Portable negative control operation and maintenance detector

Abstract

The utility model relates to the field of electric power system, concretely relates to a portable negative control operation and maintenance detector, and negative control operation and maintenance detector includes signal source and TFT colour screen, the signal source includes three -phase voltage source and homophase current source, three -phase voltage source and homophase current source are connected with detection terminal electricity. The utility model after using this portable negative control operation and maintenance detector, solved the problem of single detection specification, and detection range is no longer limited to simple loop on-off and single point voltage / current data test, and even can detect whether the harmonic of industrial load generation and three -phase voltage are balanced, can also carry out equipment volume remarkable reduction, avoided the problem of equipment volume big, can high -efficiently complete the comprehensive check of negative control device integral function simultaneously, improved detection efficiency.

Description

Technical Field

[0001] This utility model relates to the field of power systems, specifically to a portable load control operation and maintenance testing instrument. Background Technology

[0002] Currently, during the construction of my country's power system, relevant personnel will uniformly install load control management terminals for all power users and power companies that have installed dedicated transformers, thereby improving the work efficiency of power workers and the management efficiency of the power system.

[0003] The load control management terminal not only needs to be verified before the power system is energized, but it is also prone to faults during actual operation, such as wiring errors leading to ineffective data collection, and excessive impedance due to long-term external environmental influences affecting power supply. These faults cause inconvenience to the management of the load control device, thus requiring regular maintenance and repair of the load control management terminal. In addition, after the load control management terminal is installed or replaced due to failure, the power supply company needs to establish and update the user's profile in the metering automation system to ensure that the power supply line, electricity code, meter parameters, load control management terminal parameters, etc., are consistent with the field work order records. However, there are problems such as errors and omissions in the field operation and maintenance work records and the inability to archive operation and maintenance data in a timely manner.

[0004] During operation and maintenance, multimeters are often used to test the phase parameters of field equipment. This method can only perform preliminary tests on circuit continuity and voltage and current data for single-point detection. The overall device is large in size and cannot efficiently verify the overall function of the load control device, resulting in low testing efficiency.

[0005] Therefore, it is necessary to invent a portable load control and maintenance testing instrument to solve the above problems. Utility Model Content

[0006] The purpose of this utility model is to provide a portable load control operation and maintenance tester. After using this portable load control operation and maintenance tester, the problem of limited testing specifications is solved. The testing range is no longer limited to simple circuit continuity and single-point voltage / current data testing. It can even detect harmonics generated by industrial loads and whether the three-phase voltage is balanced. It can also significantly reduce the size of the equipment, avoiding the problem of large equipment size. At the same time, it can efficiently complete the comprehensive verification of the overall function of the load control device, improving the testing efficiency.

[0007] To achieve the above objectives, this utility model provides the following technical solution: A load control maintenance testing instrument includes a signal source and a TFT color screen. The signal source includes a three-phase voltage source and a current source in phase, which are electrically connected to a testing terminal. The three-phase voltage source is configured to be installed at the distribution end before power is supplied, providing an adjustable three-phase voltage source. The current source in phase is configured to be installed at the distribution end before power is supplied, providing an adjustable current in phase. The testing terminal is used to read power information from the intelligent measurement terminal and each downstream branch load when power is off, and when power is on, the intelligent measurement terminal sends commands to the portable load control maintenance testing instrument. The amplitudes of the three-phase voltage source and the current in phase can be displayed on the TFT color screen.

[0008] Preferably, the positive and negative terminals of the in-phase current are connected in parallel with the input terminals of the three-phase voltage source, and the positive and negative terminals of the in-phase current and the three-phase voltage source are connected in series with the detection terminals of the circuit breaker, and the three-phase voltage source is connected in a star configuration.

[0009] Preferably, the RO pin of the detection terminal is connected to the TX pin of the MCU, the DI pin of the detection terminal is connected to the RX pin of the MCU, and the DE / RE pin of the detection terminal is connected to the GPIO pin of the MCU.

[0010] Preferably, the 0~3.3V voltage signal output by the three-phase voltage regulation circuit is connected through the ADC channel of the MCU, with each channel corresponding to one phase voltage.

[0011] Preferably, the GPIO pins of the MCU are connected to the signal lines of the pulse port via pull-up resistors or pull-down resistors.

[0012] Preferably, the rising or falling edge of the pulse signal is captured using the timer input capture function of the MCU.

[0013] Preferably, the detection terminal has a 485 interface.

