CN110729817A - Power distribution network voltage coordination control system and control method thereof - Google Patents

Power distribution network voltage coordination control system and control method thereof Download PDF

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CN110729817A
CN110729817A CN201911047762.6A CN201911047762A CN110729817A CN 110729817 A CN110729817 A CN 110729817A CN 201911047762 A CN201911047762 A CN 201911047762A CN 110729817 A CN110729817 A CN 110729817A
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voltage
power
bus
network
hybrid
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寇鹏
梁得亮
高荣
柳轶彬
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Xian Jiaotong University
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Xian Jiaotong University
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
    • H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
    • H02J3/16—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by adjustment of reactive power
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/30—Reactive power compensation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/70—Smart grids as climate change mitigation technology in the energy generation sector
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/22—Flexible AC transmission systems [FACTS] or power factor or reactive power compensating or correcting units
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S40/00—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them
    • Y04S40/12—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
    • Y04S40/126—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment using wireless data transmission

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  • Power Engineering (AREA)
  • Remote Monitoring And Control Of Power-Distribution Networks (AREA)

Abstract

A distribution network voltage coordination control system and a control method thereof comprise a distribution network monitoring center, a wireless communication network, nH hybrid distribution transformers and nB buses; the wireless communication network connects each hybrid distribution transformer with the distribution network monitoring center; each hybrid distribution transformer and the monitoring center respectively comprise a wireless transmission module; the power distribution network adopts a radiation type topological structure and comprises a power supply area, a medium-voltage alternating current bus and an interface between high-voltage backbone networks, wherein the medium-voltage bus is connected with a high-voltage backbone power transmission network through a high-voltage/medium-voltage transformer. The control system of the invention adopts a wireless communication network, can select a mobile operator as a network carrier, and has the advantages of online forever, real-time communication, safety, reliability, wide coverage, strong expansibility and the like.

