WO2018196381A1 - 双极电压源换流器无源控制方法、装置及存储介质 - Google Patents

双极电压源换流器无源控制方法、装置及存储介质 Download PDF

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WO2018196381A1
WO2018196381A1 PCT/CN2017/114074 CN2017114074W WO2018196381A1 WO 2018196381 A1 WO2018196381 A1 WO 2018196381A1 CN 2017114074 W CN2017114074 W CN 2017114074W WO 2018196381 A1 WO2018196381 A1 WO 2018196381A1
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pole
voltage
vsc
reference value
axis
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French (fr)
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王瑶
郝俊芳
严兵
王柏恒
孔令凯
张群
范雪峰
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Xuji Group Co Ltd
XJ Electric Co Ltd
State Grid Corp of China SGCC
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Xuji Group Co Ltd
XJ Electric Co Ltd
State Grid Corp of China SGCC
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—ELECTRIC POWER NETWORKS; 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
    • H02J3/36—Arrangements for transfer of electric power between AC networks via high-voltage DC [HVDC] links; Arrangements for transfer of electric power between generators and networks via HVDC links
    • 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
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

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  • the invention relates to the technical field of direct current transmission, in particular to a method, a device and a storage medium for passive control of a voltage source converter (VSC).
  • VSC voltage source converter
  • Line Commutated Converter Based High Voltage Direct Current (LCC-HVDC) has been widely used in large-capacity long-distance transmission and back-to-back interconnection of asynchronous grids, but there are inverter station exchanges.
  • MMC-HVDC Modular Multilevel Converter Based High Voltage Direct Current
  • the inverter side VSC terminal can operate in both active mode and passive mode.
  • active mode the VSC terminal module is actively charged via its connected AC grid; in passive mode, the VSC terminal module is passively charged via its connected DC line. After the charging is completed, the VSC is unlocked according to the corresponding control mode in the two modes to realize the power transmission of the DC transmission system.
  • embodiments of the present invention are directed to providing a bipolar VSC passive control method, apparatus, and storage medium, and at least solving the unlock control problem of a DC system having a bipolar VSC accessing the same passive network.
  • an embodiment of the present invention provides a bipolar VSC passive control method, including:
  • the first pole VSC and the second pole VSC on the inverter side are passively charged by a DC voltage supplied from the rectification side;
  • a constant AC voltage control is applied to the first pole VSC to obtain a three-phase modulation reference voltage of the first pole VSC, thereby establishing a grid side AC voltage; and controlling the inverter side
  • the two-pole VSC phase-locks the phase of the network-side AC voltage established by the first pole VSC, and controls the second pole VSC to unlock after phase-locking.
  • the predetermined AC voltage is controlled as:
  • the first pole modulation voltage d-axis reference value is calculated by the following formula:
  • U d1_ref is the d-axis reference value of the first-pole modulation voltage
  • K p is a proportional coefficient. It is the standard value of the network side AC voltage reference value U ac_ref
  • U ac_d is the grid side voltage d-axis component
  • T i is the integral time constant
  • the first pole modulation voltage q-axis reference value U q1_ref is calculated by the following formula:
  • U q1_ref is the first-pole modulation voltage q-axis reference value
  • K p is the proportional coefficient
  • U ac_q is the grid-side voltage q-axis component
  • T i is the integration time constant
  • the outer loop is a power loop
  • the inner loop is a current loop
  • the double loop control in which the outer loop is a power loop and the inner loop is a current loop includes: proportional and integral (Proportional Integral, PI) control on the difference between the active power reference value and the measured value of the active power, and the inner loop current is obtained.
  • proportional and integral Proportional Integral, PI
  • the d-axis reference value is subjected to PI control for the difference between the reactive power reference value and the measured value of the reactive power to obtain an inner loop current q-axis reference value, the inner loop current d-axis reference value and the inner loop current q-axis reference
  • the value passes through the inner loop current controller to obtain the second pole modulation voltage d-axis reference value and the second pole modulation voltage q-axis reference value respectively, and performs Parker inverse transformation to obtain a three-phase modulation voltage reference value of the second pole VSC.
  • an embodiment of the present invention further provides a bipolar VSC passive control apparatus, including: a charging unit and an unlocking control unit, where:
  • a charging unit configured to passively charge the first pole VSC and the second pole VSC of the inverter side through a DC voltage provided by the rectifying side;
  • the unlocking control unit is configured to control the first pole VSC of the inverter side to be unlocked, and adopt a constant AC voltage control on the first pole VSC to obtain a three-phase modulation reference voltage of the first pole VSC, thereby establishing a grid side AC voltage;
  • the second pole VSC of the control inverter side phase-locks the phase of the grid-side AC voltage established by the first pole VSC, and controls the second pole VSC to unlock after phase locking.
  • the unlocking control unit is further configured to perform corresponding processing on the difference between the grid side AC voltage reference value and the grid side voltage d-axis component to obtain a first pole modulation voltage d-axis reference value;
  • the difference between the voltage q-axis components is processed correspondingly to obtain a first-pole modulation voltage q-axis reference value, and the first-pole modulation voltage d-axis reference value and the first-pole modulation voltage q-axis reference value are inversely transformed by the Parker to obtain a Parker inverse transform.
