WO2010057532A1 - Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques - Google Patents

Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques Download PDF

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Publication number
WO2010057532A1
WO2010057532A1 PCT/EP2008/065976 EP2008065976W WO2010057532A1 WO 2010057532 A1 WO2010057532 A1 WO 2010057532A1 EP 2008065976 W EP2008065976 W EP 2008065976W WO 2010057532 A1 WO2010057532 A1 WO 2010057532A1
Authority
WO
WIPO (PCT)
Prior art keywords
voltage
inductor
terminal
capacitor
harmonics
Prior art date
Application number
PCT/EP2008/065976
Other languages
English (en)
Inventor
Lennart Harnefors
Björn JACOBSON
Original Assignee
Abb Technology Ag
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 Abb Technology Ag filed Critical Abb Technology Ag
Priority to PCT/EP2008/065976 priority Critical patent/WO2010057532A1/fr
Priority to US13/130,124 priority patent/US8553435B2/en
Priority to EP08875350A priority patent/EP2359463A1/fr
Priority to CN200880132052.7A priority patent/CN102224669B/zh
Priority to KR1020117011555A priority patent/KR101320214B1/ko
Publication of WO2010057532A1 publication Critical patent/WO2010057532A1/fr

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Classifications

    • 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
    • H02M1/12—Arrangements for reducing harmonics from ac input or output
    • H02M1/126—Arrangements for reducing harmonics from ac input or output using passive filters
    • 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
    • H02M1/12—Arrangements for reducing harmonics from ac input or output
    • 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
    • H02M1/14—Arrangements for reducing ripples from dc input or output
    • 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
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/66—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal
    • H02M7/68—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal by static converters
    • H02M7/72—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/79—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal 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
    • H02M7/797—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal 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

