CN110867884B - 耗能模块、海上风电经柔性直流外送系统及故障穿越策略 - Google Patents

耗能模块、海上风电经柔性直流外送系统及故障穿越策略 Download PDF

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CN110867884B
CN110867884B CN201911129322.5A CN201911129322A CN110867884B CN 110867884 B CN110867884 B CN 110867884B CN 201911129322 A CN201911129322 A CN 201911129322A CN 110867884 B CN110867884 B CN 110867884B
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苏匀
李少华
姚东晓
马小婷
沈开奎
蒋大海
马松江
涂小刚
李孝维
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Xi'an Duanyi Technology Co ltd
China XD Electric Co Ltd
Xian XD Power Systems Co Ltd
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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
    • H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/483—Converters with outputs that each can have more than two voltages levels
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/483—Converters with outputs that each can have more than two voltages levels
    • H02M7/4835—Converters with outputs that each can have more than two voltages levels comprising two or more cells, each including a switchable capacitor, the capacitors having a nominal charge voltage which corresponds to a given fraction of the input voltage, and the capacitors being selectively connected in series to determine the instantaneous output voltage
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/0003—Details of control, feedback or regulation circuits
    • H02M1/0038—Circuits or arrangements for suppressing, e.g. by masking incorrect turn-on or turn-off signals, e.g. due to current spikes in current mode control
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/0048—Circuits or arrangements for reducing losses
    • H02M1/0054—Transistor switching losses
    • 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
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
    • 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
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/70—Wind energy
    • Y02E10/76—Power conversion electric or electronic aspects
    • 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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Abstract

本发明公开了一种耗能模块、海上风电经柔性直流外送系统及故障穿越策略，应用于海上风电经柔性直流外送的系统中，直流斩波耗能模块集成于陆上换流站的MMC内部。DC Chopper采用模块化布置且与MMC的SM子模块串联在一起，DC Chopper模块中不含电容组件。当海上风电柔性直流送出系统中发生陆上站交流故障时，直流电压会急剧升高，投入一定数量的耗能模块DM，通过耗能电阻消耗盈余功率，维持系统短时稳定，待故障恢复后，退出对应耗能模块DM，完成系统的故障穿越。通过将DC Chopper模块化布置，且正常运行时处于旁路状态，不但能够实现盈余功率的精确匹配，大幅减小斩波装置投切过程的电气量波动，实现了故障穿越与隔离，而且耗能模块DM组件结构简单，经济性较好。

