Method and system for calculating insulation state of balance bridge of insulation detection device

Abstract

The invention discloses an insulation state calculation method and system for a balance bridge of an insulation detection device, and relates to the technical field of insulation state calculation, and the method comprises the following steps: carrying out the troubleshooting of an insulation part of a DC system before the input of the insulation detection device; when the insulation detection device is put into use, a voltage measurement circuit for voltage detection is connected; and analyzing the original system insulation device through the collected voltage change state value to obtain the system insulation state. The method can adapt to the bridge resistance of the insulation device of the original direct current system, accurately calculate the insulation fault, automatically make up the defect when the bridge resistance of the insulation monitoring device of the original system has the defect, and improve the accuracy of insulation fault detection and the safety of the system. In addition, the device can be compatible with an original system insulation monitoring device, two devices can run in parallel, and the problem of insulation state monitoring of the newly-added direct-current screen cabinet is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of insulation state calculation, and in particular to a method and system for calculating the insulation state of a balance bridge of an insulation detection device. Background Art

[0002] In the power system, the monitoring of the insulation status of the DC system is crucial to ensure the safe and stable operation of the system. Existing insulation monitoring technologies mainly rely on the balanced bridge principle, the ping-pong bridge principle, and the balanced bridge and detection bridge principle to detect the insulation status of the DC system. However, these technologies have some limitations and shortcomings in practical applications, as follows:

[0003] When facing a DC system insulation fault, the existing insulation monitoring device may not be able to accurately judge and compensate for the defects of the bridge resistance, resulting in the inability to accurately test the insulation fault.

[0004] When there are defects in the bridge resistance of the insulation monitoring device of the original system, there is a lack of an automatic method to compensate for the defects in order to accurately test the insulation fault. Summary of the invention

[0005] In view of the problems existing in the insulation state calculation and system of the existing insulation detection device balance bridge, the present invention is proposed.

[0006] Therefore, the problem to be solved by the present invention is that the defects of the bridge resistance cannot be accurately determined and compensated, resulting in the inability to accurately test the insulation fault.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] In a first aspect, an embodiment of the present invention provides a method for calculating the insulation state of a balancing bridge of an insulation detection device, which comprises the following steps:

[0009] Before the insulation detection device is put into use, the insulation of the DC system should be checked;

[0010] When the insulation detection device is put into operation, the voltage measurement circuit for voltage detection is connected;

[0011] The original system insulation device is analyzed by collecting the voltage change status value to obtain the system insulation status.

[0012] As a preferred solution of the insulation state calculation method of the insulation detection device balance bridge of the present invention, the inspection steps before the insulation detection device is put into use include:

[0013] When the DC system insulation is in good condition, proceed to the next step;

[0014] When the insulation status of the DC system is in an abnormal state, it will prompt manual troubleshooting to eliminate the insulation fault.

[0015] As a preferred solution of the insulation state calculation method of the insulation detection device balance bridge of the present invention, the inspection steps when the insulation detection device is put into use include:

[0016] The voltage of the DC system to ground is collected through the voltage collection circuit, and the collected voltage result is used to judge whether the DC system is really in a good insulation state;

[0017] If the voltage still has deviation, it will prompt manual troubleshooting to eliminate the insulation fault;

[0018] When the voltage is in good condition, proceed to the next step.

[0019] As a preferred solution of the insulation state calculation method of the insulation detection device balance bridge of the present invention, the step of analyzing the insulation device of the original system includes:

[0020] A 50kΩ resistor was inserted between the negative electrode and the ground to simulate the insulation drop of the DC system, and the voltage change within 100s was monitored;

[0021] Record the voltage value of each changing state, and analyze the original system insulation device through the recorded voltage changing state value;

[0022] The analysis results include the balance bridge principle, the ping-pong bridge principle, and the balance bridge and detection bridge principle.