  • the unlocking control unit includes a calculating unit configured to calculate the d-axis reference value of the first pole modulation voltage by using the following formula:
  • U d1_ref is the d-axis reference value of the first-pole modulation voltage
  • K p is a proportional coefficient. It is the standard value of the network side AC voltage reference value U ac_ref
  • U ac_d is the grid side voltage d-axis component
  • T i is the integral time constant
  • U q1_ref is the first-pole modulation voltage q-axis reference value
  • K p is the proportional coefficient
  • U ac_q is the grid-side voltage q-axis component
  • T i is the integration time constant
  • the device further includes:
  • the dual-loop control unit is configured to use the double loop control in which the outer loop is a power loop and the inner loop is a current loop after the second pole VSC is unlocked.
  • the dual-loop control unit is further configured to perform PI control on the difference between the active power reference value and the measured value of the active power to obtain an inner loop current d-axis reference value, and the reactive power reference value and the reactive power measured value.
  • the difference is PI controlled to obtain an inner loop current q-axis reference value
  • the inner loop current d-axis reference value and the inner loop current q-axis reference value are passed through an inner loop current controller to obtain a second pole modulation voltage d-axis, respectively.
  • the reference value and the second-pole modulation voltage q-axis reference value are subjected to Parker inverse transform to obtain a three-phase modulation voltage reference value of the second pole VSC.
  • the embodiment of the present invention further provides a computer storage medium storing a computer program configured to perform the above-described bipolar VSC passive control method of the embodiment of the present invention.
  • the bipolar VSC passive control method, device and storage medium applying the embodiments of the present invention have the following beneficial effects:
  • FIG. 1 is a schematic topological structural diagram of a bipolar passive hybrid DC power transmission system according to an embodiment of the present invention
  • FIG. 2 is a schematic diagram of a topological structure of one of the VSCs in the bipolar VSC according to the embodiment of the present invention
  • FIG. 3 is a schematic block diagram of a pole 1 controller of a bipolar VSC according to an embodiment of the present invention
  • FIG. 4 is a schematic block diagram of a pole 2 controller of a bipolar VSC according to an embodiment of the present invention
  • FIG. 5 is a schematic structural diagram of a bipolar VSC passive control apparatus according to an embodiment of the present invention.
  • the bipolar passive hybrid DC transmission system uses LCC to access the AC grid on the rectifier side, VSC to the passive network on the inverter side, and the power to the VSC terminal through the DC line on the LCC side.
  • the side string has a smoothing reactor
  • the DC side of the VSC terminal has a diode
  • the VSC end adopts an MMC structure
  • the inverter consists of three phases of six bridge arms, each of which is composed of a bridge arm inductance and a same number of submodules.
  • the submodule uses a half-bridge structure consisting of two IGBTs, two anti-parallel diodes, and one storage capacitor.
  • the bipolar LCC terminal on the rectifier side is controlled to be unlocked, and the stable DC voltage provided by the bipolar LCC is used for the pole 1 and pole 2 of the inverter side (the first pole to be unlocked in the bipolar VSC) VSC is called pole 1, and the capacitor in the sub-module of the pole-locked VSC is called pole 2).
  • the VSC terminal 1 is unlocked.
  • the constant-voltage voltage is controlled to establish the VSC-side communication. Three-phase voltage on the side.
  • the VSC terminal 1 and the pole 2 are connected in the same passive network, after the VSC terminal 1 is unlocked, the AC voltage is already present on the AC side, and the control pole 2 is phase-locked to the voltage phase of the pole 1 output.
  • the voltage phase of the pole 2 is synchronized with the voltage phase of the pole 1, and then the pole 2 is unlocked by the fixed power control and the fixed reactive power control.
  • the power distribution of the two poles can be completed by controlling the active power and the reactive power value outputted by the pole 2, and the bipolar coordinated control of the active power and the reactive power is realized.
  • the VSC terminal 1 is unlocked by using a constant AC voltage control, and the control process includes:
  • the difference between the standard value of the grid-side AC voltage reference value U ac_ref and the grid-side voltage d-axis component U ac_d is controlled to obtain a first-pole modulation voltage d-axis reference value U d1_ref , which is 0 and
  • the difference between the side voltage q-axis components U ac — q is controlled to obtain a first-pole modulation voltage q-axis reference value U q1 — ref
  • the inverse Park inverse transform is performed to obtain the three-phase modulation voltage reference values U a1 — ref , U b1 — ref , and U c1 — ref of the pole 1 .
  • U ac_ref increases from 0 with a certain slope, so that the established network side AC voltage rises steadily.
  • the difference between the active power reference value P ac — ref and the active power measured value P ac — meas is PI controlled to obtain an inner loop current d-axis reference value I d — ref , and the reactive power reference value Q ac — ref and reactive power are measured.
  • the difference of the value Q ac_meas is PI controlled, and the inner loop current q-axis reference value I q_ref is obtained, and the second-pole modulation voltage d-axis reference value U d2_ref and the second-pole modulation voltage q-axis reference value U are respectively obtained by the inner loop current controller.
  • Q2_ref performing Parker inverse transform to obtain the three-phase modulation voltage reference values U a2_ref , U b2_ref , U c2_ref of the pole 2.