Description

Power distribution network voltage coordination control system and control method thereof
Technical Field
The invention belongs to the field of power distribution network design and operation control, and particularly relates to a power distribution network voltage coordination control system and a control method thereof.
Background
With the increasing prominence of energy shortages and environmental degradation issues, the load structure and power supply patterns of power distribution networks are undergoing profound changes simultaneously. In the aspect of a load structure, the constant improvement of the energy storage type load proportion of the electric automobile and the like increases the uncertainty of the load side of the power distribution network. While in the power supply mode, distributed renewable power sources are increasingly accessing the power system via the distribution network, so that the power side of the distribution network also exhibits uncertainty. The uncertainty of the load side and the uncertainty of the power supply side are simultaneously improved, so that the difficulty is brought to the safe and efficient operation of the power distribution network, and one of the outstanding problems is the voltage control problem of the power distribution network. Due to double uncertainties of the load side and the power supply side, the amplitude, duration and occurrence frequency of voltage fluctuation of the power distribution network tend to rise, and the voltage fluctuation can seriously affect the power supply quality, system loss and power utilization safety of power distribution network users. Therefore, the voltage regulation and control capability of the power distribution network is improved, and the method has important significance for adapting to changes of a load structure and a power supply mode of the power distribution network.
Currently, the following technical means are mainly adopted in the related measures for improving the voltage and the electric energy quality of the power distribution network: various additional reactive compensation devices are installed in the power distribution network, and the voltage of each node of the medium-voltage bus of the power distribution network is regulated through decentralized local control or centralized coordination control of the reactive compensation devices. From the reactive compensation equipment perspective, the reactive compensation equipment comprises a dynamic voltage restorer, a dynamic voltage regulator, a static reactive compensator and the like. Although these devices can effectively improve the voltage quality of the distribution network, they also have various disadvantages. For example, the dynamic voltage restorer can only deal with the undervoltage problem but cannot deal with the overvoltage problem, the dynamic voltage regulator occupies too large area, and the static var compensator has too large investment. From the structure of the control system, all the reactive compensation equipment under distributed local control completely and independently work, the control system is simple in structure, but all the equipment lack coordination, the overall voltage optimization control target of the power distribution network is difficult to achieve, and the problem of power distribution network loss improvement caused by conflict of the control targets of all the equipment exists; on the contrary, in the centralized coordination control scheme, the monitoring center is often connected with each reactive power compensation device by adopting a wired communication technology, so that the problems of great influence by terrain and environmental factors, long construction period, low expandability and the like exist.
Disclosure of Invention
The invention aims to provide a power distribution network voltage coordination control system and a control method thereof, so as to solve the problems.
In order to achieve the purpose, the invention adopts the following technical scheme:
a power distribution network voltage coordination control system comprises a power distribution network monitoring center, a wireless communication network and nHDesk hybrid distribution transformer and nBA strip bus; the wireless communication network connects each hybrid distribution transformer with the distribution network monitoring center; each hybrid distribution transformer and the monitoring center respectively comprise a wireless transmission module; the power distribution network adopts a radiation type topological structure and comprises a power supply area, a medium-voltage alternating current bus and an interface between high-voltage backbone networks, wherein the medium-voltage bus is connected with a high-voltage backbone power transmission network through a high-voltage/medium-voltage transformer.
Furthermore, the hybrid distribution transformer is connected with the wireless transmission module through an RS232 interface; the wireless transmission module is accessed to a wireless communication network through the wireless transmission module; the communication protocol adopted by the wireless communication network comprises a telecontrol communication protocol, a TCP/IP protocol and a broadband wireless communication protocol; the specific broadband wireless communication protocol selects a GPRS or TD-LTE or WiMAX network.
Further, n is included in the distribution networkBIn the strip bus, n is determined according to a node voltage sensitivity analysis methodHThe strip is used as a key bus, and the rest nB-nHThe bars are non-critical bus bars; n isHThe strip key bus is connected with the medium voltage bus through a hybrid distribution transformer, nB-nHThe strip non-critical feeder is connected to the medium voltage bus by a conventional distribution transformer.
Further, the method comprises the voltage coordination control of each node of the overall loss of the power distribution network, the local voltage control of the hybrid distribution transformer under the condition of the fault of the communication system and the primary side reactive power control of the hybrid distribution transformer.
Further, a node voltage sensitivity coefficient of each node on the medium-voltage bus relative to reactive power on the primary side of each hybrid distribution transformer is calculated, a cost function is established around control targets such as deviation of voltage of each node on the minimized medium-voltage bus and a rated value thereof, overall loss minimization of the power distribution network and the like, and on the premise of meeting node voltage constraint, tidal current equation constraint and power constraint of each hybrid distribution transformer, a primary side reactive power reference instruction of each hybrid distribution transformer is obtained by solving an optimization control problem, so that optimization control of voltage distribution of each node in the power distribution network and improvement of overall operation efficiency of the power distribution network are realized.
