CN115085521A - 一种基于六边形变流器的风机并网***闭环预充电控制方法 - Google Patents

一种基于六边形变流器的风机并网***闭环预充电控制方法 Download PDF

Info

Publication number
CN115085521A
CN115085521A CN202210630915.5A CN202210630915A CN115085521A CN 115085521 A CN115085521 A CN 115085521A CN 202210630915 A CN202210630915 A CN 202210630915A CN 115085521 A CN115085521 A CN 115085521A
Authority
CN
China
Prior art keywords
ref
contactor
bridge
hexagonal
full
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210630915.5A
Other languages
English (en)
Inventor
荣飞
徐爽
潘烙
黄春辉
黄守道
孙克强
黄泰霖
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hunan University
Original Assignee
Hunan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hunan University filed Critical Hunan University
Priority to CN202210630915.5A priority Critical patent/CN115085521A/zh
Publication of CN115085521A publication Critical patent/CN115085521A/zh
Pending legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/381Dispersed generators
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M1/00Details of apparatus for conversion
    • H02M1/0067Converter structures employing plural converter units, other than for parallel operation of the units on a single load
    • H02M1/007Plural converter units in cascade
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M1/00Details of apparatus for conversion
    • H02M1/32Means for protecting converters other than automatic disconnection
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M5/00Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
    • H02M5/04Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
    • H02M5/22Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M5/275Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M5/293Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M5/00Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
    • H02M5/04Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
    • H02M5/22Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M5/275Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M5/293Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M5/2932Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage, current or power
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2300/00Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
    • H02J2300/20The dispersed energy generation being of renewable origin
    • H02J2300/28The renewable source being wind energy
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/70Wind energy
    • Y02E10/76Power conversion electric or electronic aspects

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Rectifiers (AREA)

Abstract

本发明公开了一种基于六边形变流器的风机并网***闭环预充电控制方法。该风机并网***包括:风力机、六边形变流器、直驱永磁同步发电机、接触器KM1、接触器KM2、限流电阻R1、限流电阻R2、限流电阻R3和交流电网;闭环预充电控制方法由不控充电阶段和闭环可控充电阶段组成,根据变流器容量自行设定可控充电阶段的充电功率,由充电功率计算桥臂电流参考值,采用准PR控制器对桥臂电流参考值进行跟踪并得到桥臂电压调制波,采用均压控制得到全桥子模块的调制波叠加量,桥臂电压调制波与全桥子模块的调制波叠加量相加得到全桥子模块的调制波,采用载波移相调制得到全桥子模块的开关信号,当全桥子模块电容电压平均值达到额定值,可控充电完成;本发明给出了基于六边形变流器的风机并网***预充电拓扑结构,闭环预充电控制方法具有恒流充电,无浪涌电流;充电时间可控;控制简单,无需额外增加控制器的优点。

