Method, system and equipment for evaluating performance of system frequency modulation participated by adjustable load and giving consideration to influence of communication system

Abstract

The invention discloses a method, a system and equipment for evaluating the performance of an adjustable load participating in system frequency modulation by considering the influence of a communication system, and the method comprises the steps: evaluating the communication time delay of the adjustable load participating in the primary frequency modulation process of a power grid, and determining the communication time delays of the adjustable load under different communication conditions; introducing the communication time delay into a frequency adjustment model of the load, and establishing a generator and adjustable load frequency response mathematical model; and based on the generator rotor dynamic equation and the generator and adjustable load frequency response model, deducing an adjustable load frequency regulation performance ratio considering the communication time delay. According to the method, the influence of communication delay on the load frequency regulation performance is systematically analyzed, and theoretical support is provided for optimization of the load participation degree in the power grid frequency regulation process. Through comprehensive analysis of communication time delay and load response characteristics, a load aggregator is helped to better evaluate effectiveness of load resources in primary frequency modulation, an auxiliary decision is provided for a power dispatching department, and configuration of power grid frequency modulation resources is optimized.

Description

Technical Field

[0001] The present invention belongs to the field of power system frequency regulation, and specifically relates to a method, system and device for evaluating the frequency regulation performance of an adjustable load participating in a system taking into account the influence of a communication system. Background Art

[0002] With the continuous development of power systems and the increasing demand for efficient and stable grid operation, the participation of adjustable loads in primary frequency regulation has become an important means to improve the frequency stability of the grid. In the process of primary frequency regulation, the rapid response capability of the load has a direct impact on the frequency regulation performance of the grid. At present, traditional methods mainly rely on the frequency response model of the generator set, focusing on the frequency regulation performance on the power generation side, while there is a lack of in-depth research on the response characteristics of adjustable loads. In particular, when adjustable loads participate in frequency response through communication networks, the impact of communication delay is often ignored. This neglect may lead to the following problems: First, communication delay will cause a lag in the response of adjustable loads, affecting the real-time and accuracy of frequency regulation; second, the load response model that fails to accurately model the communication delay may overestimate the actual regulation capability of the load, resulting in improper resource allocation; finally, the lack of evaluation of the impact of delay may lead to insufficient stability and robustness of the frequency response model, and poor dynamic response performance when the system is disturbed. Summary of the invention

[0003] Purpose of the invention: The present invention aims to provide a method for evaluating the frequency regulation performance of an adjustable load participating in a system taking into account the communication delay and the influence of the communication system; another purpose of the present invention is to provide a system and device for evaluating the frequency regulation performance of an adjustable load participating in a system taking into account the influence of the communication system.

[0004] The present invention can not only help load aggregators better evaluate the effectiveness of load resources in primary frequency regulation, but also provide auxiliary decision-making for power dispatching departments and optimize the configuration of power grid frequency regulation resources. The method can further refine the evaluation of load regulation performance and improve the utilization efficiency of adjustable load resources in the power grid, thereby achieving more stable and efficient power grid frequency regulation.

[0005] Technical solution: The method for evaluating the frequency modulation performance of the adjustable load participating in the system taking into account the influence of the communication system described in the present invention comprises the following steps:

[0006] (1) Determine the communication delay of adjustable loads participating in the primary frequency regulation of the power grid based on inherent delay, transmission delay, propagation delay and queuing delay;

[0007] (2) Introducing communication delay into the frequency response model of the adjustable load, and establishing the frequency response model of the generator and the adjustable load;

[0008] (3) Based on the generator rotor dynamic equation and the generator and adjustable load frequency response model, determine the adjustable load frequency response performance ratio that takes into account communication delay.

[0009] Furthermore, in step (1), the communication delay T of the adjustable load participating in the primary frequency regulation of the power grid is

[0010] T=T1+T2+T3+T4

[0011] In the formula, T1 is the inherent delay; T2 is the transmission delay; T3 is the propagation delay; and T4 is the queuing delay.

