Voltage active and reactive dynamic cooperative control method considering communication quality

Abstract

The invention discloses a voltage active and reactive dynamic cooperative control method considering communication quality. The method comprises the following steps: establishing a voltage reactive power dynamic cooperative control model, obtaining reactive power compensation amount of each node photovoltaic inverter in real time under the condition of considering communication network time delay and packet loss, and performing voltage reactive power dynamic cooperative control on a power distribution system; establishing a voltage active power dynamic cooperative control model, when the voltage reactive power dynamic cooperative control does not relieve the overvoltage condition of the power distribution system, obtaining the electric vehicle charging power increment of each node in real time under the condition of considering communication network time delay and packet loss, and performing voltage active power dynamic cooperative control on the power distribution system; and when each node of the power distribution system does not detect the overvoltage in the preset time period, performing cooperative control on the real-time voltage of the power distribution system through an active and reactive backoff mechanism. According to the method, optimal control over the inverter and the electric vehicle can be achieved in the environment with poor communication quality, and the voltage out-of-limit risk caused by high-permeability photovoltaic grid connection is avoided.

Description

Technical Field

[0001] The invention relates to a voltage coordinated control method, and to the technical field of stable operation of electric power systems, and in particular to a voltage active and reactive dynamic coordinated control method taking communication quality into account. Background Art

[0002] As large-scale centralized photovoltaic power stations become increasingly saturated, more and more photovoltaic power generation systems are connected to the distribution network in the form of distributed energy. This transformation makes the voltage limit problem caused by photovoltaic penetration in the distribution network particularly prominent. In this regard, distributed small photovoltaic inverters can participate in the voltage control of the distribution network by providing reactive power compensation. These inverters usually achieve efficient voltage reactive power control in a collaborative manner, assuming that the communication system is fully reliable and can cover the entire distribution network.

[0003] However, the effectiveness of the voltage-reactive power control method depends largely on the quality of the communication network. Small photovoltaic inverters are usually connected to wireless communication networks at a low cost, but this inevitably brings about communication delays and data packet loss problems. These problems will make it difficult to quickly transmit the control instructions generated by the voltage-reactive power control method, thereby affecting the algorithm iteration process and limiting the real-time application of the voltage-reactive power control method. In addition, the final control scheme needs to be determined after multiple iterations. Considering the rapid fluctuations of photovoltaic power generation, existing control instructions are often difficult to keep up with the changes in real-time power.

[0004] At the same time, with the gradual increase in photovoltaic penetration, traditional voltage and reactive power control methods can no longer completely solve the overvoltage problem of distribution networks. The limitation of reactive power compensation capacity of photovoltaic inverters makes it very easy to oversaturate when applied to voltage control of distribution networks with high photovoltaic penetration, thus failing to provide a large amount of reactive power support. Therefore, it is urgent to model the impact of communication network quality and rapid fluctuations in photovoltaic power on distributed control algorithms, and to develop real-time voltage coordinated control methods including active power regulation to deal with potential voltage over-limit risks. Summary of the invention

[0005] In order to solve the problems existing in the background technology, the present invention provides a method for dynamic coordinated control of voltage and active and reactive power taking into account the communication quality. The method solves the technical problem of real-time coordinated voltage control of photovoltaic inverters and electric vehicles in an environment with poor communication quality when a small photovoltaic power generation system with high penetration rate is connected to the power distribution system, and provides technical support for the distributed grid connection of large-scale small photovoltaic power generation systems.

[0006] The technical solution adopted by the present invention is:

[0007] The voltage active and reactive dynamic coordinated control method taking into account communication quality of the present invention comprises:

[0008] S1: Based on the dynamic consistency algorithm, asynchronous event triggering mechanism and information accumulation transmission mechanism, a voltage-reactive dynamic collaborative control model of the distribution system combining local reactive power control and multi-inverter reactive power dynamic control is established. The voltage of each node in the distribution system is input into the voltage-reactive dynamic collaborative control model in real time. After processing, the voltage-reactive dynamic collaborative control model outputs the reactive compensation amount of the photovoltaic inverter at each node in real time as the control instruction considering the communication network delay and packet loss, so as to respond to the rapid fluctuation of photovoltaic power and solve the problem that the algorithm control performance is difficult to meet expectations in an environment with poor communication quality, thereby performing voltage-reactive dynamic collaborative control of the distribution system.

[0009] S2: A voltage active dynamic collaborative control model of the distribution system that combines local active power control with electric vehicle cluster active power dynamic control is established. When the voltage reactive dynamic collaborative control fails to alleviate the overvoltage situation of the distribution system, the voltage of each node in the distribution system after the voltage reactive dynamic collaborative control is input into the voltage active dynamic collaborative control model in real time. After processing by the voltage active dynamic collaborative control model, the real-time output of the charging power increment of the electric vehicle at each node considering the communication network delay and packet loss is used as the control instruction to further suppress the voltage over-limit problem, thereby performing voltage active dynamic collaborative control on the distribution system.

[0010] S3: When no overvoltage is detected at each node of the distribution system within a preset time period, the real-time voltage of the distribution system is collaboratively controlled through the active and reactive power fallback mechanism to achieve dynamic collaborative control of the voltage, active and reactive power of the distribution system.

[0011] In step S1, the voltage-reactive dynamic coordinated control model of the power distribution system is as follows:

[0012]

[0013]

[0014] in, represents the change in local reactive power control of node i in the power distribution system at time t; a represents the control step of local reactive power control; C pv,i represents the total installed capacity of all PV inverters at node i; V i (t) represents the local node voltage of node i at time t; Indicates the preset voltage upper limit; and They represent the local reactive power output of all PV inverters at node i at time t and t+Δt under local reactive power control, Δt represents the time interval of local reactive power control, represents the change in local reactive power output power of all PV inverters at node i at time t under local reactive power control; x pv,i(t) and x pv,i (t+ΔT) represents the reactive consistency variable z of node i at time t and t+ΔT respectively. pv,i (t) The first auxiliary variable, y pv,i (t) and y pv,i (t+ΔT) represents the reactive consistency variable z of node i at time t and t+ΔT respectively. pv,i (t) The second auxiliary variable, whose initial value is x pv,j (0) and y pv,j (0) are respectively set to the reactive compensation amount and the total installed capacity of the node i inverter at the start time of the multi-inverter reactive dynamic control, and ΔT represents the time interval of the multi-inverter reactive dynamic control; and They represent the out-degree of node i and node j, that is, the number of communication links with node i and node j as the head-end nodes; and They represent the first auxiliary variable x received by node i at time t and t-ΔT respectively. pv,i (t) Related coordinated reactive power state value The accumulated value of and Respectively represent the second auxiliary variable y received by node i at time t and t-ΔT pv,i (t) Related coordinated reactive power state value The accumulated value of and Respectively indicate that node j has received the coordinated reactive power state value of node i and The sum of and Update later;[] new Indicates the effective information of reactive state update extracted according to the information accumulation transmission mechanism, and represents the effective information extracted for updating the reactive state of node j according to the information accumulation transmission mechanism; condition 1 is that node i receives a message from its neighboring node j, the time interval between node i receiving a message from neighboring node j this time and last time is recorded as n, and the set of neighboring nodes in condition 1 is recorded as Condition 2 is that node i does not receive any message from its neighboring node j within m consecutive time intervals. The set of neighboring nodes in condition 2 is denoted as l i , once at least one trigger condition is met, the multi-inverter reactive power dynamic control will perform reactive power state update based on the dynamic consistency algorithm, and the node i control will be triggered under condition 1 or condition 2, and n <m;z pv,i (t+ΔT) represents the reactive consistency variable of node i at time t+ΔT; and They represent the reactive output power of all PV inverters at node i at time t and t+ΔT under multi-inverter reactive dynamic control, It represents the change of reactive output power of all PV inverters at node i at time t+ΔT under dynamic reactive control of multiple inverters; Q pv,i (t+ΔT) and Q pv,i (t+ΔT-Δt) represents the reactive compensation amount of the photovoltaic inverter of each node at node i at time t+ΔT and t+ΔT-Δt, respectively, considering the communication network delay and packet loss.