Further, under the condition of a wireless communication network fault, a primary side reactive power reference instruction of the hybrid distribution transformer is calculated based on local measurement data information of the hybrid distribution transformer, and voltage regulation of a local bus is achieved.
And further, converting the reactive power reference instruction of the primary side of the hybrid distribution transformer into a q-axis current reference instruction of a parallel converter of the hybrid distribution transformer, and enabling the reactive power of the primary side of the hybrid distribution transformer to follow the reference instruction of the primary side of the hybrid distribution transformer by adjusting the parallel converter based on proportional-integral control and feedforward control logic.
Further, a control method of the power distribution network voltage coordination control system comprises the following steps:
1) at the beginning of each control period, the local controllers of all the hybrid distribution transformers acquire the measured values of the physical quantities of active power, reactive power, voltage and current of all the buses;
2) judging whether the wireless communication network works normally or not; if the voltage is abnormal, the local controller of the hybrid distribution transformer collects the physical quantity measured values of local active power, reactive power, voltage and current collected by the local controller and calculates a primary side reactive power reference signal Q of the hybrid distribution transformer* HDT,i；
3) If the wireless communication network works normally, the power distribution network comprehensive control center obtains the measured values of the physical quantities of active power, reactive power, voltage and current of each bus through the wireless communication network;
4) according to the collected measured values of the physical quantities of the active power, the reactive power, the voltage and the current of each bus, an optimization control problem is established, and the cost function of the problem is as follows:
Figure BDA0002254547200000031
the cost function is intended to solve by solving for nHOptimal value of primary side reactive power increment Δ Q of each of the hybrid distribution transformers* HDT,iMinimizing n in the distribution networkBVoltage V of each nodeMV,jTo a rated value V* MVWhile minimizing overall losses within the distribution grid; wherein KQ,iAs the node voltage sensitivity coefficient, RijIs the resistance of the ij branch, PijFor the ij branch active power, QijReactive power of an ij branch; the optimization control model considers the following constraint conditions:
a) the power flow equation constraint comprises active power flow constraint and reactive power flow constraint on a medium-voltage alternating current bus;
Figure BDA0002254547200000041
Figure BDA0002254547200000042
wherein NB represents a set of nodes immediately adjacent to node j;
b) node voltage constraint, ensuring that the voltage of each node on the medium-voltage bus is between 0.95 and 1.05 times of the rated value of the node;
Figure BDA0002254547200000043
c) power constraint of hybrid distribution transformers to ensure active power P of each hybrid distribution transformerHDT,iAnd reactive power QHDT,iIs less than its rated apparent power SHDTn,iSquare of (d);
Figure BDA0002254547200000044
5) solving the nonlinear optimization control problem to obtain the primary side reactive power reference value Q of each hybrid distribution transformer* HDT,i(ii) a The reference values are used as control signals and are transmitted to the local controllers of the hybrid distribution transformers through the GPRS wireless communication network for specific execution.
Compared with the prior art, the invention has the following technical effects:
the hybrid distribution transformer is only needed to be arranged at the key bus in the distribution network, so that the investment cost is saved. Compared with the traditional distribution transformer, the hybrid distribution transformer obviously improves the regulation and control capability of the distribution network on the premise that the investment cost is not obviously increased. Meanwhile, under the condition of power electronic device failure, the hybrid distribution transformer can continue to operate in a traditional transformer mode, and has high reliability and fault-tolerant capability.
The control strategy of the invention can realize the coordinated optimization control of a plurality of hybrid distribution transformers, optimize the node voltage distribution on the medium-voltage bus of the distribution network, and minimize the square sum of errors between each node voltage and a rated value, thereby reducing the voltage fluctuation on the medium-voltage bus of the distribution network. Meanwhile, the control strategy can also minimize the overall loss of the power distribution network and improve the operation efficiency of the power distribution network.
The control system of the invention adopts a wireless communication network, can select a mobile operator as a network carrier, and has the advantages of online forever, real-time communication, safety, reliability, wide coverage, strong expansibility and the like.
When the wireless communication system has faults or serious delay, the control system based on the wireless communication network can be switched to a local control mode, so that the requirement of local bus voltage control is met to the greatest extent, and the fault tolerance is better.
Drawings
Fig. 1 is a structural diagram of a power distribution network voltage coordination control system based on a hybrid distribution transformer and wireless communication according to the invention.
Fig. 2 is a schematic diagram of a hybrid distribution transformer used in the present invention.
Fig. 3 is a hybrid distribution transformer local controller and wireless communication module architecture diagram.
FIG. 4 is a block diagram of a medium voltage bus node voltage coordination control architecture.
Fig. 5 is a flow chart of the voltage coordination control of the distribution network based on the hybrid distribution transformer and wireless communication.
Fig. 6 is a block diagram of local control of the node voltage of the power distribution network in a fault state of the wireless communication network.
Detailed Description
The invention is further described below with reference to the accompanying drawings:
for better clarity of the description of the objects, technical solutions and advantages of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, a power distribution network voltage coordination control system including a hybrid power distribution transformer and wireless communication according to the present invention includes a power distribution network monitoring center, a wireless communication network, and nHPlatform hybrid distribution transformer, nBAnd (4) a strip bus. Where n isHAnd nBAre all natural numbers greater than or equal to 1.
