Four-fusion integrated terminal and control method thereof

Abstract

The invention relates to the technical field of power control, in particular to a four-fusion integrated terminal and a control method thereof, and the terminal comprises a main control unit, and a metering module, a control module, a protection module and a terminal temperature measurement module which are electrically connected with the main control unit; the control method comprises the following steps: acquiring current data flowing through a terminal and temperature data of a terminal wiring terminal in real time; calculating a contact resistance estimation value; determining the maximum allowable safety current; real-time operation data are compared with the maximum allowable safety current, and when the real-time operation data exceed the maximum allowable safety current, a power adjusting instruction is generated; according to the invention, a flexible regulation and control strategy is executed, and the traditional rigid protection of'tripping once over-temperature 'is upgraded to flexible control of'active derating operation', so that the power utilization experience of a user is maintained to the greatest extent on the premise of ensuring that the wiring terminal is not subjected to thermal runaway.

Description

Technical Field

[0001] This invention relates to the field of power control technology, specifically to a four-in-one integrated terminal and its control method, and more particularly to a four-in-one integrated terminal and its control method for AC charging piles and distributed photovoltaic systems. Background Technology

[0002] With the rapid development of new energy technologies, AC charging piles for new energy vehicles have become an important part of power distribution. To effectively manage these devices, it is typically necessary to perform energy metering, operational status monitoring, communication interaction, and safety protection.

[0003] In existing technical solutions, the above functions are usually performed by distributed, independent devices. For example, a typical application scenario may require the simultaneous installation of smart meters (for metering), circuit breakers (for protection), data acquisition terminals or concentrators (for communication), and individual control switches. The use of multiple devices leads to problems such as complex installation, high cost, high failure rate, and inconvenient maintenance.

[0004] In terms of safety protection, the terminal blocks are key nodes for high-current transmission, and their contact reliability is directly related to the safe operation of the equipment. Due to thermal expansion and contraction, mechanical vibration, or oxidation and corrosion during long-term operation, the terminal blocks are prone to loosening, leading to increased contact resistance, which in turn can cause local overheating or even fire accidents.

[0005] Existing terminal temperature protection technologies have the following significant limitations:

[0006] Current protection methods mostly use fixed temperature thresholds, which only trigger actions when the temperature exceeds the set value, and cannot provide early warnings in the early stages of overheating.

[0007] Existing monitoring methods typically focus only on temperature itself, neglecting the influence of current on temperature. The system cannot distinguish whether the increase in terminal temperature is caused by "normal temperature rise due to excessive load current" or "abnormal heating due to poor terminal contact"; this can easily lead to misjudgment or failure under hidden faults with low current and high impedance.

[0008] When overheating is detected, the existing protection logic usually cuts off the circuit directly (trips the circuit breaker). This rigid control method can cause a sudden interruption of charging service, affecting the user's power experience. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention proposes a four-in-one integrated terminal and its control method, which integrates multiple functions and possesses precise contact status sensing and adaptive power adjustment capabilities.

[0010] This invention is achieved through the following technical solution:

[0011] A four-in-one integrated terminal includes: a main control unit and a metering module, a control module, a protection module, and a terminal temperature measurement module electrically connected to the main control unit;

[0012] The metering module is used to collect the current parameters flowing through the terminal in real time and send them to the main control unit;

[0013] The terminal temperature measurement module is installed at the terminal of the terminal and is used to detect the temperature data of the terminal in real time and send it to the main control unit.

[0014] The protection module is used to perform circuit disconnection operations according to the instructions of the main control unit or the preset protection logic;

[0015] The main control unit is used to receive the current parameters and the temperature data, and to calculate the contact characteristic parameters of the terminals;

[0016] The control module is used to adjust the load power according to the contact characteristic parameters.

[0017] Furthermore, it also includes a communication module electrically connected to the main control unit;

[0018] The communication module is used to establish a data interaction channel between the main control unit and external devices;

[0019] The control module includes a PWM pulse modulation unit and / or a power control unit;

[0020] The PWM pulse modulation unit is used to output a charging guidance signal with a variable duty cycle to the AC charging pile;

[0021] The power control unit is used to output active power adjustment commands to the photovoltaic inverter;

[0022] The main control unit is configured to select and enable the PWM pulse modulation unit or the power control unit based on the type of the access device.

