Control operation state monitoring system for ac contactor of distribution box

Abstract

The utility model discloses a kind of for distribution box ac contactor control operating state monitoring system, it includes distribution box, zero-crossing voltage signal generating circuit, dial switch, single-chip microcontroller, relay and wireless communication module.The utility model is configured zero-crossing voltage signal generating circuit and dial switch, realized the comprehensive monitoring of distribution box input voltage, ac contactor control state, operating state, fault state and idle state, can accurately judge the fault state and idle state of ac contactor, and timely feedback to management platform, so that management personnel can master the operating state of distribution box in real time through management platform, reduce the frequency of on-site viewing, reduce management and operation cost, improve the intelligent level of distribution box, adapt to the trend of wisdom city construction and internet of things development, improve the operating reliability and management efficiency of distribution box.In addition overall structure is simple, with low cost, construction is simple, and has the advantages such as comprehensive function.

Description

Technical Field

[0001] This utility model relates to the field of distribution box technology, and specifically to a method for monitoring the operating status of AC contactor control in a distribution box. Background Technology

[0002] Municipal low-voltage power distribution is essential to everyone in the city. The stable operation of municipal distribution boxes and their circuits is a crucial link in the stable operation of the city. Before intelligent transformation, municipal distribution boxes achieved unmanned automatic control through time-controlled switches. Whether the automatic control was operating as set still required on-site inspection by maintenance personnel. Today, the Internet of Things has entered all areas of society, and the proposal of smart city construction is in line with this technological development trend. Traditional distribution boxes are also undergoing intelligent transformation.

[0003] Currently, the intelligent control component of a smart distribution box mainly consists of a management platform, a smart box controller, a wireless communication network, and AC contactors within the smart low-voltage distribution box. The smart box controller includes a wireless communication module, a microcontroller, and relay circuits. However, the monitoring of the operating status of the distribution box and its circuits presents two scenarios: one where there is no electrical parameter metering component, therefore no monitoring of the distribution box and its circuits' operating status; and another where there is an electrical parameter metering component, thus enabling monitoring of the distribution box and its circuits' operating status.

[0004] Without an electrical parameter metering system, managers cannot monitor the execution of instructions or the operation of the distribution box and its circuits in real time. This is essentially no different from a traditional distribution box controlled by a time-controlled switch, and it cannot reduce management and maintenance costs.

[0005] In cases where electrical parameter metering is configured, although the municipal power grid voltage can be monitored through the voltage transformer at the input end and the command status and the operation status of the distribution box and its circuits can be monitored through the current transformer at the output end, it is impossible to determine whether the current is zero or the current is due to an AC contactor failure or a circuit breakage when the current transformer detects zero current. Moreover, modifying the aforementioned situation with sampling technology will increase construction and material costs significantly, especially for projects where the number of AC contactors in the distribution box is inconsistent but the total number of AC contactors is large and only control is required without electrical parameter metering, which will add a lot of unnecessary costs. Utility Model Content

[0006] To address the aforementioned shortcomings, the purpose of this utility model is to provide a simple and easy-to-implement monitoring system for the control and operation status of AC contactors in distribution boxes.

[0007] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0008] A monitoring system for the control and operation status of AC contactors in a distribution box includes a distribution box, a zero-crossing voltage signal generation circuit, a DIP switch, a microcontroller, a relay, and a wireless communication module. The zero-crossing voltage signal generation circuit is configured with multiple channels, one of which monitors the input voltage of the distribution box, and the remaining channels correspond to the outputs of the respective AC contactors. The DIP switch is connected to the zero-crossing voltage signal generation circuit. The microcontroller is connected to the zero-crossing voltage signal generation circuit and is used to determine various states of the distribution box and AC contactors based on the input voltage level signal. The relay is used to execute commands from the microcontroller to control the closing and opening of each AC contactor. The wireless communication module is used to communicate with a management platform, receive instructions from the management platform and transmit them to the microcontroller for execution, and send the information fed back by the microcontroller after executing the instructions back to the management platform. The zero-crossing voltage signal generator circuit monitors the input voltage of the distribution box, determines whether the mains power grid is supplying power normally by the output level change, and sends a power failure signal to the platform when power fails. The microcontroller controls the relay to operate, determines whether the AC contactor is successfully closed or opened based on the level change of the zero-crossing voltage signal generator circuit, and sends corresponding information to the management platform. Based on the output level of the zero-crossing voltage signal generator circuit and the level state of the corresponding circuit, it determines whether the operation status of the AC contactor after closing or opening is normal. If an abnormal level change is detected during closing, opening, or operation and lasts for a period of time, it is determined that the AC contactor is faulty and a fault information is sent to the management platform. By pulling the input level of the zero-crossing voltage signal generator circuit of the corresponding circuit low through the DIP switch, the microcontroller detects the low level and determines that the AC contactor of that circuit is idle, and sends an idle information to the management platform.

