JPS635994B2 - - Google Patents
Info
- Publication number
- JPS635994B2 JPS635994B2 JP55053906A JP5390680A JPS635994B2 JP S635994 B2 JPS635994 B2 JP S635994B2 JP 55053906 A JP55053906 A JP 55053906A JP 5390680 A JP5390680 A JP 5390680A JP S635994 B2 JPS635994 B2 JP S635994B2
- Authority
- JP
- Japan
- Prior art keywords
- self
- excited
- voltage
- converter
- power
- 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.)
- Expired
Links
- 239000003990 capacitor Substances 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 238000004804 winding Methods 0.000 claims description 5
- 239000002131 composite material Substances 0.000 claims description 2
- 230000005540 biological transmission Effects 0.000 description 24
- 238000010586 diagram Methods 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 238000009413 insulation Methods 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
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
- 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
- H02M7/75—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 thyratron or thyristor type requiring extinguishing means
- H02M7/757—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 thyratron or thyristor type requiring extinguishing means using semiconductor devices only
- H02M7/7575—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 thyratron or thyristor type requiring extinguishing means using semiconductor devices only for high voltage direct transmission link
-
- 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]
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
- Direct Current Feeding And Distribution (AREA)
Description
【発明の詳細な説明】
この発明は直流送電に用いられる自励式変換装
置に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a self-commutated converter used for DC power transmission.
従来実用化されている直流送電用変換装置は、
電源電圧により転流を行なう他励式変換装置が用
いられている。しかし他励式変換装置は常に遅れ
の無効電力を多重に消費するため、調相設備が必
要とされる。他励式変換装置の代りに強制転流回
路を持つた自励式変換装置を用いることにより有
効電力の送電ばかりでなく、任意の無効電力を発
生できる変換装置が得られる。また、変換装置の
運転力率を常に１にすることも可能である。自励
式変換装置として、電圧形自励式インバータが適
用できることは、公知であり、この電圧形自励式
インバータを用いた無効電力発生装置も実用化さ
れていることは公知である。従来の自励式変換装
置を用いた直流送電システムを第１図にす。交流
系統１，２が２つの変換装置１２，２２及び直流
送電線路１０を介して連系されている。交流系統
１には変圧器１１が接続され、変圧器１１の他方
の端子には、サイリスタバルブ１２Ｕ〜１２Ｚに
より構成されたサイリスタ変換装置１２が接続さ
れ、交流系統１の交流電力は、変換装置１２によ
り直流電力に変換され、直流リアクトル１３を通
つて直流送電系統１０に送られる。直流送電系統
１０を通つた直流電力は受電側の直流リアクトル
２３を通つて、自励式変換装置２２に印加され
る。自励式変換装置２２はこの例では、電圧形の
自励式インバータが用いられている。そのため、
直流端子Ｐ，Ｎ間にはコンデンサ２４が接続され
ている。変換装置２２の例えば、１相分のアーム
２２Ｕ，２２Ｘは第２図ａの２２Ｉに示すよう
に、主サイリスタ２２UM，２２XM、補助サイ
リスタ２２UA，２２XAダイオード２２UD，２
２XD及びリアクトル２２ILとコンデンサ２２IC
よりなる転流回路により構成されている。補助サ
イリスタを点弧させることにより一方の直流端子
に接続された主サイリスタを消弧し、他方の直流
端子に接続された主サイリスタを点弧させ、順次
この動作をくり返し三相交流電圧を発生する。変
換装置２２の交流端子は変圧器２１に接続され、
変圧器２１の片方の端子は交流系統２に接続され
ている。一般に直流送電システムは絶縁協調の点
から、直流の片端、本例では（Ｎ）端子が接地さ
れている。変換装置２２へ印加される直流電力
は、交流電力に変換され変圧器２１を通つて交流
系統２に送られ、電力が交流系統１から２に送電
されたことになる。 The converter for DC power transmission that has been put into practical use is
