Time current characteristic testing device for molded case circuit breaker based on multi-magnetic-circuit principle
The time-current characteristic test device for molded case circuit breakers based on the multi-magnetic circuit principle solves the problems of cumbersome recording and high cost caused by the independent circuit breaker testing system in the existing technology. It realizes high-precision circuit breaker performance testing and data analysis, thereby improving product performance and production efficiency.
Patent Information
- Application Number
- CN202423174947.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2026-01-06
- Estimated Expiration
- 2034-12-23
AI Technical Summary
In the existing technology, the tripping characteristic test of molded case circuit breakers requires three independent systems, which makes the recording of test results cumbersome and costly, and lacks a unified data acquisition and analysis method.
The time-current characteristic test device for molded case circuit breakers, which adopts the multi-magnetic circuit principle, includes an industrial PC, a data acquisition and control module, a multi-magnetic circuit high-current generator, and a switch operating power supply. By controlling multiple independent magnetic circuits to simulate different current and time conditions, and combining a high-precision measurement module and a data acquisition system, it can achieve accurate testing and data analysis of the circuit breaker.
It enables high-precision testing and reliability assessment of circuit breaker performance, generates detailed test reports, ensures stable performance of each batch of products, supports multiple test modes, and improves product design optimization.
Smart Images
Figure CN223770344U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of current source technology, specifically to a time current characteristic test device for a molded case circuit breaker based on a multi-magnetic circuit principle. Background Technology
[0002] Molded case circuit breakers (MCCBs) are important electrical protection devices widely used in low-voltage power distribution systems to protect circuits and equipment from overloads, short circuits, and other faults. To ensure reliable operation of MCCBs under various fault conditions, time-current characteristic tests are required to understand the tripping characteristics, a key performance indicator.
[0003] Currently, the tripping characteristic testing process for circuit breakers includes: testing the standard time delay characteristics, testing the time delay characteristics, and testing the instantaneous characteristics of miniature circuit breakers. Traditional testing equipment, considering size, transportation, and ease of design and production, designs separate systems for testing the standard time delay, time delay, and instantaneous characteristics of miniature circuit breakers. These three systems are independent and do not interfere with each other. The only difference between the three systems is the current value emitted by the constant current source. Furthermore, the test results need to be recorded manually, leading to cumbersome recording and high overall cost of the three systems. Utility Model Content
[0004] The purpose of this invention is to provide a time-current characteristic test device for molded case circuit breakers based on the multi-magnetic circuit principle, so as to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, this utility model provides the following technical solution:
[0006] A time-current characteristic testing device for a molded case circuit breaker based on a multi-magnetic circuit principle includes:
[0007] An industrial PC, used for control and time calculation;
[0008] The data acquisition and control module is connected to the industrial PC, the control loop, and the voltage acquisition and transmission module, and is used for current and time sampling.
[0009] The control circuit is connected to the voltage regulator and the multi-magnetic circuit high current generator respectively, and is used for current control and the opening and closing operation of the molded case circuit breaker under test.
[0010] The multi-magnetic-circuit high-current generator is connected to the voltage acquisition and transmission module and the molded case circuit breaker under test, respectively, and is used to generate test current for the molded case circuit breaker under test.
[0011] The switching power supply is connected to both the voltage acquisition and transmission module and the molded case circuit breaker under test, and is used to provide the opening and closing test power for the molded case circuit breaker under test.
[0012] Furthermore, the acquisition and control module is connected to the circuit between the multi-magnetic-circuit high-current generator and the molded case circuit breaker under test via a current transformer.
[0013] Furthermore, the acquisition control module is based on the NI acquisition controller, and the NI9205 high-speed acquisition module in the NI acquisition controller performs data acquisition.
[0014] Furthermore, the control loop includes a PLC and a PLC expansion module connected to the PLC, and the PLC expansion module is connected to the multi-magnetic circuit high-current generator for control.
[0015] Furthermore, the multi-magnetic-circuit high-current generator includes multi-magnetic-circuit transformers BK1-BK7. The test power supply is collected from the line voltages of A1 and C1, and supplied to the upper end of contactors KM11-KM22 through contactor KM1 and thyristor SSK in parallel.
[0016] Furthermore, multi-magnetic circuit transformers BK1-BK7 are respectively connected to the rear end of contactors KM11-KM21. Contactor KM15 is connected to multi-magnetic circuit transformers BK1-BK7 via voltage regulator BT1. Multi-magnetic circuit transformers BK1-BK7 are connected via connecting copper plate U1 to form the same magnetic circuit.