[0015] In step S2, the voltage-active power dynamic coordinated control model of the power distribution system is specifically as follows:

[0016]

[0017]

[0018] in, represents the change in local active power control of node i in the power distribution system at time t; b represents the control step length of local active power control; C ev,i represents the total capacity of the energy storage batteries of all electric vehicles at node i; V i (t)′ represents the local node voltage of node i at time t after voltage-reactive dynamic coordinated control; Indicates the preset voltage upper limit; and They represent the charging power increments of all electric vehicles at node i at time t and t+Δt′ under local active power control respectively; Δt′ represents the time interval of local active power control; represents the change in the charging power increment of all electric vehicles at node i at time t under local active power control; x ev,i (t) and x ev,i (t+ΔT′) represents the active consistency variable z of node i at time t and t+ΔT′ respectively. ev,i (t) The first auxiliary variable, y ev,i (t) and y ev,i (t+ΔT′) represents the active consistency variable z of node i at time t and t+ΔT′ respectively. ev,i (t) The second auxiliary variable, whose initial value is x ev,i (0) and y ev,i (0) are respectively set to the charging power increment and total capacity of the energy storage battery of the electric vehicle at the start time of the active power dynamic control of the electric vehicle cluster, and ΔT′ represents the time interval of the active power dynamic control of the electric vehicle cluster; and They represent the out-degree of node i and node j, that is, the number of communication links with node i and node j as the head-end nodes; and They represent the first auxiliary variable x received by node i at time t and t-ΔT′ respectively. ev,i (t) Related coordinated active power status value The accumulated value of and Respectively represent the second auxiliary variable y received by node i at time t and t-ΔT ev,i (t) Related coordinated active power status value The cumulative value of and Its initial value is set to 0, that is and and They respectively indicate that node j has received the coordinated active power state value of node i and The sum of and Update later;[] new Indicates the effective information of active state update extracted according to the information accumulation transmission mechanism, and represents the effective information extracted according to the information accumulation transmission mechanism for updating the active state of node j; ev,i (t+Δt′) represents the active consistency variable of node i at time t+ΔT′; and They represent the charging power increment of the electric vehicle cluster at node i at time t and t+ΔT′ under the dynamic control of the active power of the electric vehicle cluster, represents the change in the charging power increment of the electric vehicle cluster at node i at time t+ΔT′ under the dynamic control of the active power of the electric vehicle cluster; P ev,i (t+ΔT′) and P ev,i (t+ΔT′-Δt′) represents the charging power increment of electric vehicles at each node at time t+ΔT′ and t+ΔT′-Δt′, respectively, considering the communication network delay and packet loss of node i.

[0019] In the step S3, when no overvoltage is detected at each node of the distribution system within a preset time period, the active power fallback mechanism is first triggered, and the active power consistency variable in the voltage-active power dynamic collaborative control model gradually decreases until it reaches zero. After that, if no overvoltage is detected at each node, the reactive power fallback mechanism is triggered, and the reactive power consistency variable in the voltage-reactive power dynamic collaborative control model gradually decreases until it reaches zero, thereby reducing the burden of reactive power compensation of the photovoltaic inverter and active power adjustment of the electric vehicle, and realizing real-time voltage collaborative control of the distribution system.

[0020] In order to avoid unnecessary reactive power compensation of photovoltaic inverters and charging power adjustment of electric vehicles, this method configures an active power fallback mechanism and a reactive power fallback mechanism for the voltage-reactive power dynamic coordinated control model and the voltage-active power dynamic coordinated control model accordingly.

[0021] The active power fallback mechanism is as follows:

[0022] When the values ​​of the reactive power consistency variables of all nodes in the voltage-reactive power dynamic coordinated control model in the distribution system do not change within the preset time period qΔT′, such as 10ΔT, the local controller does not detect the local overvoltage within the preset time period, that is, Then the active consistency variable in the voltage-active dynamic coordinated control model is reduced by a preset ratio until it reaches zero. At this time, the incremental update of the electric vehicle charging power is as follows:

[0023] z ev，i (t+qΔT′)=z ev，i (t+(q-1)ΔT′)-α′z ev，i (t+(q-1)ΔT′)

[0024] z ev，i (t+(q-1)ΔT′)=z ev，i (t+(q-2)ΔT′)=z ev,i (t+(q-3)ΔT′)=…

[0025] =z ev,i (t+ΔT′)=z ev,i (t)

[0026]

[0027] Among them, z ev，i (t+qΔT′), z ev，i (t+(q-1)ΔT′), z ev，i (t+(q-2)ΔT′), z ev，i (t+(q-3)ΔT′),…,z ev，i (t+ΔT′) and z ev，i (t) represents the active consistency variable of node i at time t+qΔT′, t+(q-1)ΔT′, t+(q-2)ΔT′, t+(q-3)ΔT′, …, t+ΔT′ and t in the voltage-active dynamic coordinated control model, ΔT′ represents the time interval of the active dynamic control of the electric vehicle cluster; α represents the control step size of the active fallback mechanism; represents the charging power increment of all electric vehicles at node i at time t under local active power control, P ev，i(t+qΔT′) represents the charging power increment of each node electric vehicle that is finally outputted by node i at time t+qΔT′, taking into account the communication network delay and packet loss; C ev，i Represents the total capacity of the energy storage batteries of all electric vehicles at node i.

[0028] The reactive power fallback mechanism is as follows:

[0029] When the charging power of the electric vehicle does not need to be adjusted, that is, the active consistency variable in the voltage-active dynamic cooperative control model is zero, if the local controller does not detect local overvoltage within the preset time period, the reactive consistency variable in the voltage-reactive dynamic cooperative control model will be reduced by a preset ratio until it reaches zero. At this time, the reactive compensation amount of the photovoltaic inverter is updated as follows:

[0030] z pv，i (t+qΔT)=z pv，i (t+(q-1)ΔT)-αz pv，i (t+(q-1)ΔT)

[0031] z pv，i (t+(q-1)ΔT)=z pv，i (t+(q-2)ΔT)=z pv，i (t+(q-3)ΔT)=…

[0032] =z pv，i (t+ΔT)=z pv，i (t) and z ev,i (t) = 0

[0033]

[0034] Among them, z pv，i (t+qΔT), z pv，i (t+(q-1)ΔT), z pv，i (t+(q-2)ΔT), z pv，i (t+(q-3)ΔT),…,z pv，i (t+ΔT) and z pv，i (t) represents the reactive consistency variable of node i at time t+ΔT, t+(q-1)ΔT, t+(q-2)ΔT, t+(q-3)ΔT, …, t+ΔT and t in the voltage-reactive dynamic coordinated control model; α represents the control step size of the reactive fallback mechanism; represents the local reactive power output of all PV inverters at node i at time t under local reactive power control, Q pv，i (t+qΔT) represents the reactive power compensation of the photovoltaic inverter of each node at the final output of node i at time t+qΔT, taking into account the communication network delay and packet loss; C pv，iRepresents the total installed capacity of all PV inverters at node i.