[0012] Furthermore, the inherent delay T1 is

[0013] T1=d1+d2+h·d3

[0014] Where d1 is the delay caused by the sending device to package the data; d2 is the delay caused by the receiving device to unpack the data packet; d3 is the inherent delay of the base station node through which the transmission passes; h is the number of base station nodes from the sending end to the receiving end;

[0015] The transmission delay T2 is

[0016]

[0017] Where L is the size of the node downlink data packet; r is the transmission rate; b is the channel bandwidth; P is the data packet transmission power; G is the channel gain; σ is the transmission noise;

[0018] The propagation delay T3 is

[0019]

[0020] Where: x is the distance between the source node and the destination node; v is the propagation speed of the signal;

[0021] The queuing delay T4 is

[0022]

[0023] Where: L k is the total queue length; i For node v i The packet arrival rate; ρ i For node v i Utilization rate; E(Q i ) is the node v i The average queue length of data packets; μ i The service rate.

[0024] Furthermore, in step (2), the frequency response process of the generator and the adjustable load is divided into frequency response when the system frequency decreases and frequency response when the system frequency increases.

[0025] Furthermore, in step (2), when the system frequency decreases, the frequency response model of the generator and the adjustable load is

[0026]

[0027] In the formula, ΔP g+ (t) is the generator frequency response reserve when the system frequency decreases; R g+ t sg +t g The maximum active output of the generator set for frequency regulation is reached at the moment; t sg is the generator response time; t g is the generator adjustment time; ΔP l+ (t) is the adjustable load frequency response reserve when the system frequency decreases; R l+ t sl +T+t l The maximum load shedding capacity for frequency regulation is reached at the moment; t sl is the adjustable load response time; t l is the adjustable load adjustment time; t1 is the total frequency regulation time.

[0028] Furthermore, in step (2), when the system frequency increases, the frequency response model of the generator and the adjustable load is

[0029]

[0030] In the formula, ΔP g- (t) is the generator frequency response reserve when the system frequency increases; R g- t sg +t g The minimum active output of the generator set for frequency regulation is reached at the moment; ΔP l- (t) is the adjustable load frequency response reserve when the system frequency decreases; R l- t sl +T+t l The maximum load shedding capacity for frequency regulation is reached at all times.

[0031] Furthermore, in step (3), when the system frequency decreases, the generator and adjustable load frequency response model are combined with the generator rotor motion equation to obtain the frequency dynamic model as follows:

[0032]

[0033] Where: M represents the inertia constant of the power system; Δf(t) represents the frequency deviation; D represents the load damping coefficient; ΔP L represents sudden power loss; g is the number of generators; l is the number of adjustable loads.

[0034] The adjustable load frequency response performance ratio when the system frequency decreases is X + for

[0035]

[0036] Furthermore, in step (3), when the system frequency increases, the generator and adjustable load frequency response model are combined with the generator rotor motion equation to obtain the frequency dynamic model as follows:

[0037]

[0038] The adjustable load frequency response performance ratio when the system frequency increases is X - for

[0039]

[0040] The evaluation system for the frequency regulation performance of the adjustable load participating in the system taking into account the influence of the communication system of the present invention comprises:

[0041] Data acquisition module, used to collect time delay data and motor group parameter data;

[0042] A model building module is used to build a frequency response model of an adjustable load with communication delay, a generator and adjustable load frequency response model, and a frequency dynamic model;

[0043] The calculation module is used to calculate the frequency response performance ratio of the adjustable load when the system frequency decreases or increases.

[0044] The computer device of the present invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the steps of the above method are implemented when the processor executes the computer program.

[0045] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: 1. The present invention systematically evaluates the influence of communication delay on the participation of adjustable loads in the primary frequency regulation process, comprehensively considers multiple factors such as inherent delay, transmission delay, propagation delay and queuing delay, and calculates the comprehensive communication delay index under different communication conditions through quantitative analysis; 2. The present invention introduces communication delay into the frequency response model of the adjustable load, establishes a more accurate generator and adjustable load frequency response model, and makes the evaluation of frequency regulation performance more comprehensive and precise; 3. Based on the generator rotor dynamic equation and the generator and adjustable load frequency response model, the present invention derives the adjustable load frequency regulation performance ratio taking into account the communication delay, and provides a theoretical basis for optimizing the configuration of adjustable load resources in the grid frequency regulation process; 4. It is helpful to accurately evaluate the effectiveness of adjustable loads in the primary frequency regulation of the grid, and provide auxiliary decision-making for the power dispatching department to optimize the configuration of grid frequency regulation resources, thereby improving the stability and efficiency of grid frequency regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a flow chart of the present invention;

