Power distribution protection system, method, power distribution equipment and power distribution system

Abstract

The present invention discloses a power distribution protection system, method, power distribution equipment and power distribution system, including a current transformer, a digital control terminal and a circuit breaker; wherein the input end of the circuit breaker is connected to the power distribution bus, the output end of the circuit breaker is connected to the power distribution circuit, a current transformer is also provided on the power distribution circuit side of the circuit breaker, the digital control terminal is respectively connected to the circuit breaker and the current transformer, and the circuit breaker has a circuit breaker operating component; the current transformer is used to collect the current signal of the power distribution circuit and transmit the current signal to the digital control terminal; the digital control terminal is used to generate a protection control signal according to the current signal collected by the current transformer, and send the protection control signal to the circuit breaker operating component; the circuit breaker operating component is used to perform closing or opening operations according to the protection control signal, so as to perform intelligent protection on the power distribution circuit. Thus, on the basis of using the physical properties of the circuit breaker itself to perform protection, dual protection is achieved for the power distribution system.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of electrical equipment, and in particular to a power distribution protection system, method, power distribution equipment, and power distribution system. Background Art

[0002] Low-voltage power distribution systems are usually used to reduce the transmission voltage of the power grid to distribution voltage through distribution transformers, and then supply low-voltage electricity to power-consuming equipment through low-voltage distribution equipment.

[0003] A low-voltage circuit breaker is installed at the power input end of the low-voltage power distribution system. The low-voltage circuit breaker is used to protect the power lines and motors, etc. It can automatically cut off the circuit when they have serious overloads or short circuits, undervoltage faults, etc. Its function is equivalent to the combination of a fuse switch and an overheating relay.

[0004] The above circuit protection utilizes the physical function of the low-voltage circuit breaker itself to perform circuit protection when a serious overload, short circuit, undervoltage or other fault occurs in the circuit. However, when the low-voltage circuit breaker fails, the power distribution system cannot be protected. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide a power distribution protection system, method, power distribution equipment and power distribution system to perform intelligent protection on the power distribution system.

[0006] A first aspect of an embodiment of the present invention provides a distribution protection system, comprising a current transformer, a digital control terminal and a circuit breaker; wherein the input end of the circuit breaker is connected to a distribution bus, the output end of the circuit breaker is connected to a distribution circuit, the current transformer is also provided on the distribution circuit side of the circuit breaker, the digital control terminal is respectively connected to the circuit breaker and the current transformer, and the circuit breaker has a circuit breaking operation component; the current transformer is used to collect a current signal of the distribution circuit and transmit the current signal to the digital control terminal; the digital control terminal is used to generate a protection control signal according to the current signal collected by the current transformer, and send the protection control signal to the circuit breaking operation component of the circuit breaker; the circuit breaking operation component is used to perform a closing or opening operation according to the protection control signal.

[0007] Optionally, the current transformer is arranged on the power distribution circuit.

[0008] Optionally, the circuit breaker operating component includes a shunt release or an electric operating mechanism.

[0009] Optionally, the electric operating mechanism includes a closing coil and an opening coil.

[0010] Optionally, the circuit breaker has multiple output terminals, and there are multiple current transformers, and the number of the current transformers is consistent with the number of the output terminals of the circuit breaker.

[0011] Optionally, the power distribution protection system is arranged in a power distribution system.

[0012] A second aspect of an embodiment of the present invention provides a power distribution device, comprising any one of the above-mentioned power distribution protection systems.

[0013] A third aspect of an embodiment of the present invention provides a power distribution system, comprising the above-mentioned power distribution equipment.

[0014] The fourth aspect of an embodiment of the present invention provides a distribution protection method, comprising: obtaining current data of a distribution circuit; judging whether the distribution circuit meets protection control conditions based on the current data; and when the conditions are met, sending a protection control signal to a circuit breaker to instruct a circuit breaker's circuit breaking operation component to perform a circuit breaking operation.

[0015] Optionally, the protection control condition includes: the power distribution circuit meets an overload protection condition and / or the power distribution circuit meets a short circuit protection condition.

[0016] Optionally, the acquiring current data of the power distribution circuit further includes: sampling the current data to acquire a sampled current value.