  • P ac_ref and Q ac_ref increase or decrease from 0 at a certain rate of increase and decrease, so that the active power and reactive power of the output change smoothly.
  • pole 2 fails, pole 2 is out of service, pole 1 continues to run; if pole 1 fails, pole 1 is out of service, and pole 2 control strategy switches to constant AC voltage control and continues to run.
  • the DC voltage is established after unlocking the RCC side of the rectification side, and the sub-module of the VSC end of the inverter side is passively charged through the DC line, and then the VSC terminal 1 is unlocked, thereby establishing the AC side three-phase voltage of the VSC terminal, and An AC voltage is generated on the AC side of the VSC terminal 2, and finally, the voltage phase of the pole 2 is locked, and the pole 2 is unlocked by the fixed power and the constant reactive power control.
  • the power distribution of the two poles can be completed by the active power and the reactive power value outputted by the control pole 2, and the bipolar coordinated control of the active power and the reactive power is realized, the logic is simple, the engineering is easy to implement, and the two poles can be realized.
  • the VSC is smoothly unlocked while providing stable power to the same passive network.
  • the bipolar VSC passive control method of the above-mentioned DC power transmission system is not only applicable to the bipolar passive hybrid DC transmission system shown in FIG. 1 , that is, the rectifier side converter is not applicable. Limited to LCC, it can also be a bipolar VSC or other type of inverter, as long as the converter on the rectification side can provide a stable DC voltage to the inverter side.
  • the manner of unlocking the bipolar LCC can be set according to requirements, and the capacitor of the VSC terminal 1 and the pole 2 can be charged by simultaneously unlocking the bipolar LCC, and the pole 1 and the pole 2 are unlocked after the charging is completed; First unlock the LCC of the pole 1 and then unlock the pole 2 LCC, then unlock the pole 1 and pole 2; you can also unlock the two sides of the rectifier side and the inverter side separately, such as unlocking the pole 1 After LCC, the pole 1 of the VSC terminal is unlocked, the LCC of the pole 2 is unlocked, and the pole 2 of the VSC terminal is finally unlocked.
  • FIG. 5 is a schematic structural diagram of a bipolar VSC passive control device according to an embodiment of the present invention. As shown in FIG. 5, the charging unit 51 and the unlocking control unit are included. 52,
  • the charging unit 51 is configured to passively charge the DC voltage provided by the rectifying side of the first pole VSC and the second pole VSC on the inverter side;
  • the unlocking control unit 52 is configured to control the first pole VSC of the inverter side to be unlocked, and adopt a constant AC voltage control on the first pole VSC to obtain a three-phase modulation reference voltage of the first pole VSC;
  • the two-pole VSC phase-locks the phase of the three-phase AC voltage output by the first pole VSC, and controls the second pole VSC to unlock after phase locking.
  • the unlocking control unit 52 is further configured to perform a corresponding processing on the difference between the grid side AC voltage reference value and the grid side voltage d-axis component to obtain a first pole modulation voltage d-axis reference value;
  • the unlocking control unit 52 includes a calculating unit 521 configured to calculate the first pole modulation voltage d-axis reference value by:
  • U d1_ref is the d-axis reference value of the first-pole modulation voltage
  • K p is a proportional coefficient. It is the standard value of the network side AC voltage reference value U ac_ref
  • U ac_d is the grid side voltage d-axis component
  • T i is the integral time constant
  • U q1_ref is the first-pole modulation voltage q-axis reference value
  • K p is the proportional coefficient
  • U ac_q is the grid-side voltage q-axis component
  • T i is the integration time constant
  • the apparatus further includes:
  • the double loop control unit 53 is configured to use the double loop control in which the outer loop is a power loop and the inner loop is a current loop after the second pole VSC is unlocked.
  • the dual-loop control unit 53 is further configured to perform PI control on the difference between the active power reference value and the measured value of the active power to obtain an inner loop current d-axis reference value, and the reactive power reference value and reactive power.
  • the difference between the measured values of the power is PI controlled, and the inner loop current q-axis reference value is obtained, and the inner loop current d-axis reference value and the inner loop current q-axis reference value are respectively obtained by the inner loop current controller to obtain the second pole modulation respectively.
  • the voltage d-axis reference value and the second pole modulation voltage q-axis reference value are inversely converted by Park to obtain a three-phase modulation voltage reference value of the second pole VSC.
  • the bipolar VSC passive control device described in the above embodiment is actually a computer solution based on the method flow of the present invention, that is, a software architecture, which can be applied to a converter station, and the above device is a method and method The process corresponding to the process. Since the introduction of the above method is sufficiently clear and complete, and the device claimed in this embodiment is actually a software architecture, it will not be described in detail.
  • embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention can take the form of a hardware embodiment, a software embodiment, or a combination of software and hardware. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) including computer usable program code.
  • the computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device.
  • the apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.
  • These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device.
  • the instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.
  • the first pole VSC and the second pole VSC of the inverter side are passively charged by the DC voltage provided by the rectification side; after the first pole VSC of the inverter side is unlocked, the first pole VSC is adopted.