Definitions

  • the invention is related to a power converter with multi-level voltage output described as a device for converting a DC voltage into an AC voltage and vice versa comprising at least one phase leg with a first voltage source and a first inductor connected in series between a first DC terminal and a first AC terminal and with a second inductor and a second voltage source connected in series between the first AC terminal and a second DC terminal, where each of the voltage sources comprises at least a first and a second submodule in series-connection, each submodule comprising at least one power electronic switch connected in parallel with at least one capacitor.
  • multi-level converters are known to be used in order to reduce harmonic distortion in the output of voltage source converters.
  • a multilevel converter is a converter where the output voltage - or, in case of a multiphase converter, the voltages - can assume several discrete levels, as can be seen for example in DE10103031.
  • a multi-level converter according to DE10103031 which in addition comprises at least one inductor in each phase leg as well as regulating means to regulate a circulating current flowing through the phase legs, i.e., the current that closes between the phase legs but does not enter the AC grid through the AC terminal.
  • the voltage rating of the power electronic switches of the converter must allow for the extra voltage needed to regulate the circulating currents in the desired manner.
  • the device for converting a DC voltage into an AC voltage and vice versa as described above comprises according to the invention a passive electronic filter which is arranged between the first and the second inductor as well as the first AC terminal.
  • the passive electronic filter is adjusted to reduce harmonics in a circulating current.
  • the invention is based on the recognition of the fact that the desired manner in which the circulating currents should best be regulated is to reduce the harmonics which occur at specific frequencies in the circulating current, rather than to reduce the circulating currents in general. What the inventor realized is that at each switching event in the power electronic switches of the converter, harmonics appear in the circulating current causing increased losses. As a worst case, some of the harmonics with distinctively high amplitude in the circulating currents could even lead to system instability. The introduction of additional inductors, as described in WO 2008/067785 A1 , helps to obtain a general current limitation in the converter circuit but does nothing to avoid the distinctive harmonics as such.
  • control unit which controls the power semiconductor switches sees and takes into account the most disturbing components of the circulating currents, so that the requirements on the voltage rating of the power semiconductor switches can thereby be reduced.
  • a closer look at the harmonics in the circulating currents revealed the following:
  • the sum of the voltage ripple over the submodules of both phase module branches in one phase leg shows in its frequency spectrum a main component at twice the fundamental frequency of the AC voltage.
  • This main frequency component creates a parasitic harmonic component in the circulating current that is also of twice the fundamental frequency. Unless this component is somehow limited, increased losses will result; possibly even loss of system stability.
  • the parameters of the electronic filter are chosen so that harmonics at twice the fundamental frequency of the AC voltage are reduced, thereby specifically reducing the main disturbing component of the circulating current.
  • Fig. 1 shows a converter topology as is known from the art
  • Fig. 2 shows the setup of the voltage sources in the phase legs of the converter of Fig. 1 as known from the art
  • Fig. 3 shows two different embodiments of the submodules in the converter of
  • Figs. 1 and 2 show one phase leg of a converter with an electronic filter according to one embodiment of the invention
  • Fig. 5 shows the modulus of admittance for the circulating current of the embodiment of Fig. 4 with appropriate parameter settings and
  • Fig. 6 shows one phase leg of a converter with an electronic filter according. to another embodiment of the invention
  • Fig. 7 shows one phase leg of a converter with an electronic filter according to
  • the device for converting a DC voltage into an AC voltage and vice versa can contain either a single phase leg or multiple phase legs, depending on how many phases the AC voltage has.
  • Fig. 1 shows a three-phase converter known in the art.
  • the three phase legs 1 , 2 and 3 of the device of Fig. 1 each comprise two so-called arms in series-connection: a positive, upper arm which is connected to a first DC terminal 4 at a positive voltage level, and a negative, lower arm, which is connected to a second DC terminal 5 at zero or a negative voltage level.
  • Each positive arm comprises a series-connection of an upper voltage source Uvpi and a first inductor 9, 1 1 or 13, respectively, and each negative arm comprises a second inductor 10, 12 or 14, respectively, and a lower voltage source Uvni, where i stands for the number of the corresponding phase leg.
  • the midpoint or connection point between the first and second inductors of each phase leg is each connected to an AC terminal 6, 7 or 8, respectively. All the phase legs are connected in parallel to each other and to the two DC terminals 4 and 5.
  • each voltage source is made up of a series connected string of submodules 15, where at least two submodules 15 are comprised in one such string.
  • the submodules have the form of commutation cells, each cell comprising two valves and a large DC capacitor holding a direct voltage.
  • the main valves are equipped with a power electronic switch 16 with turn-off capability and a free-wheeling diode in anti-parallel connection to the switch.
  • the corresponding submodule can assume one of two switching states, where in state one zero voltage or in state two the capacitor voltage is applied to the output.
  • the converter according to Figs. 1 to 3 is additionally equipped with a passive electronic filter in each phase leg, as is depicted in Fig. 4 for phase leg 1.
  • a first capacitor 20 is arranged in series with the first and the second inductors 9 and 10, a third inductor 18 is arranged between the first inductor 9 and the first AC terminal 6 and a fourth inductor 19 is arranged between the second inductor 10 and the first AC terminal 6.
  • Fig. 4 have the following meaning: u vpl n voltage of the voltage source in positive or negative arm, respectively; i vpl n current in positive/negative arm; i v output current at AC terminal; u f voltage at AC terminal (AC voltage); u p voltage across first capacitor; i p current through first capacitor;
  • u vc is the driving voltage for the circulating current. This voltage is controllable, i.e., it can be made to follow a reference u v ⁇ f , but it also contains a parasitic term ⁇ « ve as
  • u p K ⁇ P + r(i vp -i p ) + L v - " + r(i m -i p ) ⁇ . d d t t d d t t (4) di p di 1
  • the blocking ability of the electronic filter according to Fig. 4 is in the following illustrated with the help of an example. Suppose that for a converter with the
  • the electronic filter may comprise two sub-filters, each placed in one of the two arms of the phase leg, as shown in Fig. 6.
  • a first capacitor 20 and a third inductor 18, forming a first sub-filter are arranged in parallel with each other and between the first inductor 9 and the first AC terminal 6.
  • a second capacitor 21 and a fourth inductor 19, forming a second sub- filter are arranged in parallel with each other and between the second inductor 10 and the first AC terminal 6.
  • the total installed capacitance of the system in Fig. 6 is four times that of the system according to Fig. 4, i.e. 4C p instead of C p , where C p is given by equation (6).
  • the voltage across each capacitance in Fig. 6 is only half of that in Fig. 4.
  • a passive electronic filter comprising at least a capacitor and at least an inductor, where the inductor has naturally an inner resistance, is sufficient to both block the most disturbing harmonic component of the circuit current and at the same time achieve reasonable damping for the other frequency ranges.
  • a resistor 21 can be arranged in parallel with the first capacitor 20, as is depicted in Fig. 7. The resistance of that resistor 21 needs to be chosen considerably high in order to avoid unnecessary losses.
  • a control unit which in any case would be present in a converter according to the invention to control the output voltages of the voltage sources in each phase leg to perform the AC/DC conversion, could be adjusted in such a way, that the voltages of the first and the second voltage sources are controlled so that harmonics introduced by the electronic filter are reduced.
  • the most disturbing harmonics introduced by the electronic filter are those at about triple the fundamental frequency, i.e., just below 150 Hz. These can be reduced by either introducing the above desribed resistor or by controlling the voltage sources accordingly.