Description

耗能模块、海上风电经柔性直流外送系统及故障穿越策略
技术领域
本发明属于海上风电经柔性直流输电外送陆上交流系统技术领域，具体涉及一种新型的直流斩波(DC Chopper)耗能方案及其故障穿越策略。
背景技术
当海上风电经柔性直流输电送电陆上交流系统时，由于柔性直流输电系统尤其是MMC换流器技术的应用，可以有效地隔离海上风电系统的故障，防止海上孤立风电系统的故障波及陆上交流系统。但是，当陆上交流系统发生故障，导致海上风电系统的电力外送受阻，过多的能量无法送出将使直流系统产生严重的过电压，甚至会引起海上风电系统的停运，风机切机，也即陆上交流系统故障会传递至海上风电系统上。为了避免这种情况发生，阻断陆上交流系统的故障传播，通常需要在陆上换流站侧装设直流斩波DC Chopper电路来消耗此过剩的能量。DC Chopper可以采用模块化布置，也可集中式布置。前者的du/dt和di/dt变化率小，可实现平滑可控放电，但成本较高，而后者的成本较低，经济性较好，但du/dt和di/dt变化率大。
发明内容
为了解决上述问题，本发明提供了一种耗能模块、海上风电经柔性直流外送系统及故障穿越策略，可有效提升海上风电柔性直流输电系统动态性能及经济性。
为达到上述目的，本发明所述一种用于直流斩波的耗能模块，包括全控型器件、二极管D、旁路开关K和耗能电阻R，所述全控型器件、二极管D、旁路开关K和耗能电阻R四者并联，所述耗能模块不含电容，从与其相邻的SM子模块取能。
进一步的，全控型器件为IGBT。
一种海上风电经柔性直流外送系统，包括海上风电场，海上风电场的电能依次经过模块化多电平换流器、直流电缆和含集成斩波器的MMC输送至陆上交流系统；其中，含集成斩波器的MMC中集成有上的耗能模块。
进一步的，含集成斩波器的MMC包括三相6个桥臂，每个桥臂由n个结构相同的SM子模块级联，并串联n个上述的耗能模块，再与一个桥臂电感L0串联而成，同相的上、下两个桥臂构成一个相单元。
进一步的，当耗能模块正常运行时，全控型器件处于开通状态，旁路开关K处于分离状态，此时耗能电阻R被旁路；当全控型器件失效时，旁路开关K闭合，以将故障的耗能模块旁路。
一种基于上述的海上风电经柔性直流外送系统的故障穿越策略，当陆上换流站发生交流故障，导致陆上换流器直流极线间的电势高于预设的过压门限时，关断部分耗能模块中的全控型器件，并旁路部分SM子模块，将直流回路上的电流导入至耗能模块中的耗能电阻R上，将能量泄放至各个耗能模块的耗能电阻R上；当直流侧系统电压恢复至正常值，且陆上交流系统恢复时，将耗能模块退出运行，实现故障穿越。
与现有技术相比，本发明至少具有以下有益的技术效果：
本发明解决海上风电经柔性直流输电外送电力领域，当陆上站发生交流故障时，耗能模块DM能消耗盈余能量，避免故障扩散到海上系统，DC Choppe集成在原MMC换流器中，不改变原柔性直流输电系统的基本主回路拓扑结构，耗能模块DM结构简单，且不含电容模块，它向相邻的SM子模块取能，经济性较好。通过将DC Chopper模块化布置，且正常运行时处于旁路状态，不但能够实现盈余功率的精确匹配，大幅减小斩波装置投切过程的电气量波动，实现了故障穿越与隔离，而且DM组件结构简单，经济性较好。
一种新型的直流斩波耗能方案，耗能模块DM没有储能电容，每个模块都独立可控，进而使泄能支路的端间电压可控，避免出现电压波动大的情况，能够消除大du/dt和di/dt，保护输电设备，保障通讯；正常运行时，所有耗能模块DM模块都处于旁路状态，损耗很小。此外，每个DM模块都设置有旁路开关，防止模块拒动故障，整体可用率极高。
附图说明
图1为海上风电经柔性直流外送应用场景电气接线示意图；
图2为标准化耗能模块DM拓扑及在MMC换流器中的布置图。
具体实施方式
下面结合附图和具体实施方式对本发明进行详细说明。
参见图1，本发明的一种新型的直流斩波耗能方案及其故障穿越策略，包括风电场及其附属设备、海上换流站和陆上换流站，陆上换流站的MMC内部集成分布式直流斩波器DCChopper。海上风电场送出电能依次经过海上换流站、直流电缆、陆上换流站送入至陆上交流系统。
柔性直流输电系统可以采用对称单极接线方式，也可以采用对称双极接线方式。模块化直流耗能装置集成于模块化多电平换流器(MMC)中。在每个DM子模块内部含有一个耗能电阻R，将柔性直流输电系统所需要的耗能功率平均分配到每个DM子模块中。
参照图2，MMC及DM模块的基本拓扑结构如图2所示，它由三相6个桥臂组成，每个桥臂由若干个结构相同的SM子模块级联，并串联若干个结构相同的DM模块，然后再与一个桥臂电感L0串联而成，同相的上、下两个桥臂构成一个相单元。SM子模块可以是半桥子模块、全桥子模块或者二者的混合。
一种新型的直流斩波方案及其故障穿越策略，包括若干串联的耗能模块DM(DCChopper Module)，所述耗能模块DM包括IGBT、二极管D、旁路开关K和耗能电阻R。所述的IGBT、二极管、耗能电阻及旁路开关四者并联。其中，耗能模块DM中不含电容组件，且若干个DM与换流器子模块SM串联在同一桥臂中，DM模块从与之相邻的SM模块取能。
本发明应用于海上风电经柔性直流外送系统中，DC Chopper电路布置陆上换流站中且与MMC换流器集成在一起。耗能模块DM正常运行时，IGBT处于开通状态，旁路开关K处于分离状态，此时耗能电阻R被旁路。当耗能模块DM中的IGBT失效时，合上快速旁路开关K把该故障DM旁路。
当陆上换流站发生交流故障时，造成陆上站功率送出受阻，从而导致直流侧系统电压升高，当陆上换流器直流端间的电势高于预设的过压门限时，关断部分耗能模块DM的IGBT，并旁路部分SM子模块，将直流回路上的电流导入至耗能电阻R上，将能量泄放至各个DM模块的耗能电阻R上，通过耗能电阻消耗盈余功率，维持系统短时稳定；直流侧系统电压恢复至正常值后，且当陆上交流系统恢复时，耗能模块DM退出运行，转入旁路模式，实现故障穿越。
本发明通过电力系统电磁暂态专业仿真工具PSCAD/EMTDC来编写程序、调试及验证。本策略适合海上风电经柔性直流外送的应用场景，其控制策略简单易用，可以在陆上交流系统故障的暂态过程中抑制直流系统的过电压，具有极大的工程实用价值。