[0017] Optionally, judging whether the distribution circuit meets the protection control conditions according to the current data includes: determining the average current value of the current in each cycle according to the sampled current value; if the average current value of any first cycle is greater than a first current threshold, then accumulating and counting the heat values ​​generated by the current in multiple consecutive cycles starting from the first cycle, and the average current value of the multiple consecutive cycles is not less than a second current threshold; when the accumulated heat value exceeds the set heat threshold, it is determined that the distribution circuit meets the overload protection conditions.

[0018] Optionally, judging whether the distribution circuit meets the protection control conditions according to the current data also includes: determining the change slope value of the sampled current value based on the sampled current value, and if it is determined that the change slope value of the first number of consecutive sampled current values ​​exceeds a set slope threshold, then it is determined that the distribution circuit meets the short-circuit protection conditions.

[0019] Optionally, judging whether the distribution circuit meets the protection control condition based on the current data also includes: determining the instantaneous current value based on the sampled current value, and if the second consecutive number of instantaneous current values ​​exceeds a third current threshold, determining that the distribution circuit meets the short-circuit protection condition.

[0020] The power distribution protection system, method, power distribution equipment and power distribution system provided in this embodiment are provided with a current transformer and a digital control terminal connected to the current transformer and the circuit breaker, and the digital control terminal analyzes the current data collected by the current transformer to generate a protection control signal to control the circuit breaker's circuit breaker to perform a circuit breaker operation of closing or opening, thereby performing intelligent protection on the power distribution circuit. Thus, on the basis of performing protection by utilizing the physical properties of the circuit breaker itself, dual protection is achieved for the power distribution system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a structural block diagram of a power distribution protection system provided by Embodiment 1 of the present invention;

[0022] Figure 2 is a flow chart of the steps of a power distribution protection method provided by Embodiment 2 of the present invention;

[0023] Figure 3 This is a step flow chart of a power distribution protection method provided in Embodiment 3 of the present invention. DETAILED DESCRIPTION

[0024] The specific implementation of the embodiment of the present invention is further described in detail below in conjunction with the accompanying drawings (the same reference numerals in several drawings represent the same elements) and embodiments. The following embodiments are used to illustrate the embodiments of the present invention, but are not used to limit the scope of the embodiments of the present invention.

[0025] Those skilled in the art can understand that the terms "first" and "second" in the embodiments of the present invention are only used to distinguish different steps, devices or modules, etc., and neither represent any specific technical meaning nor indicate the necessary logical order between them.

[0026] Embodiment 1

[0027] Reference Figure 1 , shows a structural block diagram of a power distribution protection system provided in Embodiment 1 of the present invention.

[0028] Reference Figure 1 The power distribution protection system provided in the first embodiment of the present invention includes a current transformer 1, a digital control terminal 2 and a circuit breaker 3.

[0029] The input end of the circuit breaker 3 is connected to the distribution bus 4 of the low-voltage power distribution system, and the output end of the circuit breaker 3 is connected to the distribution circuit 5. The current transformer 1 is also provided on the distribution circuit side of the circuit breaker 3, and the digital control terminal 2 is respectively connected to the circuit breaker 3 and the current transformer 1, and the circuit breaker 3 has a circuit breaker operation component.

[0030] That is, the circuit breaker 3 is arranged between the distribution bus 4 and the distribution circuit 5, and the electrical equipment is connected to the distribution circuit 5 so as to obtain power through the distribution circuit 5. When the distribution system encounters a serious overload, short circuit or other fault, the circuit breaker 3 can perform a circuit breaking operation through its own thermal magnetic protection performance, thereby effectively protecting the distribution system.

[0031] The current transformer 1 of this embodiment may be arranged on the power distribution circuit 5 .

[0032] On this basis, the current transformer 1 is used to collect the current signal of the distribution circuit 5 and transmit the current signal to the digital control terminal 2; the digital control terminal 2 is used to generate a protection control signal according to the current signal collected by the current transformer 1, and send the protection control signal to the circuit breaker 3; the circuit breaker operation component is used to perform closing or opening operations according to the protection control signal.