[0035] The electronic device of the present invention comprises: a memory and a processor coupled to each other, wherein the memory stores program data, and the processor calls the program data to execute the method as described above.

[0036] The computer-readable storage medium of the present invention stores program data thereon, and is characterized in that the program data implements the method described above when executed by a processor.

[0037] The method of the present invention proposes a real-time voltage cooperative control strategy combining voltage-reactive dynamic cooperative control and voltage-active dynamic cooperative control based on a dynamic consistency algorithm, taking into account the communication quality. By continuously inputting the local reactive output power and active output power of the photovoltaic inverter in each iteration process, the online application of the voltage cooperative control method is realized in the form of dynamic update. In order to weaken the adverse effects of communication delay and data packet loss on the algorithm control performance, the present invention designs an asynchronous event triggering mechanism considering communication delay and an information accumulation transmission mechanism considering data packet loss, thereby solving the problems of overvoltage and reactive power oversaturation of downstream inverters that are prone to occur in distribution systems containing high penetration photovoltaics, and realizing real-time cooperative control of the distribution system voltage.

[0038] The beneficial effects of the present invention are:

[0039] 1) The present invention takes into account that photovoltaic power may fluctuate rapidly during the algorithm iteration process. Based on the dynamic consistency algorithm, the present invention establishes a voltage-reactive dynamic collaborative control model that combines local reactive power control with multi-inverter reactive power dynamic control. By inputting the voltage of each node in real time, the model can output the reactive compensation amount in real time in the form of dynamic updates during each iteration process, thereby improving the algorithm's real-time response capability to rapid fluctuations in photovoltaic power.

[0040] 2) The present invention constructs a voltage-active dynamic collaborative control model. When the overvoltage of the distribution system cannot be completely alleviated by relying solely on the voltage-reactive dynamic collaborative control, the voltage collaborative control technology is supplemented in active power regulation by adjusting the charging power of electric vehicles, thereby fully mobilizing the dispatchable resources of the entire network to ensure the voltage safety and stability of the distribution system.

[0041] 3) The present invention designs an asynchronous event trigger mechanism to address the communication delay problem that is bound to exist in the information transmission process of the algorithm, and designs an information accumulation transmission mechanism to address the possible data packet loss problem. By setting two types of trigger events and adopting the method of accumulating and transmitting information, the efficiency of algorithm communication is greatly enhanced, and the robustness and convergence speed of the algorithm in dealing with environments with poor communication quality are improved.

[0042] 4) An active and reactive power fallback mechanism based on consistency variables is provided, thereby reducing the burden of reactive power compensation of photovoltaic inverters and active power adjustment of electric vehicles under the premise of voltage safety in the distribution network, and improving the efficiency of photovoltaic inverters and electric vehicles in participating in voltage control of the distribution network.

[0043] The present invention effectively improves the robustness and tracking capability of the voltage cooperative control algorithm when dealing with environments with poor communication quality, realizes the real-time application of the voltage cooperative control method, and can achieve optimal control of photovoltaic inverters and electric vehicles under the premise of avoiding voltage exceeding the limit of distribution system nodes due to grid connection of high-penetration photovoltaic power generation systems, so as to promote large-scale grid connection of photovoltaic power generation resources under the background of new power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a flow chart of the method of the present invention;

[0045] Figure 2 is a diagram of an IEEE 33-node power distribution system according to an exemplary embodiment;

[0046] Figure 3 is a distribution network voltage and reactive power coordinated control curve diagram based on a static consistency algorithm according to an exemplary embodiment, wherein: Figure 3 (a) is the voltage amplitude curve based on the static consistency algorithm. Figure 3 (b) is the reactive output curve diagram based on the static consistency algorithm;

[0047] Figure 4 is a distribution network voltage and reactive power coordinated control curve diagram based on a dynamic consistency algorithm according to an exemplary embodiment, wherein: Figure 4 (a) is a voltage amplitude curve based on the dynamic consistency algorithm. Figure 4 (b) is the reactive output curve diagram based on the dynamic consistency algorithm;

[0048] Figure 5 is a voltage amplitude comparison curve diagram under different methods according to an exemplary embodiment;

[0049] Figure 6 is a reactive output comparison curve diagram under different methods according to an exemplary embodiment;

[0050] Figure 7 is a graph of electric vehicle charging power increment according to method 3 shown in accordance with an exemplary embodiment. DETAILED DESCRIPTION

[0051] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0052] like Figure 1 As shown, the method of the present invention is to solve the technical problem of real-time voltage coordinated control of photovoltaic inverters and electric vehicles in an environment with poor communication quality when a high-penetration small-scale photovoltaic power generation system is connected to a power distribution system. The method includes the following steps:

[0053] S1: Based on the dynamic consistency algorithm, asynchronous event triggering mechanism and information accumulation transmission mechanism, a voltage-reactive dynamic collaborative control model of the distribution system combining local reactive power control and multi-inverter reactive power dynamic control is established. The voltage of each node in the distribution system is input into the voltage-reactive dynamic collaborative control model in real time. After processing, the voltage-reactive dynamic collaborative control model outputs the reactive compensation amount of the photovoltaic inverter at each node in real time as the control instruction considering the communication network delay and packet loss, so as to respond to the rapid fluctuation of photovoltaic power and solve the problem that the algorithm control performance is difficult to meet expectations in an environment with poor communication quality, thereby performing voltage-reactive dynamic collaborative control of the distribution system.

[0054] The voltage-reactive dynamic coordinated control model of the distribution system is as follows:

[0055]