[0023] As a preferred solution of the insulation state calculation method of the insulation detection device balance bridge of the present invention, wherein: the judgment method of the balance bridge principle is that the voltage does not fluctuate;

[0024] When the balanced bridge principle is used, the steps for obtaining the system insulation state include:

[0025] Evaluate the resistance value of the balanced bridge and make a judgment;

[0026] When the bridge resistance is too large, compensate the balanced bridge;

[0027] When the bridge resistance is not too large, the balanced bridge is not compensated;

[0028] Adjust the detection bridge and test the system insulation based on the compensated balanced bridge and the adjusted detection bridge.

[0029] As a preferred solution of the insulation state calculation method of the insulation detection device balance bridge of the present invention, wherein: the judgment method of the ping-pong bridge principle is the existence of U+=0 phenomenon;

[0030] When the ping-pong bridge principle is used, the steps for obtaining the system insulation state include:

[0031] Evaluate the resistance value of the ping-pong bridge;

[0032] Compensated ping pong bridge;

[0033] The system insulation is tested based on compensated balance bridge and ping-pong bridge.

[0034] As a preferred solution of the insulation state calculation method of the insulation detection device balance bridge of the present invention, wherein: the discrimination method of the balance bridge and the detection bridge principle is that the voltage fluctuates and there is no U+=0 phenomenon;

[0035] When the balancing bridge and the detection bridge are used, the steps for obtaining the insulation state of the system include:

[0036] Evaluate the balancing bridge and the detection bridge;

[0037] The insulation of the balancing bridge and the detection bridge test system is based on the original device.

[0038] In a second aspect, an embodiment of the present invention provides an insulation state calculation system for a balancing bridge of an insulation detection device, which includes a power module circuit, a control CPU circuit, a display circuit, a voltage measurement circuit, a communication circuit, a bridge resistance compensation circuit, and an alarm circuit;

[0039] The power module circuit supplies power to the entire device;

[0040] The control CPU circuit completes data calculation, display processing, and communication processing;

[0041] The display circuit completes the human-computer interaction function;

[0042] The voltage measurement circuit completes the DC system voltage data acquisition function;

[0043] The communication circuit is a functional circuit for communicating with device components and a host computer;

[0044] The bridge resistance compensation circuit is designed with multiple resistors and a control input circuit, and the input resistor changes the system bridge resistance;

[0045] The alarm circuit outputs an alarm signal.

[0046] In a third aspect, an embodiment of the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the processor executes the computer program, it implements any step of the above-mentioned method for calculating the insulation state of the balancing bridge of the insulation detection device.

[0047] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, any step of the above-mentioned method for calculating the insulation state of the balancing bridge of the insulation detection device is implemented.

[0048] The beneficial effects of the present invention are: it can adapt to the bridge resistance of the original DC system insulation device, accurately calculate the insulation fault, and automatically make up for the defect when the bridge resistance of the insulation monitoring device of the original system has a defect, thereby improving the accuracy of insulation fault detection and the safety of the system. In addition, the present invention is also compatible with the insulation monitoring device of the original system, and two devices can be operated in parallel, effectively solving the problem of insulation status monitoring of the newly added DC panel cabinet. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0050] Figure 1 The present invention is a flow chart of a method for calculating the insulation state of a balancing bridge of an insulation detection device.

[0051] Figure 2 The structure diagram of the insulation state calculation system of the insulation detection device balance bridge.

[0052] Figure 3 The present invention is a schematic circuit diagram of a power module of an insulation state calculation system of a balancing bridge of an insulation detection device.

[0053] Figure 4 The schematic diagram of the control CPU circuit of the insulation state calculation system of the insulation detection device balance bridge.

[0054] Figure 5 The present invention is a schematic diagram of a voltage measurement circuit of an insulation state calculation system of a balancing bridge of an insulation detection device.

[0055] Figure 6 The present invention is a schematic diagram of a signal amplification circuit of an insulation state calculation system of a balancing bridge of an insulation detection device.

[0056] Figure 7 The present invention is a schematic diagram of a bridge resistance compensation circuit of an insulation state calculation system of a balancing bridge of an insulation detection device. DETAILED DESCRIPTION

[0057] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0058] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0059] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0060] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0061] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0062] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] Example 1

[0064] Reference Figure 1 , which is the first embodiment of the present invention, provides a method for calculating the insulation state of a balancing bridge of an insulation detection device, comprising the following steps:

[0065] S1. Before the insulation detection device is put into use, the insulation of the DC system should be checked.

