Measurement switch protection function misalignment analysis and switching protection method and measurement switch

Abstract

The invention discloses a measurement switch protection function misalignment analysis and switching protection method, which comprises the following steps of: establishing a current mapping relation between a measurement unit and a protection unit in a measurement switch, and a verification relation between the measurement unit and electric quantity data of an electric energy meter; the measurement unit and the protection unit carry out current data interaction and mutual verification, and whether a correct current relation is satisfied is judged according to a current mapping relation between the measurement unit and the protection unit; the measuring switch collects electric quantity data of the electric energy meter, and judges whether the electric quantity relation between the measuring unit and the electric energy meter is changed or not according to the verification relation between the measuring unit and the electric quantity data of the electric energy meter; the protection unit judges whether the sampling current is abnormal or not according to the verification result of the measurement unit. The invention further discloses a measuring switch. According to the invention, the technical problems of performing misalignment analysis and abnormity monitoring on the protection function of the measurement switch, reducing the risk of abnormal tripping and improving the reliability of the system are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of measuring switches, and in particular to a measuring switch protection function misalignment analysis and switching protection method and a measuring switch. Background Art

[0002] The measuring switch is a device widely used in the field of industrial automation. It is mainly used to measure, control and adjust physical quantities such as temperature, pressure, liquid level and flow. The design principle of the measuring switch is to control the switch state of the electrical signal according to the change of the measured physical quantity (such as temperature, pressure, flow, etc.). This device usually consists of two parts: the sensing element and the output element. The sensing element is used to sense the measured physical quantity and convert it into an electrical signal; the output element converts the electrical signal into mechanical motion or other forms of output signals. The measuring switch is used in the meter box and has the functions of high-precision electric energy metering, overload protection and short-circuit protection. Its metering function and protection function are independent functions. There are independent current sampling elements for current sampling, and overload and short-circuit protection are performed according to the current characteristics; the metering function has the characteristics of high current sampling accuracy, but the maximum value of the sampling current can only reach 1.5 times the rated current. The current sampling accuracy of the protection function is low, but it can sample a large current of 15 times the rated current. The patent document with application number 202123225171.9 discloses a waterproof intelligent measuring switch, including a measuring switch body and a waterproof cover, the measuring switch is connected to an electric wire, the waterproof cover is detachably connected to the electric wire on the measuring switch body, an air gap is provided between the waterproof cover and the measuring switch body, an exhaust channel is provided on the top of the waterproof cover, and an exhaust fan is provided at the bottom of the waterproof cover. At present, the metering and protection functions of the measuring switch are independently set, and the two types of current sampling and multi-party verification of electric energy meter data are not fully utilized to monitor the mutual protection function of the measuring switch. Therefore, it is urgent to propose a measuring switch protection function misalignment analysis and switching protection method and a measuring switch to solve the technical problem of how to perform misalignment analysis and abnormal monitoring of the protection function of the measuring switch, reduce the risk of abnormal tripping, and improve system reliability. Summary of the invention

[0003] The main purpose of the present invention is to propose a method for analyzing the misalignment of the protection function of a measuring switch and switching protection, and a measuring switch, aiming to solve the technical problem of how to perform misalignment analysis and abnormal monitoring of the protection function of the measuring switch, reduce the risk of abnormal tripping, and improve system reliability.

[0004] To achieve the above object, the present invention provides a method for measuring the misalignment analysis of a switch protection function and switching protection, wherein the method for measuring the misalignment analysis of a switch protection function and switching protection comprises the following steps:

[0005] S1. Establishing the current mapping relationship between the measuring unit and the protection unit in the measuring switch, and the verification relationship between the measuring unit and the electric quantity data of the electric energy meter;

[0006] S2, the measuring unit and the protection unit exchange current data and verify each other, and determine whether the correct current relationship is satisfied according to the current mapping relationship between the measuring unit and the protection unit;

[0007] If yes, the measuring unit continues to monitor the current of the protection unit; if no, step S3 is executed;

[0008] S3, the measuring switch collects the electric quantity data of the electric energy meter, and determines whether the electric quantity relationship between the measuring unit and the electric energy meter changes according to the verification relationship between the measuring unit and the electric quantity data of the electric energy meter;

[0009] If yes, the measurement unit is inaccurate and reports it; if no, execute step S4;

[0010] S4, the protection unit determines whether the sampled current is abnormal according to the verification result of the measurement unit;

[0011] If so, the current protection function is automatically turned off, and the protection function inaccuracy is actively reported, and the measurement unit performs overload protection.

