Rp2 is connected to the negative electrode of the output terminal, the other end of the resistor Rp1, the switch K1, the switch K2, and the other end of the resistor Rp2 are connected in sequence; insulation resistors R+ and R- are connected between the positive electrode of the output terminal and the negative electrode of the output terminal.

[0012] A method for automatically isolating insulation faults of a measurement and control device is implemented by the remote signaling power supply device described above, and is characterized in that it comprises the following steps:

[0013] S1. When the measurement and control device is operating normally, the DC contactor is in a closed state, and the output insulation monitoring module detects the insulation state of the output end;

[0014] S2: When the output insulation monitoring module detects a ground fault or an AC inrush fault, the MCU controls the DC / DC isolation power supply to start outputting, and then controls the DC contactor to disconnect;

[0015] S3, the output insulation detection module continues to detect the insulation condition of the output end. If there is still an insulation fault, the control alarm module sends out an audible and visual alarm and a hard node signal;

[0016] S4, when the insulation fault at the output end is restored, after the insulation fault is restored, the MCU sends a command to the control circuit to control the DC contactor to close after a time T has passed;

[0017] S5. After the DC contactor is closed again, the DC / DC isolation power supply is controlled to stop output, and the measurement and control device resumes normal operation.

[0018] Preferably, in step S2, when the output end of the output insulation monitoring module detects a ground fault or an AC inrush fault, the specific detection method is as follows:

[0019] The output insulation detection module monitors the positive and negative ground voltages V+ and V- in real time;

[0020] The insulation resistance R+ and R- are calculated by the positive and negative voltages to ground V+ and V-.

[0021] Finally, calculate the AC inrush voltage Vac;

[0022] When any value of the insulation resistance R+, R- or Vac exceeds the alarm value, the MCU controls the DC / DC isolated power supply to start output and controls the DC contactor to disconnect through the control circuit.

[0023] Preferably, the alarm value can be set via a display module.

[0024] Preferably, in the above step S4, the time T can be set to a certain value, or can be set to allow only manual closing of the contactor.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. In the present invention, when the insulation is normal, the measurement and control device is powered by the DC system by closing the contactor, thereby ensuring the power supply reliability of the measurement and control device.

[0027] 2. In the present invention, when the insulation is abnormal, the DC contactor is disconnected and the DC / DC isolation power supply is started to power the measurement and control device, so that the insulation fault of the measurement and control device is isolated from the DC system, ensuring the safe operation of the DC system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0029] Figure 1 It is the system principle diagram of the present invention;

[0030] Figure 2 is a schematic diagram of a display module of the present invention;

[0031] Figure 3 is a control circuit diagram of the present invention;

[0032] Figure 4 This is a schematic diagram of the output insulation detection module of the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0035] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0036] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0037] Example:

[0038] See also Figure 1-4 , a remote signal power supply device for automatic isolation of insulation fault of a measurement and control device, comprising an MCU, an alarm module, a display module, an output insulation detection module, a control circuit, a DC contactor and a DC / DC isolation power supply;

[0039] The alarm module, display module, control circuit, output insulation detection module and DC / DC isolation power supply are respectively connected to the MCU for communication, the output insulation detection module and the DC contactor are also electrically connected to the control circuit, the output insulation detection module is used to measure and control the insulation fault of the device, and the DC contactor controls the on and off of the DC power supply;

[0040] The DC / DC isolated power supply also provides isolated power supply for the measurement and control device.

[0041] As a preferred embodiment, the display module adopts DMG10600T070 touchable color screen.

[0042] Specifically, the display module can input instructions to the MCU to implement real-time time setting, contactor recovery time setting, alarm parameter setting, mute and other commands, and can also receive MCU instructions to display system voltage, insulation status, historical records and other information

[0043] As a preferred embodiment, the control circuit is composed of a transistor and a relay, the base of the transistor is connected to the MCU, the emitter is connected to the relay, and the collector is grounded; the relay is connected to the DC contactor.

[0044] It can be understood that the control circuit is mainly composed of the s8550 transistor U1 and the relay J1. U1 receives the high-level command from the MCU to control the relay J1 to close, thereby controlling the DC contactor to close. U1 receives the low-level command from the MCU to control the relay J1 to open, thereby controlling the DC contactor to open.