[0023] A control method for a four-in-one integrated terminal, based on a four-in-one integrated terminal, the control method comprising:

[0024] Real-time acquisition of current data flowing through the terminal and temperature data of the terminal terminals;

[0025] Based on the current data and the temperature data, the estimated contact resistance, which characterizes the terminal contact performance, is calculated using thermoelectric coupling analysis logic.

[0026] Based on the estimated contact resistance value, determine the maximum permissible safe current under the current terminal condition;

[0027] The real-time operating data is compared with the maximum allowable safe current. When the real-time operating data exceeds the maximum allowable safe current, a power adjustment command is generated.

[0028] Alternatively, methods for acquiring current and temperature data include:

[0029] According to the preset sampling period The instantaneous current value output by the metering module is periodically and synchronously collected. The instantaneous terminal temperature value output by the terminal temperature measurement module ,in Indicates the current sampling time;

[0030] At the same time, obtain the reference temperature value of the current environment of the terminal. ;

[0031] The instantaneous current value, the instantaneous terminal temperature value, and the reference temperature value are stored in chronological order to construct a discretized time series.

[0032] Alternatively, methods for constructing discretized time series include:

[0033] Transient thermal equilibrium differential model of pre-installed terminals: ,in, For a moment The current, For a moment Terminal contact resistance, For a moment Terminal temperature, For a moment Ambient reference temperature, The equivalent heat capacity of the terminal. The equivalent thermal resistance of the terminal to the environment;

[0034] The transient thermal equilibrium differential model is transformed into the first... Discretized heat balance equations at sampling time: ,in, , , The first and second parts of the discretized time series are respectively the first and second parts of the discretized time series. The measured current, measured temperature, and ambient reference temperature at any given time.

[0035] Optionally, the methods for calculating the estimated contact resistance include:

[0036] Set length as A time sliding window is used to apply the discretized heat balance equation to the current time step. To the past The contact resistance is calculated by performing discrete integration over the time interval. : , ;

[0037] Based on the result of the cumulative summation operation, the estimated contact resistance value at the current moment is calculated in real time using the adaptive identification formula. : ;

[0038] in, This indicates a summation operation on the data within the sliding window. , , The first one in the sliding window Current data, terminal temperature, and ambient reference temperature data at each simulation point. For a small compensation constant, The equivalent heat capacity of the terminal. This refers to the thermal resistance of the terminal to the environment.

[0039] Optionally, the estimated contact resistance value calculated at the current moment can be used. and the current ambient reference temperature Calculate the maximum permissible safe current : ,in, The thermal resistance of the terminal to the environment. This refers to the maximum permissible operating temperature threshold for the terminal material.

[0040] Optionally, the current sample value flowing through the terminal is monitored in real time. When judged Greater than the maximum permissible safe current At that time, a power adjustment command is generated:

[0041] Identify the type of the currently accessing device and base it on the maximum permissible safe current. Calculate the target control quantity, send a power regulation signal that matches the device type to the access device, and limit the operating current of the access device.

[0042] As an optional embodiment, when the access device is identified as an AC charging pile, the step of sending a power adjustment signal includes:

[0043] Based on the maximum permissible safe current Calculate the target duty cycle of the charging guide signal The mapping relationship satisfies: ,in, This is the preset minimum sustaining current threshold.

[0044] Generate the final execution duty cycle ,in, For smoothing coefficients, The duty cycle of the previous execution time;

[0045] The PWM pulse modulation unit in the control module adjusts according to the target duty cycle. It adjusts the pulse waveform output to the charging pile's CP interface in real time to regulate the charging current of the charging pile.