[0033] The power distribution protection system provided in this embodiment is provided with a current transformer and a digital control terminal connected to the current transformer and the circuit breaker. The digital control terminal analyzes the current data collected by the current transformer to generate a protection control signal to control the circuit breaker's circuit breaker to perform a circuit breaker operation of closing or opening, thereby performing intelligent protection on the power distribution circuit. Thus, dual protection is achieved for the power distribution system on the basis of using the physical properties of the circuit breaker itself to perform protection.

[0034] Specifically, the current transformer 1 in this embodiment can be, but is not limited to: a shunt, an electromagnetic current transformer, an electronic current transformer, etc.

[0035] Specifically, a program for judging protection control is stored in the digital control terminal 2. It judges whether the distribution circuit meets the protection control conditions based on the current signal collected by the current transformer 1. When the conditions are met, a protection control signal is generated and sent to the circuit breaker 3 to instruct the circuit breaker operating component to perform a tripping operation.

[0036] Optionally, to make the power distribution protection system more intelligent, after a set time period after the circuit breaker 3's circuit breaker operating component performs an opening operation, the digital control terminal 2 generates a reclosing control signal and sends it to the circuit breaker 3's circuit breaker operating component to perform a closing operation.

[0037] Furthermore, the circuit breaker operating component includes a shunt release or an electric operating mechanism.

[0038] Optionally, the electric operating mechanism includes a closing coil and an opening coil.

[0039] Furthermore, the circuit breaker 3 has multiple output terminals, and there are multiple current transformers 1 , and the number of the current transformers 1 is consistent with the number of the output terminals of the circuit breaker 3 .

[0040] It should be noted that, in this embodiment, the circuit breaker 3 can be configured as a circuit breaker with magnetic tripping and thermal tripping functions.

[0041] The circuit breaker 3 can provide short-circuit protection for the power distribution system through magnetic tripping and overload protection through thermal tripping.

[0042] Furthermore, the power distribution protection system of this embodiment may be arranged in a power distribution cabinet to protect a power distribution circuit connected to the power distribution cabinet.

[0043] It should be noted that the power distribution protection system of this embodiment can be arranged in a power distribution system, such as a distribution box, a distribution cabinet or a cable shaft.

[0044] Embodiment 2

[0045] Reference Figure 2 , shows a flow chart of the steps of a power distribution protection method provided by Embodiment 2 of the present invention, which can be implemented as follows Figure 1 The power distribution protection system shown or the terminal device including the power distribution protection system executes the power distribution protection method. Specifically, the power distribution protection method of this embodiment may include the following steps:

[0046] Step 202: Obtain current data of the power distribution circuit.

[0047] The current data in the measured low-voltage power distribution system can be collected by current transformers such as shunts, electromagnetic current transformers, electronic current transformers, etc.

[0048] The current transformer transmits the collected current data to the digital control terminal, and the digital control terminal processes the received current data (such as sampling, conversion, etc.) to obtain the current data in the distribution circuit to be detected.

[0049] Step 204: Determine whether the power distribution circuit meets the protection control condition based on the current data. If it is determined that the protection control condition is met, execute step 206, otherwise end this process.

[0050] The digital control terminal uses the acquired current data in the power distribution circuit as a basis for judging whether the power distribution circuit meets the protection control conditions. When it is determined that the protection control conditions are met, step 206 is executed.

[0051] It should be noted that the protection control conditions include: the distribution circuit meets the overload protection condition and / or the distribution circuit meets the short-circuit protection condition.

[0052] Step 206: Send a protection control signal to the circuit breaker to instruct the circuit breaker's circuit breaking operation component to perform a circuit breaking operation.

[0053] When it is determined that the power distribution circuit meets the protection control condition, a protection control signal is generated and sent to the circuit breaker, instructing the circuit breaker's circuit breaking operation component to perform a circuit breaking operation.

[0054] The power distribution protection method provided by the embodiment of the present invention obtains the current data of the power distribution circuit, and determines whether the power distribution circuit meets the protection control condition according to the current data. When it is determined that the protection control condition is met, a protection control signal is sent to the circuit breaker to instruct the circuit breaker's circuit breaking operation component to perform a circuit breaking operation, thereby performing intelligent protection on the power distribution circuit. In this way, dual protection is achieved for the power distribution system on the basis of performing protection by utilizing the physical properties of the circuit breaker itself.