The medium-voltage bus of the controlled power distribution network is connected with the high-voltage main transmission network through a high-voltage/medium-voltage transformer, and a radiation type topological structure is adopted to connect all the low-voltage buses. Assuming that the load change of each low-voltage bus follows mutually independent Gaussian distribution, obtaining the sensitivity of each node voltage relative to the reactive power of each low-voltage bus based on the Jacobian matrix, sequencing according to the sensitivity, and sequencing at nBFinding sensitivity n in bar low voltage busHThe strip is used as a key bus, and the rest is (n)B-nH) The strip low-voltage feeder serves as a non-critical bus. The key bus bar and the medium voltage bus bar are connected by a hybrid distribution transformer as shown in figure 2.
See FIG. 2, T1The main transformer in the hybrid distribution transformer is used for transmitting power of a distribution network to a low-voltage feeder line W1、W2、W3Are respectively T1The primary side winding, the secondary side winding and the control winding. Wherein W1Connected to medium-voltage busbars of the distribution network, W2Connected to low-voltage feeders, W3With parallel converters CVpAre connected. In the figure T2An isolation transformer in a hybrid distribution transformer is responsible for a small fraction of the load supply when the secondary side voltage deviates from the rated value. W4And W5Are respectively T2Of the converter-side winding and of the network-side winding, W4With series converters CVsAre connected to each other by W5And W1Are connected in series. CV ofpAnd CVsBack-to-back connection is achieved through a DC link, wherein CV ispIs responsible for controlling the voltage and T of the direct current link1Primary side reactive power, CVsAnd is responsible for controlling the secondary side voltage.
The architecture of the local control system of the hybrid distribution transformer is shown in fig. 3. The communication module of the local controller of the hybrid distribution transformer in the embodiment adopts a GPRS module, but in specific implementation, other communication modules such as WiMAX, TD-LTE, β -network communication and the like may be replaced according to actual situations. And the GPRS wireless communication module is connected with a local control system of the hybrid distribution transformer through an RS232 interface. A local control system for a hybrid distribution transformer includes a CVpController and CVsAnd a controller. Wherein CV ispController for collecting local reactive power Q of hybrid distribution transformerHDTSecondary side current iLabcPrimary side current isabc、CVpOutput current i3abcObtaining the local reactive power reference value Q of the hybrid distribution transformer from the monitoring center through the GPRS wireless communication module* HDTFrom which CV is calculatedpModulating signals, actually controlling CVp. The modulation signal is calculated based on a vector control and feed forward control method, the detailed block diagram of which is shown in fig. 4.
Referring to the flow chart of the coordinated control of the voltage of the distribution network based on the hybrid distribution transformers and the wireless communication shown in fig. 5, under the support of the wireless communication network, the control of the voltage of the medium-voltage bus node of the distribution network is cooperatively realized by a comprehensive control center of the distribution network and a local controller of each hybrid distribution transformer. The coordination control method will now be explained:
1) at the beginning of each control cycle, the local controller of each hybrid distribution transformer collects the measured values of physical quantities of active power, reactive power, voltage, current, etc. of each bus.
2) And judging whether the wireless communication network works normally. If the voltage is abnormal, the local controller of the hybrid distribution transformer collects the physical quantity measured values of local active power, reactive power, voltage, current and the like collected by the local controller, and calculates a primary side reactive power reference signal Q of the hybrid distribution transformer* HDT,iThe computational block diagram is shown in fig. 6.
2) If the wireless communication network works normally, the power distribution network comprehensive control center obtains the measured values of physical quantities such as active power, reactive power, voltage, current and the like of each bus through the wireless communication network;
2) according to the collected measured values of physical quantities such as active power, reactive power, voltage, current and the like of each bus, an optimization control problem is established, and the cost function of the problem is as follows:
Figure BDA0002254547200000071
the cost function is intended to solve by solving for nHOptimal value of primary side reactive power increment Δ Q of each of the hybrid distribution transformers* HDT,iMinimizing n in the distribution networkBVoltage V of each nodeMV,jTo a rated value V* MVWhile minimizing the overall losses over the distribution network. Wherein KQ,iAs the node voltage sensitivity coefficient, RijIs the resistance of the ij branch, PijFor the ij branch active power, QijAnd the reactive power of the ij branch is obtained. The optimization control model considers the following constraint conditions:
a) and (4) power flow equation constraints comprising active power flow constraints and reactive power flow constraints on the medium-voltage alternating-current bus.
Figure BDA0002254547200000082
Where NB represents the set of nodes immediately adjacent to node j.
b) And node voltage constraint, which ensures that each node voltage on the medium-voltage bus is between 0.95 and 1.05 times of the rated value of each node voltage.
Figure BDA0002254547200000083
c) Power constraint of hybrid distribution transformers to ensure active power P of each hybrid distribution transformerHDT,iAnd reactive power QHDT,iIs less than its rated apparent power SHDTn,iSquare of (d).
Figure BDA0002254547200000084
3) Solving the nonlinear optimization control problem to obtain the primary side reactive power reference value Q of each hybrid distribution transformer* HDT,i. The reference values are used as control signals and are transmitted to the local controllers of the hybrid distribution transformers through the GPRS wireless communication network for specific execution.
Therefore, the optimal reactive power set value of the primary side of each hybrid distribution transformer is calculated through the comprehensive control center of the power distribution network, and the local controller of each hybrid distribution transformer drives the hybrid distribution transformer to track the optimal reactive power set value, so that the optimal control of the voltage distribution of the medium-voltage bus nodes of the power distribution network can be realized.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (8)