[0046] As another optional embodiment, when the access device is identified as a distributed photovoltaic inverter, the step of sending a power regulation signal specifically includes:

[0047] Get the current grid voltage and power factor The maximum permissible safe current Converted to active power limit value : ;

[0048] The main control unit constructs a system that includes the active power limit value. The communication module sends the communication message to the control interface of the photovoltaic inverter, instructing the photovoltaic inverter to adjust its output power.

[0049] After a preset delay time following the issuance of the instruction Then, the real-time current flowing through the terminal is collected again. If it is determined that the real-time current has not yet decreased to the maximum permissible safe current; Next, the terminal is controlled to disconnect the grid connection circuit.

[0050] Compared with the prior art, the present invention has the following features and beneficial effects:

[0051] In terms of hardware architecture, this invention integrates a main control unit, a metering module, a control module, a protection module, and a terminal temperature measurement module within the same housing, enabling synchronous acquisition and integrated management of current parameters and terminal temperatures. In terms of control logic, it identifies the contact resistance of the terminal in real time, calculates the maximum allowable safe current under the current contact state, and generates power adjustment commands based on the contact resistance and the maximum allowable safe current.

[0052] This invention integrates metering, communication, control, protection, and terminal temperature measurement modules within a single housing, achieving a four-fold fusion of equipment functions. This solves the problems of complex on-site wiring, limited installation space, and high maintenance costs caused by the need for multiple devices to work together in existing technologies.

[0053] This invention uses a real-time contact resistance identification algorithm to quantify the contact resistance that characterizes the contact performance of terminals, thereby effectively distinguishing between normal temperature rise caused by excessive load and abnormal heating caused by loose or oxidized terminals, and achieving early warning.

[0054] This invention compares real-time operating data with the calculated maximum permissible safe current and implements a flexible control strategy, upgrading the traditional rigid protection of "tripping when over-temperature" to flexible control of "active derating operation". This ensures that the user's power experience is maintained to the maximum extent while ensuring that thermal runaway does not occur at the terminal. Attached Figure Description

[0055] The accompanying drawings illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the principles of the invention. These drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, but do not constitute a limitation on the embodiments of the present invention.

[0056] Figure 1 This is a structural schematic diagram of a four-in-one integrated terminal according to the present invention.

[0057] Figure 2 This is a technical roadmap of a four-in-one integrated terminal according to the present invention.

[0058] Figure 3 This is a flowchart illustrating a control method for a four-in-one integrated terminal according to the present invention. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0060] It should also be noted that, for ease of description, only the parts relevant to the present invention are shown in the accompanying drawings.

[0061] Where there is no conflict, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0062] Example 1

[0063] like Figure 1 and Figure 2 As shown, this embodiment provides a four-in-one integrated terminal, including: a main control unit and a metering module, a control module, a protection module, a terminal temperature measurement module and a communication module electrically connected to the main control unit.

[0064] The metering module is used to collect current parameters flowing through the terminal in real time and send them to the main control unit. The metering module has a built-in current transformer, which can measure operating parameters such as total and phase active power, reactive power, power factor, phase voltage, phase current, and frequency, as well as total and phase forward and reverse active power, with an accuracy of 0.5S class and reactive power level 2. It is used to measure electrical parameters such as voltage, current, and power, and to perform electrical energy metering.

[0065] The terminal temperature measurement module is installed at the terminal of the terminal and is used to detect the temperature data of the terminal in real time and send it to the main control unit; it is used to detect the temperature of the terminal with an error of ±1℃, and to report to the main control unit when the temperature exceeds the set limit (the temperature limit can be set locally and remotely);

[0066] The protection module is used to perform circuit disconnection operations according to the instructions of the main control unit or the preset protection logic; it includes an overvoltage protection unit, an undervoltage protection unit, a short circuit protection unit, an overload protection unit and a leakage current protection unit, which are used to cut off the circuit to protect the equipment and power grid safety when abnormal conditions such as overvoltage, undervoltage, short circuit, overload, and leakage current occur.