[0056] in, represents the change in local reactive power control of node i in the power distribution system at time t; a represents the control step of local reactive power control; C pv,i represents the total installed capacity of all PV inverters at node i; V i (t) represents the local node voltage of node i at time t; Indicates the preset voltage upper limit; and They represent the local reactive power output of all PV inverters at node i at time t and t+Δt under local reactive power control, Δt represents the time interval of local reactive power control, represents the change in local reactive power output power of all PV inverters at node i at time t under local reactive power control; x pv,i (t) and x pv,i (t+ΔT) represents the reactive consistency variable z of node i at time t and t+ΔT respectively. pv,i (t) The first auxiliary variable, y pv,i (t) and y pv,i (t+ΔT) represents the reactive consistency variable z of node i at time t and t+ΔT respectively. pv,i (t) The second auxiliary variable, whose initial value is x pv,j (0) and y pv,j (0) are respectively set to the reactive compensation amount and the total installed capacity of the node i inverter at the start time of the multi-inverter reactive dynamic control, and ΔT represents the time interval of the multi-inverter reactive dynamic control; and They represent the out-degree of node i and node j, that is, the number of communication links with node i and node j as the head-end nodes; and They represent the first auxiliary variable x received by node i at time t and t-ΔT respectively. pv,i (t) Related coordinated reactive power state value The accumulated value of and Respectively represent the second auxiliary variable y received by node i at time t and t-ΔT pv,i (t) Related coordinated reactive power state value The accumulated value of and Respectively indicate that node j has received the coordinated reactive power state value of node i and The sum of and Update later;[] new Indicates the effective information of reactive state update extracted according to the information accumulation transmission mechanism, and represents the effective information extracted for updating the reactive state of node j according to the information accumulation transmission mechanism; condition 1 is that node i receives a message from its neighboring node j, the time interval between node i receiving a message from neighboring node j this time and last time is recorded as n, and the set of neighboring nodes in condition 1 is recorded as Condition 2 is that node i does not receive any message from its neighboring node j within m consecutive time intervals. The set of neighboring nodes in condition 2 is denoted as l i , once at least one trigger condition is met, the multi-inverter reactive power dynamic control will perform reactive power state update based on the dynamic consistency algorithm, and the node i control will be triggered under condition 1 or condition 2, and n <m;z pv,i (t+ΔT) represents the reactive consistency variable of node i at time t+ΔT; and They represent the reactive output power of all PV inverters at node i at time t and t+ΔT under multi-inverter reactive dynamic control, It represents the change of reactive output power of all PV inverters at node i at time t+ΔT under dynamic reactive control of multiple inverters; Q pv,i (t+ΔT) and Q pv,i (t+ΔT-Δt) represents the reactive compensation amount of the photovoltaic inverter of each node at node i at time t+ΔT and t+ΔT-Δt, respectively, considering the communication network delay and packet loss.

[0057] The voltage-reactive dynamic coordinated control model includes local reactive power control and multi-inverter reactive power dynamic control, as follows:

[0058] 1) Local reactive power control:

[0059] The local controller monitors the local node voltage of the distribution system in real time. If the local node voltage exceeds the voltage upper limit defined by the grid dispatcher, the photovoltaic inverter absorbs a certain amount of reactive power in proportion to the voltage exceeding the limit to alleviate the local overvoltage of the distribution system.

[0060] 2) Dynamic reactive power control of multiple inverters based on dynamic consistency algorithm:

[0061] In order to avoid reactive power oversaturation of photovoltaic inverters at the end of the feeder of a distribution system with high penetration of photovoltaics, photovoltaic inverters need to continuously provide reactive compensation. At the same time, considering the rapid fluctuation characteristics of photovoltaic power, the reactive compensation required to alleviate overvoltage on photovoltaic inverters is usually time-varying. In this regard, the dynamic control of multi-inverter reactive power adopts a dynamic consistency algorithm. By continuously inputting the local reactive output power of the photovoltaic inverter, it transmits collaborative state information to neighboring nodes at regular intervals in the form of dynamic updates and redistributes the reactive compensation of all inverters in proportion to respond to the rapid fluctuations of photovoltaic power. However, since communication network congestion may cause the loss of data packets carrying collaborative state information, this method designs an information accumulation transmission mechanism. In addition, the time required for information transmission between nodes in the distribution system is usually not constant, that is, information sent at the same time will be received at different times. In order to deal with the asynchronous characteristics of this information transmission, the present invention designs an asynchronous event triggering mechanism to perform local state updates. The information accumulation transmission mechanism and the asynchronous event triggering mechanism are designed as follows:

[0062] a) Information accumulation transmission mechanism:

[0063] The coordinated reactive power state information that needs to be transmitted to the neighboring nodes for the dynamic reactive power control of multiple inverters is: and The information accumulation transmission mechanism designed by the method accumulates the value of the collaborative state information before transmitting the data packet, thereby eliminating the steady-state convergence error of the multi-inverter reactive dynamic control caused by random packet loss in an environment with poor communication quality.

[0064] The information accumulation transmission mechanism designed by the present invention uses the accumulation value in the data packet. and Replace the coordinated reactive power state value and It is transmitted and broadcast to other neighboring nodes through the communication link. It is worth noting that the coordinated reactive power state value and are transmitted in the same data packet, so they will be received, lost or delayed at the same time. In addition, the information accumulation transmission mechanism designed by the present invention requires that the sending node i needs to carry the timestamp of the sending time when transmitting information, and the receiving node j determines whether the received data packet is the latest one by the timestamp when receiving information. If the timestamp of the received data packet is older than the existing data packet (that is, the sending time of the received data packet is later than the sending time of the existing received data packet), the data packet will be deemed invalid. If the timestamp of the received data packet is newer than the existing data packets, the received data packet (including and ) extracts valid information for reactive power status update.

[0065] It is worth noting that due to the existence of time delay and data packet loss, the timestamp sequence of the data packets received by the receiving node may not be continuous. In this case, according to the information accumulation transmission mechanism designed by the present invention, the lost collaborative status message can always be numerically compensated by its subsequently transmitted data packets.

[0066] b) Asynchronous event triggering mechanism:

[0067] The asynchronous event trigger mechanism designed by the present invention triggers each node independently under the following two conditions: Condition 1) Node i receives a message from its neighboring node j, and the time interval between node i receiving a message from neighboring node j this time and the last time is recorded as n, and the set of neighboring nodes in condition 1 is recorded as Condition 2) Node i does not receive any message from its neighboring node j within m consecutive time intervals. The set of neighboring nodes in condition 2 is denoted as l i Once at least one trigger condition is met, the multi-inverter reactive power dynamic control will perform reactive power state update based on the dynamic consistency algorithm. After node i performs reactive power state update, the coordinated reactive power state value and It will be accumulated through the information accumulation transmission mechanism and broadcast to other neighboring nodes through the communication link.

[0068] The multi-inverter reactive power dynamic control of PV inverters is a simple algebraic operation, and its control goal is to achieve fair reactive output power redistribution among all PV inverters, that is:

[0069]

[0070] in, Represents the total amount of local reactive power compensation for all nodes at time t Total installed capacity of all inverters The ratio of ; I represents the total number of nodes with PV inverters in the distribution system.

[0071] The time scale of local reactive power control Δt is usually in milliseconds, while the time scale of multi-inverter reactive power dynamic control ΔT is usually in seconds. Local reactive power control The reactive power compensation of photovoltaic inverters at each node is finally output by the voltage-reactive power dynamic coordinated control model, which is accumulated at different control time scales.

[0072] S2: A voltage active dynamic collaborative control model of the distribution system that combines local active power control with electric vehicle cluster active power dynamic control is established. When the voltage reactive dynamic collaborative control fails to alleviate the overvoltage situation of the distribution system, the voltage of each node in the distribution system after the voltage reactive dynamic collaborative control is input into the voltage active dynamic collaborative control model in real time. After processing by the voltage active dynamic collaborative control model, the real-time output of the charging power increment of the electric vehicle at each node considering the communication network delay and packet loss is used as the control instruction to further suppress the voltage over-limit problem, thereby performing voltage active dynamic collaborative control on the distribution system.