1. A power distribution network voltage coordination control system is characterized by comprising a power distribution network monitoring center, a wireless communication network and nHDesk hybrid distribution transformer and nBA strip bus; the wireless communication network connects each hybrid distribution transformer with the distribution network monitoring center; each hybrid distribution transformer and the monitoring center respectively comprise a wireless transmission module; the power distribution network adopts a radiation type topological structure and comprises a power supply area, a medium-voltage alternating current bus and an interface between high-voltage backbone networks, wherein the medium-voltage bus is connected with a high-voltage backbone power transmission network through a high-voltage/medium-voltage transformer.
2. The system of claim 1, wherein the hybrid distribution transformer is connected to the wireless transmission module via an RS232 interface; the wireless transmission module is accessed to a wireless communication network through the wireless transmission module; the communication protocol adopted by the wireless communication network comprises a telecontrol communication protocol, a TCP/IP protocol and a broadband wireless communication protocol; the specific broadband wireless communication protocol selects a GPRS or TD-LTE or WiMAX network.
3. The system of claim 1, wherein the distribution network comprises nBIn the strip bus, n is determined according to a node voltage sensitivity analysis methodHThe strip is used as a key bus, and the rest nB-nHThe bars are non-critical bus bars; n isHThe strip key bus is connected with the medium voltage bus through a hybrid distribution transformer, nB-nHThe strip non-critical feeder is connected to the medium voltage bus by a conventional distribution transformer.
4. The system of claim 1, comprising coordinated control of node voltage of overall loss of the distribution network, local voltage control of the hybrid distribution transformer in case of communication system failure, and primary side reactive power control of the hybrid distribution transformer.
5. The system of claim 4, wherein a node voltage sensitivity coefficient of each node on the medium-voltage bus with respect to the primary side reactive power of each hybrid distribution transformer is calculated, a cost function is established around control targets such as deviation of each node voltage on the medium-voltage bus from a rated value thereof and minimization of overall loss of the distribution network, and on the premise that node voltage constraints, power flow equation constraints and power constraints of each hybrid distribution transformer are met, the primary side reactive power reference instruction of each hybrid distribution transformer is obtained by solving an optimization control problem, so that optimization control of voltage distribution of each node in the distribution network and improvement of overall operating efficiency of the distribution network are achieved.
6. The system of claim 4, wherein in the event of a wireless communication network failure, the primary side reactive power reference command of the hybrid distribution transformer is calculated based on the local measurement data information of the hybrid distribution transformer, so as to adjust the voltage of the local bus.
7. The system of claim 4, wherein the primary side reactive power reference command of the hybrid distribution transformer is converted into a q-axis current reference command of the parallel converters thereof, and the primary side reactive power of the hybrid distribution transformer is made to follow the reference command thereof by adjusting the parallel converters based on proportional-integral control and feed-forward control logic.
8. A control method of a power distribution network voltage coordination control system, which is based on any one of claims 1 to 7, and comprises the following steps:
1) at the beginning of each control period, the local controllers of all the hybrid distribution transformers acquire the measured values of the physical quantities of active power, reactive power, voltage and current of all the buses;
2) judging whether the wireless communication network works normally or not; if not, mixThe local controller of the combined distribution transformer collects the physical quantity measured values of local active power, reactive power, voltage and current collected by the local controller and calculates a primary side reactive power reference signal Q of the combined distribution transformer* HDT,i；
3) If the wireless communication network works normally, the power distribution network comprehensive control center obtains the measured values of the physical quantities of active power, reactive power, voltage and current of each bus through the wireless communication network;
4) according to the collected measured values of the physical quantities of the active power, the reactive power, the voltage and the current of each bus, an optimization control problem is established, and the cost function of the problem is as follows:
the cost function is intended to solve by solving for nHOptimal value of primary side reactive power increment Δ Q of each of the hybrid distribution transformers* HDT,iMinimizing n in the distribution networkBVoltage V of each nodeMV,jTo a rated value V* MVWhile minimizing overall losses within the distribution grid; wherein KQ,iAs the node voltage sensitivity coefficient, RijIs the resistance of the ij branch, PijFor the ij branch active power, QijReactive power of an ij branch; the optimization control model considers the following constraint conditions:
a) the power flow equation constraint comprises active power flow constraint and reactive power flow constraint on a medium-voltage alternating current bus;
Figure FDA0002254547190000031
Figure FDA0002254547190000032
wherein NB represents a set of nodes immediately adjacent to node j;
b) node voltage constraint, ensuring that the voltage of each node on the medium-voltage bus is between 0.95 and 1.05 times of the rated value of the node;
Figure FDA0002254547190000033
c) power constraint of hybrid distribution transformers to ensure active power P of each hybrid distribution transformerHDT,iAnd reactive power QHDT,iIs less than its rated apparent power SHDTn,iSquare of (d);
Figure FDA0002254547190000034
5) solving the nonlinear optimization control problem to obtain the primary side reactive power reference value Q of each hybrid distribution transformer* HDT,i(ii) a The reference values are used as control signals and are transmitted to the local controllers of the hybrid distribution transformers through the GPRS wireless communication network for specific execution.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109888791A (en) * 2019-01-25 2019-06-14 西安交通大学 A kind of active distribution network and its control method based on hybrid distribution transformer
CN111404161A (en) * 2020-04-16 2020-07-10 北京慧和仕科技有限责任公司 Intelligent power consumption management and inter-station-area mutual-aid transfer system and method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106451473A (en) * 2016-11-03 2017-02-22 成都信息工程大学 Fuzzy multi-agent based distribution network multi-target voltage control system
CN108988402A (en) * 2018-07-26 2018-12-11 国网辽宁省电力有限公司经济技术研究院 Alternating current-direct current power distribution network optimal control method based on Optimized Operation
CN109888791A (en) * 2019-01-25 2019-06-14 西安交通大学 A kind of active distribution network and its control method based on hybrid distribution transformer
CN110112741A (en) * 2019-03-26 2019-08-09 天津大学 High permeability photovoltaic power distribution network Optimization Scheduling based on electric power electric transformer