[0045] As a preferred embodiment, the output insulation detection module includes a balanced bridge circuit and a voltage acquisition circuit, the balanced bridge circuit includes external balanced bridge resistors Rp1 and Rp2, and the voltage acquisition circuit includes a positive voltage acquisition circuit to ground and a negative voltage acquisition circuit to ground; one end of the positive voltage acquisition circuit to ground is connected to the positive electrode of the output terminal, and the other end is connected to the ground grid; one end of the negative voltage acquisition circuit to ground is connected to the negative electrode of the output terminal, and the other end is connected to the ground grid, one end of the resistor Rp1 is connected to the positive electrode of the output terminal, one end of Rp2 is connected to the negative electrode of the output terminal, the other end of the resistor Rp1, the switch K1, the switch K2, and the other end of the resistor Rp2 are connected in sequence; insulation resistors R+ and R- are connected between the positive electrode of the output terminal and the negative electrode of the output terminal.

[0046] It can be understood that when the DC contactor is closed, K1 and K2 are disconnected, and the balancing bridge is not put into the system to prevent the balancing bridge from affecting the system operation. When the DC contactor is disconnected, K1 and K2 are closed, and the balancing bridge is put into the output end, so that a voltage difference is generated between the positive and negative electrodes. The positive-to-ground voltage acquisition circuit and the negative-to-ground voltage acquisition circuit measure the positive-to-ground voltage V+ and the negative-to-ground voltage V- of the output end respectively, calculate the output insulation resistance through V+ and V-, and calculate the AC inrush voltage by calculating the V+ and V- ripple voltages.

[0047] In summary, the working principle of this embodiment is:

[0048] Step 1. When the measurement and control device operates normally, the DC contactor is in a closed state, and the output insulation monitoring module detects the insulation state of the output end; as shown in the figure, the input ends +KM and -KM ports of the measurement and control device are respectively connected to the positive and negative poles of the DC system bus; the output ends +CM and -CM ports are respectively connected to the positive and negative poles of the measurement and control device power supply.

[0049] Step 2: When the output insulation monitoring module detects a ground fault or an AC inrush fault, the MCU controls the DC / DC isolation power supply to start outputting, and then controls the DC contactor to disconnect; specifically:

[0050] The output insulation detection module monitors the positive and negative voltages to ground V+ and V- in real time. The insulation resistances R+ and R- are calculated by formulas (1) and (2) respectively, where Rp is the external balance bridge resistance, and the Rp resistance value is input and set through the display module. When there is an AC inrush voltage Vac in the system, the AC inrush voltage value is calculated by formula (3).

[0051]

[0052] When any value of the insulation resistance R+, R- or Vac exceeds the alarm value, the MCU controls the DC / DC isolation power supply to start output and controls the DC contactor to disconnect through the control circuit. The measurement and control device is powered by a DC / DC power supply, and the R+, R- or Vac alarm value can be set through the display module.

[0053] Step 3: The output insulation detection module continues to detect the insulation condition of the output end. If there is still an insulation fault, the control alarm module sends out an audible and visual alarm and a hard node signal; specifically:

[0054] After the DC contactor is disconnected, the switches K1 and K2 of the output insulation detection module are closed, and the positive and negative voltages to ground V+ and V- are monitored in real time. The insulation resistances R+ and R- are calculated respectively by formulas (4) and (5), and the AC inrush voltage value Vac is still calculated by formula (3).

[0055]

[0056] After the DC contactor is disconnected, if any of the measured R+, R- or Vac values ​​exceeds the alarm value, the MCU controls the alarm module to issue a light alarm and hard node model, and controls the display screen to display the alarm information.

[0057] Step 4, when the insulation fault at the output end is restored, after the insulation fault is restored, the MCU sends a command to the control circuit after a time T has passed, and controls the DC contactor to close; T can be set through the display module, or the DC contactor can be set to close manually.

[0058] S5. After the contactor is closed again, the DC / DC isolated power supply is controlled to stop output, and the measurement and control device resumes normal operation. Specifically, when the DC contactor is closed, K1 and K2 are disconnected, and the output insulation detection module monitors the positive and negative voltages to ground V+ and V- in real time; and calculates the insulation resistances R+ and R- respectively through formulas (1) and (2), and still calculates the AC inrush voltage value Vac through formula (3).