[0066] The inspection steps before the insulation detection device is put into use include:

[0067] When the DC system insulation is in good condition, proceed to the next step;

[0068] When the insulation status of the DC system is in an abnormal state, it will prompt manual troubleshooting to eliminate the insulation fault.

[0069] S2. When the insulation detection device is put into operation, the voltage measurement circuit for voltage detection is connected.

[0070] The inspection steps when the insulation detection device is put into use include:

[0071] The voltage of the DC system to ground is collected through the voltage collection circuit, and the collected voltage result is used to judge whether the DC system is really in a good insulation state;

[0072] If the voltage still has deviation, it will prompt manual troubleshooting to eliminate the insulation fault;

[0073] When the voltage is in good condition, proceed to the next step.

[0074] S3. Analyze the original system insulation device through the collected voltage change state value to obtain the system insulation state.

[0075] The steps to analyze the original system insulation device include:

[0076] A 50kΩ resistor was inserted between the negative electrode and the ground to simulate the insulation drop of the DC system, and the voltage change within 100s was monitored;

[0077] Record the voltage value of each changing state, and analyze the original system insulation device through the recorded voltage changing state value;

[0078] The analysis results include the balance bridge principle, the ping-pong bridge principle, and the balance bridge and detection bridge principle.

[0079] The method of judging the principle of the balanced bridge is that the voltage does not fluctuate;

[0080] When the balanced bridge principle is used, the steps for obtaining the system insulation state include:

[0081] Evaluate the resistance value of the balanced bridge and make a judgment;

[0082] When the bridge resistance is too large, compensate the balanced bridge;

[0083] When the bridge resistance is not too large, the balanced bridge is not compensated;

[0084] Adjust the detection bridge and test the system insulation based on the compensated balanced bridge and the adjusted detection bridge.

[0085] The method for determining the ping-pong bridge principle is the existence of the U+=0 phenomenon;

[0086] When the ping-pong bridge principle is used, the steps for obtaining the system insulation state include:

[0087] Evaluate the resistance value of the ping-pong bridge;

[0088] Compensated ping pong bridge;

[0089] The system insulation is tested based on compensated balance bridge and ping-pong bridge.

[0090] The method of distinguishing the principle of the balancing bridge and the detection bridge is that the voltage fluctuates and there is no U+=0 phenomenon;

[0091] When the balancing bridge and the detection bridge are used, the steps for obtaining the insulation state of the system include:

[0092] Evaluate the balancing bridge and the detection bridge;

[0093] The insulation of the balancing bridge and the detection bridge test system is based on the original device.

[0094] This embodiment describes the specific operation steps of a method for calculating the insulation state of a balancing bridge of an insulation detection device, and how to monitor and analyze the insulation state of a DC system through this method;

[0095] Before putting the insulation detection device into use, first conduct a comprehensive inspection of the insulation status of the DC system. Use professional insulation testing equipment to check whether there are any obvious insulation faults or damage in the system;

[0096] After confirming that the DC system is in good insulation condition, connect the voltage measurement circuit. The circuit is designed for high impedance input to ensure that it does not affect the system balance bridge resistance. The voltage measurement circuit divides the voltage through 4 resistors with a total resistance of more than 1MΩ to achieve high input impedance without affecting the bridge resistance loop;

[0097] The voltage measurement circuit is used to collect the DC system voltage to ground. If the collected voltage is biased, the system will prompt manual intervention to troubleshoot and eliminate insulation faults.

[0098] If the voltage is in good condition, the system will simulate the insulation drop of the DC system. The specific operation is to insert a 50kΩ resistor between the negative pole and the ground, monitor the voltage change within 100 seconds, and record the voltage value of each change state;

[0099] Analyze the principle of the original system insulation device based on the recorded voltage change state value. If the analysis results show that there is a problem with the balance bridge principle, that is, the voltage does not fluctuate, the system will evaluate the balance bridge resistance value and make a judgment;

[0100] If the bridge resistance is too large, the system will compensate the balancing bridge and add a detection bridge to realize the balancing bridge + detection bridge technology to detect the insulation status;

[0101] If the bridge resistance is not too large, the system will not make compensation and will directly adjust the detection bridge. The system insulation will be tested based on the compensated balance bridge and the adjusted detection bridge.