[0009] As a preferred embodiment of the utility model, the distribution box has a three-phase input terminal, and the multi-channel AC contactor consists of eight AC contactors, all sharing the three-phase input, with each contactor outputting its own three-phase output. The zero-crossing voltage generation circuit is connected to any one of the three-phase input phases; the connection phase of the zero-crossing voltage generation circuit can be flexibly selected according to the specific wiring and usage requirements of the distribution box, improving the system's applicability. The distribution box is equipped with hooks, facilitating on-site installation and use. The DIP switch is located on the outer surface of the distribution box, allowing operators to easily adjust the switch without opening the distribution box or performing complex disassembly, thus improving the system's usability.

[0010] The beneficial effects of this utility model are as follows: By configuring a zero-crossing voltage signal generation circuit and a DIP switch, this utility model achieves comprehensive monitoring of the input voltage, AC contactor control status, operating status, fault status, and idle status of the distribution box. It can accurately determine the fault and idle status of the AC contactor and promptly feed this information back to the management platform. This allows management personnel to monitor the operating status of the distribution box in real time, reducing the frequency of on-site inspections, lowering management and maintenance costs, and improving the intelligence level of the distribution box. This aligns with the trends of smart city construction and the development of the Internet of Things, improving the operational reliability and management efficiency of the distribution box. Furthermore, the overall structure is simple, with advantages such as low cost, easy construction, and comprehensive functions, effectively reducing the management and maintenance costs of the distribution box. Attached Figure Description

[0011] Figure 1 This is a schematic diagram illustrating the principle of this utility model.

[0012] Figure 2 This is a schematic diagram of the microcontroller and its peripheral circuits in this utility model.

[0013] Figure 3 This is a schematic diagram of the zero-crossing voltage signal generation circuit in this utility model.

[0014] Figure 4 This is a schematic diagram of the distribution box in this utility model.

[0015] Figure 5 This is a flowchart illustrating the normal operation of the input voltage monitoring system for the distribution box of this utility model.

[0016] Figure 6 This is a flowchart of the power outage monitoring process for the input voltage of the distribution box according to this utility model.

[0017] Figure 7 This is a flowchart of the AC contactor control status monitoring of this utility model.

[0018] Figure 8 This is a flowchart of the AC contactor operation status monitoring of this utility model.

[0019] Figure 9 This is a flowchart of the AC contactor fault status monitoring method of this utility model.

[0020] Figure 10 This is a flowchart of the AC contactor's closing and opening fault status monitoring according to this utility model.

[0021] Figure 11 This is a flowchart of the fault status monitoring of the AC contactor during operation according to this utility model.

[0022] Figure 12 This is a flowchart of the AC contactor idle state monitoring method of this utility model. Detailed Implementation

[0023] Example: See Figures 1 to 12 This utility model provides a system for monitoring the operating status of an AC contactor control unit in a distribution box. The system includes a distribution box 1, a zero-crossing voltage signal generation circuit, a DIP switch 2, a microcontroller, a relay, and a wireless communication module. The microcontroller is preferably a GD32F303VET6 model.