[0055] Embodiment 3

[0056] Reference Figure 3 , shows a flow chart of the steps of a power distribution protection method provided by Embodiment 3 of the present invention, which can be implemented as follows Figure 1 The power distribution protection system shown or the terminal device including the power distribution protection system executes the power distribution protection method. Specifically, the power distribution protection method of this embodiment may include the following steps:

[0057] Step 302: Obtain current data of the power distribution circuit.

[0058] The current data in the measured low-voltage power distribution system can be collected through current transformers such as shunts, electromagnetic current transformers, electronic current transformers, etc.

[0059] Step 304: Sample the current data to obtain a sampled current value.

[0060] The current data may be, but is not limited to: a pulse signal or a waveform signal of the current, and the current data is sampled to obtain a sampled current value of the current data.

[0061] Step 306: Determine whether the power distribution circuit meets the protection control condition according to the sampled current value. If it is determined that the protection control condition is met, execute step 308, otherwise end this process.

[0062] The protection control conditions in this embodiment include: the power distribution circuit meets the overload protection condition and / or the power distribution circuit meets the short circuit protection condition.

[0063] The steps for judging overload protection conditions are as follows:

[0064] The sampled current value is converted and calculated, such as performing A / D conversion (Analog to Digital converter) on the sampled current to obtain a digital signal corresponding to the sampled current, taking its absolute value, and then summing the absolute values ​​of the digital signals within one cycle, and determining the average current value within one cycle. The sampling interval T can be 1 / 64 of a cycle time. For example, when the frequency is 50 Hz, the time of one cycle is 20 ms, and the sampling interval T is 0.3125 ms.

[0065] If the average current value of any first cycle is greater than the first current threshold, the heat value generated by the current in multiple consecutive cycles is accumulated and counted starting from the first cycle, and the average current value of the multiple consecutive cycles is not less than the second current threshold; when the accumulated heat value exceeds the set heat threshold, it is determined that the distribution circuit meets the overload protection condition.

[0066] Specifically, the average current value Ia in one cycle is converted into the actual average current value Ioa, which can be calculated by the following formula:

[0067] Ioa=Ia*K;

[0068] Among them, K is the current conversion coefficient, and the current conversion coefficient can be set according to the current and voltage measurement range and the analog-to-digital conversion bit number of the actual circuit. For example, when the current measurement range is 0 to 100A and the analog-to-digital conversion bit number is 12 bits, K is 0.04883, which is not specifically limited in this embodiment.

[0069] In this embodiment, the digital distribution terminal sets the long delay setting value (Ir) and the long delay setting action time (Tr, unit is 20ms), and then calculates the following three protection threshold parameters based on these two parameters, that is, setting the first current threshold, the second current threshold and the heat threshold.

[0070] The first current threshold Ith (i.e., the heat accumulation start threshold current) can be calculated using the following formula:

[0071] Ith=K1*Ir

[0072] Among them, K1=1.2.

[0073] The second current threshold Itl (i.e., the heat accumulation end threshold current) can be calculated using the following formula:

[0074] It1=K2*Ir

[0075] Among them, K2=1.05.

[0076] The heat threshold Qth (i.e., the heat accumulation thermal trip threshold) can be calculated using the following formula:

[0077] Qth = (Ir * K3) 2 * Tr,

[0078] where 3 < K3 < 9, such as K3 = 6.

[0079] where the accumulated statistical heat value can be obtained by the following calculation formula:

[0080] Qsum n = Qsum n-1 + Ioa 2

[0081] The judgment steps for the short - circuit protection condition are as follows:

[0082] Determine the change slope value of the sampled current value based on the sampled current value,

[0083] If it is determined that the change slope value of the sampled current value of the first consecutive number exceeds the set slope threshold, then it is determined that the distribution circuit meets the short - circuit protection condition.

[0084] And / or,

[0085] Determine the instantaneous current value based on the sampled current value,

[0086] If the instantaneous current value of the second consecutive number exceeds the third current threshold, then it is determined that the distribution circuit meets the short - circuit protection condition.

[0087] For example, when the change slope values of n consecutive sampled currents exceed the set slope threshold, then it is determined that the distribution circuit meets the short - circuit protection condition, where 4 < n < 9 and n is an integer, such as n = 5.