A separately excited converter that performs commutation using the power supply voltage is used. However, a separately excited converter always consumes delayed reactive power multiple times, so phase adjustment equipment is required. By using a self-commutated converter having a forced commutation circuit instead of a separately-commutated converter, a converter that can not only transmit active power but also generate arbitrary reactive power can be obtained. It is also possible to always set the operating power factor of the converter to 1. It is well known that a voltage type self-excited inverter can be used as a self-excited converter, and it is also known that a reactive power generation device using this voltage type self-excited inverter has also been put into practical use. Figure 1 shows a DC power transmission system using a conventional self-excited converter. AC systems 1 and 2 are interconnected via two converters 12 and 22 and a DC transmission line 10. A transformer 11 is connected to the AC system 1, and the other terminal of the transformer 11 is connected to a thyristor converter 12 composed of thyristor valves 12U to 12Z. The power is converted into DC power and sent to the DC power transmission system 10 through the DC reactor 13. The DC power that has passed through the DC power transmission system 10 is applied to the self-excited converter 22 through the DC reactor 23 on the power receiving side. In this example, the self-excited converter 22 uses a voltage-type self-excited inverter. Therefore,
A capacitor 24 is connected between DC terminals P and N. For example, the arms 22U and 22X for one phase of the converter 22 include main thyristors 22UM and 22XM, auxiliary thyristors 22UA and 22XA diodes 22UD and 2, as shown in 22I in FIG.
2XD and reactor 22IL and capacitor 22IC
It is composed of a commutation circuit consisting of: By firing the auxiliary thyristor, the main thyristor connected to one DC terminal is turned off, and the main thyristor connected to the other DC terminal is fired, and this operation is repeated in sequence to generate three-phase AC voltage. . The AC terminal of the converter 22 is connected to the transformer 21,
One terminal of the transformer 21 is connected to the AC system 2. Generally, in a DC power transmission system, one end of the DC power, in this example, the (N) terminal, is grounded from the viewpoint of insulation coordination. The DC power applied to the converter 22 is converted to AC power and sent to the AC system 2 through the transformer 21, so that the power is transmitted from the AC system 1 to the AC system 2.
第１図の交換装置２２では、その交流出力電圧
が矩形波となるため、多くの高調波成分が含まれ
るので、フイルター等の設備が必要である。その
ため第３図に示すように、自励式変換装置を複数
台並列接続し、第３図の例では12相であるが、多
相化することにより、交流出力電圧を正弦波に近
づけ高調波の発生を少なくする方式も考えられて
いる。 In the switching device 22 shown in FIG. 1, the AC output voltage is a rectangular wave and contains many harmonic components, so equipment such as a filter is required. Therefore, as shown in Figure 3, multiple self-excited converters are connected in parallel, and by making them multi-phase, although the example in Figure 3 has 12 phases, the AC output voltage can be brought closer to a sine wave and harmonics can be eliminated. Methods are also being considered to reduce the occurrence.
直流送電において、送電距離のない、例えば直
流連系装置では、直流電圧を低くして、直流電流
を増やし、連系容量を増大させることも出来るが
長距離直流送電では、直流電圧を高くして、送電
損失を出来る限り減らす必要がある。そのため直
流電圧として125kvとか250kvにもしている。 In DC power transmission, for example, in a DC interconnection device where there is no power transmission distance, it is possible to lower the DC voltage and increase the DC current to increase the interconnection capacity, but for long distance DC power transmission, it is possible to increase the DC voltage and increase the interconnection capacity. , it is necessary to reduce transmission losses as much as possible. Therefore, the DC voltage is set to 125 kV or 250 kV .