Claims (2)

1.一种海上风电经柔性直流外送系统，其特征在于，包括海上风电场，所述海上风电场的电能依次经过模块化多电平换流器、直流电缆和含集成斩波器的MMC输送至陆上交流系统；其中，含集成斩波器的MMC中集成有耗能模块，所述耗能模块包括全控型器件、二极管D、旁路开关K和耗能电阻R，所述全控型器件、二极管D、旁路开关K和耗能电阻R四者并联，所述耗能模块不含电容，从与其相邻的SM子模块取能；
所述含集成斩波器的MMC包括三相6个桥臂，每个桥臂由n个结构相同的SM子模块级联，并串联n个耗能模块，SM与DM交叉级联，再与一个桥臂电感L0串联而成，同相的上、下两个桥臂构成一个相单元；
当所述耗能模块正常运行时，全控型器件处于开通状态，旁路开关K处于分离状态，此时耗能电阻R被旁路；当全控型器件失效时，旁路开关K闭合，以将故障的耗能模块旁路。
2.一种基于权利要求1所述的海上风电经柔性直流外送系统的故障穿越策略，其特征在于，当陆上换流站发生交流故障，导致陆上换流器直流极线间的电势高于预设的过压门限时，关断部分耗能模块中的全控型器件，并旁路部分SM子模块，将直流回路上的电流导入至耗能模块中的耗能电阻R上，将能量泄放至各个耗能模块的耗能电阻R上；当直流侧系统电压恢复至正常值，且陆上交流系统恢复时，将耗能模块退出运行，实现故障穿越。
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CN113671367B (zh) * 2021-08-30 2023-03-14 华北电力大学 换流阀故障自穿越等效试验方法及其应用
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CN117134402A (zh) * 2022-05-20 2023-11-28 南京南瑞继保电气有限公司 直流输电系统用的耗储一体换流器及其控制方法
CN115173456B (zh) * 2022-05-23 2024-10-01 中国电力工程顾问集团中南电力设计院有限公司 一种海上柔性直流海缆永久性故障穿越方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012231624A (ja) * 2011-04-27 2012-11-22 Fuji Electric Co Ltd 風力発電用電力変換装置
CN108767890A (zh) * 2018-08-15 2018-11-06 中国电建集团华东勘测设计研究院有限公司 具有耗能直流斩波器的海上风电柔性直流输电系统及其故障穿越方法
CN109586334A (zh) * 2018-11-07 2019-04-05 詹长江 一种集成耗能电路功能的换流器
CN109873441A (zh) * 2019-03-29 2019-06-11 西安许继电力电子技术有限公司 一种具有分布式直流耗能装置的风电柔性直流送出系统

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012231624A (ja) * 2011-04-27 2012-11-22 Fuji Electric Co Ltd 風力発電用電力変換装置
CN108767890A (zh) * 2018-08-15 2018-11-06 中国电建集团华东勘测设计研究院有限公司 具有耗能直流斩波器的海上风电柔性直流输电系统及其故障穿越方法
CN109586334A (zh) * 2018-11-07 2019-04-05 詹长江 一种集成耗能电路功能的换流器
CN109873441A (zh) * 2019-03-29 2019-06-11 西安许继电力电子技术有限公司 一种具有分布式直流耗能装置的风电柔性直流送出系统

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