[0088] When the instantaneous current values of m consecutive numbers exceed the set third current threshold, then it is determined that the distribution circuit meets the short - circuit protection condition, where 5 < m < 10 and m is an integer, such as m = 6.

[0089] Step 308: Send a protection control signal to the circuit breaker to instruct the opening operation component of the circuit breaker to perform an opening operation.

[0090] When it is determined that the distribution circuit meets the protection control condition, generate a protection control signal and send it to the circuit breaker, instructing the opening operation component of the circuit breaker to perform an opening operation.

[0091] In an alternative solution of this embodiment, when the digital control terminal fails, the circuit breaker can also perform short - circuit protection on the distribution circuit through its magnetic trip, and can also perform overload protection on the distribution circuit through its thermal trip.

[0092] The power distribution protection method provided by the embodiment of the present invention obtains the current data of the power distribution circuit, and determines whether the power distribution circuit meets the protection control condition according to the current data. When it is determined that the protection control condition is met, a protection control signal is sent to the circuit breaker to instruct the circuit breaker's circuit breaking operation component to perform the circuit breaking operation, and the power distribution circuit is effectively protected by digital intelligent protection through the digital control terminal. Therefore, on the basis of using the physical properties of the circuit breaker itself to perform protection, dual protection is achieved for the power distribution system.

[0093] The embodiment of the present invention further provides a power distribution device, including the power distribution protection system in the first embodiment, which can also realize double protection of the power distribution system, and will not be described in detail.

[0094] An embodiment of the present invention further provides a power distribution system, including the above-mentioned power distribution equipment, which can also achieve double protection for the power distribution system, which will not be described in detail.

[0095] Those skilled in the art will understand that in the above method of the specific implementation mode of the embodiment of the present invention, the serial number of each step does not mean the order of execution. The execution order of each step should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the specific implementation mode of the embodiment of the present invention.

[0096] It should be pointed out that, according to the needs of implementation, the various components / steps described in the embodiments of the present invention can be split into more components / steps, or two or more components / steps or partial operations of components / steps can be combined into new components / steps to achieve the purpose of the embodiments of the present invention.

[0097] The above-described method according to an embodiment of the present invention may be implemented in hardware, firmware, or as software or computer code that can be stored in a recording medium (such as a CD ROM, RAM, floppy disk, hard disk, or magneto-optical disk), or as computer code that is originally stored in a remote recording medium or a non-temporary machine-readable medium downloaded through a network and will be stored in a local recording medium, so that the method described herein may be stored in such software processing on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It is understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by a computer, a processor, or hardware, the power distribution protection processing method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the power distribution protection processing shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the power distribution protection processing shown herein.

[0098] Those of ordinary skill in the art will appreciate that the units and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of the present invention.

[0099] The above implementation methods are only used to illustrate the embodiments of the present invention, and are not limitations of the embodiments of the present invention. Ordinary technicians in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present invention. The patent protection scope of the embodiments of the present invention should be defined by the claims.

Claims

1. A power distribution protection system, characterized in that: It comprises a current transformer (1), a digital control terminal (2) and a circuit breaker (3); The input end of the circuit breaker (3) is connected to a power distribution bus (4), the output end of the circuit breaker (3) is connected to a power distribution circuit (5), the current transformer (1) is also provided on the power distribution circuit side of the circuit breaker (3), the digital control terminal (2) is respectively connected to the circuit breaker (3) and the current transformer (1), and the circuit breaker (3) has a circuit breaker operating component; The current transformer (1) is used to collect the current signal of the power distribution circuit (5) and transmit the current signal to the digital control terminal (2); The digital control terminal (2) is used to generate a protection control signal according to the current signal collected by the current transformer (1), and send the protection control signal to the circuit breaker (3) of the circuit breaker; The circuit breaker operating component is used to perform closing or opening operations according to the protection control signal. Wherein, the digital control terminal (2) is specifically used for: Obtain current data of power distribution circuits; Sampling the current data to obtain a sampled current value; Determining whether the power distribution circuit meets a protection control condition according to the current data, the protection control condition including: the power distribution circuit meets an overload protection condition and / or the power distribution circuit meets a short circuit protection condition; When the conditions are met, a protection control signal is sent to the circuit breaker (3) to instruct the circuit breaker (3) of the circuit breaker to perform a circuit breaker operation. Wherein, judging whether the power distribution circuit meets the protection control condition according to the current data includes: Determine the average current value of the current in each cycle according to the sampled current value; If the average current value of any first cycle is greater than the first current threshold, the heat value generated by the current in a plurality of consecutive cycles is accumulated and counted starting from the first cycle, and the average current value of the plurality of consecutive cycles is not less than the second current threshold; When the cumulative heat value exceeds the set heat threshold, it is determined that the power distribution circuit meets the overload protection condition. The first current threshold is calculated according to the following formula: , and calculate the second current threshold according to the following formula , Ir is the long delay setting value; Among them, the heat threshold is calculated according to the following formula , 3 < K3 < 9, and Tr is the long-delay setting operation time; The heat values ​​generated by the current in a plurality of consecutive cycles are accumulated and counted starting from the first cycle, including: According to the following formula, the average current value Ia of any cycle is converted into the actual average current value , where K is the current conversion coefficient; The heat value Qsum generated by the current in n consecutive cycles is accumulated and counted according to the following formula n :Qsum n =Qsum n-1 +Ioa 2 .