このような直流送電システムを自励式変換装置
で構成するには、直流入力電圧125kvの自励式電
圧形インバータが必要とされ、各アームの半導体
素子は第２図ｂに示すように、直列接続する必要
がある。例えば4kvのサイリスタを用いるとして
も、125kvの変換装置のアームとするために120個
相当直列接続する必要がある。自励式電圧形イン
バータではターンオフタイムの短かいサイリスタ
が必要とされるが、直列接続するために特性をそ
ろえることが必要とされ、120個の数にわたつて、
残留キヤリヤーやもれ電流、ターンオンデツドタ
イムをそろえることは不可能に近い。そのため直
流入力電圧が125kvのように高い自励式電圧形イ
ンバータは入手することができず、長距離直流送
電用として良好な特性をもつ自励式変換装置を適
用することが困難であつた。そのため、直流送電
用変換装置として、もつぱら他励式変換装置が用
いられている。 To configure such a DC power transmission system with a self-excited converter, a self-excited voltage source inverter with a DC input voltage of 125 kV is required, and the semiconductor elements of each arm are connected in series, as shown in Figure 2b. There is a need to. For example, even if 4 kV thyristors are used, 120 thyristors would need to be connected in series to form a 125 kV converter arm. Self-commutated voltage source inverters require thyristors with short turn-off times, but in order to connect them in series, they must have the same characteristics, so 120 thyristors were used.
It is nearly impossible to match residual carrier, leakage current, and turn-on dead time. Therefore, self-excited voltage type inverters with a high DC input voltage of 125 kV are not available, and it has been difficult to apply self-excited converters with good characteristics for long-distance DC power transmission. Therefore, a separately excited type converter is used as a converter for direct current power transmission.
本発明は、直流電圧の低い自励式変換装置を複
数台用いるようにして上記従来のものの欠点を除
去しようとするものである。 The present invention aims to eliminate the drawbacks of the conventional converters by using a plurality of self-excited converters each having a low DC voltage.
本発明の一実施例を第４図に示す。交流系統１
と２は、変換装置１２，３及び直流送電線路１０
を介して連系されている。変換装置１２は変圧器
１１を介して交流系統１に接続され、変換装置１
２の直流出力端子は直流リアクトル１３を介して
直流送電線路１０に接続されている。変換装置３
は直列リアクトル２８を介して直流送電線路１０
に接続され、三つの電圧形自励式インバータ３
０，４０，５０を直列接続して構成されている。
各自励式インバータ３０，４０，５０の直流端子
にはそれぞれコンデンサ３１，４１，５１が接続
され、最下段のインバータ５０の負の直流端子
は、絶縁協調の点から接地されている。各自励式
インバータの構成は、電圧形自励式インバータと
同一のものであり、各相のアームは、主サイリス
タ、補助サイリスタ、ダイオード及び転流回路よ
り構成されている。各自励式インバータ３０，４
０，５０の交流出力端子は、多重変圧器２７の相
応する巻線２７３，２７４，２７５に接続され、
片側の巻線は各々の直列接続され中性点２７１を
形成し三相出力端子Ｕ，Ｖ，Ｗを介して交流系統
２と接続されている。自励式インバータ３０，４
０，５０は20゜ずつの位相差を持ち全体として18
相の自励式インバータとなつている。多重変圧器
２７の出力電圧は、第５図のベクトル図に示すよ
うに合成され正弦波形に近い三相出力電圧を発生
する。次に本装置の動作について説明する。交流
系統１の交流電力は他励式の変換装置１２により
直流電力に変換され、直流送電線路１０に送電さ
れ、さらに自励式変換装置３に送られる。18相の
自励式変換装置３により交流電力に変換され、交
流系統２に送られ、交流系統１から２に送電され
たことになる。例えば120kvの直流送電電圧が採
用された場合には、各自励式のインバータ３０，
４０，５０の直流電圧は３分の１の40kvになり自
励式インバータ３０，４０，５０の各アームの半
導体は、例えば、4kvの素子を用いて、40個程度
を直列接続すれば構成され、残留キヤリヤー、も
れ電流、ターンオンデツドタイム等の諸特性をそ
ろえることが可能であり、自励式インバータを製
作することができる。また36相の多重変圧器を用
いて10゜の位相差をもつ自励式インバータ６台を
直列接続して36相の自励式変換装置を用いる場合
には、120kvの直流電圧が採用されたシステムで
は、６分の１の20kvの直流電圧の自励式インバー
タを用いることができ、アームを構成するのに直
列接続される半導体の諸特性をそろえることがで
きる。自励式インバータの製作がより簡単にな
る。多相自励式インバータとして他に、12相、24
相、48相又は72相等いろいろ選定することができ
る。 An embodiment of the present invention is shown in FIG. AC system 1
and 2 are converters 12, 3 and DC transmission line 10
It is interconnected via. The conversion device 12 is connected to the AC system 1 via the transformer 11, and the conversion device 1
The second DC output terminal is connected to the DC power transmission line 10 via a DC reactor 13. Conversion device 3
is the DC power transmission line 10 via the series reactor 28
connected to three voltage type self-excited inverters 3
0, 40, and 50 are connected in series.