[0073] The voltage and active power dynamic coordinated control model of the distribution system is as follows:

[0074]

[0075]

[0076] in, represents the change in local active power control of node i in the power distribution system at time t; b represents the control step length of local active power control; C ev,i represents the total capacity of the energy storage batteries of all electric vehicles at node i; V i (t)′ represents the local node voltage of node i at time t after voltage-reactive dynamic coordinated control; Indicates the preset voltage upper limit; and They represent the charging power increments of all electric vehicles at node i at time t and t+Δt′ under local active power control respectively; Δt′ represents the time interval of local active power control; represents the change in the charging power increment of all electric vehicles at node i at time t under local active power control; x ev,i (t) and x ev,i (t+ΔT′) represents the active consistency variable z of node i at time t and t+ΔT′ respectively. ev,i (t) The first auxiliary variable, y ev,i (t) and y ev,i (t+ΔT′) represents the active consistency variable z of node i at time t and t+ΔT′ respectively.ev,i (t) The second auxiliary variable, whose initial value is x ev,i (0) and y ev,i (0) are respectively set to the charging power increment and total capacity of the energy storage battery of the electric vehicle at the start time of the active power dynamic control of the electric vehicle cluster, and ΔT′ represents the time interval of the active power dynamic control of the electric vehicle cluster; and They represent the out-degree of node i and node j, that is, the number of communication links with node i and node j as the head-end nodes; and They represent the first auxiliary variable x received by node i at time t and t-ΔT′ respectively. ev,i (t) Related coordinated active power status value The accumulated value of and Respectively represent the second auxiliary variable y received by node i at time t and t-ΔT ev,i (t) Related coordinated active power status value The cumulative value of and Its initial value is set to 0, that is and and They respectively indicate that node j has received the coordinated active power state value of node i and The sum of and Update later;[] new Indicates the effective information of active state update extracted according to the information accumulation transmission mechanism, and represents the effective information extracted according to the information accumulation transmission mechanism for updating the active state of node j; ev,i (t+ΔT′) represents the active consistency variable of node i at time t+ΔT′; and They represent the charging power increment of the electric vehicle cluster at node i at time t and t+ΔT′ under the dynamic control of the active power of the electric vehicle cluster, represents the change in the charging power increment of the electric vehicle cluster at node i at time t+ΔT′ under the dynamic control of the active power of the electric vehicle cluster; P ev,i (t+ΔT′) and P ev,i (t+ΔT′-Δt′) represents the charging power increment of electric vehicles at each node at time t+ΔT′ and t+ΔT′-Δt′, respectively, considering the communication network delay and packet loss of node i.

[0077] The voltage-active dynamic coordinated control model includes local active power control and electric vehicle cluster active power dynamic control, as follows:

[0078] When the photovoltaic penetration rate of the distribution system is high, the voltage-active dynamic coordinated control relying solely on the photovoltaic inverter may not be able to completely suppress the system overvoltage. In this case, it is necessary to further utilize active power regulation, such as energy storage battery (such as electric vehicle) charging power control. The present invention takes the charging power regulation of electric vehicles as an example to illustrate the voltage-active dynamic coordinated control model. Similar to the local reactive power control and multi-inverter reactive power dynamic control in step S1, the voltage-active dynamic coordinated control model is mainly divided into two steps: local active power control and electric vehicle cluster active power dynamic control:

[0079] 1) Local active power control:

[0080] Voltage-reactive dynamic coordinated control is used to alleviate overvoltage in the distribution system. When the reactive consistency variable of the PV inverter exceeds the defined threshold, i.e., z pv,i >z pv,max At this time, the reactive power compensation of the photovoltaic inverter tends to be saturated. If the local controller still detects local overvoltage, the electric vehicle will increase the charging power by a certain amount according to the proportion of the voltage exceeding the limit to alleviate the local overvoltage of the distribution system.

[0081] 2) Dynamic control of active power of electric vehicle clusters based on dynamic consensus algorithm:

[0082] Dynamic control of active power of electric vehicle cluster using accumulated value in data packet and Replace the coordinated active power status value and Transmit and broadcast to other neighboring nodes through the communication link The receiving node j selects the latest received data packet (including and ) Extract valid information for active status update and

[0083] On this basis, once at least one trigger condition is met (the trigger condition is consistent with the multi-inverter reactive power dynamic control), the active power dynamic control of the electric vehicle cluster will redistribute the increment of charging power of all electric vehicles in proportion at regular intervals in the form of dynamic updates based on the dynamic consistency algorithm. After node i executes the active power state update, the coordinated active power state value and It will be accumulated through the information accumulation transmission mechanism and broadcast to other neighboring nodes through the communication link.

[0084] The control goal of the active power dynamic control of electric vehicle clusters is to achieve fair redistribution of charging power increments among all electric vehicles, namely:

[0085]

[0086] in, is the charging power increment of all nodes of electric vehicles at time t Total capacity of all electric vehicle storage batteries ratio.

[0087] Through the dynamic control of the active power of electric vehicle cluster Local active power control The addition is performed at different control time scales to jointly constitute the charging power increment of the electric vehicles at each node that is ultimately output by the voltage-active power dynamic coordinated control model.

[0088] S3: When no overvoltage is detected at each node of the distribution system within a preset time period, the real-time voltage of the distribution system is collaboratively controlled through the active and reactive power fallback mechanism to achieve dynamic collaborative control of the voltage, active and reactive power of the distribution system.

[0089] When no overvoltage is detected at each node of the distribution system within a preset time period, the active power fallback mechanism is triggered first, and the active power consistency variable in the voltage-active power dynamic collaborative control model gradually decreases until it reaches zero. After that, if no overvoltage is detected at each node, the reactive power fallback mechanism is triggered, and the reactive power consistency variable in the voltage-reactive power dynamic collaborative control model gradually decreases until it reaches zero, thereby reducing the burden of reactive power compensation of photovoltaic inverters and active power adjustment of electric vehicles, and realizing real-time voltage collaborative control of the distribution system.

[0090] In order to avoid unnecessary reactive power compensation of photovoltaic inverters and charging power adjustment of electric vehicles, this method configures an active power fallback mechanism and a reactive power fallback mechanism for the voltage-reactive power dynamic coordinated control model and the voltage-active power dynamic coordinated control model accordingly.

[0091] The active power fallback mechanism is as follows:

[0092] When the values ​​of the reactive power consistency variables of all nodes in the voltage-reactive power dynamic coordinated control model in the distribution system do not change within the preset time period qΔT′, such as 10ΔT, the local controller does not detect the local overvoltage within the preset time period, that is, Then the active consistency variable in the voltage-active dynamic coordinated control model is reduced by a preset ratio until it reaches zero. At this time, the incremental update of the electric vehicle charging power is as follows:

[0093] z ev,i (t+qΔT′)=zev,i (t+(q-1)ΔT′)-α′z ev,i (t+(q-1)ΔT′)

[0094] z ev,i (t+(q-1)ΔT′)=z ev,i (t+(q-2)ΔT′)=z ev,i (t+(q-3)ΔT′)=…

[0095] =z ev,i (t+ΔT′)=z ev,i (t)

[0096]

[0097] Among them, z ev,i (t+qΔT′), z ev,i (t+(q-1)ΔT′), z ev,i (t+(q-2)ΔT′), z ev,i (t+(q-3)ΔT′),…,z ev,i (t+ΔT′) and z ev,i (t) represents the active consistency variable of node i at time t+qΔT′, t+(q-1)ΔT′, t+(q-2)ΔT′, t+(q-3)ΔT′, …, t+ΔT′ and t in the voltage-active dynamic coordinated control model, ΔT′ represents the time interval of the active dynamic control of the electric vehicle cluster; α represents the control step size of the active fallback mechanism; represents the charging power increment of all electric vehicles at node i at time t under local active power control, P ev，i (t+qΔT′) represents the charging power increment of each node electric vehicle that is finally outputted by node i at time t+qΔT′, taking into account the communication network delay and packet loss; C ev，i Represents the total capacity of the energy storage batteries of all electric vehicles at node i.