[0102] After completing the above steps, the system will test the system insulation based on the original device balance bridge and detection bridge to obtain the system insulation status. If the system detects an insulation fault, it will output an alarm signal through the alarm circuit to prompt the operator to take appropriate measures.

[0103] In summary, the invention can adapt to the bridge resistance of the insulation device of the original DC system, accurately calculate the insulation fault, and automatically compensate for the defect when the bridge resistance of the insulation monitoring device of the original system has a defect, thereby improving the accuracy of insulation fault detection and the safety of the system. In addition, the invention can also be compatible with the insulation monitoring device of the original system, and two devices can be operated in parallel, effectively solving the problem of insulation status monitoring of the newly added DC panel cabinet.

[0104] Example 2

[0105] Reference Figure 2 to Figure 7 , based on the first embodiment, this embodiment further provides an insulation state calculation system for a balancing bridge of an insulation detection device, including a power module circuit, a control CPU circuit, a display circuit, a voltage measurement circuit, a communication circuit, a bridge resistance compensation circuit and an alarm circuit;

[0106] The power module circuit supplies power to the entire device;

[0107] like Figure 3 As shown, the power module circuit adopts a multi-channel output switching power supply design, outputs 12V and 5V, and designs the power chip ASM1117 to achieve a stable 3.3V output to ensure the reliable operation of the signal source.

[0108] The control CPU circuit completes data calculation, display processing, and communication processing;

[0109] like Figure 4 As shown, the control CPU circuit uses STM32F103ZET6, which is an ARM 32-bit Cortex TM --M3CPU, with the characteristics of fast running speed, large storage capacity, low power consumption and a large number of various functional interfaces.

[0110] The display circuit completes the human-computer interaction function;

[0111] Designed with 7-inch industrial touch screen.

[0112] The voltage measurement circuit completes the DC system voltage data acquisition function;

[0113] like Figure 5As shown in the figure, the voltage sampling circuit is designed with 4 resistors, and the total resistance of the resistors exceeds 1MΩ, which does not affect the bridge resistance loop of tens of kilo-ohms. After the input voltage is divided by the resistors, an optical coupler is designed to isolate and amplify the high voltage, and then differential amplification is performed through the operational amplifier, and finally data acquisition is performed. The circuit is as follows Figure 6 shown.

[0114] The communication circuit is a functional circuit for communicating with device components and a host computer;

[0115] The communication circuit uses a 485 communication level chip to design a 3-way serial port communication circuit to meet the communication needs of the device and related equipment.

[0116] The bridge resistance compensation circuit is designed with multiple resistors and a control input circuit, and the input resistor changes the system bridge resistance;

[0117] like Figure 7 As shown, a relay drive circuit is designed with a triode, and the power resistor is switched by controlling the on and off of the relay. The capacitor and diode of the relay are designed to eliminate the interference of the jitter to prevent the relay from erroneously switching the resistor to change the bridge resistance value of the system. Multiple similar resistor control circuits are designed between the positive and negative grounds to achieve the requirements of balanced bridge compensation and bridge input detection. The multiple power resistors include: 15kΩ, 20kΩ, 25kΩ, 30kΩ, 50kΩ, 100kΩ, 150kΩ, and 200kΩ.

[0118] The alarm circuit outputs an alarm signal;

[0119] The alarm circuit uses relays and transistors to complete the relay control and output circuit design, completing the alarm circuit design.

[0120] This embodiment also provides a computer device, which is suitable for the insulation state calculation method of the insulation detection device balance bridge, including a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement the insulation state calculation method of the insulation detection device balance bridge proposed in the above embodiment.

[0121] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0122] This embodiment further provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method for calculating the insulation state of the balancing bridge of the insulation detection device proposed in the above embodiment is implemented.