Capacitors 31, 41, and 51 are connected to the DC terminals of the self-excited inverters 30, 40, and 50, respectively, and the negative DC terminal of the lowest inverter 50 is grounded for insulation coordination. The configuration of each self-excited inverter is the same as that of a voltage-type self-excited inverter, and each phase arm is composed of a main thyristor, an auxiliary thyristor, a diode, and a commutation circuit. Self-excited inverter 30, 4
The AC output terminals 0, 50 are connected to the corresponding windings 273, 274, 275 of the multiplex transformer 27,
The windings on one side are connected in series to form a neutral point 271, and are connected to the AC system 2 via three-phase output terminals U, V, and W. Self-excited inverter 30, 4
0 and 50 have a phase difference of 20 degrees each, and the total is 18
It is a phase self-excited inverter. The output voltages of the multiplex transformer 27 are combined as shown in the vector diagram of FIG. 5 to generate a three-phase output voltage having a nearly sinusoidal waveform. Next, the operation of this device will be explained. The AC power of the AC system 1 is converted into DC power by the separately excited converter 12, and is transmitted to the DC power transmission line 10, and further sent to the self-excited converter 3. The 18-phase self-excited converter 3 converts the power into AC power, sends it to the AC system 2, and then transmits the power from AC system 1 to AC system 2. For example, if a DC transmission voltage of 120 kV is adopted, each self-excited inverter 30,
The DC voltage of 40, 50 becomes 40 kV , which is one-third, and the semiconductors in each arm of self-excited inverters 30, 40, 50 can be configured by using, for example, 4 kV elements and connecting about 40 of them in series. It is possible to match various characteristics such as residual carrier, leakage current, turn-on dead time, etc., and it is possible to manufacture a self-excited inverter. In addition, when using a 36-phase self-excited converter by connecting six self-excited inverters with a phase difference of 10° in series using a 36-phase multiplex transformer, a system that uses a DC voltage of 120 kV . In this case, a self-excited inverter with a DC voltage of 1/6 of 20 kV can be used, and various characteristics of the semiconductors connected in series to form the arm can be matched. Manufacturing a self-excited inverter becomes easier. In addition, as a multi-phase self-excited inverter, 12-phase, 24-phase
You can choose from various types such as phase, 48 phase or 72 phase.
以上説明したようにこの発明によれば、直流端
子にコンデンサを接続した電圧形自励式インバー
タを複数台用い、それらを直列接続し、多重変圧
器を用いて自励式変換装置を構成することにより
直流送電電圧の高いシステムに適用できる交直変
換装置を製作することが可能である。 As explained above, according to the present invention, a plurality of voltage-type self-excited inverters each having a capacitor connected to the DC terminal are used, and these are connected in series, and a self-excited converter is configured using multiple transformers. It is possible to manufacture an AC/DC converter that can be applied to systems with high transmission voltages.