[0098] The reactive power fallback mechanism is as follows:

[0099] When the charging power of the electric vehicle does not need to be adjusted, that is, the active consistency variable in the voltage-active dynamic cooperative control model is zero, if the local controller does not detect local overvoltage within the preset time period, the reactive consistency variable in the voltage-reactive dynamic cooperative control model will be reduced by a preset ratio until it reaches zero. At this time, the reactive compensation amount of the photovoltaic inverter is updated as follows:

[0100] z pv，i (t+qΔT)=z pv，i (t+(q-1)ΔT)-αz pv，i (t+(q-1)ΔT)

[0101] z pv，i (t+(q-1)ΔT)=z pv，i (t+(q-2)ΔT)=z pv，i (t+(q-3)ΔT)=…

[0102] =z pv，i (t+ΔT)=z pv，i (t) and z ev,i (t) = 0

[0103]

[0104] Among them, z pv，i (t+qΔT), z pv，i (t+(q-1)ΔT), z pv，i (t+(q-2)ΔT), z pv，i (t+(q-3)ΔT),…,z pv，i (t+ΔT) and z pv，i (t) represents the reactive consistency variable of node i at time t+ΔT, t+(q-1)ΔT, t+(q-2)ΔT, t+(q-3)ΔT, …, t+ΔT and t in the voltage-reactive dynamic coordinated control model; α represents the control step size of the reactive fallback mechanism; represents the local reactive power output of all PV inverters at node i at time t under local reactive power control, Q pv，i (t+qΔT) represents the reactive power compensation of the photovoltaic inverter of each node at the final output of node i at time t+qΔT, taking into account the communication network delay and packet loss; C pv，i Represents the total installed capacity of all PV inverters at node i.

[0105] In order to further understand the present invention, the present invention selects Figure 2 The IEEE 33-node distribution system shown in the figure is used as a test case. There are two-way communication links between the adjacent nodes of the distribution network, and additional communication links are added to promote algorithm convergence. In the test case, photovoltaic inverters and electric vehicles participate in the voltage control of the distribution network by providing reactive power compensation and increasing charging power. The nodes of photovoltaic inverters and their installed capacity and the nodes of electric vehicles and their energy storage battery capacity are shown in Tables 1 and 2 respectively. For the power network, this example uses the per-unit value of the voltage upper limit defined by the grid dispatcher Set to 1.05pu, its reference voltage is 12.66kV, the control step a of local reactive power control and the control step b of local active power control are both set to 0.5, and the maximum reactive power output of the photovoltaic inverter is set to 0.4583 of its maximum active power. For the communication network, this example sets the maximum communication delay to 2 seconds and the probability of data packet loss to 0.1. The present invention illustrates the superiority of the proposed voltage active and reactive dynamic coordinated control method from the following different aspects.

[0106] Table 1 Installation capacity of photovoltaic inverters at each node

[0107]

[0108] Table 2 Energy storage battery capacity of electric vehicles at each node

[0109]

[0110] 1) Online application performance of real-time voltage coordinated control:

[0111] The present invention uses the static consistency algorithm as a control. In the event of data packet loss, the photovoltaic inverter will reuse the last updated local state value to promote algorithm iteration. The multi-inverter reactive dynamic control based on the static consistency algorithm redistributes the reactive compensation burden among all inverters approximately every 30 seconds. Figure 3 and Figure 4 The voltage and reactive power coordinated control curves of distribution networks based on static consistency algorithm and dynamic consistency algorithm are shown respectively. Figure 3 As shown in (b), if a static consistency algorithm is used, the photovoltaic inverter of the upstream node (such as node 6) can adjust its reactive output power every 30 seconds according to the coordinated reactive status information and participate in the voltage and reactive coordinated control of the distribution network. However, due to the rapid fluctuation of photovoltaic power, this type of static redistribution method cannot effectively track the control target in real time, that is, the average reactive output power of all inverters. As a result, the reactive compensation amount of each node varies greatly, especially the reactive compensation capacity of the downstream node is prone to oversaturation. The reactive compensation capacity of the photovoltaic inverter of the downstream node 18 was oversaturated for the first time at 2 minutes and 29 seconds. After that, if the photovoltaic power continues to increase, the inverter cannot provide further reactive compensation, which eventually leads to the following results. Figure 3The voltage amplitude of node 18 shown in (a) exceeds the upper limit. The method proposed in the present invention uses a dynamic consistency algorithm as a carrier, continuously inputs the local reactive output power of the photovoltaic inverter, transmits the collaborative state information to the neighboring nodes at regular intervals in the form of dynamic updates, and proportionally redistributes the reactive compensation burden of all inverters to respond to the rapid fluctuation of photovoltaic power. Therefore, the reactive compensation burden (reactive compensation amount) of the inverter on the downstream node 18 will quickly spread to the remaining nodes (including node 6) and will be shared by the local reactive control of the remaining nodes, such as Figure 4 Therefore, in this case, the reactive power compensation capacity of the photovoltaic inverter on the downstream node is not easy to saturate, and the voltage amplitude of each node can be well controlled within the allowed range, as shown in (b). Figure 4 As shown in (a).

[0112] 2) The impact of the parameter settings of the asynchronous event trigger mechanism on the communication frequency:

[0113] According to the event trigger mechanism designed by the present invention, if node i does not receive any message from its neighboring node j within m consecutive time intervals, the reactive state update is automatically triggered, and the coordinated reactive state value is accumulated through the information accumulation transmission mechanism and sent to the neighboring node j. Among them, the setting of the value of parameter m in the asynchronous event trigger mechanism will greatly affect the frequency of the communication system. The simulation results of the example show that when the parameter ω is set to 1, 4 and 7, the proposed method only requires 93%, 69% and 52% of the communication frequency compared with the traditional method. Although increasing the parameter ω can effectively reduce the transmission burden of the communication network, a larger ω also means that the local reactive or active change between two iterations of the dynamic consistency algorithm is also increased accordingly, and ultimately the tracking error between the proposed method and the expected target is enlarged.

[0114] 3) Voltage control performance of voltage active and reactive dynamic coordinated control method:

[0115] This section of examples is intended to illustrate the superiority of the voltage active and reactive dynamic coordinated control method proposed in this invention in terms of voltage control performance. Since node 18 is the terminal node of the distribution network, the reactive compensation capacity is very likely to be oversaturated and induce overvoltage risks, so this section of examples takes the control curve of node 18 as the research object. Figure 5 , Figure 6 and Figure 7 The voltage control performance of the distribution network at node 18 was compared under three schemes: no control strategy (denoted as method 1), only voltage and reactive power dynamic coordinated control strategy (denoted as method 2), and real-time voltage coordinated control strategy combining voltage and reactive power dynamic coordinated control with voltage and active power dynamic coordinated control (denoted as method 3).