  • the AC voltage is controlled to obtain a three-phase modulation reference voltage of the first pole VSC, thereby establishing a grid-side AC voltage; and controlling the second pole VSC of the inverter side to lock the phase of the grid-side AC voltage established by the first pole VSC Phase, after the phase lock, controls the second pole VSC to unlock.
  • the smooth unlocking of the two-pole VSC is realized, and the voltage phases of the two-pole VSCs are kept synchronized after the unlocking, and at the same time, the same passive network is stably supplied with power.

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  • Charge And Discharge Circuits For Batteries Or The Like (AREA)
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Abstract

一种双极电压源换流器(VSC)无源控制方法、装置及存储介质，其中，方法包括：通过控制逆变侧的其中一极VSC解锁后，对其采用定交流电压控制，然后控制逆变侧的另一极VSC对上述其中一极VSC输出的相位进行锁相，锁相后控制另一极VSC解锁。能够实现两极VSC的平稳解锁，解锁后两极VSC的电压相位保持同步，并同时为同一无源网络稳定供电。

Description

双极电压源换流器无源控制方法、装置及存储介质
相关申请的交叉引用
本申请基于申请号为201710287488.4、申请日为2017年04月27日的中国专利申请提出，并要求该中国专利申请的优先权，该中国专利申请的全部内容在此引入本申请作为参考。
技术领域
本发明涉及直流输电技术领域，尤其涉及双极电压源换流器(Voltage Source Converter，VSC)无源控制方法、装置及存储介质。
背景技术
电网换相换流器高压直流输电系统(Line Commutated Converter Based High Voltage Direct Current，LCC-HVDC)已广泛地应用于大容量远距离输电和异步电网背靠背互联等场合，但其存在着逆变站换相失败、无法对无源系统供电、运行过程中需要消耗大量无功功率等缺点；而以全控型电力电子器件为基础的电压源型换流器高压直流输电系统(Voltage Source Converter Based High Voltage Direct Current，VSC-HVDC)具有可独立控制有功功率和无功功率、不存在换相失败和可对无源系统供电等优点，但其较LCC建设成本高、输送容量小。在众多的VSC-HVDC输电拓扑中，模块化多电平换流器直流输电系统(Modular Multilevel Converter Based High Voltage Direct Current，MMC-HVDC)具备VSC-HVDC所有的优点，但由于其造价昂贵、无法有效处理直流故障等缺点，使其不适合运用于长距离、大功率输电场合。
为了综合LCC-HVDC和VSC-HVDC这两种直流输电系统的优势，混合直流输电系统应运而生。混合直流输电系统的整流侧采用LCC，逆变侧 采用VSC，充分发挥了LCC直流输电系统容量大、距离远以及VSC不存在换相失败并可向无源交流系统供电的优点，具有较大的发展前景。
通常，在混合直流输电系统中，逆变侧VSC端可工作于有源模式和无源模式两种运行方式下。有源模式时，VSC端子模块通过其连接的交流电网进行有源充电；无源模式时，VSC端子模块通过其连接的直流线路进行无源充电。充电完成后，两种模式下VSC按照相应的控制方式解锁，实现直流输电系统的功率传输。
而直流系统中逆变侧的双极VSC接入同一无源网络时，仅采用整流侧提供的直流电压为两极VSC充电并解锁的方式，会在两极VSC解锁后存在电压的相位偏差，当两极VSC的电压相位偏差很大时，会对无源网络造成一定的冲击，冲击严重时将会导致直流输电系统不能稳定工作。并且，采用上述整流侧提供的直流电压为两极VSC充电并解锁的方式时，还存在两极VSC的功率协调控制问题。
发明内容
有鉴于此，本发明实施例期望提供一种双极VSC无源控制方法、装置及存储介质，至少解决具有双极VSC的直流系统接入同一无源网络的解锁控制问题。
为解决上述技术问题，本发明实施例提出一种双极VSC无源控制方法，包括：
逆变侧的第一极VSC和第二极VSC通过整流侧提供的直流电压进行无源充电；
控制逆变侧的第一极VSC解锁后，对所述第一极VSC采用定交流电压控制，得到第一极VSC的三相调制参考电压，从而建立网侧交流电压；控制逆变侧的第二极VSC对所述第一极VSC建立的网侧交流电压的相位进行锁相，锁相后控制所述第二极VSC解锁。