[0067] The communication module is used to establish a data interaction channel between the main control unit and external devices; it includes an RS-485 interface, a Bluetooth interface, an HPLC dual-mode communication module, and an RJ45 interface. The RS-485 interface is used for communication with local devices, supporting parameter setting and data reading; the Bluetooth interface is compatible with BLE 4.2 and above, used for on-site debugging and maintenance; the HPLC dual-mode communication module conforms to the State Grid Interconnection HPLC dual-mode communication standard, used for communication with the intelligent sensing terminal / TTU or concentrator in the distribution area; the RJ45 interface is used for communication with photovoltaic inverters, supporting data interaction with photovoltaic inverters from various manufacturers, thus realizing overall data interaction between the terminal and external devices.

[0068] The control module is used to adjust the load power according to the contact characteristic parameters;

[0069] The control module includes a PWM pulse modulation unit and / or a power control unit (supporting flexible adjustment methods such as numerical control, proportional control, and time-based control); the PWM pulse modulation unit is used to output a charging guidance signal with a variable duty cycle to the AC charging pile; the power control unit is used to output active power adjustment commands to the photovoltaic inverter.

[0070] The main control unit is used to receive the current parameters and the temperature data, and calculate the contact characteristic parameters of the terminals; the main control unit is configured to select and enable the PWM pulse modulation unit or the power control unit according to the type of the connected device.

[0071] In addition, the main control unit, metering module, control module, protection module, terminal temperature measurement module and communication module are all integrated into one housing. The housing is equipped with a manual / automatic switch and a status indicator. The manual / automatic switch is used to switch the terminal's working mode, and the status indicator is used to indicate the terminal's operating status (a flashing green light indicates normal operation, and a solid green light or a solid green light indicates abnormal operation).

[0072] The rated current of this terminal is 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A or 80A, and the number of poles is 2P or 4P; in terms of appearance, the dimensions are 103mm×65mm×63mm for 2P and 103mm×65mm×99mm for 4P.

[0073] Example 2

[0074] like Figure 3 As shown, a control method for a four-in-one integrated terminal is provided. First, the physical environment (current and temperature) is sensed in real time. Second, the contact resistance of the terminals is analyzed using an algorithm. Third, the maximum safe current of the system is calculated. Finally, a comparison is made to determine whether intervention in the device's operating power is necessary. The control method includes the following four key steps:

[0075] Step S1: Multi-dimensional data synchronous acquisition, real-time acquisition of current data flowing through the terminal and temperature data of the terminal wiring terminals.

[0076] The metering module collects current data flowing through the terminal in real time. Simultaneously, a terminal temperature measurement module located at the wiring point monitors the temperature data of the wiring terminals in real time. This temperature data is obtained from an onboard sensor on the main control board or from the initial ambient temperature during cold start of the equipment.

[0077] The acquired analog or digital signals are then synchronously sent to the main control unit.

[0078] Step S2: Dynamic identification of contact resistance. Based on the current data and the temperature data, the estimated contact resistance value characterizing the terminal contact performance is calculated using thermoelectric coupling analysis logic.

[0079] After receiving the above data, the main control unit performs edge computing using its built-in thermoelectric coupling analysis logic. Based on the principle of the thermal effect of current and the hysteresis response characteristics of temperature, it calculates an estimated contact resistance value that characterizes the tightness of the current physical connection of the terminals, reflecting whether there are hidden faults such as loosening or oxidation of the terminals.

[0080] Step S3: Establish safe operating boundaries. Based on the estimated contact resistance value, determine the maximum permissible safe current under the current terminal condition.

[0081] Based on the calculated contact resistance estimate and the current environmental conditions, the main control unit reverse-engineers the maximum current that the system can withstand before reaching thermal equilibrium, thereby determining the maximum permissible safe current under the current terminal conditions.

[0082] Step S4: Flexible power regulation. The real-time operating data is compared with the maximum allowable safe current. When the real-time operating data exceeds the maximum allowable safe current, a power regulation command is generated.

[0083] The main control unit compares the real-time operating data (actual current) reported by the metering module with the calculated maximum allowable safe current.