[0116] like Figure 5As shown in FIG. 1 , since method 1 does not alleviate the system overvoltage by reactive power compensation of photovoltaic inverters or adjustment of electric vehicle charging power, that is, does not apply any voltage control, the voltage amplitude of node 18 will quickly rise to about 1.095 pu. Figure 6 As shown in Figure 2, method 2 can successfully control the voltage within a safe range before the reactive compensation capacity of the photovoltaic inverter is saturated. However, when the reactive compensation capacity is saturated, the photovoltaic inverter cannot completely suppress the system overvoltage. At this time, the photovoltaic power continues to increase and eventually causes the system voltage to rise and exceed 1.06pu. Figure 7 As shown, method 3, i.e., the method proposed in the present invention, adopts a real-time voltage cooperative control strategy that combines voltage-reactive dynamic cooperative control with voltage-active dynamic cooperative control. Voltage-reactive dynamic cooperative control is used to suppress system overvoltage first. When the reactive power compensation of the photovoltaic inverter is about to be saturated, the electric vehicle begins to participate in system voltage control by increasing the charging power. Under the active and reactive dynamic cooperative control of the photovoltaic inverter and the electric vehicle, the method proposed in the present invention can successfully control the voltage of the distribution system within its allowable range.

[0117] Corresponding to the embodiment of the method of the present invention, the present invention also provides an embodiment of a voltage active and reactive dynamic coordinated control device taking into account communication quality, which is specifically as follows:

[0118] The voltage-reactive dynamic collaborative control model establishment unit establishes a voltage-reactive dynamic collaborative control model that combines local reactive power control and multi-inverter reactive power dynamic control based on the dynamic consistency algorithm and the designed asynchronous event triggering mechanism and information accumulation transmission mechanism. The voltage of each node in the distribution system is input into the voltage-reactive dynamic collaborative control model in real time. The voltage-reactive dynamic collaborative control model outputs the reactive compensation amount of the photovoltaic inverter at each node as a control instruction in real time considering the communication network delay and packet loss, so as to respond to the rapid fluctuation of photovoltaic power and solve the problem that the algorithm control performance is difficult to meet expectations under poor communication quality.

[0119] The voltage and active power dynamic collaborative control model establishment unit, if the voltage and reactive power dynamic collaborative control model still cannot effectively alleviate the overvoltage of the distribution system, then a voltage and active power dynamic collaborative control model combining local active power control and electric vehicle cluster active power dynamic control is established, and the voltage of each node in the distribution system after the voltage and reactive power dynamic collaborative control is input into the voltage and active power dynamic collaborative control model in real time. The voltage and active power dynamic collaborative control model then outputs the charging power increment of the electric vehicle at each node as a control instruction in real time considering the communication network delay and packet loss, so as to further suppress the voltage over-limit problem.

[0120] Active power fallback and reactive power fallback execution units, when no overvoltage is detected at each node of the distribution system within a certain period of time, the active power fallback mechanism is first triggered, and the active power consistency variable in the voltage-active power dynamic collaborative control model gradually decreases until it reaches zero. After that, if no overvoltage is detected at each node, the reactive power fallback mechanism is triggered, and the reactive power consistency variable in the voltage-reactive power dynamic collaborative control model gradually decreases until it reaches zero, thereby reducing the burden of reactive power compensation of photovoltaic inverters and active power adjustment of electric vehicles, and realizing real-time voltage collaborative control of the distribution system.

[0121] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0122] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only schematic, in which the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of the present invention. Ordinary technicians in this field can understand and implement it without paying creative work.

[0123] Correspondingly, the present invention also provides an electronic device, comprising: one or more processors; a memory for storing one or more programs; when the one or more programs are executed by one or more processors, the one or more processors implement a method for dynamic coordinated control of voltage active and reactive power taking into account communication quality as described above.

[0124] Accordingly, the present invention also provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implements a method for dynamic coordinated control of voltage active and reactive power taking into account communication quality as described above.

[0125] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the disclosure disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0126] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for dynamic coordinated control of voltage and active and reactive power taking into account communication quality, characterized in that: include: S1: Establish a voltage-reactive dynamic coordinated control model for the distribution system, input the voltage of each node of the distribution system into the voltage-reactive dynamic coordinated control model in real time, and after processing by the voltage-reactive dynamic coordinated control model, output the reactive compensation amount of the photovoltaic inverter of each node in real time as the control instruction in consideration of the communication network delay and packet loss, so as to perform voltage-reactive dynamic coordinated control on the distribution system; S2: Establish a voltage-active dynamic cooperative control model for the distribution system. When the voltage-reactive dynamic cooperative control fails to alleviate the overvoltage of the distribution system, the voltage of each node in the distribution system after the voltage-reactive dynamic cooperative control is input into the voltage-active dynamic cooperative control model in real time. After processing by the voltage-active dynamic cooperative control model, the real-time output of the charging power increment of the electric vehicle at each node considering the communication network delay and packet loss is used as the control instruction, so as to perform voltage-active dynamic cooperative control on the distribution system. S3: When no overvoltage is detected at each node of the distribution system within a preset time period, the real-time voltage of the distribution system is collaboratively controlled through the active and reactive power fallback mechanism to achieve dynamic collaborative control of the voltage, active and reactive power of the distribution system.

2. The voltage active and reactive dynamic coordinated control method taking communication quality into account according to claim 1 is characterized in that: In step S1, the voltage-reactive dynamic coordinated control model of the power distribution system is as follows: in, represents the change in local reactive power control of node i in the power distribution system at time t; a represents the control step of local reactive power control; C pv,i represents the total installed capacity of all PV inverters at node i; V i (t) represents the local node voltage of node i at time t; Indicates the preset voltage upper limit; and They represent the local reactive power output of all PV inverters at node i at time t and t+Δt under local reactive power control, Δt represents the time interval of local reactive power control, represents the change in local reactive power output power of all PV inverters at node i at time t under local reactive power control; x pv,i (t) and x pv,i (t+ΔT) represents the first auxiliary variable of node i at time t and t+ΔT respectively, y pv,i (t) and y pv,i (t+ΔT) represents the second auxiliary variable of node i at time t and t+ΔT respectively, and ΔT represents the time interval of the dynamic reactive power control of the multi-inverter; and Represent the out-degree of node i and node j respectively; and They represent the first auxiliary variable x received by node i at time t and t-ΔT respectively. pv,i (t) Related coordinated reactive power state value The accumulated value of and Respectively represent the second auxiliary variable y received by node i at time t and t-ΔT pv,i (t) Related coordinated reactive power state value The accumulated value of and Respectively indicate that node j has received the coordinated reactive power state value of node i and The sum of; [] new represents the effective information of reactive state update extracted according to the information accumulation transmission mechanism; condition 1 is that node i receives a message from its neighboring node j, the time interval between node i receiving a message from neighboring node j this time and last time is recorded as n, and the set of neighboring nodes in condition 1 is recorded as Condition 2 is that node i does not receive any message from its neighboring node j within m consecutive time intervals. The set of neighboring nodes in condition 2 is denoted as l i , node i control will be triggered under condition 1 or condition 2, and n <m;z pv,i (t+ΔT) represents the reactive consistency variable of node i at time t+ΔT; and They represent the reactive output power of all PV inverters at node i at time t and t+ΔT under multi-inverter reactive dynamic control, It represents the change of reactive output power of all PV inverters at node i at time t+ΔT under dynamic reactive control of multiple inverters; Q pv,i (t+ΔT) and Q pv,i (t+ΔT-Δt) represents the reactive compensation amount of the photovoltaic inverter of each node at node i at time t+ΔT and t+ΔT-Δt, respectively, considering the communication network delay and packet loss.