Description

一种基于六边形变流器的风机并网***闭环预充电控制方法
技术领域
本发明属于AC/AC变流器预充电领域,特别涉及一种基于六边形变流器的风机并网***闭环预充电控制方法。
背景技术
2020年9月,中国明确提出“双碳”目标,这是一项对全中国乃至全人类都意义深远的国策;因此,推动能源转型、建立以绿色清洁能源为主的新型电力***势在必行。
我国幅员辽阔、海岸线丰富,在三北(东北、华北、西北)地区以及沿海地带都有着优质的风能资源。风电作为一种可持续发展的绿色清洁能源,研究如何实现风电稳定、高效的并网逐渐成为研究热点。
在传统的风电并网结构中多采用交直交形式,风机发出的电通常需经两级变换以及升压变升压后才能实现并网,两级变流器以及升压变的使用增加了***损耗;六边形变流器是一种直接AC/AC的变流器,可实现风电经一级变换后直接并网,无需体积庞大且笨重的升压变,并且低频特性好,在风力风电领域应用前景广阔。
六边形变流器在稳定运行前必须将所有全桥子模块电容电压充电至其额定值,否则一旦强行启动会产生过电流造成器件损坏,严重时还会造成***崩坏。然而由于六边形变流器子模块电容分散,且个数众多,给六边形变流器预充电带来了困难。目前并未有针对六边形变流器的预充电方法,已有的预充电方法主要集中在模块化多电平变换器(MMC)以及模块化多电平变换器(MMMC);其中以开环形式的分组预充电居多,这种方法充电时间较长,不适用于对启动时间有限制的场合;少数针对采取半桥结构MMC提出的闭环预充电方法的确可以实现充电电流可控,但是需要额外设计预充电控制器,增加了成本。
发明内容
针对上述背景技术描述的缺点和不足,本发明提出了一种基于六边形变流器的风机并网***闭环预充电控制方法,具有无浪涌充电电流、充电时间可控、子模块一致性好和无需额外增加预充电控制器的优点。
本发明所提供的技术方案如下:
一种基于六边形变流器的风机并网***闭环预充电控制方法,其特征在于所述的基于六边形变流器的风机并网***由风力机、六边形变流器、直驱永磁同步发电机、接触器KM1、接触器KM2、限流电阻R1、限流电阻R2、限流电阻R3和交流电网组成;
所述的六边形变流器由6个相同的桥臂,依次首尾相连形成一个六边形;每个桥臂由级联的m个全桥子模块和一个交流电抗器串联构成;交流电抗器记为Larm_k,k=1,2,3,4,5,6,表示第k个桥臂;全桥子模块记为SMk_j,下标j=1,2,…m,表示第j个全桥子模块;每个全桥子模块由4个带有反并联续流二极管的IGBT S1、S2、S3、S4和1个直流悬浮电容C组成;S1、S3的集电极以及直流悬浮电容C的正极相连接构成全桥子模块的正极;S2、S4的发射极以及直流悬浮电容C的负极相连接构成全桥子模块的负极;全桥子模块的正端口由S1的发射极和S2的集电极的连接点构成,全桥子模块的负端口由S3的发射极和S4的集电极的连接点构成;
接触器KM1的L1端口和交流电网的U相相连,接触器KM1的T1端口和六边形变流器的o1点相连;接触器KM1的L2端口和交流电网的V相相连,接触器KM1的T2端口和六边形变流器的o5点相连;接触器KM1的L3端口和交流电网的W相相连,接触器KM1的T3端口和六边形变流器的o3点相连;
限流电阻R1的一端和接触器KM1的L1端口相连,限流电阻R1的另一端和接触器KM1的T1端口相连;限流电阻R2的一端和接触器KM1的L2端口相连,限流电阻R2的另一端和接触器KM1的T2端口相连;限流电阻R3的一端和接触器KM1的L3端口相连,限流电阻R3的另一端和接触器KM1的T3端口相连;
风力机的转轴与直驱永磁同步发电机的转子同轴相连,直驱永磁同步发电机定子的三个绕组依次记为A、B、C三相;