[0084] When the real-time operating data is determined to exceed the maximum allowable safe current, the main control unit generates a power adjustment command and schedules the corresponding hardware module to perform the adjustment according to the type of connected device:

[0085] Scenario A (AC charging pile): The PWM pulse modulation unit in the main control unit drives the control module to adjust the duty cycle of the guide signal output to the charging pile, thus physically limiting the charging current.

[0086] Scenario B (Distributed Photovoltaics): The main control unit sends active power adjustment commands to the photovoltaic inverter through the communication module (or the power control unit in the control module in conjunction with the communication interface) to limit its grid-connected power.

[0087] Example 3

[0088] This embodiment provides a detailed description of Embodiment 2.

[0089] Step S1: Multidimensional data synchronous acquisition.

[0090] S1.1, According to the preset sampling period (For example, every 100ms), periodically and synchronously acquire the instantaneous current value output by the metering module. The instantaneous terminal temperature value output by the terminal temperature measurement module ,in Indicates the current sampling time;

[0091] At the same time, obtain the reference temperature value of the current environment of the terminal. ;

[0092] The instantaneous current value, the instantaneous terminal temperature value, and the reference temperature value are stored in chronological order.

[0093] S1.2. Based on the law of conservation of energy, establish the transient thermal equilibrium differential equation for the terminal block. Expanding into a transient thermal equilibrium differential model of the terminal block: ,in, For a moment The current, For a moment Terminal contact resistance, For a moment Terminal temperature, For a moment Ambient reference temperature, The equivalent heat capacity of the terminal. This is the equivalent thermal resistance of the terminal to the environment.

[0094] S1.3 Since the main control unit processes digital signals, the above continuous differential equation needs to be transformed into a discrete-time difference equation using the backward difference method, and the differential terms need to be... Approximately: , obtained the Discretized heat balance equations at sampling time: ,in, , , The first and second parts of the discretized time series are respectively the first and second parts of the discretized time series. The measured current, measured temperature, and ambient reference temperature at any given time.

[0095] Step S2: Dynamic identification of contact resistance.

[0096] To eliminate the impact of instantaneous sensor noise (such as current fluctuations and temperature sampling jitter) on the calculation results, this embodiment does not directly use single-point data to calculate the resistance. Instead, it introduces an adaptive sliding window integration algorithm to perform energy accumulation calculation within a time window, thereby accurately identifying the contact resistance that is difficult to measure directly.

[0097] S2.1, Set the length as A time sliding window, for example, N=600, corresponding to 1 minute of data, is used. Within the window period, assuming the contact resistance is relatively stable (i.e., the rate of change is much smaller than the rate of change of current), the equations in S1.3 are applied within the window... Perform discrete integration within the inner space to calculate the contact resistance. : ,in, .

[0098] S2.2 Based on the result of the cumulative summation operation, the estimated contact resistance value at the current moment is calculated in real time using the adaptive identification formula. (Characterizing the degree of aging): ;

[0099] in, This indicates a summation operation on the data within the sliding window. , , The first one in the sliding window Current data, terminal temperature, and ambient reference temperature data at each simulation point. For a small compensation constant, The equivalent heat capacity of the terminal. This refers to the thermal resistance of the terminal to the environment.

[0100] Step S3: Establish safe operating boundaries.

[0101] Calculate Subsequently, instead of using a fixed temperature threshold, the safe operating boundary of the system is derived by working backward from the actual contact conditions.

[0102] Estimated contact resistance based on the current moment and the current ambient reference temperature Calculate the maximum permissible safe current : ,in, The thermal resistance of the terminal to the environment. This refers to the maximum permissible operating temperature threshold for the terminal material.

[0103] Step S4: Flexible power regulation.

[0104] S4.1, the main control unit will measure the current. With the calculated safe current When comparing, when determining Greater than the maximum permissible safe current At that time, a power adjustment command is generated:

[0105] like The system is maintaining normal operation.

[0106] like : Triggering a flexible reduction mechanism (instead of direct tripping).

[0107] S4.2 Identify the type of the currently accessed device and base it on the maximum permissible safe current. Calculate the target control quantity, send a power regulation signal that matches the device type to the access device, and limit the operating current of the access device.