[0014] Preferably, the TFT color screen is connected to the MCU's SPI1 via an SPI interface.

[0015] Preferably, the load control and maintenance testing instrument further includes a cycle port; the cycle port is connected to the MCU via a UART interface.

[0016] The technical effects and advantages provided by this utility model in the above technical solution are as follows: By adopting a Y-shaped star connection, the input terminals of the three-phase voltage source are connected in parallel with the positive and negative terminals of the same-phase current source, and the output terminal is connected to the circuit breaker detection terminal. The three-phase voltage source is configured to be installed at the distribution terminal before power is supplied, providing an adjustable three-phase voltage source. The same-phase current source is configured to be installed at the distribution terminal before power is supplied, providing an adjustable same-phase current. That is, the positive and negative terminals are connected in parallel with the input terminals of the three-phase voltage source, and the output terminal is connected to the circuit breaker detection terminal. Pre-power supply verification: When the power distribution system is not energized, an adjustable three-phase voltage source is provided to verify the correct wiring and basic functional integrity of the load control equipment, such as whether it can normally acquire voltage / current signals, thus improving detection efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a system topology diagram of Embodiment 1 of the present invention; Figure 2 This is a front view of Embodiment 1 of the present invention; Figure 3 This is a system topology diagram of Embodiment 2 of the present invention; Figure 4 This is a perspective view of Embodiment 2 of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. TFT color screen; 2. Positive current terminal; 3. Negative current terminal; 4. Three-phase voltage source input terminal; 5. Circuit breaker detection terminal; 6. Detection terminal; 7. Pulse port; 8. Cycle port; 9. Switch. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0021] Example 1: This utility model provides the following... Figure 1-2The portable load control operation and maintenance tester shown includes a signal source and a TFT color screen 1. The signal source includes a three-phase voltage source and a current source in phase, which are electrically connected to a test terminal 6; that is, a star connection (Y-type) is adopted, with the input terminal 4 of the three-phase voltage source connected in parallel to the positive and negative terminals of the current source in phase (the positive and negative terminals of the current source in phase include: current positive terminal 2 and current negative terminal 3), and the input terminal 4 of the three-phase voltage source connected to the circuit breaker test terminal 5 (corresponding to the three-phase voltage); wherein, the three-phase voltage source is configured with The system is designed to provide an adjustable three-phase voltage source, installed at the distribution terminal before power transmission. The in-phase current source is configured to provide an adjustable in-phase current, also installed at the distribution terminal before power transmission. Specifically, the positive and negative terminals of the in-phase current source are connected in parallel with the input terminal 4 of the three-phase voltage source. However, the input terminal 4 of the three-phase voltage source also needs to be set up separately (not connected to the in-phase current source). If connected in parallel with the in-phase current source, the output current of the current source may cause a voltage drop through the internal resistance of the voltage source, resulting in output voltage fluctuations (e.g., decreasing as the current increases), affecting the accuracy of the analog voltage. Setting up a separate input terminal 4 of the three-phase voltage source can eliminate the effect of this additional voltage drop, ensuring the stability of the three-phase voltage source output voltage (e.g., adjustable within the range of 0~380V with minimal fluctuation). The output terminal is connected to the circuit breaker detection terminal 5 (corresponding to the phase current).

[0022] Pre-power-on verification: When the power distribution system is not powered on, provide an adjustable three-phase voltage source (simulating the phase voltage of normal operation, such as 220V / 380V) and a current source of the same phase (simulating the load current) to verify the correctness of the wiring of the load control equipment (such as whether the three-phase voltage is balanced and whether the phase sequence is correct) and the integrity of basic functions (such as whether the voltage / current signal can be collected normally).

[0023] Fault Detection: During equipment operation, by adjusting the output of the voltage / current source (e.g., simulating voltage fluctuations, current overload), check whether the load control equipment can accurately collect data (e.g., whether the voltage value is within the allowable deviation range) and respond promptly to abnormalities (e.g., whether the overvoltage / undervoltage alarm function is normal). The positive and negative terminals of the same-phase current are connected in parallel with the input terminal 4 of the three-phase voltage source, and the positive and negative terminals of the same-phase current and the three-phase voltage source are connected in series with the circuit breaker detection terminal 5 respectively. The three-phase voltage source adopts a star connection.