[0123] The storage medium proposed in this embodiment and the data storage method proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be found in the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0124] 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the present invention.

Claims

1. A method for calculating the insulation state of a balancing bridge of an insulation detection device, characterized in that: The following steps are included: Before the insulation detection device is put into use, the insulation of the DC system should be checked; When the insulation detection device is put into operation, the voltage measurement circuit for voltage detection is connected; The original system insulation device is analyzed by collecting the voltage change status value to obtain the system insulation status.

2. The method for calculating the insulation state of the insulation detection device balance bridge according to claim 1, characterized in that: The inspection steps before the insulation detection device is put into use include: When the DC system insulation is in good condition, proceed to the next step; When the insulation status of the DC system is in an abnormal state, it will prompt manual troubleshooting to eliminate the insulation fault.

3. The insulation state calculation method of the insulation detection device balance bridge according to claim 2, characterized in that: The inspection steps when the insulation detection device is put into use include: The voltage of the DC system to ground is collected through the voltage collection circuit, and the collected voltage result is used to judge whether the DC system is really in a good insulation state; If the voltage still has deviation, it will prompt manual troubleshooting to eliminate the insulation fault; When the voltage is in good condition, proceed to the next step.

4. The method for calculating the insulation state of the insulation detection device balance bridge according to claim 3, characterized in that: The steps to analyze the original system insulation device include: A 50kΩ resistor was inserted between the negative electrode and the ground to simulate the insulation drop of the DC system, and the voltage change within 100s was monitored; Record the voltage value of each changing state, and analyze the original system insulation device through the recorded voltage changing state value; The analysis results include the balance bridge principle, the ping-pong bridge principle, and the balance bridge and detection bridge principle.

5. The insulation state calculation method of the insulation detection device balance bridge according to claim 4, characterized in that: The method of judging the principle of the balanced bridge is that the voltage does not fluctuate; When the balanced bridge principle is used, the steps for obtaining the system insulation state include: Evaluate the resistance value of the balanced bridge and make a judgment; When the bridge resistance is too large, compensate the balanced bridge; When the bridge resistance is not too large, the balanced bridge is not compensated; Adjust the detection bridge and test the system insulation based on the compensated balanced bridge and the adjusted detection bridge.

6. The insulation state calculation method of the insulation detection device balance bridge according to claim 5, characterized in that: The method for determining the ping-pong bridge principle is the existence of the U+=0 phenomenon; When the ping-pong bridge principle is used, the steps for obtaining the system insulation state include: Evaluate the resistance value of the ping-pong bridge; Compensated ping pong bridge; The system insulation is tested based on compensated balance bridge and ping-pong bridge.

7. The method for calculating the insulation state of the balance bridge of the insulation detection device according to claim 6, characterized in that: The method of distinguishing the principle of the balancing bridge and the detection bridge is that the voltage fluctuates and there is no U+=0 phenomenon; When the balancing bridge and the detection bridge are used, the steps for obtaining the insulation state of the system include: Evaluate the balancing bridge and the detection bridge; The insulation of the balancing bridge and the detection bridge test system is based on the original device.

8. A system for calculating the insulation state of a balancing bridge of an insulation detection device, based on the method for calculating the insulation state of a balancing bridge of an insulation detection device according to any one of claims 1 to 7, characterized in that: It includes power module circuit, control CPU circuit, display circuit, voltage measurement circuit, communication circuit, bridge resistance compensation circuit and alarm circuit; The power module circuit supplies power to the entire device; The control CPU circuit completes data calculation, display processing, and communication processing; The display circuit completes the human-computer interaction function; The voltage measurement circuit completes the DC system voltage data acquisition function; The communication circuit is a functional circuit for communicating with device components and a host computer; The bridge resistance compensation circuit is designed with multiple resistors and a control input circuit, and the input resistor changes the system bridge resistance; The alarm circuit outputs an alarm signal.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for calculating the insulation state of the balancing bridge of the insulation detection device according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for calculating the insulation state of the balancing bridge of the insulation detection device according to any one of claims 1 to 7 are implemented.

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