[0108] S4.2.1 When the access device is identified as an AC charging pile, and At this time, the main control unit executes the following logic:

[0109] Based on the maximum permissible safe current Calculate the target duty cycle of the charging guide signal The mapping relationship established according to international standards satisfies: ,in, This is the preset minimum holding current threshold; here, 0.6 is a coefficient specified by the standard, meaning that 1% duty cycle corresponds to 0.6A of current.

[0110] In order to avoid Tiny fluctuations cause frequent jumps in the charging current. A first-order low-pass filter algorithm is introduced to generate the final duty cycle. : ,in, This is a smoothing coefficient (e.g., 0.1). The duty cycle of the previous execution time;

[0111] The PWM pulse modulation unit in the control module adjusts according to the target duty cycle. The pulse waveform output to the charging pile's CP interface is adjusted in real time to regulate the charging current of the charging pile. The duty cycle of the PWM pulse modulation unit output by the main control unit is... A 1kHz pulse signal is sent to the CP interface, forcing the on-board charger (OBC) to reduce its drawdown current. the following.

[0112] S4.2.2 When the access device is identified as a distributed photovoltaic inverter, and At this time, the main control unit executes the following logic:

[0113] Since photovoltaic inverters typically accept "active power percentage" or "absolute power value" commands, the main control unit needs to convert the current limit into a power limit and obtain the current grid voltage. and power factor The maximum permissible safe current Converted to active power limit value : ;

[0114] The main control unit constructs a system that includes the active power limit value. The communication message is sent to the control interface of the photovoltaic inverter through the communication module, instructing the photovoltaic inverter to adjust its output power; the main control unit constructs a write register instruction through the RJ45 interface (or HPLC module) based on the preset inverter communication protocol (such as Modbus RTU / TCP or SunSpec).

[0115] The decision logic is: if If the current power generation exceeds the calculated safety limit, an adjustment command is sent to update the inverter's "active power upper limit setting" register. .

[0116] After a preset delay time following the issuance of the instruction Then, the real-time current flowing through the terminal is collected again. If it is determined that the real-time current has not yet decreased to the maximum permissible safe current; Next, the terminal is controlled to disconnect the grid connection circuit.

[0117] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0118] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0119] Those skilled in the art should understand that the above embodiments are merely for illustrating the present invention and are not intended to limit the scope of the invention. Those skilled in the art can make other changes or modifications based on the above invention, and these changes or modifications still fall within the scope of the present invention.

Claims

1. A quad-meltable integrated terminal, characterized by, The utility model relates to a kind of four-fusion integrated terminal, comprising: Master unit and metering module, control module, protection module and terminal temperature measurement module electrically connected with the master unit; The metering module is used to collect current parameters flowing through the terminal in real time, and send it to the master unit; The terminal temperature measurement module is arranged at the terminal terminal, for real-time detection of terminal temperature data, and send it to the master unit; The protection module is used to perform circuit breaking operation according to the instruction of the master unit or the preset protection logic; The master unit is used to receive the current parameters and the temperature data, and calculate the contact characteristic parameters of the terminal; The control module is used to adjust the load power according to the contact characteristic parameters.

2. The quad-fusible integrated terminal of claim 1, wherein, It also includes a communication module electrically connected with the master unit; The communication module is used to establish a data interaction channel between the master unit and external equipment; The control module includes a PWM pulse modulation unit and / or a power control unit; The PWM pulse modulation unit is used to output a charging guide signal with variable duty cycle to the AC charging pile; The power control unit is used to output active power adjustment instructions to the photovoltaic inverter; The master unit is set to select to enable the PWM pulse modulation unit or the power control unit according to the type of access equipment.

3. A control method of a quad-homed integrated terminal, characterized by, Based on the four-fusion integrated terminal of claim 1 or 2, the control method comprises: Real-time acquisition of current data flowing through the terminal and temperature data of the terminal terminal; Based on the current data and the temperature data, the contact resistance estimation value representing the terminal contact performance is calculated by using thermocouple coupling analysis logic; According to the contact resistance estimation value, the maximum allowable safety current allowed under the current terminal state is determined; Compare real-time running data with the maximum allowable safety current, and generate power adjustment instructions when real-time running data exceeds the maximum allowable safety current.