[0024] The detection terminal 6 is used to read the power information of the intelligent measurement terminal and each branch load in the event of a power outage. In the event of a power outage, the intelligent measurement terminal sends instructions to a portable load control and maintenance detection instrument through the detection terminal 6. The positive and negative terminals of the same phase current source are connected in parallel with the input terminals of the three-phase voltage source to achieve power supply from the same power source (avoiding the phase difference problem caused by multiple power sources). The three-phase voltage source adopts a star connection (one end of the three phase voltages is connected together to form a neutral point, and the other end is connected to the circuit breaker detection terminal 5 respectively), and the output terminal corresponds to the three-phase voltage (phases A, B, and C).

[0025] The above solution overcomes the limitation of existing equipment that can only detect operating equipment, achieving full coverage of "pre-power-on verification" and "in-operation fault diagnosis" (i.e., detection is possible even without power). The three-phase voltage source input terminals are connected in parallel to the positive and negative terminals of the same-phase current source. This parallel connection reduces the number of power sources, lowers the size and weight of the equipment, enhances portability, reduces the workload of operators, and improves maintenance efficiency.

[0026] The amplitudes of the three-phase voltage source and the in-phase current can be displayed on the TFT color screen 1. The phase difference of the star-connected phase voltages is 120°, which conforms to the standard phase relationship of the power distribution system, ensuring the accuracy of the test results; The in-phase current source and the three-phase voltage source share the same power supply, which avoids phase drift between the voltage source and the current source, improves the reliability of the detection data, and thus improves the operation and maintenance efficiency.

[0027] Furthermore, the above solution improves detection accuracy and facilitates maintenance because phase-consistent voltage / current signals can more accurately reflect the acquisition performance of the load control equipment (such as voltage amplitude error and current phase deviation). In addition, the unified power supply method simplifies the circuit structure, reflects portability, reduces maintenance difficulty, and allows operators to start working without complicated training, thereby improving operation and maintenance efficiency.

[0028] The RO pin of detection terminal 6 is connected to the TX pin of the MCU, the DI pin of detection terminal 6 is connected to the RX pin of the MCU, and the DE / RE pin of detection terminal 6 is connected to the GPIO pin of the MCU. Specifically, the RO pin (Receive Output) of detection terminal 6 is connected to the TX pin (Transmit) of the MCU, and the DI pin (Data Input) of detection terminal 6 is connected to the RX pin (Receive) of the MCU.

[0029] Two-way data transmission: The connection between RO→TX and DI→RX of detection terminal 6 enables full-duplex communication between detection terminal 6 and MCU (detection terminal 6 can send the collected intelligent measurement terminal data to MCU through the RO pin, and MCU can issue commands to detection terminal 6 through the DI pin).

[0030] Command issuance and control: The DE / RE pin is connected to GPIO. The MCU can control the detection terminal 6 (such as turning the data acquisition function on / off) by controlling the level state (high / low) of this pin. Switch 9 can control whether the three-phase voltage source input terminal 4 of the MCU is powered on.

[0031] The above solution also has other positive technical effects, namely, achieving intelligent linkage: the MCU can automatically receive data collected by the detection terminal 6 (such as power information from the intelligent measurement terminal) without manual intervention, improving the efficiency of data acquisition; and supporting remote control: by sending commands from the MCU to the detection terminal 6, the working status of the load control management terminal can be remotely controlled (such as triggering tripping, reading parameters), improving the convenience of operation and maintenance; and strong compatibility: standard serial communication protocols (such as UART) enable the detection terminal 6 to be compatible with MCUs from different manufacturers, improving operation and maintenance efficiency and reducing equipment upgrade costs.

[0032] The 0~3.3V voltage signal output by the three-phase voltage regulator circuit is input through the MCU's ADC channel. Each channel corresponds to one phase voltage. The 0~3.3V voltage signal output by the three-phase voltage regulator circuit (corresponding to the amplitude of the three-phase voltage, e.g., 0V corresponds to the 0V phase voltage, 3.3V corresponds to the 380V phase voltage) is input through the MCU's ADC channel (Analog-to-Digital Converter). Each channel corresponds to one phase voltage (e.g., channel 1 corresponds to phase A, channel 2 to phase B, and channel 3 to phase C). The positive technical effect of this solution is improved voltage amplitude acquisition: the MCU converts the analog voltage signal (0~3.3V) output by the three-phase voltage regulator circuit into a digital signal (e.g., 0~4095, corresponding to a 12-bit ADC) through the ADC channel, obtaining the real-time amplitude of the three-phase voltage. The data is input through the MCU's 12-bit ADC channel (sampling frequency 1kHz), converting analog signals into digital signals of 0~4095. The data processing logic is as follows: the MCU converts the acquired digital signals into actual voltage values ​​and sends display commands to the TFT color screen via the SPI1 interface (communication rate 1MHz). The color screen displays the data as text 'Ua=220V'. Amplitude display and monitoring effect: The acquired digital signals are displayed on TFT color screen 1 (e.g., "Ua=220V", "Ub=218V", "Uc=222V"), ​​allowing maintenance personnel to intuitively understand the three-phase voltage status. TFT color screen 1 directly displays the voltage amplitude, eliminating the need for manual recording by maintenance personnel (e.g., using a notebook to record voltage values), reducing workload and improving detection efficiency. Anomaly detection effect: The MCU can compare the acquired voltage amplitude with a preset threshold (e.g., ±10% of the rated voltage) to determine if there are any abnormalities such as excessively high / low voltage (e.g., triggering an alarm when a phase voltage exceeds 300V).

[0033] Based on actual production needs, the GPIO pins of the MCU are connected to the signal lines of pulse port 7 via pull-up or pull-down resistors. This solution provides a signal shaping effect. The specific technical function of this design is that the pull-up resistor (or pull-down resistor) can stabilize the logic level of the pulse signal (e.g., 3.3V for high level and 0V for low level), and prevent the pulse signal from jittering due to external interference (e.g., electromagnetic noise) (e.g., misjudged as multiple pulses).

[0034] In many existing technologies, the pulse port 7 signal line is not connected to a resistor. If the pulse port 7 signal line is not connected to a resistor, it will be in a "floating" state (without a clear level), which is easily affected by external interference (such as static electricity) and will cause abnormal signal. The resistor connection in this application ensures the stability of the signal line.

[0035] The above solution can improve the accuracy of pulse acquisition. The specific technical effect is that the shaped pulse signal can more accurately reflect the pulse output of the intelligent measurement terminal (such as the pulse signal of the electricity meter), avoiding counting errors caused by signal jitter (such as over-counting / under-counting pulses).

[0036] By utilizing the MCU's timer input capture function, the rising or falling edge of a pulse signal is captured. The MCU's timer, in "input capture" mode, detects the moment of the pulse signal line's rising edge (signal transitioning from low to high) or falling edge (signal transitioning from high to low) (e.g., the start time of the pulse signal). This technical solution, through the periodic changes of the pulse signal, can promptly detect harmonic pollution in the power grid (such as harmonics generated by industrial loads), providing data support for harmonic mitigation. The input capture function captures the moment the pulse signal appears, ensuring the real-time performance of energy metering and harmonic analysis (e.g., updating energy data every second).

[0037] The detection terminal 6 uses a 485 interface, which is an industry-standard serial communication interface used for communication between the detection terminal 6 and smart measurement terminals (such as smart meters). The detection terminal 6 sends "reading instructions" (such as "read current power") to the smart measurement terminal through the 485 interface, and sends "control instructions" (such as "trigger trip") to the smart measurement terminal through the 485 interface to control the load control equipment. This solution also supports multi-device communication: the 485 interface supports bus-type communication (up to 32 devices can be connected), can simultaneously read data from multiple smart measurement terminals, and can remotely control the status of load control equipment (such as remote tripping and remote closing), improving the convenience of operation and maintenance.

[0038] The MCU's SPI1 interface is connected to the TFT color screen 1 via an SPI interface. Specifically, the MCU's SPI1 interface (Serial Peripheral Interface 1) is connected to the TFT color screen 1's SPI interface (e.g., the TFT color screen 1's SCK pin is connected to the MCU's SPI1_SCK, the MOSI pin to the MCU's SPI1_MOSI, and the CS pin to the MCU's SPI1_CS). This scheme serves a data transmission function: the MCU sends display data (such as voltage amplitude, pulse frequency, harmonic content, etc.) to the TFT color screen 1 through the SPI1 interface. The TFT color screen 1 can display the detection data in numerical or graphical formats (such as bar charts displaying phase voltages and line graphs displaying harmonic content), allowing maintenance personnel to easily understand the data (e.g., quickly identify which phase voltage is abnormal).

[0039] The MCU used in this application is HC32L130F8UA-QFN32 from Xiaohua Semiconductor.