3. The voltage active and reactive dynamic coordinated control method taking communication quality into account according to claim 2 is characterized in that: In step S2, the voltage-active power dynamic coordinated control model of the power distribution system is specifically as follows: in, represents the change in local active power control of node i in the power distribution system at time t; b represents the control step length of local active power control; C ev,i represents the total capacity of the energy storage batteries of all electric vehicles at node i; V i (t)′ represents the local node voltage of node i at time t after voltage-reactive dynamic coordinated control; Indicates the preset voltage upper limit; and They represent the charging power increments of all electric vehicles at node i at time t and t+Δt′ under local active power control respectively; Δt′ represents the time interval of local active power control; represents the change in the charging power increment of all electric vehicles at node i at time t under local active power control; x ev,i (t) and x ev,i (t+ΔT′) represents the first auxiliary variable of node i at time t and t+ΔT′, respectively, ev,i (t) and y ev,i (t+ΔT′) represents the second auxiliary variable of node i at time t and t+ΔT′, respectively, and ΔT′ represents the time interval of active dynamic control of electric vehicle cluster; and Represent the out-degree of node i and node j respectively; and They represent the first auxiliary variable x received by node i at time t and t-ΔT′ respectively. ev,i (t) Related coordinated active power status value The accumulated value of and Respectively represent the second auxiliary variable y received by node i at time t and t-ΔT ev,i (t) Related coordinated active power status value The accumulated value of and They respectively indicate that node j has received the coordinated active power state value of node i and The sum of; [] new Indicates the effective information of active state update extracted according to the information accumulation transmission mechanism; ev,i (t+ΔT′) represents the active consistency variable of node i at time t+ΔT′; and They represent the charging power increment of the electric vehicle cluster at node i at time t and t+ΔT′ under the dynamic control of the active power of the electric vehicle cluster, represents the change in the charging power increment of the electric vehicle cluster at node i at time t+ΔT′ under the dynamic control of the active power of the electric vehicle cluster; P ev,i (t+ΔT′) and P ev,i (t+ΔT′-Δt′) represents the charging power increment of electric vehicles at each node at time t+ΔT′ and t+ΔT′-Δt′, respectively, considering the communication network delay and packet loss of node i.

4. The voltage active and reactive dynamic coordinated control method taking communication quality into account according to claim 1 is characterized in that: In the step S3, when no overvoltage is detected at each node of the distribution system within a preset time period, the active power fallback mechanism is first triggered, and the active power consistency variable in the voltage-active power dynamic collaborative control model gradually decreases until it reaches zero. After that, if no overvoltage is detected at each node, the reactive power fallback mechanism is triggered, and the reactive power consistency variable in the voltage-reactive power dynamic collaborative control model gradually decreases until it reaches zero, thereby realizing real-time voltage collaborative control of the distribution system.

5. The voltage active and reactive dynamic coordinated control method taking communication quality into account according to claim 4 is characterized in that: The active power fallback mechanism is as follows: When the values ​​of the reactive consistency variables of all nodes in the voltage-reactive dynamic coordinated control model of the distribution system do not change within the preset time period qΔT′, and the local controller does not detect the local overvoltage within the preset time period, the active consistency variable in the voltage-active dynamic coordinated control model is reduced by a preset ratio until it reaches zero. At this time, the electric vehicle charging power increment is updated as follows: Z ev,i (t+qΔT′)=z ev,i (t+(q-1)ΔT′)-α′z ev,i (t+(q-1)ΔT′) z ev,i (t+(q-1)ΔT′)=z ev,i (t+(q-2)ΔT′)=z ev,i (t+(q-3)ΔT′)=… =z ev,i (t+ΔT′)=z ev,i (t) Among them, z ev,i (t+qΔT′), z ev,i (t+(q-1)ΔT′), z ev,i (t+(q-2)ΔT′), z ev,i (t+(q-3)ΔT′),…,z ev,i (t+ΔT′) and z ev,i (t) represents the active consistency variable of node i at time t+qΔT′, t+(q-1)ΔT′, t+(q-2)ΔT′, t+(q-3)ΔT′, …, t+ΔT′ and t in the voltage-active dynamic coordinated control model, ΔT′ represents the time interval of the active dynamic control of the electric vehicle cluster; α′ represents the control step size of the active fallback mechanism; represents the charging power increment of all electric vehicles at node i at time t under local active power control, P ev,i (t+qΔT′) represents the charging power increment of each node electric vehicle that is finally outputted by node i at time t+qΔT′, taking into account the communication network delay and packet loss; C ev,i Represents the total capacity of the energy storage batteries of all electric vehicles at node i.

6. The voltage active and reactive dynamic coordinated control method taking communication quality into account according to claim 4 is characterized in that: The reactive power fallback mechanism is as follows: When the charging power of the electric vehicle does not need to be adjusted, that is, the active consistency variable in the voltage-active dynamic cooperative control model is zero, if the local controller does not detect local overvoltage within the preset time period, the reactive consistency variable in the voltage-reactive dynamic cooperative control model will be reduced by a preset ratio until it reaches zero. At this time, the reactive compensation amount of the photovoltaic inverter is updated as follows: z pv,i (t+qΔT)=z pv,i (t+(q-1)ΔT)-αz pv,i (t+(q-1)ΔT) z pv,i (t+(q-1)ΔT)=z pv,i (t+(q-2)ΔT)=z pv,i (t+(q-3)ΔT)=… = z pv,i (t + ΔT) = z pv,i (t) and z ev,i (t) = 0 Among them, z pv,i (t+qΔT), z pv,i (t+(q-1)ΔT), z pv,i (t+(q-2)ΔT), z pv,i (t+(q-3)ΔT),…,z pv,i (t+ΔT) and z pv,i (t) represents the reactive consistency variable of node i at time t+ΔT, t+(q-1)ΔT, t+(q-2)ΔT, t+(q-3)ΔT, …, t+ΔT and t in the voltage-reactive dynamic coordinated control model; α represents the control step size of the reactive fallback mechanism; represents the local reactive power output of all PV inverters at node i at time t under local reactive power control, Q pv,i (t+qΔT) represents the reactive power compensation of the photovoltaic inverter of each node at the final output of node i at time t+qΔT, taking into account the communication network delay and packet loss; C pv,i Represents the total installed capacity of all PV inverters at node i.

7. An electronic device, characterized in that: include: A memory and a processor coupled to each other, wherein the memory stores program data, and the processor calls the program data to execute the method according to any one of claims 1 to 6.

8. A computer-readable storage medium having program data stored thereon, characterized in that: When the program data is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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