4. The control method of a four-fusible one-body terminal according to claim 3, characterized by, The method for obtaining current data and temperature data comprises: according to a preset sampling period periodically synchronously collect the current instantaneous value output by the metering module and the terminal temperature instantaneous value output by the terminal temperature measurement module wherein denotes the current sampling moment; Simultaneously acquire a reference temperature value of an environment where the terminal is currently located ; The current instantaneous value, the terminal temperature instantaneous value and the reference temperature value are stored in time sequence to construct a discretized time sequence.

5. The control method of a four-fusible integrated terminal according to claim 4, wherein The method for constructing a discretized time sequence comprises: Transient thermal equilibrium differential model of pre-installed terminals: ,in, For a moment The current, For a moment Terminal contact resistance, For a moment Terminal temperature, For a moment Ambient reference temperature, The equivalent heat capacity of the terminal. The equivalent thermal resistance of the terminal to the environment; The transient heat balance differential model is converted into a first order difference equation using a backward difference method The discretized heat balance equation at the sampling instant: wherein, , , are the measured current, measured temperature and ambient reference temperature at the instant of the discretized time series, respectively.

6. The control method of a four-fusible integrated terminal according to claim 5, wherein The method for calculating the contact resistance estimation value comprises: A time sliding window of a set length is set, and the discretized heat balance equation is discretely integrated over the interval from the current time to the past time to calculate the contact resistance : , ; Based on the result of the cumulative summation operation, the adaptive identification formula is used to calculate the contact resistance estimation value in real time at the current time : ; wherein, denotes a summation operation over the data in the sliding window, , , are the current data, the terminal temperature and the ambient reference temperature data, respectively, at the nth inference time instant within the sliding window, is a small compensation constant, is the equivalent heat capacity of the terminal, is the thermal resistance of the terminal to the environment.

7. The control method of a four-fusible integrated terminal according to claim 3, wherein contact resistance estimate value calculated on the basis of the current time and the current ambient reference temperature , the maximum allowed safe current is calculated : wherein is the thermal resistance of the terminal pair to the environment, is the maximum operating temperature threshold allowed for the terminal material.

8. The control method of a quad-homed integrated terminal according to claim 7, wherein sampling values of the current flowing through the terminal when it is determined that the maximum allowable safe current a power adjustment instruction is generated identifying the type of the current access device and limiting the operating current of the access device based on the maximum allowed safe current calculating a target control quantity, sending a power adjustment signal matching the device type to the access device, and limiting the operating current of the access device.

9. The control method of a quad-homed integrated terminal according to claim 8, wherein, When it is identified that the access equipment is an AC charging pile, the step of sending power adjustment signal comprises: based on the maximum allowed safe current calculating a target duty cycle of the charging pilot signal , the mapping relationship satisfies: wherein, is a preset minimum maintenance current threshold generating a final execution duty cycle wherein, is a smoothing coefficient, is a previous execution duty cycle; The PWM pulse modulation unit in the control module adjusts the pulse waveform output to the charging pile CP interface according to the target duty ratio , and adjusts the charging current of the charging pile in real time.

10. The control method of a quad-homed integrated terminal according to claim 8, wherein When it is identified that the access equipment is a distributed photovoltaic inverter, the step of sending power adjustment signal specifically comprises: acquiring a grid voltage at a current time and a power factor converting the maximum allowed safety current into an active power limit value : ; The master control unit constructs a communication message containing the active power limit value and sends it to the control interface of the photovoltaic inverter through the communication module, instructing the photovoltaic inverter to adjust its output power. After a preset delay time Then, the real-time current flowing through the terminal is collected again If it is determined that the real-time current has not fallen to the maximum allowed safe current Then, the terminal is controlled to disconnect the grid-connected loop.

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