[0047] Figure 2 It is a schematic diagram of the frequency response model of the generator and the adjustable load;

[0048] Figure 3 A comparison chart of the performance ratio of industrial load frequency response. DETAILED DESCRIPTION

[0049] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0050] like Figure 1 As shown, the method for evaluating the frequency modulation performance of the adjustable load participating in the system taking into account the influence of the communication system according to the present invention comprises the following steps:

[0051] S1. Based on factors such as inherent delay, transmission delay, propagation delay and queuing delay, the communication delay of adjustable loads participating in the primary frequency regulation of the power grid is evaluated:

[0052] When the frequency of the power system shifts, the adjustable load can participate in a frequency regulation by successfully bidding for the frequency regulation capacity in the frequency regulation market. At this time, the power system will issue a power regulation command to the adjustable load. There is a certain communication delay between the issuance of the command and the reception of the command by the adjustable load. Communication delay refers to the time required for a message or command to be transmitted from one end of a network to the other end, which generally includes inherent delay, transmission delay, propagation delay and queuing delay. The set of nodes in the communication network is represented by V = {v0, v1, ..., v m}, and there is only one link between the two nodes. The source node sends N data streams to the destination node, and the data streams all follow the optimal path P kTransmission, suppose any data stream f k (k=1, 2, ..., N) on path P k The number of base station nodes transmitted is h.

[0053] (1) Intrinsic delay

[0054] Intrinsic delay refers to the delay related to the performance of the communication equipment itself, also known as processing delay or node delay. This delay mainly includes the time consumed by network devices such as routers and switches when processing data packets. Specifically, it includes the time for checking, processing, encapsulating and decapsulating data packets. Intrinsic delay is usually very small and fixed, only a few microseconds. The inherent delay T1 can be expressed by the formula:

[0055] T1=d1+d2+h·d3 (1)

[0056] Where: d1 represents the delay caused by the sending device to package the data; d2 represents the delay caused by the receiving device to unpack the data packet; d3 represents the inherent delay of the base station node through which the transmission passes; h represents the number of base station nodes passed from the sending end to the receiving end.

[0057] (2) Transmission delay

[0058] Transmission delay is the time required for a host or router to send a data frame, that is, the time required from the first bit of the data frame to the last bit of the data frame. It depends on the size of the data packet and the transmission rate. According to Shannon's theorem, the transmission delay T2 can be expressed as:

[0059]

[0060] Where: L represents the size of the node downlink data packet; r represents the transmission rate; b represents the channel bandwidth; P represents the data packet transmission power; G represents the channel gain; σ represents the transmission noise.

[0061] (3) Propagation delay

[0062] Propagation delay is the time it takes for a data signal to travel in a transmission medium. Its value is related to the physical properties of the transmission medium and the propagation distance. The propagation delay T3 can be expressed as:

[0063]

[0064] Where: x represents the distance between the source node and the destination node; v represents the propagation speed of the signal. The propagation speed of the optical signal in the optical fiber is 2 / 3 of the speed of light, that is, 2×10 8 m / s.

[0065] (4) Queuing Delay

[0066] Queuing delay is the time that a data packet waits in a queue in a node (such as a router or switch) for processing. When the network load is high, the data packet may need to wait for service in a buffer queue, resulting in queuing delay. Queuing delay is affected by many factors such as network traffic, queue length, and service strategy, and is the most unstable part of the delay. Under high load conditions, queuing delay may increase significantly, which has a greater impact on the overall delay of the communication system. When analyzing queuing delay, the M / M / 1 queuing model is a commonly used mathematical model that can effectively describe the behavior of a single-server queuing system. In the M / M / 1 queuing model, the arrival process follows a Poisson distribution, the service time follows an exponential distribution, and there is only one server in the system. The service order of all power system services in the network follows the first-come, first-served principle and has the same priority. For node v i , the packet arrival rate is λ i , the service rate is μ i . Node v i The utilization rate ρ i for:

[0067]

[0068] Node v i The average queue length of data packets E(Q i ) can be expressed as:

[0069]

[0070] Because each node in the network is independent of each other, f k On path P k The total queue length on is the sum of the queue lengths of each base station node, and the total queue length is expressed as:

[0071]

[0072] According to Little's theorem, the queuing delay can be expressed as:

[0073]

[0074] In summary, the communication delay T of the adjustable load participating in a frequency modulation process can be expressed as:

[0075] T=T1+T2+T3+T4 (9)

[0076] Where: T represents communication delay; T1 represents inherent delay; T2 represents transmission delay; T3 propagation delay; T4 represents queuing delay.

[0077] S2. Introduce the above communication delay into the frequency response model of the adjustable load, and establish a mathematical model of the frequency response of the generator and the adjustable load:

[0078] The frequency response process of the generator and the adjustable load is divided into two cases, namely, frequency response when the system frequency decreases and frequency response when the system frequency increases.

[0079] (1) When the system frequency decreases

[0080] like Figure 2 As shown in Figure 1, it is assumed that the system frequency drops at time t0 and deviates from the normal level. In order to restore the frequency stability, the system will rebalance the supply and demand relationship through a frequency adjustment. sg When the frequency deviation reaches Δf sg , the generator starts to provide active output to increase the system frequency. sg +t g The maximum active output R of the generator set for frequency regulation is reached at any time g+ ; at t sl +T time the frequency deviation reaches Δf sl , the adjustable load is shedding the load by bidding the frequency regulation capacity successfully in the frequency regulation market. sl +T+t l The maximum load shedding capacity R for frequency regulation is reached at any time l+ Through the regulation of generators and adjustable loads, the system frequency is pulled back to normal levels at time t1 to ensure the stability and continuous operation of the system.

[0081] Based on the above analysis, the frequency response model of the generator and adjustable load when the system is reduced is established:

[0082]

[0083] Where ΔP g+ (t) is the generator frequency response reserve when the system frequency decreases; R g+ t sg +t g The maximum active output of the generator set for frequency regulation is reached at the moment; t sg is the generator response time; t g is the generator adjustment time; ΔP l+ (t) is the adjustable load frequency response reserve when the system frequency decreases; R l+ t sl +T+t l The maximum load shedding capacity for frequency regulation is reached at the moment; t sl is the adjustable load response time; t l is the adjustable load adjustment time; t1 is the total frequency regulation time.

[0084] (2) When the system frequency increases

[0085] like Figure 2 As shown in Figure 1, it is assumed that the system frequency rises at time t0 and deviates from the normal level. In order to restore the stability of the frequency, the system will rebalance the supply and demand relationship through a frequency adjustment. sg When the frequency deviation reaches Δf sg , the generator starts to reduce its active output to lower the system frequency. sg +t g The minimum active output R of the generator set for frequency regulation is reached at any time g- ; at t sl +T time frequency deviation reaches Δf sl , the adjustable load increases the load by bidding successfully for the frequency regulation capacity in the frequency regulation market. sl +T+t l The maximum load increase R for frequency regulation is reached at any time l- Through the regulation of generators and adjustable loads, the system frequency is pulled back to normal levels at time t1 to ensure the stability and continuous operation of the system.

[0086] Based on the above analysis, the generator and adjustable load frequency response model when the system is increased is established:

[0087]

[0088] In the formula, ΔP g- (t) is the generator frequency response reserve when the system frequency increases; R g- t sg +t g The minimum active output of the generator set for frequency regulation is reached at the moment; ΔP l- (t) is the adjustable load frequency response reserve when the system frequency decreases; R l- t sl +T+t l The maximum load shedding capacity for frequency regulation is reached at all times.

[0089] S3. Based on the generator rotor dynamic equation and the generator and adjustable load frequency response model, the adjustable load frequency response performance ratio taking into account the communication delay is derived:

[0090] The performance ratio of the adjustable load is divided into two cases, namely, the performance ratio of the adjustable load when the system frequency decreases and the performance ratio of the adjustable load when the system frequency increases.