Abstract

L'invention porte sur un dispositif pour convertir une tension continue en une tension alternative et réciproquement, qui comprend au moins une branche de phase comprenant une première source de tension et une première bobine d'induction (9) connectées en série entre une première borne de courant continu (CC) (4) et une première borne de courant alternatif (CA) (6) et comprenant une seconde bobine d'induction (10) et une seconde source de tension connectées en série entre la première borne CA (6) et une seconde borne CC (5), chacune des sources de tension comprenant au moins des premier et second sous-modules (15) connectés en série, chaque sous-module (15) comprenant au moins un interrupteur électronique de puissance connecté en parallèle à au moins un condensateur. Dans le dispositif, un filtre électronique passif est disposé entre les première et seconde bobines d'induction ainsi que la première borne CA pour réduire des harmoniques dans un courant en circulation.
PCT/EP2008/065976 2008-11-21 2008-11-21 Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques WO2010057532A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
PCT/EP2008/065976 WO2010057532A1 (fr) 2008-11-21 2008-11-21 Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques
US13/130,124 US8553435B2 (en) 2008-11-21 2008-11-21 Power converter with multi-level voltage output and harmonics filter
EP08875350A EP2359463A1 (fr) 2008-11-21 2008-11-21 Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques
CN200880132052.7A CN102224669B (zh) 2008-11-21 2008-11-21 具有多电平电压输出和谐波滤波器的功率转换器
KR1020117011555A KR101320214B1 (ko) 2008-11-21 2008-11-21 멀티레벨 전압 출력 및 고조파 필터를 갖는 전력 변환기

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2008/065976 WO2010057532A1 (fr) 2008-11-21 2008-11-21 Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques

Publications (1)

Publication Number Publication Date
WO2010057532A1 true WO2010057532A1 (fr) 2010-05-27

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Family Applications (1)

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PCT/EP2008/065976 WO2010057532A1 (fr) 2008-11-21 2008-11-21 Convertisseur de courant à multiples niveaux de tension de sortie et filtre d'harmoniques

Country Status (5)

Country Link
US (1) US8553435B2 (fr)
EP (1) EP2359463A1 (fr)
KR (1) KR101320214B1 (fr)
CN (1) CN102224669B (fr)
WO (1) WO2010057532A1 (fr)

Families Citing this family (9)

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CN102823122B (zh) * 2010-04-15 2016-01-20 Abb研究有限公司 具有第二和第三阶谐波降低滤波器的模块化多级功率转换器
CN103219875B (zh) * 2013-04-27 2016-02-03 东南大学 一种基于互补耦合谐振的mmc环流抑制技术
CN103199681B (zh) * 2013-04-27 2016-01-13 东南大学 一种基于二次谐波陷阱的mmc环流抑制技术
CN103199725A (zh) * 2013-04-27 2013-07-10 东南大学 一种基于并联谐振的mmc环流抑制策略
WO2015039708A1 (fr) * 2013-09-23 2015-03-26 Abb Technology Ltd Convertisseur continu-continu
US9917515B2 (en) 2014-06-24 2018-03-13 Technische Universiteit Eindhoven Cascadable modular 4-switch extended commutation cell
CN109716640B (zh) 2016-09-01 2020-12-22 Abb电网瑞士股份公司 模块化多电平电压源变流器中的循环电流控制
KR101862615B1 (ko) 2016-09-23 2018-05-31 한국전력공사 하이브리드 능동 필터를 포함하는 전압형 컨버터
CN111327219B (zh) * 2020-02-25 2021-01-12 上海电力大学 一种用于抑制模块化多电平变换器环流的无源一致性控制方法

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GB2397445A (en) * 2003-01-14 2004-07-21 Alstom Power transmission circuits
EP1544992A1 (fr) * 2003-12-16 2005-06-22 ABB Schweiz AG Circuit convertisseur avec deux convertisseurs partiels
US20060227582A1 (en) * 2005-03-31 2006-10-12 Lixiang Wei Rectifier for reducing current harmonics from unbalanced source
WO2007033852A2 (fr) * 2005-09-21 2007-03-29 Siemens Aktiengesellschaft Procede pour commander un convertisseur de courant polyphase au moyen d'accumulateurs d'energie repartis
WO2008067785A1 (fr) * 2006-12-08 2008-06-12 Siemens Aktiengesellschaft Dispositif pour transformer un courant électrique

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GB2397445A (en) * 2003-01-14 2004-07-21 Alstom Power transmission circuits
EP1544992A1 (fr) * 2003-12-16 2005-06-22 ABB Schweiz AG Circuit convertisseur avec deux convertisseurs partiels
US20060227582A1 (en) * 2005-03-31 2006-10-12 Lixiang Wei Rectifier for reducing current harmonics from unbalanced source
WO2007033852A2 (fr) * 2005-09-21 2007-03-29 Siemens Aktiengesellschaft Procede pour commander un convertisseur de courant polyphase au moyen d'accumulateurs d'energie repartis
WO2008067785A1 (fr) * 2006-12-08 2008-06-12 Siemens Aktiengesellschaft Dispositif pour transformer un courant électrique

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Also Published As

Publication number Publication date
KR101320214B1 (ko) 2013-10-21
CN102224669B (zh) 2014-04-16
KR20110074779A (ko) 2011-07-01
US8553435B2 (en) 2013-10-08
US20110261598A1 (en) 2011-10-27
EP2359463A1 (fr) 2011-08-24
CN102224669A (zh) 2011-10-19

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