2. The system according to claim 1, characterized in that The current transformer (1) is arranged on the power distribution circuit (5).

3. The system according to claim 1, characterized in that The circuit breaker operating component includes a shunt release or an electric operating mechanism.

4. The system according to claim 3, characterized in that The electric operating mechanism comprises a closing coil and an opening coil.

5. The system according to any one of claims 1 to 4, characterized in that: The circuit breaker (3) has a plurality of output terminals, the current transformers (1) are a plurality, and the number of the current transformers (1) is consistent with the number of the output terminals of the circuit breaker (3).

6. The system according to any one of claims 1 to 4, characterized in that: The power distribution protection system is arranged in the power distribution system.

7. A power distribution device, characterized in that: It comprises a power distribution protection system as described in any one of claims 1 to 6.

8. A power distribution system, characterized in that: Comprising at least one power distribution device as claimed in claim 7.

9. A power distribution protection method for a power distribution protection system as claimed in any one of claims 1 to 6, characterized in that: include: Obtain current data of power distribution circuits; Sampling the current data to obtain a sampled current value; Determining whether the power distribution circuit meets a protection control condition according to the current data, the protection control condition including: the power distribution circuit meets an overload protection condition and / or the power distribution circuit meets a short circuit protection condition; When the conditions are met, a protection control signal is sent to the circuit breaker to instruct the circuit breaker's circuit breaking operation component to perform a circuit breaking operation. Wherein, judging whether the power distribution circuit meets the protection control condition according to the current data includes: Determine the average current value of the current in each cycle according to the sampled current value; If the average current value of any first cycle is greater than the first current threshold, the heat value generated by the current in a plurality of consecutive cycles is accumulated and counted starting from the first cycle, and the average current value of the plurality of consecutive cycles is not less than the second current threshold; When the cumulative heat value exceeds the set heat threshold, it is determined that the power distribution circuit meets the overload protection condition. The first current threshold is calculated according to the following formula: , and calculate the second current threshold according to the following formula , Ir is the long delay setting value; Among them, the heat threshold is calculated according to the following formula , 3 < K3 < 9, and Tr is the long-delay setting operation time; The heat values ​​generated by the current in a plurality of consecutive cycles are accumulated and counted starting from the first cycle, including: According to the following formula, the average current value Ia of any cycle is converted into the actual average current value , where K is the current conversion coefficient; The heat value Qsum generated by the current in n consecutive cycles is accumulated and counted according to the following formula n :Qsum n =Qsum n-1 +Ioa 2 .

10. The method according to claim 9, characterized in that The determining whether the power distribution circuit meets the protection control condition according to the current data further includes: Determine a change slope value of the sampling current value based on the sampling current value, If it is determined that the change slope value of the first number of consecutive sampling current values ​​exceeds the set slope threshold, it is determined that the power distribution circuit meets the short-circuit protection condition.

11. The method according to claim 9, characterized in that The determining whether the power distribution circuit meets the protection control condition according to the current data further includes: determining an instantaneous current value based on the sampled current value, If a second number of consecutive instantaneous current values ​​exceed a third current threshold, it is determined that the power distribution circuit meets a short circuit protection condition.

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