[0091] (1) When the system frequency decreases

[0092] The frequency dynamic model can be obtained from the generator rotor motion equation:

[0093]

[0094] Where: Δf(t) represents the frequency deviation; D represents the load damping coefficient; M represents the inertia constant of the power system; ΔP L Indicates a sudden power loss.

[0095] According to the generator and adjustable load model when the frequency is reduced established in step S2, the frequency deviation in different time periods can be derived. sg ] During this period, solving equation (14) yields:

[0096]

[0097] In [t sg , t sl +T], solving equation (14) yields:

[0098]

[0099] At time t1, the system frequency reaches a steady state. Solving equation (14), we can obtain:

[0100]

[0101] In summary, the integrated frequency deviation can be obtained:

[0102]

[0103] In the above formula, X + It is defined as the performance ratio of adjustable load, and its specific expression is:

[0104]

[0105] X + It can reflect the frequency response performance of the adjustable load relative to the generator in the primary frequency regulation. In formula (18), R g+ and R l+ The coefficients of reflect how much the integral frequency deviation can be reduced by increasing the generator frequency reserve by 1MW and the adjustable load frequency reserve by 1MW. + It can be explained as follows: In terms of reducing the integral frequency deviation, the adjustable load frequency reserve is X of the upward generator frequency reserve. + times, which reflects the importance of faster response rates.

[0106] (2) When the system frequency increases

[0107] When the system frequency increases, the generator and adjustable load frequency response model are combined with the generator rotor motion equation to obtain the frequency dynamic model:

[0108]

[0109] According to the performance ratio derivation steps when the system frequency decreases, the adjustable load performance ratio X when the system frequency increases can be calculated. - , its specific expression is:

[0110]

[0111] In order to verify the effectiveness and rationality of the frequency regulation performance evaluation method of adjustable loads taking into account the influence of the communication system proposed in this invention, we use the IEEE39 node system to verify the proposed model. The load damping constant D per Hz is assumed to be 2% of the total load demand; the inertia constant M is set to 500MW·s / Hz; t1 is set to 30s. Four industrial loads are selected as load frequency regulation reserve providers, and their industrial types, location nodes, and distances from the leading node are shown in the following table:

[0112]

[0113] Based on the system data and the calculation formulas for inherent delay, transmission delay, propagation delay and queuing delay, the communication delay of four industrial loads can be calculated, as shown in the following table:

[0114]

[0115] According to existing literature research, the electrolytic aluminum adjustment time t is set l0 =3s, ferroalloy adjustment time t l1 =6s, calcium carbide adjustment time t l2 =4s, cement adjustment time t l3 =0.1s; Generator adjustment time t g =5s; Generator response time t sg =0.1-0.2s, the performance ratio of the four industrial load frequency responses can be obtained through the performance ratio calculation formula, such as Figure 3 The dotted curve in the figure represents the adjustable load performance ratio without considering the communication delay, and the solid curve represents the adjustable load performance ratio considering the communication delay. Considering the communication delay will make the evaluation of the frequency regulation response more comprehensive and precise.

[0116] In summary, this invention systematically evaluates the impact of communication delay on the participation of adjustable loads in primary frequency regulation, and comprehensively considers factors such as inherent delay, transmission delay, propagation delay, and queuing delay. Through quantitative analysis, the comprehensive communication delay index under different communication conditions is calculated, and the communication delay is introduced into the frequency regulation model, and a more accurate frequency response mathematical model of the generator and adjustable load is established, so as to more comprehensively and finely evaluate the frequency regulation performance. This method not only helps load aggregators to more accurately evaluate the effectiveness of load resources in primary frequency regulation, but also provides the power dispatching department with an auxiliary decision-making basis for optimizing the configuration of power grid frequency regulation resources.

Claims

1. A method for evaluating the frequency regulation performance of adjustable loads participating in a system taking into account the influence of a communication system, characterized in that: The following steps are involved: (1) Determine the communication delay of adjustable loads participating in the primary frequency regulation of the power grid based on inherent delay, transmission delay, propagation delay and queuing delay; (2) Introducing communication delay into the frequency response model of the adjustable load, and establishing the frequency response model of the generator and the adjustable load; (3) Based on the generator rotor dynamic equation and the generator and adjustable load frequency response model, determine the adjustable load frequency response performance ratio that takes into account communication delay.