[0012] In one of the preferred solutions, in the step S1, the measuring unit is used to collect and measure the electricity data of all the electric energy meters under the meter box, and perform inaccuracy analysis based on the electricity data.

[0013] In one of the preferred solutions, in step S2, the measuring unit exchanges current data with the protection unit via a serial port.

[0014] One of the preferred solutions, in step S3, the measuring unit collects the electricity data of the electric energy meter through RS485 communication.

[0015] In one of the preferred solutions, step S4 is specifically:

[0016] The protection unit determines whether its own sampling circuit is normal based on the verification result of the measuring unit. Specifically, the current of the measuring unit is used as a standard to determine whether the protection current of the protection unit is inaccurate. If so, the current protection function of the protection unit is turned off, and the fault status is reported to the measuring unit, which is actively reported to the main station system through the measuring unit. The measuring unit performs overload protection.

[0017] In one of the preferred solutions, the short-circuit protection function of the measuring switch is controlled by a backup protection module.

[0018] In one preferred solution, the step S4, before the measuring unit performs overload protection, further includes:

[0019] Determine whether the abnormal state of the protection unit has been eliminated;

[0020] If yes, return to step S2 and continue to monitor the current of the protection unit through the measuring unit;

[0021] If not, the measuring unit takes over the overload protection function, and the backup protection module takes over the short-circuit protection function.

[0022] A measuring switch including the measuring switch protection function misalignment analysis and switching protection method, the measuring switch including:

[0023] A measuring unit, a protection unit, a switch, a first three-phase mutual inductor and a second three-phase mutual inductor;

[0024] One end of the switch is respectively connected to the three-phase incoming terminals A, B, and C, and the other end of the switch is respectively connected to the measuring unit and the protection unit. The measuring unit is respectively connected to the first three-phase mutual inductor, the protection unit, and the electric energy meter. The protection unit is respectively connected to the second three-phase mutual inductor and the three-phase outgoing terminals A, B, and C, and the three-phase outgoing terminals A, B, and C are connected to the electric energy meter.

[0025] In one of the preferred solutions, the measuring switch is connected to a plurality of electric energy meters via an RS485 bus.

[0026] In the above technical solution of the present invention, the measuring switch protection function mismatch analysis and switching protection method includes the following steps: establishing a current mapping relationship between a measuring unit and a protection unit in the measuring switch, and a verification relationship between the measuring unit and the electric quantity data of the electric energy meter; the measuring unit and the protection unit exchange current data and verify each other, and judge whether the correct current relationship is satisfied according to the current mapping relationship between the measuring unit and the protection unit; if so, the measuring unit continues to monitor the current of the protection unit; if not, execute the next step; the measuring switch collects the electric quantity data of the electric energy meter, and judges whether the electric quantity relationship between the measuring unit and the electric energy meter changes according to the verification relationship between the measuring unit and the electric quantity data of the electric energy meter; if so, the measuring unit is mismeasured and reported; if not, execute the next step; the protection unit judges whether the sampled current is abnormal according to the verification result of the measuring unit; if so, the current protection function is automatically turned off, and the mismatch of the protection function is actively reported, and the measuring unit performs overload protection. The present invention achieves the purpose of misalignment analysis of the protection function through real-time monitoring of the protection unit by the measuring unit without increasing the hardware investment, realizes the double guarantee of the protection function, greatly increases the protection reliability of the measuring switch, and solves the technical problem of how to perform misalignment analysis and abnormal monitoring of the protection function of the measuring switch, reduce the risk of abnormal tripping, and improve system reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention 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 present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0028] Figure 1 A schematic diagram of a method for measuring switch protection function misalignment analysis and switching protection according to an embodiment of the present invention;

[0029] Figure 2 It is a schematic diagram of the structure of a measuring switch according to an embodiment of the present invention.