接触器KM2的L1端口和直驱永磁同步发电机的定子A相相连,接触器KM2的T1端口和六边形变流器的o6点相连;接触器KM2的L2端口和直驱永磁同步发电机的定子B相相连,接触器KM2的T2端口和六边形变流器的o2点相连;接触器KM2的L3端口和直驱永磁同步发电机的定子C相相连,接触器KM2的T3端口和六边形变流器的o4点相连;
六边形变流器o6点和o1点之间的桥臂记为桥臂1,六边形变流器o1点和o2点之间的桥臂记为桥臂2,六边形变流器o2点和o3点之间的桥臂记为桥臂3,六边形变流器o3点和o4点之间的桥臂记为桥臂4,六边形变流器o4点和o5点之间的桥臂记为桥臂5,六边形变流器o5点和o6点之间的桥臂记为桥臂6;
所述的一种基于六边形变流器的风机并网***闭环预充电控制方法由不控充电阶段和闭环可控充电阶段组成;
所述的不控充电阶段由如下步骤组成:
(1)断开接触器KM2、断开接触器KM1,封锁IGBT开关信号,交流电网经限流电阻对六边形变流器进行不控充电;
(2)计算不控充电阶段六边形变流器全桥子模块电容电压的目标值U1
U1=0.93*sqrt(3)×Ug/2/m
其中sqrt()表示开平方函数,Ug是交流电网相电压的幅值;
(3)实时检测六边形变流器全桥子模块电容电压,并计算六边形变流器全桥子模块电容电压平均值Uave,当Uave大于等于目标值U1时,不控充电阶段结束;
所述的闭环可控充电阶段由如下步骤组成:
(1)闭合接触器KM1
(2)取电网q轴电流参考值igq_ref=0,计算电网d轴电流参考值igd_ref
igd_ref=2×P/3/Ug
其中P是交流电网传输的功率,可自行设定;
(3)对igd_ref、igq_ref=0采用dq/abc坐标变换,得到交流电网的三相电流参考值:igu_ref、igv_ref和igw_ref
(4)将igu_ref、igv_ref和igw_ref带入下式,计算桥臂k的电流参考值ik_ref
i1_ref=i6_ref=1/3×(igu_ref-igv_ref)
i2_ref=i3_ref=1/3×(igw_ref-igu_ref)
i4_ref=i5_ref=1/3×(igv_ref-igw_ref)
(5)采样各个桥臂的电流实际值ik,将ik_ref与ik作差带入准PR调节器得到桥臂k的调制波Uk_ref
Uk_ref=(ik_ref–ik)×(Kp1+Ksc1×s/(s2+2×ωsc1×s+(100π)2))
其中Kp1是第一准PR调节器的比例系数,Ksc1、ωsc1分别是第一准PR调节器的谐振系数和截止角频率;
(6)计算桥臂k的子模块电容电压平均值Uk_ave
Uk_ave=1/m×(Uk1+Uk2+…+Uk6)
其中Ukj为桥臂k的第j个子模块的电容电压采样值;
(7)将Ukj分别与Uk_ave做差带入P调节器后,P调节器输出与ik相乘得到桥臂k的第j个子模块的调制波叠加量Ukj_add
Ukj_add=(Ukj-Uk_ave)×ik×Kp2
其中Kp2是第一P调节器的比例系数;
(8)将Uk_ref和Ukj_add叠加得到桥臂k第j个子模块的调制波Ukj_ref
Ukj_ref=Uk_ref+Ukj_add
(9)将调制波Ukj_ref采用载波移相调制得到全桥子模块IGBT的开关信号;
(10)实时将Uave与全桥子模块电容电压参考值Uc_ref进行比较,当Uave大于等于Uc_ref时,可控充电阶段结束;闭合接触器KM2,风机接入***,执行基于六边形变流器的风机并网控制;