上述方案中，所述定交流电压控制为：
对网侧交流电压参考值与网侧电压d轴分量的差进行相应的处理，得到第一极调制电压d轴参考值；
对0与网侧电压q轴分量的差进行相应的处理，得到第一极调制电压q轴参考值，对所述第一极调制电压d轴参考值和第一极调制电压q轴参考值进行帕克反变换，得到第一极VSC的三相调制参考电压值。
上述方案中，所述第一极调制电压d轴参考值通过下式计算得到：
Figure PCTCN2017114074-appb-000001
式中，Ud1_ref为第一极调制电压d轴参考值，Kp为比例系数，
Figure PCTCN2017114074-appb-000002
为网侧交流电压参考值Uac_ref的标幺值，Uac_d为网侧电压d轴分量，Ti为积分时间常数；
所述第一极调制电压q轴参考值Uq1_ref通过下式计算得到：
Figure PCTCN2017114074-appb-000003
式中，Uq1_ref为第一极调制电压q轴参考值，Kp为比例系数，Uac_q为网侧电压q轴分量，Ti为积分时间常数。
上述方案中，所述第二极VSC解锁后采用外环为功率环、内环为电流环的双环控制。
上述方案中，所述外环为功率环、内环为电流环的双环控制包括：对有功功率参考值与有功功率实测值的差进行比例和积分(Proportional Integral，PI)控制，得到内环电流d轴参考值，对无功功率参考值与无功功率实测值的差进行PI控制，得到内环电流q轴参考值，所述内环电流d轴参考值和所述内环电流q轴参考值经过内环电流控制器，分别得到第二极调制电压d轴参考值和第二极调制电压q轴参考值，进行帕克反变换，得到第二极VSC的三相调制电压参考值。
为解决上述问题，本发明实施例还提出一种双极VSC无源控制装置，包括：充电单元和解锁控制单元，其中：
充电单元，配置为通过整流侧提供的直流电压对逆变侧的第一极VSC和第二极VSC进行无源充电；
解锁控制单元，配置为控制逆变侧的第一极VSC解锁后，对所述第一极VSC采用定交流电压控制，得到第一极VSC的三相调制参考电压，从而建立网侧交流电压；控制逆变侧的第二极VSC对所述第一极VSC建立的网侧交流电压的相位进行锁相，锁相后控制所述第二极VSC解锁。
上述方案中，所述解锁控制单元，还配置为对网侧交流电压参考值与网侧电压d轴分量的差进行相应的处理，得到第一极调制电压d轴参考值；对0与网侧电压q轴分量的差进行相应的处理，得到第一极调制电压q轴参考值，对所述第一极调制电压d轴参考值和第一极调制电压q轴参考值进行帕克反变换，得到第一极VSC的三相调制参考电压值。
上述方案中，所述解锁控制单元包括计算单元，配置为通过下式计算得到所述第一极调制电压d轴参考值：
Figure PCTCN2017114074-appb-000004
式中，Ud1_ref为第一极调制电压d轴参考值，Kp为比例系数，
Figure PCTCN2017114074-appb-000005
为网侧交流电压参考值Uac_ref的标幺值，Uac_d为网侧电压d轴分量，Ti为积分时间常数；
以及，通过下式计算得到所述第一极调制电压q轴参考值Uq1_ref：
Figure PCTCN2017114074-appb-000006
式中，Uq1_ref为第一极调制电压q轴参考值，Kp为比例系数，Uac_q为网侧电压q轴分量，Ti为积分时间常数。
上述方案中，所述装置还包括：
双环控制单元，配置为对所述第二极VSC解锁后采用外环为功率环、内环为电流环的双环控制。
上述方案中，所述双环控制单元，还配置为对有功功率参考值与有功功率实测值的差进行PI控制，得到内环电流d轴参考值，对无功功率参考值与无功功率实测值的差进行PI控制，得到内环电流q轴参考值，所述内环电流d轴参考值和所述内环电流q轴参考值经过内环电流控制器，分别得到第二极调制电压d轴参考值和第二极调制电压q轴参考值，进行帕克反变换，得到第二极VSC的三相调制电压参考值。
本发明实施例还提供了一种计算机存储介质，所述计算机存储介质存储有计算机程序，该计算机程序配置为执行本发明实施例的上述双极VSC无源控制方法。
应用本发明实施例的双极VSC无源控制方法、装置及存储介质，具有以下有益效果：
通过控制逆变侧的其中一极VSC解锁后，对其采用定交流电压控制，然后控制逆变侧的另一极VSC对上述其中一极VSC输出的相位进行锁相，锁相后控制另一极VSC解锁。如此，实现了两极VSC的平稳解锁，解锁后两极VSC的电压相位保持同步，并同时为同一无源网络稳定供电。
附图说明
图1是本发明实施例提供的双极无源混合直流输电系统的拓扑结构示意图；
图2是本发明实施例提供的双极VSC中其中一极VSC的拓扑结构示意图；
图3是本发明实施例提供的双极VSC的极1控制器原理框图；
图4是本发明实施例提供的双极VSC的极2控制器原理框图；
图5是本发明实施例提供的双极VSC无源控制装置的组成结构示意 图。
具体实施方式
下文中将参考附图并结合实施例来详细说明本发明。需要说明的是，在不冲突的情况下，本申请中的实施例及实施例中的特征可以相互组合。
如图1所示的双极无源混合直流输电系统，整流侧采用LCC接入交流电网，逆变侧采用VSC接入无源网络，LCC端通过直流线路将功率送至VSC端，LCC端直流侧串有平波电抗器，VSC端直流侧串有二极管，VSC端采用MMC结构，换流器由三相6个桥臂构成，每个桥臂由桥臂电感和数量相同的子模块构成，如图2所示，子模块采用半桥结构，包含2个IGBT、2个反并联二极管和1个储能电容。