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106451473A (en) * 2016-11-03 2017-02-22 成都信息工程大学 Fuzzy multi-agent based distribution network multi-target voltage control system
CN108988402A (en) * 2018-07-26 2018-12-11 国网辽宁省电力有限公司经济技术研究院 Alternating current-direct current power distribution network optimal control method based on Optimized Operation
CN109888791A (en) * 2019-01-25 2019-06-14 西安交通大学 A kind of active distribution network and its control method based on hybrid distribution transformer
CN110112741A (en) * 2019-03-26 2019-08-09 天津大学 High permeability photovoltaic power distribution network Optimization Scheduling based on electric power electric transformer

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
CHANDAN KUMAR等: "Smart Transformer Based Loop Power Controller in Radial Power Distribution Grid", 《2018 IEEE PES INNOVATIVE SMART GRID TECHNOLOGIES CONFERENCE EUROPE (ISGT-EUROPE)》 *
YIBIN LIU等: "Design and Analysis of the Compounded Control System of Hybrid Distribution Transformer", 《2018 IEEE ENERGY CONVERSION CONGRESS AND EXPOSITION (ECCE)》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109888791A (en) * 2019-01-25 2019-06-14 西安交通大学 A kind of active distribution network and its control method based on hybrid distribution transformer
CN111404161A (en) * 2020-04-16 2020-07-10 北京慧和仕科技有限责任公司 Intelligent power consumption management and inter-station-area mutual-aid transfer system and method
CN111404161B (en) * 2020-04-16 2023-06-20 北京慧和仕科技有限责任公司 Intelligent electricity management and inter-station mutual-aid transfer system and method

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