2. The method for evaluating the frequency modulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 1 is characterized in that: In step (1), the communication delay T of the adjustable load participating in the primary frequency regulation process of the power grid is T=T1+T2+T3+T4 In the formula, T1 is the inherent delay; T2 is the transmission delay; T3 is the propagation delay; and T4 is the queuing delay.

3. The method for evaluating the frequency modulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 2 is characterized in that: The inherent delay T1 is T1=d1+d2+h·d3 Where d1 is the delay caused by the sending device to package the data; d2 is the delay caused by the receiving device to unpack the data packet; d3 is the inherent delay of the base station node through which the transmission passes; h is the number of base station nodes from the sending end to the receiving end; The transmission delay T2 is Where L is the size of the node downlink data packet; r is the transmission rate; b is the channel bandwidth; P is the data packet transmission power; G is the channel gain; σ is the transmission noise; The propagation delay T3 is Where: x is the distance between the source node and the destination node; v is the propagation speed of the signal; The queuing delay T4 is Where: L k is the total queue length; i For node v i The packet arrival rate; ρ i For node v i Utilization rate; E(Q i ) is the node v i The average queue length of data packets; μ i The service rate.

4. The method for evaluating the frequency modulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 3 is characterized in that: In step (2), the frequency response process of the generator and the adjustable load is divided into frequency response when the system frequency decreases and frequency response when the system frequency increases.

5. The method for evaluating the frequency modulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 4 is characterized in that: In step (2), when the system frequency decreases, the frequency response model of the generator and adjustable load is In the formula, ΔP g+ (t) is the generator frequency response reserve when the system frequency decreases; R g+ t sg +t g The maximum active output of the generator set for frequency regulation is reached at the moment; t sg is the generator response time; t g is the generator adjustment time; ΔP l+ (t) is the adjustable load frequency response reserve when the system frequency decreases; R l+ t sl +T+t l The maximum load shedding capacity for frequency regulation is reached at the moment; t sl is the adjustable load response time; t l is the adjustable load adjustment time; t1 is the total frequency regulation time.

6. The method for evaluating the frequency regulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 4 is characterized in that: In step (2), when the system frequency increases, the frequency response model of the generator and adjustable load is In the formula, ΔP g- (t) is the generator frequency response reserve when the system frequency increases; R g- t sg +t g The minimum active output of the generator set for frequency regulation is reached at the moment; ΔP l- (t) is the adjustable load frequency response reserve when the system frequency decreases; R l- t sl +T+t l The maximum load shedding capacity for frequency regulation is reached at the moment; t sg is the generator response time; t g is the generator adjustment time; t sl is the adjustable load response time; t l is the adjustable load adjustment time; t1 is the total frequency regulation time.

7. The method for evaluating the frequency regulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 5, characterized in that: In step (3), when the system frequency decreases, the generator and adjustable load frequency response model are combined with the generator rotor motion equation to obtain the frequency dynamic model as follows: Where: M represents the inertia constant of the power system; Δf(t) represents the frequency deviation; D represents the load damping coefficient; ΔP L represents sudden power loss; g is the number of generators; l is the number of adjustable loads. The adjustable load frequency response performance ratio when the system frequency decreases is X + for 8. The method for evaluating the frequency regulation performance of adjustable loads participating in the system taking into account the influence of the communication system according to claim 6, characterized in that: In step (3), when the system frequency increases, the generator and adjustable load frequency response model are combined with the generator rotor motion equation to obtain the frequency dynamic model as follows: The adjustable load frequency response performance ratio when the system frequency increases is X - for 9. An evaluation system for frequency regulation performance of adjustable load participating in a system taking into account the influence of a communication system, characterized in that: include Data acquisition module, used to collect time delay data and motor group parameter data; A model building module is used to build a frequency response model of an adjustable load with communication delay, a generator and adjustable load frequency response model, and a frequency dynamic model; The calculation module is used to calculate the frequency response performance ratio of the adjustable load when the system frequency decreases or increases.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

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