[0059] Those of ordinary skill in the art will appreciate that the units of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition of each example has been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0060] In the embodiments provided by the present invention, it should be understood that the division of units is only a logical function division, and there may be other division methods in actual implementation, for example, multiple units can be combined into one unit, one unit can be split into multiple units, or some features can be ignored, etc.

[0061] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0062] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-0nlyMemory), random access memory (RAM, RandomAccessMemory), mobile hard disk, magnetic disk or optical disk, etc., which can store program code.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A remote signaling power supply device with automatic isolation of insulation fault of a measurement and control device, characterized in that: Including MCU, alarm module, display module, output insulation detection module, control circuit, DC contactor and DC / DC isolated power supply; The alarm module, display module, control circuit, output insulation detection module and DC / DC isolation power supply are respectively connected to the MCU for communication, the output insulation detection module and the DC contactor are also electrically connected to the control circuit, the output insulation detection module is used to measure and control the insulation fault of the device, and the DC contactor controls the on and off of the DC power supply; The DC / DC isolated power supply also provides isolated power supply for the measurement and control device.

2. A remote signaling power supply device for automatic isolation of insulation fault of a measurement and control device according to claim 1, characterized in that: The display module adopts DMG10600T070 touch color screen.

3. A remote signaling power supply device for automatic isolation of insulation fault of a measurement and control device according to claim 1, characterized in that: The control circuit comprises a transistor and a relay, wherein the base of the transistor is connected to the MCU, the emitter is connected to the relay, and the collector is grounded; and the relay is connected to the DC contactor.

4. A remote signaling power supply device for automatic isolation of insulation fault of a measurement and control device according to claim 1, characterized in that: The output insulation detection module includes a balanced bridge circuit and a voltage collection circuit. The balanced bridge circuit includes external balanced bridge resistors Rp1 and Rp2. The voltage collection circuit includes a positive voltage collection circuit to ground and a negative voltage collection circuit to ground. One end of the positive voltage collection circuit to ground is connected to the positive electrode of the output terminal, and the other end is connected to the ground grid. One end of the negative voltage collection circuit to ground is connected to the negative electrode of the output terminal, and the other end is connected to the ground grid. One end of the resistor Rp1 is connected to the positive electrode of the output terminal, and one end of Rp2 is connected to the negative electrode of the output terminal. The other end of the resistor Rp1, the switch K1, the switch K2, and the other end of the resistor Rp2 are connected in sequence. Insulation resistors R+ and R- are connected between the positive electrode of the output terminal and the negative electrode of the output terminal.

5. A method for automatically isolating insulation faults in a measurement and control device, implemented by the remote signaling power supply device according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. When the measurement and control device is operating normally, the DC contactor is in a closed state, and the output insulation monitoring module detects the insulation state of the output end; S2: When the output insulation monitoring module detects a ground fault or an AC inrush fault, the MCU controls the DC / DC isolation power supply to start outputting, and then controls the DC contactor to disconnect; S3, the output insulation detection module continues to detect the insulation condition of the output end. If there is still an insulation fault, the control alarm module sends out an audible and visual alarm and a hard node signal; S4, when the insulation fault at the output end is restored, after the insulation fault is restored, the MCU sends a command to the control circuit to control the DC contactor to close after a time T has passed; S5. After the DC contactor is closed again, the DC / DC isolation power supply is controlled to stop output, and the measurement and control device resumes normal operation.

6. A method for automatically isolating insulation fault of a measurement and control device according to claim 5, characterized in that: In step S2, when the output end of the output insulation monitoring module detects a ground fault or an AC inrush fault, the specific detection method is as follows: The output insulation detection module monitors the positive and negative ground voltages V+ and V- in real time; The insulation resistance R+ and R- are calculated by the positive and negative voltages to ground V+ and V-. Finally, calculate the AC inrush voltage Vac; When any value of the insulation resistance R+, R- or Vac exceeds the alarm value, the MCU controls the DC / DC isolated power supply to start output and controls the DC contactor to disconnect through the control circuit.

7. The automatic isolation method for insulation fault of a measurement and control device according to claim 6 is characterized in that: The alarm value can be set via the display module.

8. The method for automatically isolating insulation fault of a measurement and control device according to claim 5, characterized in that: In the above step S4, the time T can be set to a certain value, or can be set to allow only manual closing of the contactor.

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