[0030] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with the implementation methods and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0031] 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 only 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.

[0032] It should be noted that all directional indications (such as up, down, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0034] Furthermore, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] See also Figure 1According to one aspect of the present invention, the present invention provides a method for measuring the misalignment analysis of a switch protection function and switching protection, wherein the method for measuring the misalignment analysis of a switch protection function and switching protection comprises the following steps:

[0036] S1. Establishing the current mapping relationship between the measuring unit and the protection unit in the measuring switch, and the verification relationship between the measuring unit and the electric quantity data of the electric energy meter;

[0037] S2, the measuring unit and the protection unit exchange current data and verify each other, and determine whether the correct current relationship is satisfied according to the current mapping relationship between the measuring unit and the protection unit;

[0038] If yes, the measuring unit continues to monitor the current of the protection unit; if no, step S3 is executed;

[0039] S3, the measuring switch collects the electric quantity data of the electric energy meter, and determines whether the electric quantity relationship between the measuring unit and the electric energy meter changes according to the verification relationship between the measuring unit and the electric quantity data of the electric energy meter;

[0040] If yes, the measurement unit is inaccurate and reports it; if no, execute step S4;

[0041] S4, the protection unit determines whether the sampled current is abnormal according to the verification result of the measurement unit;

[0042] If so, the current protection function is automatically turned off, and the protection function inaccuracy is actively reported, and the measurement unit performs overload protection.

[0043] Specifically, in the present embodiment, in the step S1, the measuring unit is used to collect and measure the electricity data of all the electric energy meters under the meter box, and perform inaccuracy analysis based on the electricity data; the measuring switch is calibrated in the factory for supply and demand, and a current magnitude mapping relationship is established between the measuring unit and the protection unit, and is stored in the parameter areas of the measuring unit and the protection unit. During the on-site operation, the measuring unit and the protection unit exchange current data through the serial port, perform mutual verification, and determine whether the correct current relationship is met.

[0044] Specifically, in this embodiment, the measuring switch serves as a total meter in the meter box. The measuring unit can measure the electric energy data of all users under the meter box. The measuring unit can also serve as a collector. Through RS485 communication, the electric energy data of all electric energy meters in the meter box are collected for inaccuracy analysis to determine whether the switch measurement is accurate.

[0045] Specifically, in this embodiment, the step S4 is specifically as follows: the protection unit determines whether its own sampling circuit is normal according to the verification result of the measuring unit; specifically, using the current of the measuring unit as a standard, determining whether the protection current of the protection unit is inaccurate; if so, turning off the current protection function of the protection unit, and reporting the fault status to the measuring unit, which is actively reported to the main station system through the measuring unit; the measuring unit performs overload protection.

[0046] Specifically, in this embodiment, the short-circuit protection function of the measuring switch is controlled by the backup protection module. At this time, there is no short-circuit short-delay protection function.

[0047] Specifically, in this embodiment, the step S4, before the measuring unit performs overload protection, further includes: determining whether the abnormal state of the protection unit is eliminated;

[0048] If yes, return to step S2 and continue to monitor the current of the protection unit through the measuring unit;

[0049] If not, the measuring unit takes over the overload protection function, and the backup protection module takes over the short-circuit protection function.

[0050] See also Figure 2 According to another aspect of the present invention, the present invention further provides a measuring switch, the measuring switch comprising:

[0051] A measuring unit, a protection unit, a switch, a first three-phase mutual inductor and a second three-phase mutual inductor;

[0052] One end of the switch is respectively connected to the three-phase incoming terminals A, B, and C, and the other end of the switch is respectively connected to the measuring unit and the protection unit. The measuring unit is respectively connected to the first three-phase mutual inductor, the protection unit, and the electric energy meter. The protection unit is respectively connected to the second three-phase mutual inductor and the three-phase outgoing terminals A, B, and C, and the three-phase outgoing terminals A, B, and C are connected to the electric energy meter.

[0053] Specifically, in this embodiment, the measuring switch is connected to a plurality of electric energy meters via an RS485 bus.

[0054] Specifically, in the present embodiment, the first three-phase mutual inductor is used for real-time acquisition of first current sampling data of the three-phase incoming lines A, B, and C, and transmits the first current sampling data to the measuring unit; the second three-phase mutual inductor is used for real-time acquisition of second current sampling data of the three-phase incoming lines A, B, and C, and transmits the second current sampling data to the protection unit; the measuring switch has two groups of current sampling, namely, a measuring unit and a protection unit, each of which has independent current sampling elements. The measuring unit and the protection unit communicate in real time through the serial port, and the measuring unit can read the real-time current sampling data of the protection unit, namely, the second current sampling data, and the protection unit drives the release to perform overload, short-circuit short-delay, and short-circuit instantaneous protection actions.

[0055] Specifically, in this embodiment, the switch includes switches for three phases A, B, and C, which are independently arranged at the incoming line ends of phase A, phase B, and phase C, respectively, for controlling the disconnection of the incoming lines.

[0056] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A method for measuring the inaccuracy of switch protection function analysis and switching protection, characterized in that: The following steps are involved: S1. Establishing the current mapping relationship between the measuring unit and the protection unit in the measuring switch, and the verification relationship between the measuring unit and the electric quantity data of the electric energy meter; S2, the measuring unit and the protection unit exchange current data and verify each other, and determine whether the correct current relationship is satisfied according to the current mapping relationship between the measuring unit and the protection unit; If yes, the measuring unit continues to monitor the current of the protection unit; if no, step S3 is executed; S3, the measuring switch collects the electric quantity data of the electric energy meter, and determines whether the electric quantity relationship between the measuring unit and the electric energy meter changes according to the verification relationship between the measuring unit and the electric quantity data of the electric energy meter; If yes, the measurement unit is inaccurate and reports it; if no, execute step S4; S4, the protection unit determines whether the sampled current is abnormal according to the verification result of the measurement unit; If so, the current protection function is automatically turned off, and the protection function inaccuracy is actively reported, and the measurement unit performs overload protection.

2. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to claim 1, characterized in that: In the step S1, the measuring unit is used to collect and measure the electric quantity data of all electric energy meters under the meter box, and perform inaccuracy analysis based on the electric quantity data.

3. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to any one of claims 1 to 2, characterized in that: In the step S2, the measuring unit exchanges current data with the protection unit via the serial port.

4. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to any one of claims 1 to 2, characterized in that: In the step S3, the measuring unit collects the electric quantity data of the electric energy meter through RS485 communication.

5. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to any one of claims 1 to 2, characterized in that: The step S4 is specifically: The protection unit determines whether its own sampling circuit is normal according to the verification result of the measuring unit; specifically, the current of the measuring unit is used as a standard to determine whether the protection current of the protection unit is inaccurate; if so, the current protection function of the protection unit is turned off, and the fault state is reported to the measuring unit, and actively reported to the main station system through the measuring unit; The measuring unit performs overload protection.

6. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to claim 5, characterized in that: The short circuit protection function of the measuring switch is controlled by the backup protection module.

7. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to any one of claims 1 to 2, characterized in that: The step S4, before the measuring unit performs overload protection, further includes: Determine whether the abnormal state of the protection unit has been eliminated; If yes, return to step S2 and continue to monitor the current of the protection unit through the measuring unit; If not, the measuring unit takes over the overload protection function, and the backup protection module takes over the short-circuit protection function.

8. A measuring switch comprising the measuring switch protection function misalignment analysis and switching protection method according to any one of claims 1 to 7, characterized in that: The measuring switch comprises: A measuring unit, a protection unit, a switch, a first three-phase mutual inductor and a second three-phase mutual inductor; One end of the switch is respectively connected to the three-phase incoming terminals A, B, and C, and the other end of the switch is respectively connected to the measuring unit and the protection unit. The measuring unit is respectively connected to the first three-phase mutual inductor, the protection unit, and the electric energy meter. The protection unit is respectively connected to the second three-phase mutual inductor and the three-phase outgoing terminals A, B, and C, and the three-phase outgoing terminals A, B, and C are connected to the electric energy meter.

9. The method for analyzing the misalignment of the protection function of a measuring switch and switching protection according to claim 8, characterized in that: The measuring switch is connected to a plurality of electric energy meters via an RS485 bus.

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