本发明的有益效果是:1)给出了基于六边形变流器的风机并网***预充电拓扑结构,针对该结构提出一种交流侧闭环预充电的控制方法,可以实现变流器充电电流为恒定值,无浪涌电流;2)充电功率可根据器件容量自行设定,当充电功率确定时即可计算出充电时间,因此可满足对一些有着故障快恢复要求的应用场合;3)控制简单,仅需采用准PR控制器即可实现闭环预充电,并且该控制器在风机并网运行时也投入工作,并未额外增加控制器。
附图说明
图1为基于六边形变流器的风机并网***预充电结构图;
图2为基于六边形变流器的风机并网***闭环预充电控制框图;
图3为六边形变流器桥臂1的电流波形;
图4为全桥子模块电容电压波形。
具体实施方式
为了使本发明所解决的技术问题、技术方案及有益效果更加清楚明白,以下结合附图对本发明进行进一步详细说明。应当理解,此处所描述的具体实例仅仅用以解释本发明,并不用于限定本发明。
图1是基于六边形变流器的风机并网***预充电结构图,本发明中风机并网***由风力机、六边形变流器、直驱永磁同步发电机、接触器KM1、接触器KM2、限流电阻R1、限流电阻R2、限流电阻R3和交流电网组成;六边形变流器由6个相同的桥臂,依次首尾相连形成一个六边形;每个桥臂由级联的m个全桥子模块和一个交流电抗器串联构成;交流电抗器记为Larm_k,k=1,2,3,4,5,6,表示第k个桥臂;全桥子模块记为SMk_j,下标j=1,2,…m,表示第j个全桥子模块;每个全桥子模块由4个带有反并联续流二极管的IGBT S1、S2、S3、S4和1个直流悬浮电容C组成;S1、S3的集电极以及直流悬浮电容C的正极相连接构成全桥子模块的正极;S2、S4的发射极以及直流悬浮电容C的负极相连接构成全桥子模块的负极;全桥子模块的正端口由S1的发射极和S2的集电极的连接点构成,全桥子模块的负端口由S3的发射极和S4的集电极的连接点构成;接触器KM1的L1端口和交流电网的U相相连,接触器KM1的T1端口和六边形变流器的o1点相连;接触器KM1的L2端口和交流电网的V相相连,接触器KM1的T2端口和六边形变流器的o5点相连;接触器KM1的L3端口和交流电网的W相相连,接触器KM1的T3端口和六边形变流器的o3点相连;限流电阻R1的一端和接触器KM1的L1端口相连,限流电阻R1的另一端和接触器KM1的T1端口相连;限流电阻R2的一端和接触器KM1的L2端口相连,限流电阻R2的另一端和接触器KM1的T2端口相连;限流电阻R3的一端和接触器KM1的L3端口相连,限流电阻R3的另一端和接触器KM1的T3端口相连;风力机的转轴与直驱永磁同步发电机的转子同轴相连,直驱永磁同步发电机定子的三个绕组依次记为A、B、C三相;接触器KM2的L1端口和直驱永磁同步发电机的定子A相相连,接触器KM2的T1端口和六边形变流器的o6点相连;接触器KM2的L2端口和直驱永磁同步发电机的定子B相相连,接触器KM2的T2端口和六边形变流器的o2点相连;接触器KM2的L3端口和直驱永磁同步发电机的定子C相相连,接触器KM2的T3端口和六边形变流器的o4点相连;六边形变流器o6点和o1点之间的桥臂记为桥臂1,六边形变流器o1点和o2点之间的桥臂记为桥臂2,六边形变流器o2点和o3点之间的桥臂记为桥臂3,六边形变流器o3点和o4点之间的桥臂记为桥臂4,六边形变流器o4点和o5点之间的桥臂记为桥臂5,六边形变流器o5点和o6点之间的桥臂记为桥臂6。
在本实例中,交流电网相电压额定值Ug为8165V,直流悬浮电容C大小为20mF,六边形变流器桥臂全桥子模块个数m为6,全桥子模块电容电压额定值Uc_ref为2500V,交流电抗器Larm_k为10mH,交流电网传输的功率P=3MW,控制周期T为0.0002s;R1=20,R2=20,R3=20。
图2是基于六边形变流器的风机并网***闭环预充电控制框图,控制方法由不控充电阶段和闭环可控充电阶段组成;
所述的不控充电阶段由如下步骤组成:
(1)断开接触器KM2、断开接触器KM1,封锁IGBT开关信号,交流电网经限流电阻对六边形变流器进行不控充电;
(2)计算不控充电阶段六边形变流器全桥子模块电容电压的目标值U1
U1=0.93*sqrt(3)×Ug/2/m
其中sqrt()表示开平方函数,Ug是交流电网相电压的幅值;
(3)实时检测六边形变流器全桥子模块电容电压,并计算六边形变流器全桥子模块电容电压平均值Uave,当Uave大于等于目标值U1时,不控充电阶段结束;
所述的闭环可控充电阶段由如下步骤组成:
(1)闭合接触器KM1
(2)取电网q轴电流参考值igq_ref=0,计算电网d轴电流参考值igd_ref
igd_ref=2×P/3/Ug
其中P是交流电网传输的功率,可自行设定;
(3)对igd_ref、igq_ref=0采用dq/abc坐标变换,得到交流电网的三相电流参考值:igu_ref、igv_ref和igw_ref
(4)将igu_ref、igv_ref和igw_ref带入下式,计算桥臂k的电流参考值ik_ref
i1_ref=i6_ref=1/3×(igu_ref-igv_ref)
i2_ref=i3_ref=1/3×(igw_ref-igu_ref)
i4_ref=i5_ref=1/3×(igv_ref-igw_ref)
(5)采样各个桥臂的电流实际值ik,将ik_ref与ik作差带入准PR调节器得到桥臂k的调制波Uk_ref
Uk_ref=(ik_ref–ik)×(Kp1+Ksc1×s/(s2+2×ωsc1×s+(100π)2))
其中Kp1是第一准PR调节器的比例系数,Ksc1、ωsc1分别是第一准PR调节器的谐振系数和截止角频率;
(6)计算桥臂k的子模块电容电压平均值Uk_ave
Uk_ave=1/m×(Uk1+Uk2+…+Uk6)
其中Ukj为桥臂k的第j个子模块的电容电压采样值;
(7)将Ukj分别与Uk_ave做差带入P调节器后,P调节器输出与ik相乘得到桥臂k的第j个子模块的调制波叠加量Ukj_add
Ukj_add=(Ukj-Uk_ave)×ik×Kp2
其中Kp2是第一P调节器的比例系数;
(8)将Uk_ref和Ukj_add叠加得到桥臂k第j个子模块的调制波Ukj_ref
Ukj_ref=Uk_ref+Ukj_add
(9)将调制波Ukj_ref采用载波移相调制得到全桥子模块IGBT的开关信号;
(10)实时将Uave与全桥子模块电容电压参考值Uc_ref进行比较,当Uave大于等于Uc_ref时,可控充电阶段结束;闭合接触器KM2,风机接入***,执行基于六边形变流器的风机并网控制;
上述步骤中,Kp1=90、Ksc1=1.2、ωsc1=6rad/s;Kp2=0.1。
图3为六边形变流器桥臂1的电流波形,在0s到1s处于不控充电阶段,充电电流在充电开始阶段达到最大后,随着子模块电容电压的增大逐渐减小;由于限流电阻的作用,不控充电的充电电流小于六边形变流器额定电流;在1s到1.6s处于可控充电阶段,充电电流的幅值为141A,除了在可控充电阶段刚开始有轻微的超调外,之后跟踪参考电流效果较好,实现了恒流充电。1.6s到2.5s处于风机并网额定运行工况。
图4为子模块电容电压波形,以桥臂1的第一个全桥子模块电容电压U11和桥臂2的第一个全桥子模块电容电压U21为例,不控充电阶段在1s时将子模块电压充至1096V转为可控充电,在可控充电阶段子模块电容电压基本按照固定的斜率上升至额定值2500V,这也与图3中恒流充电相对应,由于交流电网提供的充电功率P为3MW,基于能量守恒定理计算出的充电时间理论值和实际值0.6s也基本相符,***在1.6s全桥子模块电容电压充电至额定值时转为风机并网额定运行工况。