[0024] The zero-crossing voltage signal generating circuit is used to configure multiple channels, one of which monitors the input voltage of the distribution box, and the remaining channels correspond to the outputs of various AC contactors. The DIP switch 2 is connected to the zero-crossing voltage signal generating circuit. The microcontroller is connected to the zero-crossing voltage signal generating circuit and is used to determine the various states of the distribution box and AC contactors based on the input level signal. The relay is used to execute microcontroller commands to control the closing and opening of each AC contactor. The wireless communication module is used to interact with the management platform, receive instructions from the management platform and transmit them to the microcontroller for execution, and send the information fed back by the microcontroller after executing the instructions back to the management platform. Preferably, the distribution box 1 is provided with a hook 3, which facilitates the on-site installation and use of the distribution box. The DIP switch 2 is located on the outer surface of the distribution box 1. This allows operators to easily operate the system without opening the distribution box or performing complex disassembly work to adjust the DIP switch, improving the system's usability.

[0025] See Figure 3 The zero-crossing voltage signal generating circuit includes a fuse, a rectifier diode, an optocoupler, a protection diode, a pull-up resistor, a current-limiting resistor, and a light-emitting diode. The fuse, rectifier diode, and current-limiting resistor are connected in series and connected to the anode of the optocoupler. The anode of the protection diode is connected to the cathode of the optocoupler, and the cathode of the protection diode is connected to the anode of the optocoupler. The pull-up resistor is connected to the collector of the optocoupler, and the light-emitting diode is connected in parallel to the collector and emitter of the optocoupler.

[0026] The following example uses a distribution box with three-phase input and eight AC contactors. All AC contactors share the three-phase input, and each contactor outputs its own three-phase output. Three states are defined for the zero-crossing voltage signal generation circuit: high level, high-low level, and low level. A high-level output indicates a fault; a high-low level output at 50Hz indicates a normal state; and a low-level output via a DIP switch indicates the contactor or circuit is idle. The DIP switch introduces a third state to the zero-crossing voltage signal generation circuit, solving the problem of relying solely on high and high-low levels for the signal, which prevents the identification of idle contactors when they are no longer in use. The circuit design and implementation achieves input / output status monitoring and fault monitoring of the distribution box by repeatedly using a single zero-crossing voltage signal generation circuit.

[0027] This system has nine zero-crossing voltage signal generation circuits. The ninth circuit is used for monitoring the shared input of the AC contactors and can be connected to any one of the three phases (L1, L2, L3). The first circuit connects to the predefined first AC contactor output in the distribution box. Generally, counting from left to right, the leftmost circuit is the first, and the rightmost is the eighth. Its wiring matches the input phase; for example, if the input is connected to phase L1, the output is connected to phase L1 of the branch. Circuits 2 through 8 follow the same pattern. Connecting the neutral wire to the neutral busbar completes the wiring. If one or more circuits from 1 to 8 of the AC contactor are not used, simply turn on the corresponding switch on the DIP switch.

[0028] Distribution box input voltage monitoring: A zero-crossing voltage signal generation circuit monitors the input voltage of the distribution box. Changes in the output level determine whether the mains power grid is supplying power normally, and a power failure signal is sent to the platform in the event of a power outage. For details, see [link to documentation]. Figure 5 The 9th zero-crossing voltage signal generation circuit is defined to monitor the input voltage of the distribution box. This circuit continuously outputs high and low levels to the microcontroller. If the microcontroller detects a continuous high and low level, it will determine that the mains power grid is energized and the input is normal.

[0029] When the mains power grid fails, see Figure 6 When there is no voltage input at the distribution box input terminal, the 9th zero-crossing signal generator circuit outputs a continuous high level to the microcontroller. The microcontroller detects this continuous high level for a certain period and determines that the mains power grid has failed, indicating no voltage input at the distribution box input terminal. The microcontroller immediately sends a mains power failure signal to the platform, thus achieving the purpose of mains voltage power supply fault status monitoring. All the following status monitoring functions are only valid when the distribution box input is normal, i.e., when the 9th zero-crossing voltage signal generator circuit provides the microcontroller with a continuous high or low level.

[0030] AC contactor control status monitoring: See Figure 7 The microcontroller controls the relay to operate, determining whether the AC contactor has successfully closed or opened based on the level change of the zero-crossing voltage signal generation circuit, and sends corresponding information to the management platform. Specifically, taking the control of the first AC contactor as an example: When the first AC contactor closes, the microcontroller sends a control signal, the relay executes the command, the contacts are activated, the AC contactor coil is powered, and the AC contactor closes. At this time, the first zero-crossing voltage signal generation circuit changes from a continuous high level to a continuous high-low level. The microcontroller detects the continuous high-low level and determines that the AC contactor has successfully closed. It then sends a message indicating that the first AC contactor has successfully closed to the management platform. The management platform receives this information and generates a log entry. When the circuit breaker is closed, the microcontroller sends a control signal, the relay executes the command, opens the contacts, de-energizes the coil of the first AC contactor, and the first AC contactor trips. At this time, the first zero-crossing voltage signal generator circuit changes from continuously outputting high and low levels to continuously outputting a high level. The microcontroller detects the continuously outputting high level, thus determining that the first AC contactor has successfully tripped, and then sends a message indicating that the first AC contactor has successfully tripped to the management platform. The management platform receives the information and generates a log entry. This completes the full control status monitoring from the management platform to the power supply circuit. The other AC contactors follow the same procedure.

[0031] AC contactor operation status monitoring: See Figure 8 Based on the output level of the zero-crossing voltage signal generating circuit and the level status of the corresponding circuit, determine whether the operating status of the AC contactor after closing or opening is normal.

[0032] Specifically, let's take the control of the first AC contactor as an example. After the first AC contactor closes normally, the first zero-crossing voltage signal generation circuit continuously outputs high and low levels. Simultaneously, the ninth zero-crossing voltage signal generation circuit continuously outputs high and low levels to the microcontroller, which determines that the AC contactor's closing operation is normal. Similarly, after the first AC contactor opens normally, the first zero-crossing voltage signal generation circuit continuously outputs a high level to the microcontroller, and the ninth zero-crossing voltage signal generation circuit continuously outputs high and low levels to the microcontroller, which determines that the first AC contactor's opening operation is normal. The same logic applies to the other AC contactors.

[0033] AC contactor fault status monitoring: See Figure 9 , Figure 10 and Figure 11 If an abnormal change in voltage level is detected and persists for a period of time during closing, opening, or operation, the AC contactor is judged to be faulty and a fault message is sent to the management platform; specifically, the control of the first AC contactor is used as an example.

[0034] ① AC contactor closing fault: The microcontroller detects that the 9th channel zero-crossing voltage signal generation circuit continuously outputs high and low levels. After determining that the power distribution box input is normal, it sends a closing signal. After that, the 1st channel zero-crossing voltage signal generation circuit should change from a continuous high level to a continuous high and low level. When the microcontroller does not detect the change in the output level of the 1st channel zero-crossing voltage signal generation circuit for a period of time, it determines that the 1st channel AC contactor cannot close. Subsequently, the microcontroller sends the 1st channel AC contactor closing fault information to the management platform.

[0035] ② AC contactor tripping fault: The microcontroller detects that the 9th channel zero-crossing voltage signal generator circuit continuously outputs high and low levels. After determining that the input of the distribution box is normal, it sends a tripping signal. After that, the 1st channel zero-crossing voltage signal generator circuit should change from continuous high and low levels to continuous high levels. When the microcontroller cannot detect the change in the output level of the 1st channel zero-crossing voltage signal generator circuit for a period of time, it determines that the 1st channel AC contactor cannot trip. Subsequently, the microcontroller sends the 1st channel AC contactor tripping fault information to the management platform.

[0036] ③ AC contactor malfunction during operation: When the first AC contactor is running normally after being closed, the microcontroller does not issue a trip command. However, the microcontroller detects that the zero-crossing voltage signal generation circuit of the ninth channel continuously outputs high and low levels, while the zero-crossing voltage signal generation circuit of the first channel changes from continuously outputting high and low levels to continuously outputting high levels. The microcontroller judges that the first AC contactor is faulty, and then sends the fault information of the first AC contactor to the management platform.