针对图1的混合直流系统，控制整流侧的双极LCC端解锁，利用双极LCC提供的稳定的直流电压，为逆变侧的极1和极2(将双极VSC中先解锁的一极VSC称为极1，后解锁的一极VSC称为极2)的子模块中的电容器进行充电，充电完成后，解锁VSC端极1，极1解锁后采用定交流电压控制，建立VSC端交流侧的三相电压。由于VSC端极1和极2连接在同一个无源网络中，所以此时VSC端极1解锁后，其交流侧已存在交流电压，控制极2对极1输出的电压相位进行锁相，将极2的电压相位与极1的电压相位进行同步，然后以定有功功率控制和定无功功率控制方式对极2进行解锁。VSC端极2解锁后，可通过控制极2输出的有功功率和无功功率值完成两极的功率分配，实现有功功率和无功功率的双极协调控制。
当VSC端通过直流侧无源充电完成后，对VSC端极1进行解锁采用定交流电压控制，该控制过程包括：
如图3所示，对网侧交流电压参考值Uac_ref的标幺值与网侧电压d轴分量Uac_d的差进行控制，得到第一极调制电压d轴参考值Ud1_ref，对0与网侧电压q轴分量Uac_q的差进行控制，得到第一极调制电压q轴参考值Uq1_ref， 然后进行帕克反变换，得到极1的三相调制电压参考值Ua1_ref、Ub1_ref、Uc1_ref。其中，Uac_ref从0以一定斜率增大，从而使建立的网侧交流电压平稳上升。
当VSC端极1解锁后，由于VSC端的两极连接在同一个无源网络中，所以此时VSC端极2的交流侧已存在交流电压，控制极2锁相极1的电压相位，然后以定有功功率控制和定无功功率控制方式对极2进行解锁，极2的控制过程为：
如图4所示，对有功功率参考值Pac_ref与有功功率实测值Pac_meas的差进行PI控制，得到内环电流d轴参考值Id_ref，对无功功率参考值Qac_ref与无功功率实测值Qac_meas的差进行PI控制，得到内环电流q轴参考值Iq_ref，经过内环电流控制器分别得到第二极调制电压d轴参考值Ud2_ref和第二极调制电压q轴参考值Uq2_ref，进行帕克反变换得到极2的三相调制电压参考值Ua2_ref、Ub2_ref、Uc2_ref。其中，Pac_ref和Qac_ref从0以一定的升降速率增大或减小，从而使输出的有功功率与无功功率平稳变化。
然后，通过改变VSC端极2的Pac_ref、Qac_ref和相应的升降速率参考值完成两极的功率分配，实现有功功率和无功功率的双极协调控制。运行过程中，若极2发生故障，则极2停运，极1继续运行；若极1发生故障，则极1停运，同时极2控制策略切换为定交流电压控制并继续运行。
在实际实施时，利用整流侧LCC端解锁后建立直流电压，通过直流线路给逆变侧VSC端的子模块进行无源充电，然后解锁VSC端极1，从而建立VSC端交流侧三相电压，并在VSC端极2的交流侧产生交流电压，最后使极2锁相极1的电压相位后，以定有功功率和定无功功率控制方式将极2解锁。VSC端极2解锁后，可通过控制极2输出的有功功率和无功功率值完成两极的功率分配，实现有功功率和无功功率的双极协调控制，逻辑简单，易于工程实现，能实现两极VSC的平稳解锁，同时为同一无源网络稳定供电。
需要说明的是，本发明实施例提供的上述直流输电系统的双极VSC无源控制方法不仅仅适用于如图1所示的双极无源混合直流输电系统，即整流侧的换流器不限于LCC，也可以是双极VSC或其他类型的换流器，只要整流侧的换流器能为逆变侧提供稳定的直流电压即可。
本实施例中解锁双极LCC的方式可以根据需要设定，既可以是同时解锁双极LCC为VSC端极1和极2的电容器充电，充电完成后再解锁极1和极2；也可以采用先解锁极1对端的LCC，再解锁极2对端LCC的方式，然后进行极1和极2的解锁；还可以在整流侧和逆变侧的两级进行分别解锁，如解锁极1对端的LCC后，解锁VSC端的极1，再解锁极2对端的LCC，最后解锁VSC端的极2。
本发明实施例还提供了一种双极VSC无源控制装置，图5为本发明实施例双极VSC无源控制装置的组成结构示意图，如图5所示，包括充电单元51和解锁控制单元52，
其中，充电单元51，配置为对逆变侧的第一极VSC和第二极VSC通过整流侧提供的直流电压进行无源充电；
解锁控制单元52，配置为控制逆变侧的第一极VSC解锁后，对所述第一极VSC采用定交流电压控制，得到第一极VSC的三相调制参考电压；控制逆变侧的第二极VSC对所述第一极VSC输出的三相交流电压的相位进行锁相，锁相后控制所述第二极VSC解锁。
在一实施例中，所述解锁控制单元52，还配置为对网侧交流电压参考值与网侧电压d轴分量的差进行相应的处理，得到第一极调制电压d轴参考值；
以及，对0与网侧电压q轴分量的差进行相应的处理，得到第一极调制电压q轴参考值，对所述第一极调制电压d轴参考值和第一极调制电压q轴参考值进行帕克反变换，得到第一极VSC的三相调制参考电压值。
在一实施例中，所述解锁控制单元52包括计算单元521，配置为通过下式计算得到所述第一极调制电压d轴参考值：
Figure PCTCN2017114074-appb-000007
式中，Ud1_ref为第一极调制电压d轴参考值，Kp为比例系数，
Figure PCTCN2017114074-appb-000008
为网侧交流电压参考值Uac_ref的标幺值，Uac_d为网侧电压d轴分量，Ti为积分时间常数；
以及，通过下式计算得到所述第一极调制电压q轴参考值Uq1_ref：
Figure PCTCN2017114074-appb-000009
式中，Uq1_ref为第一极调制电压q轴参考值，Kp为比例系数，Uac_q为网侧电压q轴分量，Ti为积分时间常数。
在一实施例中，所述装置还包括：
双环控制单元53，配置为对所述第二极VSC解锁后采用外环为功率环、内环为电流环的双环控制。
在一实施例中，所述双环控制单元53，还配置为对有功功率参考值与有功功率实测值的差进行PI控制，得到内环电流d轴参考值，对无功功率参考值与无功功率实测值的差进行PI控制，得到内环电流q轴参考值，所述内环电流d轴参考值和所述内环电流q轴参考值经过内环电流控制器，分别得到第二极调制电压d轴参考值和第二极调制电压q轴参考值，进行帕克反变换，得到第二极VSC的三相调制电压参考值。
上述实施例中所述的双极VSC无源控制装置，实际上是基于本发明方法流程的一种计算机解决方案，即一种软件构架，可以应用到换流站中，上述装置即为与方法流程相对应的处理进程。由于对上述方法的介绍已经足够清楚完整，且本实施例声称的装置实际上是一种软件构架，故不再详细进行描述。
本领域内的技术人员应明白，本发明的实施例可提供为方法、系统、或计算机程序产品。因此，本发明可采用硬件实施例、软件实施例、或结合软件和硬件方面的实施例的形式。而且，本发明可采用在一个或多个其中包含有计算机可用程序代码的计算机可用存储介质(包括但不限于磁盘存储器和光学存储器等)上实施的计算机程序产品的形式。
本发明是参照根据本发明实施例的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程和/或方框的结合。可提供这些计算机程序指令到通用计算机、专用计算机、嵌入式处理机或其他可编程数据处理设备的处理器以产生一个机器，使得通过计算机或其他可编程数据处理设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。
这些计算机程序指令也可存储在能引导计算机或其他可编程数据处理设备以特定方式工作的计算机可读存储器中，使得存储在该计算机可读存储器中的指令产生包括指令装置的制造品，该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能。
这些计算机程序指令也可装载到计算机或其他可编程数据处理设备上，使得在计算机或其他可编程设备上执行一系列操作步骤以产生计算机实现的处理，从而在计算机或其他可编程设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。
以上所述，仅为本发明的较佳实施例而已，并非用于限定本发明的保护范围。
工业实用性
本发明实施例中逆变侧的第一极VSC和第二极VSC通过整流侧提供的直流电压进行无源充电；控制逆变侧的第一极VSC解锁后，对所述第一极VSC采用定交流电压控制，得到第一极VSC的三相调制参考电压，从而建立网侧交流电压；控制逆变侧的第二极VSC对所述第一极VSC建立的网侧交流电压的相位进行锁相，锁相后控制所述第二极VSC解锁。如此，实现了两极VSC的平稳解锁，解锁后两极VSC的电压相位保持同步，并同时为同一无源网络稳定供电。

Claims (11)

  1. 一种双极电压源换流器VSC无源控制方法，包括：
    逆变侧的第一极VSC和第二极VSC通过整流侧提供的直流电压进行无源充电；
    控制逆变侧的第一极VSC解锁后，对所述第一极VSC采用定交流电压控制，得到第一极VSC的三相调制参考电压，从而建立网侧交流电压；控制逆变侧的第二极VSC对所述第一极VSC建立的网侧交流电压的相位进行锁相，锁相后控制所述第二极VSC解锁。
  2. 根据权利要求1所述的方法，其中，所述定交流电压控制包括：
    对网侧交流电压参考值与网侧电压d轴分量的差进行相应的处理，得到第一极调制电压d轴参考值；
    对0与网侧电压q轴分量的差进行相应的处理，得到第一极调制电压q轴参考值，对所述第一极调制电压d轴参考值和第一极调制电压q轴参考值进行帕克反变换，得到第一极VSC的三相调制参考电压值。
  3. 根据权利要求2所述的方法，其中，所述第一极调制电压d轴参考值通过下式计算得到：
    Figure PCTCN2017114074-appb-100001
    式中，Ud1_ref为第一极调制电压d轴参考值，Kp为比例系数，
    Figure PCTCN2017114074-appb-100002
    为网侧交流电压参考值Uac_ref的标幺值，Uac_d为网侧电压d轴分量，Ti为积分时间常数；
    所述第一极调制电压q轴参考值Uq1_ref通过下式计算得到：
    Figure PCTCN2017114074-appb-100003
    式中，Uq1_ref为第一极调制电压q轴参考值，Kp为比例系数，Uac_q为网 侧电压q轴分量，Ti为积分时间常数。
  4. 根据权利要求1所述的方法，其中，所述第二极VSC解锁后采用外环为功率环、内环为电流环的双环控制。
  5. 根据权利要求4所述的方法，其中，所述外环为功率环、内环为电流环的双环控制包括：对有功功率参考值与有功功率实测值的差进行比例和积分PI控制，得到内环电流d轴参考值，对无功功率参考值与无功功率实测值的差进行PI控制，得到内环电流q轴参考值，所述内环电流d轴参考值和所述内环电流q轴参考值经过内环电流控制器，分别得到第二极调制电压d轴参考值和第二极调制电压q轴参考值，进行帕克反变换，得到第二极VSC的三相调制电压参考值。
  6. 一种双极电压源换流器VSC无源控制装置，包括：
    充电单元，配置为通过整流侧提供的直流电压对逆变侧的第一极VSC和第二极VSC进行无源充电；
    解锁控制单元，配置为控制逆变侧的第一极VSC解锁后，对所述第一极VSC采用定交流电压控制，得到第一极VSC的三相调制参考电压，从而建立网侧交流电压；控制逆变侧的第二极VSC对所述第一极VSC建立的网侧交流电压的相位进行锁相，锁相后控制所述第二极VSC解锁。
  7. 根据权利要求6所述的装置，其中，
    所述解锁控制单元，还配置为对网侧交流电压参考值与网侧电压d轴分量的差进行相应的处理，得到第一极调制电压d轴参考值；
    以及，对0与网侧电压q轴分量的差进行相应的处理，得到第一极调制电压q轴参考值，对所述第一极调制电压d轴参考值和第一极调制电压q轴参考值进行帕克反变换，得到第一极VSC的三相调制参考电压值。
  8. 根据权利要求7所述的装置，其中，所述解锁控制单元包括计算单元，配置为通过下式计算得到所述第一极调制电压d轴参考值：
    Figure PCTCN2017114074-appb-100004
    式中，Ud1_ref为第一极调制电压d轴参考值，Kp为比例系数，
    Figure PCTCN2017114074-appb-100005
    为网侧交流电压参考值Uac_ref的标幺值，Uac_d为网侧电压d轴分量，Ti为积分时间常数；
    以及，通过下式计算得到所述第一极调制电压q轴参考值Uq1_ref：
    Figure PCTCN2017114074-appb-100006
    式中，Uq1_ref为第一极调制电压q轴参考值，Kp为比例系数，Uac_q为网侧电压q轴分量，Ti为积分时间常数。
  9. 根据权利要求6所述的装置，其中，所述装置还包括：
    双环控制单元，配置为对所述第二极VSC解锁后采用外环为功率环、内环为电流环的双环控制。
  10. 根据权利要求9所述的装置，其中，
    所述双环控制单元，还配置为对有功功率参考值与有功功率实测值的差进行PI控制，得到内环电流d轴参考值，对无功功率参考值与无功功率实测值的差进行PI控制，得到内环电流q轴参考值，所述内环电流d轴参考值和所述内环电流q轴参考值经过内环电流控制器，分别得到第二极调制电压d轴参考值和第二极调制电压q轴参考值，进行帕克反变换，得到第二极VSC的三相调制电压参考值。
  11. 一种计算机存储介质，所述计算机存储介质中存储有计算机可执行指令，该计算机可执行指令用于执行权利要求1至5任一项所述的双极电压源换流器VSC无源控制方法。
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CN107134800B (zh) * 2017-04-27 2019-12-24 许继电气股份有限公司 一种直流输电系统的双极vsc无源控制方法及装置
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104362662A (zh) * 2014-11-26 2015-02-18 湖北工业大学 一种lcc-vsc型混合直流输电系统拓扑结构及启动方法
CN104485683A (zh) * 2014-12-23 2015-04-01 南京南瑞继保电气有限公司 一种孤岛转联网方法
CN104821596A (zh) * 2015-05-21 2015-08-05 国家电网公司 一种基于内模控制的混合直流输电系统拓扑及控制方法
CN105429165A (zh) * 2015-12-23 2016-03-23 湖北工业大学 一种向多落点无源网络供电的多端混合直流输电系统拓扑及控制方法
US20160268916A1 (en) * 2015-03-11 2016-09-15 DRS Consolidated Controls, Inc. Reference current generation in bidirectional power converter
CN107134800A (zh) * 2017-04-27 2017-09-05 许继电气股份有限公司 一种直流输电系统的双极vsc无源控制方法及装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104362662A (zh) * 2014-11-26 2015-02-18 湖北工业大学 一种lcc-vsc型混合直流输电系统拓扑结构及启动方法
CN104485683A (zh) * 2014-12-23 2015-04-01 南京南瑞继保电气有限公司 一种孤岛转联网方法
US20160268916A1 (en) * 2015-03-11 2016-09-15 DRS Consolidated Controls, Inc. Reference current generation in bidirectional power converter
CN104821596A (zh) * 2015-05-21 2015-08-05 国家电网公司 一种基于内模控制的混合直流输电系统拓扑及控制方法
CN105429165A (zh) * 2015-12-23 2016-03-23 湖北工业大学 一种向多落点无源网络供电的多端混合直流输电系统拓扑及控制方法
CN107134800A (zh) * 2017-04-27 2017-09-05 许继电气股份有限公司 一种直流输电系统的双极vsc无源控制方法及装置

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