Claims (2)

1.一种基于六边形变流器的风机并网***闭环预充电控制方法,其特征在于所述的基于六边形变流器的风机并网***由风力机、六边形变流器、直驱永磁同步发电机、接触器KM1、接触器KM2、限流电阻R1、限流电阻R2、限流电阻R3和交流电网组成;
所述的六边形变流器由6个相同的桥臂,依次首尾相连形成一个六边形;每个桥臂由级联的m个全桥子模块和一个交流电抗器串联构成;交流电抗器记为Larm_k,k=1,2,3,4,5,6,表示第k个桥臂;全桥子模块记为SMk_j,下标j=1,2,…m,表示第j个全桥子模块;每个全桥子模块由4个带有反并联续流二极管的IGBT S1、S2、S3、S4和1个直流悬浮电容C组成;S1、S3的集电极以及直流悬浮电容C的正极相连接构成全桥子模块的正极;S2、S4的发射极以及直流悬浮电容C的负极相连接构成全桥子模块的负极;全桥子模块的正端口由S1的发射极和S2的集电极的连接点构成,全桥子模块的负端口由S3的发射极和S4的集电极的连接点构成;
接触器KM1的L1端口和交流电网的U相相连,接触器KM1的T1端口和六边形变流器的o1点相连;接触器KM1的L2端口和交流电网的V相相连,接触器KM1的T2端口和六边形变流器的o5点相连;接触器KM1的L3端口和交流电网的W相相连,接触器KM1的T3端口和六边形变流器的o3点相连;
限流电阻R1的一端和接触器KM1的L1端口相连,限流电阻R1的另一端和接触器KM1的T1端口相连;限流电阻R2的一端和接触器KM1的L2端口相连,限流电阻R2的另一端和接触器KM1的T2端口相连;限流电阻R3的一端和接触器KM1的L3端口相连,限流电阻R3的另一端和接触器KM1的T3端口相连;
风力机的转轴与直驱永磁同步发电机的转子同轴相连,直驱永磁同步发电机定子的三个绕组依次记为A、B、C三相;
接触器KM2的L1端口和直驱永磁同步发电机的定子A相相连,接触器KM2的T1端口和六边形变流器的o6点相连;接触器KM2的L2端口和直驱永磁同步发电机的定子B相相连,接触器KM2的T2端口和六边形变流器的o2点相连;接触器KM2的L3端口和直驱永磁同步发电机的定子C相相连,接触器KM2的T3端口和六边形变流器的o4点相连;
六边形变流器o6点和o1点之间的桥臂记为桥臂1,六边形变流器o1点和o2点之间的桥臂记为桥臂2,六边形变流器o2点和o3点之间的桥臂记为桥臂3,六边形变流器o3点和o4点之间的桥臂记为桥臂4,六边形变流器o4点和o5点之间的桥臂记为桥臂5,六边形变流器o5点和o6点之间的桥臂记为桥臂6;
所述的一种基于六边形变流器的风机并网***闭环预充电控制方法由不控充电阶段和闭环可控充电阶段组成;
所述的不控充电阶段由如下步骤组成:
(1)断开接触器KM2、断开接触器KM1,封锁IGBT开关信号,交流电网经限流电阻对六边形变流器进行不控充电;
(2)计算不控充电阶段六边形变流器全桥子模块电容电压的目标值U1
U1=0.93*sqrt(3)×Ug/2/m
其中sqrt()表示开平方函数,Ug是交流电网相电压的幅值;
(3)实时检测六边形变流器全桥子模块电容电压,并计算六边形变流器全桥子模块电容电压平均值Uave,当Uave大于等于目标值U1时,不控充电阶段结束;
所述的闭环可控充电阶段由如下步骤组成:
(1)闭合接触器KM1
(2)取电网q轴电流参考值igq_ref=0,计算电网d轴电流参考值igd_ref
igd_ref=2×P/3/Ug
其中P是交流电网传输的功率,可自行设定;
(3)对igd_ref、igq_ref=0采用dq/abc坐标变换,得到交流电网的三相电流参考值:igu_ref、igv_ref和igw_ref
(4)将igu_ref、igv_ref和igw_ref带入下式,计算桥臂k的电流参考值ik_ref
i1_ref=i6_ref=1/3×(igu_ref-igv_ref)
i2_ref=i3_ref=1/3×(igw_ref-igu_ref)
i4_ref=i5_ref=1/3×(igv_ref-igw_ref)
(5)采样各个桥臂的电流实际值ik,将ik_ref与ik作差带入准PR调节器得到桥臂k的调制波Uk_ref
Uk_ref=(ik_ref–ik)×(Kp1+Ksc1×s/(s2+2×ωsc1×s+(100π)2))
其中Kp1是第一准PR调节器的比例系数,Ksc1、ωsc1分别是第一准PR调节器的谐振系数和截止角频率;
(6)计算桥臂k的子模块电容电压平均值Uk_ave
Uk_ave=1/m×(Uk1+Uk2+…+Uk6)
其中Ukj为桥臂k的第j个子模块的电容电压采样值;
(7)将Ukj分别与Uk_ave做差带入P调节器后,P调节器输出与ik相乘得到桥臂k的第j个子模块的调制波叠加量Ukj_add
Ukj_add=(Ukj-Uk_ave)×ik×Kp2
其中Kp2是第一P调节器的比例系数;
(8)将Uk_ref和Ukj_add叠加得到桥臂k第j个子模块的调制波Ukj_ref
Ukj_ref=Uk_ref+Ukj_add
(9)将调制波Ukj_ref采用载波移相调制得到全桥子模块IGBT的开关信号;
(10)实时将Uave与全桥子模块电容电压参考值Uc_ref进行比较,当Uave大于等于Uc_ref时,可控充电阶段结束;闭合接触器KM2,风机接入***,执行基于六边形变流器的风机并网控制。
2.根据权利要求1所述的一种基于六边形变流器的风机并网***闭环预充电控制方法,其特征在于交流电网相电压额定值Ug为8165V,直流悬浮电容C大小为20mF,六边形变流器桥臂全桥子模块个数m为6,全桥子模块电容电压额定值Uc_ref为2500V,交流电抗器Larm_k为10mH,交流电网传输的功率P=3MW,控制周期T为0.0002s;R1=20,R2=20,R3=20,Kp1=90、Ksc1=1.2、ωsc1=6rad/s;Kp2=0.1。
CN202210630915.5A 2022-06-06 2022-06-06 一种基于六边形变流器的风机并网***闭环预充电控制方法 Pending CN115085521A (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210630915.5A CN115085521A (zh) 2022-06-06 2022-06-06 一种基于六边形变流器的风机并网***闭环预充电控制方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210630915.5A CN115085521A (zh) 2022-06-06 2022-06-06 一种基于六边形变流器的风机并网***闭环预充电控制方法