[0037] Similarly, when the first AC contactor is running normally after being tripped, the microcontroller does not issue a closing command. However, the microcontroller detects that the ninth zero-crossing voltage signal generator circuit continuously outputs high and low levels, while the first zero-crossing voltage signal generator circuit changes from continuously outputting a high level to continuously outputting a high and low level. The microcontroller determines that the first AC contactor is faulty and then sends the fault information of the first AC contactor to the management platform. The same logic applies to the other AC contactors.

[0038] AC contactor idle status monitoring: See Figure 12 The system uses a DIP switch to pull the input level of the zero-crossing voltage signal generator circuit for the corresponding circuit low. When the microcontroller detects this low level, it determines that the AC contactor on that circuit is idle and sends an idle status message to the management platform. Specifically, when one or more AC contactors in the distribution box are not in use, the corresponding switch of the DIP switch is turned on. The DIP switch pulls the signal voltage input to the microcontroller from the zero-crossing voltage signal generator circuit to 0. The microcontroller detects that the voltage level of the zero-crossing voltage signal generator circuit for that circuit is 0, determines that the AC contactor is not in use, and then sends a message to the management platform, thus achieving the purpose of monitoring the idle status of the AC contactors.

[0039] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments disclosed and described above, and some modifications and changes to this utility model should also fall within the protection scope of the claims of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model. Systems that are the same as or similar to those described in the above embodiments of this utility model are all within the protection scope of this utility model.

Claims

1. A system for monitoring the operating status of AC contactor control in a distribution box, comprising a distribution box, characterized in that, The distribution box has an input terminal and multiple AC contactor outputs; It also includes: Zero-crossing voltage signal generation circuit is used to configure multiple channels, one of which is used to monitor the voltage at the input terminal of the distribution box, and the other channels correspond to the output of each AC contactor. The DIP switch is connected to the zero-crossing voltage signal generation circuit. The microcontroller is connected to the zero-crossing voltage signal generation circuit and is used to determine the various states of the distribution box and AC contactor based on the input level signal. Relays are used to execute microcontroller commands and control the closing and opening of various AC contactors. The wireless communication module is used to interact and communicate with the management platform, receive instructions issued by the management platform and transmit them to the microcontroller for execution, and send the information fed back by the microcontroller after executing the instructions back to the management platform.

2. The system for monitoring the operating status of AC contactor control in a distribution box according to claim 1, characterized in that, The zero-crossing voltage signal generating circuit includes a fuse, a rectifier diode, an optocoupler, a protection diode, a pull-up resistor, a current-limiting resistor, and a light-emitting diode. The fuse, rectifier diode, and current-limiting resistor are connected in series and connected to the anode of the optocoupler. The anode of the protection diode is connected to the cathode of the optocoupler, and the cathode of the protection diode is connected to the anode of the optocoupler. The pull-up resistor is connected to the collector of the optocoupler, and the light-emitting diode is connected in parallel to the collector and emitter of the optocoupler.

3. The system for monitoring the operating status of AC contactor control in a distribution box according to claim 1, characterized in that, The distribution box has a three-phase input terminal, and the multi-channel AC contactor is an 8-channel AC contactor. All AC contactors share a three-phase input, and each AC contactor outputs its own three-phase output.

4. The system for monitoring the operating status of AC contactor control in a distribution box according to claim 1, characterized in that, The voltage zero-crossing generating circuit is connected to any one of the three-phase inputs.

5. The system for monitoring the operating status of AC contactor control in a distribution box according to claim 1, characterized in that, The distribution box is equipped with hooks.

6. The system for monitoring the operating status of AC contactor control in a distribution box according to claim 1, characterized in that, The DIP switch is located on the outer surface of the distribution box.

7. The monitoring system for the operating status of AC contactor control in a distribution box according to any one of claims 1-6, characterized in that, The microcontroller is model GD32F303VET6.

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