[0040] Example 2: As Figure 3-4 As shown, the difference between this embodiment and Embodiment 1 is that the load control and maintenance tester also includes a cycle port 8. The UART interface (such as TXD, RXD) of the cycle port 8 is connected to the SPI / UART interface of the TFT color screen 1. The control power input terminal (such as +24V, GND) of the cycle port 8 is connected to the output terminal of the signal source through the terminal block. The core function of the cycle port 8 is to realize "load control by cycle". That is, when the power grid is abnormal (such as overvoltage or overload), the load is cut off or restored in sequence according to the preset cycle strategy to ensure the stable operation of the power grid. The cycle port 8 receives the cycle strategy (such as "first cycle priority trip", "second cycle next", "third cycle next") issued by the MCU. The cycle port 8 acts as the "execution terminal" of the MCU and executes the control action according to the strategy. The cycle port 8 communicates bidirectionally with the MCU via the UART interface (i.e., the cycle port 8 and the MCU are connected via the UART interface), transmitting "cycle control commands" (such as "cycle 1 trip") and "status feedback" (such as "cycle 1 trip successful"). The cycle port 8 receives the "cycle 1 priority trip" command issued by the MCU. When the power grid is abnormal (such as overvoltage), the first cycle load (such as part of the circuit in the residential area) is disconnected first. If the abnormality is not eliminated, the second and third cycle loads are disconnected in sequence. The cycle port 8 sends the "cycle 1 trip successful" status feedback to the MCU via the UART interface. The MCU displays the cycle execution result on the TFT color screen 1.

[0041] The connection steps are as follows: Physical connection: The UART_TXD (transmit) pin of round port 8 is connected to the USART0_RXD (receive) pin of the MCU, and the UART_RXD (receive) pin of round port 8 is connected to the USART0_TXD (transmit) pin of the MCU, forming an instruction transmission path of "round port 8 → MCU" and a status feedback path of "MCU → round port 8". At the same time, round port 8 feeds back the status information to the MCU, forming a closed-loop control of "instruction-execution-feedback", which ensures the accuracy and reliability of round control and improves detection efficiency.

[0042] The other design schemes in this embodiment are the same as those in Embodiment 1.

[0043] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A portable load control operation and maintenance testing instrument, comprising a signal source and a TFT color screen, characterized in that, The signal source includes a three-phase voltage source and a phase current source, which are electrically connected to the detection terminal. The three-phase voltage source is configured to be installed at the distribution end before power is supplied, providing an adjustable three-phase voltage source. The phase current source is configured to be installed at the distribution end before power is supplied, providing an adjustable phase current. The detection terminal is used to read the power information of the intelligent measurement terminal and each downstream branch load in the event of a power outage. In the event of a power outage, the intelligent measurement terminal sends commands to the portable load control and maintenance detection instrument through the detection terminal. The amplitudes of the three-phase voltage source and the phase current can be displayed on a TFT color screen.

2. The portable load control and maintenance testing instrument as described in claim 1, characterized in that, The positive and negative terminals of the in-phase current are connected in parallel with the input terminals of the three-phase voltage source, and the positive and negative terminals of the in-phase current and the three-phase voltage source are connected in series with the detection terminals of the circuit breaker. The three-phase voltage source is connected in a star configuration.

3. The portable load control and maintenance testing instrument as described in claim 2, characterized in that, The RO pin of the detection terminal is connected to the TX pin of the MCU, the DI pin of the detection terminal is connected to the RX pin of the MCU, and the DE / RE pin of the detection terminal is connected to the GPIO pin of the MCU.

4. The portable load control and maintenance testing instrument as described in claim 3, characterized in that, The 0~3.3V voltage signal output by the three-phase voltage regulation circuit is connected through the ADC channel of the MCU, with each channel corresponding to one phase voltage.

5. The portable load control and maintenance testing instrument as described in claim 4, characterized in that, Connect the GPIO pins of the MCU to the signal lines of the pulse port via pull-up or pull-down resistors.

6. The portable load control and maintenance testing instrument as described in claim 5, characterized in that, The rising or falling edge of the pulse signal is captured using the timer input capture function of the MCU.

7. The portable load control and maintenance testing instrument as described in claim 1, characterized in that, The detection terminal has a 485 interface.

8. The portable load control and maintenance testing instrument as described in claim 1, characterized in that, The TFT color screen is connected to the MCU's SPI1 via the SPI interface.

9. The portable load control and maintenance testing instrument as described in claim 1, characterized in that, The portable load control and maintenance testing instrument also includes a cycle port; the cycle port is connected to the MCU via a UART interface.

Images