又自動式変換装置の入手により、長距離直流送
電変換所においても調相設備やフイルター設備が
不用になり、変換所用地の縮少化が可能になる。 In addition, the acquisition of automatic converters eliminates the need for phase adjustment equipment and filter equipment even in long-distance DC power transmission conversion stations, making it possible to reduce the amount of land required for conversion stations.
第１図、第３図は従来の自励式変換装置を用い
た直流送電システムの構成図、第２図は自励式イ
ンバータのアームの構成を説明する図、第４図は
本発明の一実施例による自励式変換装置を用いた
直流送電システムの構成図、第５図は本発明の一
実施例である18相自励式インバータの出力電圧合
成ベクトル図である。
図中、１，２は交流系統、１０は直流送電系
統、１１は変圧器、１２は他励式変換装置、１
３，２８は直流リアクトル、２７は多重変圧器、
３０，４０，５０は自励式インバータ、３１，４
１，５１はコンデンサである。尚図中同一符号は
同一又は相当部分を示す。
Figures 1 and 3 are block diagrams of a DC power transmission system using a conventional self-excited converter, Figure 2 is a diagram illustrating the configuration of an arm of a self-excited inverter, and Figure 4 is an embodiment of the present invention. FIG. 5 is a block diagram of a DC power transmission system using a self-commutated converter according to the present invention, and FIG. 5 is an output voltage composite vector diagram of an 18-phase self-commutated inverter that is an embodiment of the present invention. In the figure, 1 and 2 are AC systems, 10 is a DC transmission system, 11 is a transformer, 12 is a separately excited converter, 1
3 and 28 are DC reactors, 27 is a multiplex transformer,
30, 40, 50 are self-excited inverters, 31, 4
1 and 51 are capacitors. Note that the same reference numerals in the drawings indicate the same or corresponding parts.
Claims (1)
バータの数と同数の巻線を持ち、前記巻線の出力
電圧のベクトル合成電圧が基本波以外の高周波を
相殺除去するように構成された多重変圧器、前記
各自励式インバータの正・負直流端子間に接続さ
れたコンデンサを備え、前記各電圧形自励式イン
バータの交流端子が前記多重変圧器の相応する巻
線に接続され、前記１つの電圧形自励式インバー
タの負の直流端子に、前記他の電圧形自励式イン
バータの正の直流端子を接続するようにして前記
複数個の電圧形自励式インバータを直列接続し、
接続されずに残つた正・負の直流２端子に変換さ
れる直流電力を加え、前記多重変圧器より交流電
力を得るようにしたことを特徴とする自励式変換
装置。1. A multiplex transformer having a plurality of voltage-type self-excited inverters and the same number of windings as the number of inverters, and configured such that a vector composite voltage of the output voltages of the windings cancels out high frequencies other than the fundamental wave. , a capacitor connected between the positive and negative DC terminals of each of the self-commutated inverters, wherein the AC terminal of each voltage-type self-excited inverter is connected to a corresponding winding of the multiplex transformer; Connecting the plurality of voltage type self-excited inverters in series such that the positive DC terminal of the other voltage type self-excited inverter is connected to the negative DC terminal of the excited inverter,
A self-commutated conversion device characterized in that DC power to be converted is added to the two positive and negative DC terminals that remain unconnected, and AC power is obtained from the multiplex transformer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5390680A JPS56150974A (en) | 1980-04-23 | 1980-04-23 | Converting device of self-excited type |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5390680A JPS56150974A (en) | 1980-04-23 | 1980-04-23 | Converting device of self-excited type |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56150974A JPS56150974A (en) | 1981-11-21 |
| JPS635994B2 true JPS635994B2 (en) | 1988-02-06 |
Family
ID=12955752
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5390680A Granted JPS56150974A (en) | 1980-04-23 | 1980-04-23 | Converting device of self-excited type |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56150974A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62126871A (en) * | 1985-11-26 | 1987-06-09 | Takaoka Ind Ltd | No-break inverter power source system |
-
1980
- 1980-04-23 JP JP5390680A patent/JPS56150974A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56150974A (en) | 1981-11-21 |
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