[0017] Furthermore, the external loop resistance withstand voltage tester and the break-in operation mechanism are connected to the PLC control via a PLC expansion module, and the break-in operation mechanism is connected to the break-in operation power supply.
[0018] Compared with the prior art, the beneficial effects of this utility model are:
[0019] This device tests circuit breakers under simulated current and time conditions to evaluate their performance and reliability. By controlling multiple independent magnetic circuits, precise current control is achieved, simulating various fault conditions and testing the circuit breaker's response. The control loop, consisting of a PLC and controller, is used to adjust the operating state of each magnetic circuit, set test parameters, and monitor the test process in real time. An NI data acquisition and control module is equipped for high-precision current and time measurements, used to monitor the circuit breaker's operating parameters in real time, ensuring data accuracy.
[0020] This device is used to acquire, store, and analyze test data in real time. Detailed test reports can be generated using an industrial PC to evaluate the time-current characteristics of the circuit breaker.
[0021] During the production process, this testing device is used to conduct time-current characteristic tests to ensure that the performance of each batch of circuit breakers is stable and meets design requirements. In the development of new circuit breaker models, the testing device is used to test their time-current characteristics, optimize design parameters, and improve product performance.
[0022] This device boasts high precision: employing a multi-magnetic circuit principle and a high-precision measurement module, it ensures the accuracy and reliability of test data. It is flexible: supporting multiple test modes and parameter settings, allowing for flexible adjustments to meet diverse testing needs. Its powerful data acquisition and processing system can analyze and store test data in real time, generating detailed test reports for subsequent analysis and improvement. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the overall architecture of this utility model.
[0024] Figure 2 This is the circuit diagram of the multi-magnetic-circuit high-current generator of this utility model.
[0025] Figure 3 This diagram shows the output capacity and voltage of each magnetic circuit in the multi-magnetic circuit transformer of this utility model.
[0026] Figure 4 This is a time-current characteristic diagram of the present invention under long delay, short delay, and instantaneous conditions.
[0027] Figure 5 This is a schematic diagram of the NI data acquisition controller of this utility model.
[0028] Figure 6 This is the start-up control circuit diagram of this utility model.
[0029] Figure 7 This is a schematic diagram of the power supply for this utility model.
[0030] Figure 8 This is a schematic diagram illustrating the operating principle of the device of this utility model.
[0031] Figure 9 This is the electrical schematic diagram of the voltage regulator control of this utility model.
[0032] Figure 10 This is the electrical schematic diagram of the PLC host of this utility model.
[0033] Figure 11 This is a schematic diagram of the contactor control principle of this utility model.
[0034] Figure 12 This is the electrical schematic diagram of the PLC expansion module of this utility model.
[0035] Figure 13 This is the electrical schematic diagram of the PLC expansion module 2 of this utility model.
[0036] Figure 14 This is a schematic diagram of the circuit resistance withstand voltage meter of this utility model.
[0037] Figure 15 This is a schematic diagram of the power supply for the break-in operation of this utility model.
[0038] Figure 16 This is a schematic diagram illustrating the break-in operation principle of this utility model. Detailed Implementation
[0039] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0040] In the description of this utility model, it should be noted that the terms "upper end," "lower end," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0041] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved with," "connected," etc., should be interpreted broadly. For example, "connection" 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; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0042] Please see Figures 1 to 16 This utility model provides a technical solution:
[0043] A time-current characteristic test device for molded case circuit breakers based on NI data acquisition using a multi-magnetic circuit principle includes an industrial PC, an NI acquisition and control module, a control loop, a voltage regulator, a multi-magnetic circuit high-current generator, a high-precision current transformer, a voltage acquisition and transmission module, and a switching power supply.
[0044] The following is a detailed introduction:
[0045] Industrial PC: Control and time calculation center; NI acquisition and control module: High-speed data acquisition system for current and time sampling. The NI acquisition and control module specifically uses the NI9174 synchronous acquisition host and the AI high-speed digital acquisition card NI9205 to form a sampling rate of up to 250kHz; Control loop: Composed of a PLC controller and its expansion modules, used for equipment current control and test sample opening and closing operations; Voltage regulator: The main control element for equipment current regulation. The voltage regulator is a Suzhou TSGC3-20kVA, with an input voltage of 380V and an output voltage of 0-400V; Multi-magnetic circuit high-current generator: A current source generating device that can efficiently generate current; High-precision current transformer: A 0.05-grade highly flexible coil with high response speed; Voltage acquisition and transmission module: Voltage acquisition and control. The voltage acquisition and transmission module is a GY33A low-delay transmitter with a rise time of less than 5µs;
[0046] Switching power supply: Voltage source for opening and closing the test sample. This device tests the circuit breaker and evaluates its performance and reliability by simulating different current and time conditions. Time-current characteristics are curves describing the operating time of the circuit breaker under different current conditions. These curves typically include long-delay, short-delay, and instantaneous operating characteristics. Long-delay characteristics are used for overload protection, while short-delay and instantaneous characteristics are used for short-circuit protection. The test device needs to simulate these conditions to evaluate the circuit breaker's performance. This device achieves precise current control by controlling multiple independent magnetic circuits, thereby simulating different fault conditions and testing the circuit breaker's response. The control system (i.e., the control loop, composed of a PLC and controller) is the core of the test device, used to adjust the operating state of each magnetic circuit, set test parameters, and monitor the test process in real time. It is equipped with a high-precision current and time measurement module (i.e., the NI acquisition and control module) to monitor the circuit breaker's operating parameters in real time, ensuring data accuracy.
[0047] This device is used to acquire, store, and analyze test data in real time. Through an industrial PC and a professional software platform (such as the IPATS2000 circuit breaker testing system), detailed test reports can be generated to evaluate the time-current characteristics of the circuit breaker. During the production process, this testing device is used to perform time-current characteristic tests to ensure the stable performance of each batch of circuit breakers and compliance with design requirements. In the development of new circuit breaker models, the testing device is used to test their time-current characteristics, optimize design parameters, and improve product performance. High precision: Utilizing a multi-magnetic circuit principle and a high-precision measurement module, the accuracy and reliability of test data are ensured. Flexibility: Supports multiple test modes and parameter settings, allowing for flexible adjustments based on different testing needs. Data analysis: A powerful data acquisition and processing system can analyze and store test data in real time, generating detailed test reports for subsequent analysis and improvement.
[0048] Figure 1The diagram shows the overall architecture of this device. Since different molded case circuit breakers require different test currents and different current-carrying times, the setting of test parameters and the entry of product information are completed by an industrial PC. Because the test current is related to the product characteristics, a controller is needed to adjust it to adapt to different test currents and current-carrying times. A multi-magnetic-circuit high-current generator replaces the traditional current booster, thus reducing the overall size.
[0049] The test time ranged from 0.1s to 10s, a relatively large span, such as... Figure 5 The data acquisition is performed using the NI9205 high-speed acquisition module from the NI acquisition controller. Figure 1 The output terminals AI0-AI1 of the medium transmitter are connected to this module; at the same time, an NI9421 high-speed digital acquisition card is configured to assist in judging the circuit status; after the test, the molded case circuit breaker is restored to the closed state by operating the power supply in preparation for the next test.
[0050] like Figure 2 As shown, the experimental circuit design is described as follows: The test power supply is acquired from the line voltages of A1 and C1; it is supplied to the upper end of contactors KM11-KM22 through contactor KM1 and thyristor SSK connected in parallel. Thyristor SSK is a zero-crossing thyristor, which can transfer current when the current crosses zero to prevent overcurrent. Contactor KM11 serves as an auxiliary current interruptor to prevent repeated current interruption by thyristor SSK, thus reducing its lifespan.
[0051] KM11-KM21 are each connected to a multi-magnetic circuit transformer BK1-BK7 at their rear ends. Contactor KM15 is connected to a multi-magnetic circuit transformer via voltage regulator BT1. These multi-magnetic circuit transformers are connected via connecting plate U1 to form a single magnetic circuit. During use, KM15 needs to be engaged every time to adjust the magnetic circuit; the other magnetic circuits are selectively engaged according to the different test currents. The molded case circuit breaker to be tested (i.e., the test specimen in Figure 1) is connected to... Figure 2 Tests were conducted at points A and B in the middle.
[0052] The output capacity and voltage between each magnetic circuit are as follows: Figure 3 As shown, the voltage and capacity configuration between magnetic circuits can be infinitely adjusted from 0 to 12000A according to the ratio, which greatly saves space and capacity compared with traditional voltage regulators and current boosters.
[0053] Table 1 lists the models and specifications of the main electrical components of this device.
[0054] Table 1
[0055] The following describes a complete test of a trip unit. Molded case circuit breakers require long-delay, short-delay, and instantaneous tests, typically with the current gradually increasing and the time gradually decreasing. Before the test, the test current values for the long-delay, short-delay, and instantaneous currents are set. At the start of the test, the program calculates the required magnetic circuit and voltage regulator voltage based on the set test current. The contactor corresponding to the magnetic circuit outputs first. The controller unit controls the voltage regulator to adjust until the voltage displayed on the voltage acquisition module matches the calculated voltage. The program then controls the thyristor SSK to output. The zero-crossing thyristor SSK will output voltage at the zero-crossing point within one cycle. The NI acquires the output current waveform synchronously through a high-precision current transformer. At this time, KM1 also outputs in parallel, reducing the operating current of thyristor SSK. Thyristor SSK disconnects, and the contactor bears the current. After 15 seconds, the contactor disconnects, and all contactors in the circuit disconnect. The waveform acquired by NI during the entire 15 seconds is uploaded to the program, which internally determines the duration of the current magnitude. This time is the long-delay setting trip time of the molded case circuit breaker. Immediately afterwards, because the molded case circuit breaker has tripped and is in the open state, the program controls the closing power supply to perform a closing operation to conduct a short-delay test. The short-delay test and instantaneous test are similar to the long-delay test in procedure, only differing in current and time, and will not be described further. After completing the tests sequentially, as shown... Figure 4 The time-current characteristic curves of the circuit breaker are obtained by graphically representing the time-current characteristics of long delay, short delay, and instantaneous time in logarithmic form.
[0056] like Figure 14-16 As shown, the loop resistance withstand voltage tester and the break-in operation mechanism are connected to the PLC control via a PLC expansion module. The loop resistance withstand voltage tester performs a conductive loop resistance test on the molded case circuit breaker under test, and the existing break-in operation mechanism automatically performs the break-in operation on the molded case circuit breaker. The break-in operation power supply provides operating power to the break-in operation mechanism.
[0057] The parts of this utility model not described are existing technologies.
[0058] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A multi-magnetic circuit principle molded case circuit breaker time current characteristic test device, characterized in that, It comprises: an industrial PC for control and time calculation; a collection control module connected with the industrial PC, a control circuit and a voltage collection and transmission module respectively, for current and time sampling; the control circuit is connected with a voltage regulator and a multi-magnetic circuit large current generator respectively, for current control and the on-off operation of the tested molded case circuit breaker; the multi-magnetic circuit large current generator is connected with the voltage collection and transmission module and the tested molded case circuit breaker respectively, for generating test current for the tested molded case circuit breaker; a switch operating power supply connected with the voltage collection and transmission module and the tested molded case circuit breaker respectively, for providing on-off test power supply for the tested molded case circuit breaker.
2. A time current characteristic testing device for a molded case circuit breaker of a multi-magnetic circuit principle as claimed in claim 1, characterized in that, The collection control module is connected to the circuit between the multi-magnetic circuit large current generator and the tested molded case circuit breaker through a mutual inductor.
3. A time current characteristic testing device for a molded case circuit breaker of a multi-magnetic circuit principle as claimed in claim 1, characterized in that, The collection control module is based on a NI collection controller, and the data collection is performed by a high-speed collection module NI9205 in the NI collection controller.
4. A time current characteristic testing device for a molded case circuit breaker of a multi-magnetic circuit principle as claimed in claim 1, characterized in that, The control circuit comprises a PLC and a PLC expansion module connected with the PLC, and the PLC expansion module is connected with the multi-magnetic circuit large current generator.
5. A time current characteristic testing device for a molded case circuit breaker of a multi-magnetic circuit principle as claimed in claim 4, characterized in that, The multi-magnetic circuit large current generator comprises multi-magnetic circuit transformers BK1-BK7, and the test power supply is collected from A1 and C1 line voltages, and is supplied to the upper ends of contactors KM11-KM22 through contactor KM1 and thyristor SSK in parallel.
6. A time current characteristic testing device for a molded case circuit breaker of multiple magnetic circuit principle as claimed in claim 5, characterized in that, The lower ends of contactors KM11-KM21 are respectively mounted with the multi-magnetic circuit transformers BK1-BK7, and the contactor KM15 is connected with the multi-magnetic circuit transformers BK1-BK7 through the voltage regulator BT1, and the multi-magnetic circuit transformers BK1-BK7 are connected through a connecting copper plate U1 to form a same magnetic circuit.
7. A time current characteristic testing device for a molded case circuit breaker of multiple magnetic circuit principle as claimed in claim 4, characterized in that, An external circuit resistance voltage resistance instrument and a running-in operation mechanism are connected with the PLC through the PLC expansion module and the PLC control.