Publications (1)

Publication Number Publication Date
CN115085521A true CN115085521A (zh) 2022-09-20

Family

ID=83248320

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210630915.5A Pending CN115085521A (zh) 2022-06-06 2022-06-06 一种基于六边形变流器的风机并网***闭环预充电控制方法

Country Status (1)

Country Link
CN (1) CN115085521A (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117639196A (zh) * 2023-11-27 2024-03-01 滁州学院 一种永磁接触器分闸电容的恒流充电控制***

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117639196A (zh) * 2023-11-27 2024-03-01 滁州学院 一种永磁接触器分闸电容的恒流充电控制***

Similar Documents

Publication Publication Date Title
CN106451532B (zh) 一种多相直驱永磁风力发电变流一体化***及其控制方法
CN103280838B (zh) 一种基于开绕组结构的风力发电高压直流并网***及其控制方法
CN101316074B (zh) 风力发电***的背靠背三电平中点箝位变流器
CN101106338A (zh) 双向功率流高效节能变频器
CN202889279U (zh) 无刷双馈电机励磁控制装置
CN101640423A (zh) 一种用于风力发电的发电机***及变速控制方法
CN108879773B (zh) 一种六相风力发电机直流并网结构的控制方法
CN110920422B (zh) 一种基于电流源的大功率电动汽车充电装置及控制方法
CN108418226B (zh) 开绕组双逆变器光伏发电***的无功补偿控制方法
CN110797891B (zh) 一种双三相无刷直流电机的飞轮储能***及其控制方法
CN103401267A (zh) 一种小型风力发电机并网电路
CN113346559B (zh) 极弱电网下直驱风电***低电压穿越功率切换控制方法
CN116260348B (zh) 一种基于mmc的大容量电解制氢混合整流器及控制方法
CN103633875B (zh) 一种光伏扬水逆变器及其控制方法、及光伏扬水***
CN112086988B (zh) 一种电压源型换流器控制策略平滑切换方法
CN105958525B (zh) 一种永磁风力发电***的pwm并网逆变器控制方法
CN112217238A (zh) 一种无刷双馈发电机***及其控制方法
CN107147319B (zh) 非隔离光伏并网逆变器、光伏并网发电***及控制方法
CN115085521A (zh) 一种基于六边形变流器的风机并网***闭环预充电控制方法
CN112821791B (zh) 一种直流降半压四象限整流器
CN112134303B (zh) 一种基于六边形变流器风力发电***的无差拍电流控制方法
Wang et al. DC-link current optimal control of current source converter in DFIG
CN103236783B (zh) 一种拓宽双级式矩阵变换器功率因数角调节范围的方法
Zhu et al. DC-Link current optimal control of current source PWM converter
CN219960137U (zh) 一种用于三相***式光伏逆变器的控制***

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination