JPH11122819A - Dc ground fault detector - Google Patents
Dc ground fault detectorInfo
- Publication number
- JPH11122819A JPH11122819A JP9286302A JP28630297A JPH11122819A JP H11122819 A JPH11122819 A JP H11122819A JP 9286302 A JP9286302 A JP 9286302A JP 28630297 A JP28630297 A JP 28630297A JP H11122819 A JPH11122819 A JP H11122819A
- Authority
- JP
- Japan
- Prior art keywords
- ground fault
- power
- current
- power supply
- common current
- 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.)
- Withdrawn
Links
Landscapes
- Emergency Protection Circuit Devices (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Supply And Distribution Of Alternating Current (AREA)
- Inverter Devices (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、直流電力を交流電
力に変換する単相３線出力形の電力変換装置に備えら
れ、直流地絡事故を検出して電力変換装置を電力系統か
ら解列したり、その運転を停止させるための直流地絡検
出装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-phase three-wire output type power converter for converting DC power to AC power, detects a DC ground fault and disconnects the power converter from the power system. And a DC ground fault detection device for stopping the operation.
【０００２】[0002]
【従来の技術】図３は、電力系統と連系運転される太陽
光発電用電力変換装置等の単相３線出力形電力変換装置
の構成を直流地絡検出装置と共に示したものである。図
において、１は太陽電池等の直流電源、２は単相３線出
力形電力変換装置、２１はＩＧＢＴ等の半導体スイッチ
素子、２２はダイオード、２３はこれらのスイッチ素子
２１及びダイオード２２から構成される直列スイッチ回
路、２４はリアクトル、２５，２６はコンデンサ、２７
はＩＧＢＴ等の半導体スイッチ素子、２８はスイッチ素
子２７に逆並列接続されたダイオード、２９はこれらの
半導体スイッチ素子２７及びダイオード２８の並列回路
を２個直列に接続して構成されたハーフブリッジインバ
ータ、３０も同一構成のハーフブリッジインバータ、３
１，３２はフィルタ用リアクトル、３３，３４はフィル
タ用コンデンサ、３５は遮断器、３６は２つの単相交流
電源を有する単相３線式の電力系統である。この構成に
おいて、直列スイッチ回路２３及びコンデンサ２５，２
６は直流分圧回路を構成している。2. Description of the Related Art FIG. 3 shows a configuration of a single-phase three-wire output type power converter, such as a power converter for photovoltaic power generation, which is operated in connection with a power system, together with a DC ground fault detector. In the figure, 1 is a DC power source such as a solar cell, 2 is a single-phase three-wire output type power converter, 21 is a semiconductor switch element such as an IGBT, 22 is a diode, and 23 is a switch element 21 and a diode 22. Series switch circuit, 24 is a reactor, 25 and 26 are capacitors, 27
Is a semiconductor switch element such as an IGBT, 28 is a diode connected in anti-parallel to the switch element 27, 29 is a half-bridge inverter formed by connecting two parallel circuits of the semiconductor switch element 27 and the diode 28 in series, 30 is also a half-bridge inverter of the same configuration, 3
Reference numerals 1 and 32 denote filter reactors, 33 and 34 denote filter capacitors, 35 denotes a circuit breaker, and 36 denotes a single-phase three-wire power system having two single-phase AC power supplies. In this configuration, the series switch circuit 23 and the capacitors 25 and 2
Reference numeral 6 denotes a DC voltage dividing circuit.
【０００３】その動作を略述すると、直流電源１が両端
に接続されたコンデンサ２５の電圧Ｖ1は直流電源１の
電圧にクランプされ、直流電源１が接続されていない方
のコンデンサ２６の電圧Ｖ2がＶ1に等しくなるように制
御が行われる。すなわち、各コンデンサ２５，２６の電
圧を検出してＶ1，Ｖ2の偏差が零になるように直列スイ
ッチ回路２３のスイッチ素子２１の点弧期間を制御す
る。これによってハーフブリッジインバータ２９，３０
の直流電圧Ｖ1，Ｖ2が等しく制御され、ハーフブリッジ
インバータ２９，３０から出力される２つの単相交流電
力が単相３線式の電力系統３６に連系される。In brief, the operation is such that the voltage V 1 of the capacitor 25 to which the DC power supply 1 is connected at both ends is clamped to the voltage of the DC power supply 1 and the voltage V 1 of the capacitor 26 to which the DC power supply 1 is not connected. 2 control is performed so as to be equal to V 1. That is, the ignition period of the switch element 21 of the series switch circuit 23 is controlled such that the voltage between the capacitors 25 and 26 is detected and the deviation between V 1 and V 2 becomes zero. Thereby, the half-bridge inverters 29, 30
Controlled DC voltage V 1, V 2 are equal, the two single-phase AC power output from the half-bridge inverters 29 and 30 are interconnection to the power system 36 of the single-phase three-wire.
【０００４】ここで、単相３線式の電力系統３６は中性
点が接地されている。このため、図３に示すように直流
電源１の正極側で地絡事故（地絡抵抗をＲGとする）が
発生した場合、実線の矢印で示す地絡電流直流分Ｉdcと
破線の矢印で示す地絡電流交流分Ｉacとが流れ、火災等
の不測の事態を引き起こすおそれがある。Here, the single-phase three-wire power system 36 has a neutral point grounded. Therefore, (the ground fault resistance and R G) ground fault at the positive electrode side of the DC power source 1 as shown in FIG. 3 if occurs, dashed arrows and the earth fault current DC component I dc indicated by the solid arrows a ground fault current AC component I ac shown by the flow, may cause unexpected situations such as fire.
【０００５】そこでこの種の電力変換装置では、変流器
４１により直流電源１の正極側から流れ出る電流と負極
側に流れ込む電流との差分（コモン電流という）ＩGを
検出し、そのレベルから直流地絡事故を検出している。
具体的には、前記変流器４１、電流／電圧変換器４２、
ＰＷＭ成分除去用のフィルタ４３、比較器４４、検出レ
ベル設定器４５により直流地絡検出装置４を構成し、変
流器４１により検出したコモン電流ＩGに相当する電圧
を検出レベルと比較して比較器４４から直流地絡検出信
号を出力させ、遮断器３５の開放や電力変換装置の運転
停止等を行っていた。[0005] Therefore, in this type of power converter, (that common current) difference between the current and the current flowing into the anode side flowing from the positive electrode side of the DC power source 1 by the current transformer 41 detects the I G, DC from that level A ground fault has been detected.
Specifically, the current transformer 41, the current / voltage converter 42,
PWM component removal filter 43, a comparator 44, the detection level setter 45 constitute a DC ground fault detector 4, a voltage corresponding to the common current I G detected by the current transformer 41 as compared with the detection level The DC ground fault detection signal is output from the comparator 44 to open the circuit breaker 35 and stop the operation of the power converter.
【０００６】なお、図４は地絡電流直流分Ｉdc、コモン
電流ＩG、電力系統３６の２つの単相交流電源に起因す
る地絡電流交流分Ｉacと、その分流成分Ｉac１，Ｉac２
の波形の一例を示しており、図から明らかな如く、ＩG
＝Ｉdc＋Ｉacの関係がある。また、地絡電流交流分Ｉac
は、連系される電力系統３６の単相交流電源周波数（ｆ
s）の２倍の周波数成分を持っている。[0006] FIG. 4 is a ground fault current AC component I ac due to two of the single-phase AC power source of the ground fault current DC component I dc, the common current I G, the power system 36, the shunt component I ac 1, I ac 2
Of the waveform of I G , as can be seen from FIG.
= I dc + I ac . Also, ground fault current AC component I ac
Is the single-phase AC power supply frequency (f
s ) has twice the frequency component.
【０００７】[0007]
【発明が解決しようとする課題】上述した従来の直流地
絡検出装置では、単にコモン電流ＩGのレベルを所定の
検出レベルと比較して直流地絡事故を検出しているた
め、コモン電流ＩGの検出過程において変流器４１や制
御回路の温度ドリフト等により発生するオフセットの影
響で誤検出するおそれがある。特に、高抵抗接地の場
合、地絡事故によって発生するコモン電流ＩGのレベル
が小さいので、このような誤検出の可能性が一層高くな
る。そこで本発明は、オフセットや高抵抗接地の影響を
受けることなく直流地絡事故を確実に検出することがで
きる直流地絡検出装置を提供しようとするものである。In [0005] the above-described conventional DC ground fault detector is simply because it compares the level of the common current I G to a predetermined detection level detects a DC ground fault, the common current I In the process of detecting G , erroneous detection may occur due to the influence of an offset generated due to a temperature drift of the current transformer 41 or the control circuit. In particular, in the case of high-resistance ground, since the level of the common current I G generated by the ground fault is small, the possibility of such erroneous detection even higher. Therefore, an object of the present invention is to provide a DC ground fault detection device that can reliably detect a DC ground fault without being affected by an offset or a high-resistance ground.
【０００８】[0008]
【課題を解決するための手段】上記課題を解決するた
め、請求項１記載の発明は、直流電源の直流電力を交流
電力に変換して中性点接地の単相３線式電力系統に連系
する電力変換装置に接続され、かつ、前記直流電源から
前記電力系統の中性点を介して地絡電流が流れる直流地
絡事故を検出する直流地絡検出装置であって、前記直流
電源の正極を流れる電流と負極を流れる電流との差分を
コモン電流として取り込み、このコモン電流に基づいて
直流地絡を検出する直流地絡検出装置において、前記コ
モン電流から前記電力系統の電源周波数の２倍の周波数
成分の信号を抽出して直流地絡事故を検出する手段を備
えたものである。この直流地絡事故を検出する手段は、
例えば、系統電源周波数の２倍の周波数成分の信号を所
定の検出レベルと比較することにより実現可能である。In order to solve the above-mentioned problems, the invention according to claim 1 converts DC power of a DC power supply into AC power and connects the DC power to a neutral-point grounded single-phase three-wire power system. A DC ground fault detection device that is connected to a power conversion device, and detects a DC ground fault that causes a ground fault current to flow from the DC power source through a neutral point of the power system, In a DC ground fault detecting device that takes in a difference between a current flowing through a positive electrode and a current flowing through a negative electrode as a common current and detects a DC ground fault based on the common current, the DC current is twice the power frequency of the power system from the common current. And a means for detecting a DC ground fault by extracting a signal of the frequency component of The means for detecting this DC ground fault is
For example, it can be realized by comparing a signal of a frequency component twice as high as the system power supply frequency with a predetermined detection level.
【０００９】請求項２記載の発明は、請求項１記載の構
成に、前記コモン電流を増幅して所定の検出レベルと比
較することにより直流地絡事故を検出する手段を付加し
たものである。According to a second aspect of the present invention, a means for detecting a DC ground fault by amplifying the common current and comparing it with a predetermined detection level is added to the configuration of the first aspect.
【００１０】[0010]
【発明の実施の形態】以下、図に沿って本発明の実施形
態を説明する。図１は請求項１に記載した発明の実施形
態を示すもので、図３と同一の構成要素には同一の番号
を付してある。この実施形態における直流地絡検出装置
４Ａは、図３と同様に、コモン電流検出用の変流器４
１、電流／電圧変換器４２、ＰＷＭ成分除去用のフィル
タ４３を有している。更に、フィルタ４３の後段には、
電力系統３６の単相交流電源周波数ｆsの２倍の周波
数、すなわち２・ｆsの信号を通過させるバンドパスフ
ィルタ５１と、増幅器５２（ゲインＫ）とが接続され、
増幅器５２の出力が検出レベル設定器４５からの検出レ
ベルと共に比較器４４に入力されている。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the invention described in claim 1, and the same components as those in FIG. 3 are denoted by the same reference numerals. A DC ground fault detecting device 4A in this embodiment is similar to FIG.
1. It has a current / voltage converter 42 and a filter 43 for removing a PWM component. Further, after the filter 43,
2 times the frequency of the single-phase AC power source frequency f s of the power system 36, i.e. the band-pass filter 51 for passing a signal of 2 · f s, an amplifier 52 (gain K) and are connected,
The output of the amplifier 52 is input to the comparator 44 together with the detection level from the detection level setting unit 45.
【００１１】その動作を説明すると、本実施形態は、前
述のように地絡電流交流分Ｉacの周波数が２・ｆsとな
る点に着目している。すなわち、バンドパスフィルタ５
１によってフィルタ４３の出力から２・ｆsの周波数成
分の信号を検出する。そして、この信号を増幅器５２に
入力し、検出レベルから定まる適当な大きさに増幅して
比較器４４に入力することにより、検出ゲインと比較す
る。そして、その比較結果から直流地絡検出信号を得る
と共に、遮断器の開放や電力変換装置の運転停止等を行
なうものである。つまり、従来のようなコモン電流ＩG
の単純なレベル比較では、温度ドリフト等による変流器
や制御回路のオフセットによって誤検出するおそれがあ
るが、オフセットが存在する場合でもコモン電流ＩGか
ら連系系統の単相交流電源の２倍周波数成分の検出が可
能であるため、本実施形態によれば、高抵抗接地の場合
にも検出オフセット等に影響されることなく直流地絡事
故を検出することができる。[0011] To explain the operation, this embodiment is focused on the point that the frequency of the ground fault current AC component I ac as described above is 2 · f s. That is, the bandpass filter 5
1 by detecting the signal of the frequency component of the output from the 2 · f s of the filter 43. Then, this signal is input to the amplifier 52, amplified to an appropriate magnitude determined from the detection level, and input to the comparator 44, where it is compared with the detection gain. Then, a DC ground fault detection signal is obtained from the comparison result, and at the same time, the circuit breaker is opened, the operation of the power converter is stopped, and the like. In other words, the common current I G
In a simple level comparison, there is a possibility of erroneous detection by the offset of the current transformer and the control circuit due to temperature drift or the like, twice the single-phase AC power supply interconnection line from the common current I G even if offset exists Since the frequency component can be detected, according to the present embodiment, a DC ground fault can be detected without being affected by a detection offset or the like even in the case of high-resistance grounding.
【００１２】次に、請求項２に記載した発明の実施形態
を図２を参照しつつ説明する。図２に示す直流地絡検出
装置４Ｂは、図１の直流地絡検出装置４Ａにおける変流
器４１、電流／電圧変換器４２、ＰＷＭ成分除去用のフ
ィルタ４３、バンドパスフィルタ５１、増幅器５２、検
出レベル設定器４５及び比較器４４の他に、フィルタ４
３の出力信号が加えられる増幅器５３（ゲインＫ’）
と、その後段の比較器５５及び検出レベル設定器５４
と、比較器４４，５５の出力が二入力端子に加えられる
オア回路５６とを備えている。Next, an embodiment of the present invention will be described with reference to FIG. The DC ground fault detection device 4B shown in FIG. 2 includes a current transformer 41, a current / voltage converter 42, a filter 43 for removing a PWM component, a band-pass filter 51, an amplifier 52 in the DC ground fault detection device 4A in FIG. In addition to the detection level setting device 45 and the comparator 44, the filter 4
The amplifier 53 to which the output signal of No. 3 is added (gain K ')
And a comparator 55 and a detection level setting unit 54 at the subsequent stage.
And an OR circuit 56 to which the outputs of the comparators 44 and 55 are applied to two input terminals.
【００１３】この動作を説明すると、変流器４１、電流
／電圧変換器４２、フィルタ４３、バンドパスフィルタ
５１、増幅器５２、レベル設定器４５及び比較器４４の
構成により、直流地絡事故発生時には、図１と同様にコ
モン電流ＩGから連系系統の単相交流電源の２倍周波数
成分が検出され、オア回路５６を介して直流地絡検出信
号が出力される。一方、フィルタ４３の出力信号を増幅
器５３に入力して増幅することにより、温度ドリフト等
によるオフセットを加味した検出レベル設定器５４によ
る検出レベルに対しても地絡事故検出が可能になり、こ
の直流地絡検出信号がオア回路５６を介して出力される
ものである。The operation will be described. The current transformer 41, the current / voltage converter 42, the filter 43, the band-pass filter 51, the amplifier 52, the level setter 45 and the comparator 44 are constructed so that when a DC ground fault occurs, , twice the frequency components of the single-phase AC power source of the interconnection system from Likewise the common current I G and 1 are detected, the DC ground fault detector signal is output via an OR circuit 56. On the other hand, by inputting and amplifying the output signal of the filter 43 to the amplifier 53, the ground fault can be detected even with respect to the detection level of the detection level setting unit 54 taking into account the offset due to temperature drift or the like. The ground fault detection signal is output via the OR circuit 56.
【００１４】従ってこの実施形態によれば、低抵抗地絡
によるコモン電流ＩGの大幅な変化に対して連系交流電
源の２倍周波数成分の検出遅れが存在したとしても、コ
モン電流ＩGに相等する信号自体を増幅して検出レベル
と比較することにより、速やかな直流地絡検出が可能に
なる。これにより、図１の実施形態よりも一層確実に直
流地絡事故を検出することができる。[0014] Therefore, according to this embodiment, even if the detection delay of the double frequency component of the interconnection AC power source to a significant change in the common current I G according to the low-resistance ground fault is present, the common current I G By amplifying the equivalent signal itself and comparing it with the detection level, quick DC ground fault detection becomes possible. This makes it possible to more reliably detect a DC ground fault than in the embodiment of FIG.
【００１５】なお、本発明の直流地絡検出装置が適用さ
れる電力変換装置は、図３に示した構成に限定されるも
のではない。The power converter to which the DC ground fault detector of the present invention is applied is not limited to the configuration shown in FIG.
【００１６】[0016]
【発明の効果】以上のように請求項１記載の発明によれ
ば、コモン電流に含まれる系統電源の２倍周波数成分に
着目しているため、コモン電流の検出過程におけるオフ
セット等の影響を低減し、高抵抗接地の場合にも確実に
直流地絡を検出することができる。また、請求項２記載
の発明によれば、更にコモン電流を増幅してレベル比較
する手段を付加することにより、低抵抗接地の場合に請
求項１の発明による検出遅れが存在する時でも速やかか
つ正確な直流地絡検出が可能になり、一層確実に直流地
絡事故を検出することができる。As described above, according to the first aspect of the present invention, since attention is paid to the double frequency component of the system power supply included in the common current, the influence of offset and the like in the process of detecting the common current is reduced. However, a DC ground fault can be reliably detected even in the case of high-resistance grounding. According to the second aspect of the present invention, a means for further amplifying the common current and comparing the level is added, so that even when the detection delay according to the first aspect of the present invention exists in the case of low-resistance grounding, it can be quickly and quickly performed. Accurate DC ground fault detection is possible, and a DC ground fault accident can be detected more reliably.
【図１】請求項１に記載した発明の実施形態を示すブロ
ック図である。FIG. 1 is a block diagram showing an embodiment of the invention described in claim 1;
【図２】請求項２に記載した発明の実施形態を示すブロ
ック図である。FIG. 2 is a block diagram showing an embodiment of the invention described in claim 2;
【図３】従来技術を示す回路図である。FIG. 3 is a circuit diagram showing a conventional technique.
【図４】直流地絡事故時の電流波形図である。FIG. 4 is a current waveform diagram at the time of a DC ground fault.
１ 直流電源 ２ 単相３線出力形電力変換装置 ４Ａ，４Ｂ 直流地絡検出装置 ３６ 単相３線式電力系統 ４１ 変流器 ４２ 電流／電圧変換器 ４３ フィルタ ４４，５５ 比較器 ４５，５４ 検出レベル設定器 ５１ バンドパスフィルタ ５２，５３ 増幅器 ５６ オア回路 ＲG 接地抵抗Reference Signs List 1 DC power supply 2 Single-phase three-wire output power converter 4A, 4B DC ground fault detector 36 Single-phase three-wire power system 41 Current transformer 42 Current / voltage converter 43 Filter 44, 55 Comparator 45, 54 Detection Level setting device 51 Band pass filter 52, 53 Amplifier 56 OR circuit RG Ground resistance
Claims (2)
て中性点接地の単相３線式電力系統に連系する電力変換
装置に接続され、かつ、前記直流電源から前記電力系統
の中性点を介して地絡電流が流れる直流地絡事故を検出
する直流地絡検出装置であって、前記直流電源の正極を
流れる電流と負極を流れる電流との差分をコモン電流と
して取り込み、このコモン電流に基づいて直流地絡を検
出する直流地絡検出装置において、 前記コモン電流から前記電力系統の電源周波数の２倍の
周波数成分の信号を抽出して直流地絡事故を検出する手
段を備えたことを特徴とする直流地絡検出装置。1. A power converter for converting a DC power of a DC power supply into an AC power to be connected to a neutral-point grounded single-phase three-wire power system and connecting the DC power source to the power system. A DC ground fault detection device that detects a DC ground fault in which a ground fault current flows through a neutral point, and captures a difference between a current flowing through a positive electrode of the DC power supply and a current flowing through a negative electrode as a common current. A DC ground fault detection device that detects a DC ground fault based on a common current, comprising: a unit that extracts a signal of a frequency component twice as high as a power supply frequency of the power system from the common current to detect a DC ground fault. A DC ground fault detection device.
て、 前記コモン電流を増幅して検出レベルと比較することに
より直流地絡事故を検出する手段を更に備えたことを特
徴とする直流地絡検出装置。2. The DC ground fault detecting device according to claim 1, further comprising: a unit for detecting a DC ground fault by amplifying the common current and comparing it with a detection level. Tangle detection device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9286302A JPH11122819A (en) | 1997-10-20 | 1997-10-20 | Dc ground fault detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9286302A JPH11122819A (en) | 1997-10-20 | 1997-10-20 | Dc ground fault detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH11122819A true JPH11122819A (en) | 1999-04-30 |
Family
ID=17702629
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9286302A Withdrawn JPH11122819A (en) | 1997-10-20 | 1997-10-20 | Dc ground fault detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH11122819A (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1107439A2 (en) * | 1999-12-01 | 2001-06-13 | Canon Kabushiki Kaisha | Interconnection power converter and power generation apparatus using the same |
| EP1229629A2 (en) * | 2001-02-02 | 2002-08-07 | Canon Kabushiki Kaisha | Apparatus and method of detecting ground fault of solar power generation system |
| EP1408594A2 (en) * | 2002-10-10 | 2004-04-14 | Sanyo Electric Co. Ltd | DC ground fault detector and system-interconnected generation device using the DC ground fault detector |
| CN100347555C (en) * | 2005-03-11 | 2007-11-07 | 天津大学 | Rang-measuring method for transmission line one-phase earth fault of small current neutral grounding system |
| JP2008170330A (en) * | 2007-01-12 | 2008-07-24 | Omron Corp | Fault current detection circuit and fault current detection method |
| US7486082B2 (en) | 2002-07-22 | 2009-02-03 | Fujitsu Limited | Anomaly detection in inverter system |
| JP2011196729A (en) * | 2010-03-18 | 2011-10-06 | Kansai Electric Power Co Inc:The | Leak detection device and method for dc circuit |
| DE102011084219A1 (en) * | 2011-10-10 | 2013-04-11 | Bender Gmbh & Co. Kg | Method and device for determining insulation resistance in grounded IT systems |
| JP2015529440A (en) * | 2012-06-01 | 2015-10-05 | エスエムエー ソーラー テクノロジー アーゲー | Insulation resistance measurement for inverter |
| CN107230967A (en) * | 2017-06-07 | 2017-10-03 | 国网山西省电力公司电力科学研究院 | voltage transformer secondary neutral point potential drift monitoring method |
| CN110754034A (en) * | 2017-07-18 | 2020-02-04 | 东芝三菱电机产业系统株式会社 | Ground fault detector and power conditioner |
| JP2021135065A (en) * | 2020-02-21 | 2021-09-13 | 公益財団法人鉄道総合技術研究所 | Ground fault detector and ground fault detection method |
-
1997
- 1997-10-20 JP JP9286302A patent/JPH11122819A/en not_active Withdrawn
Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1107439A2 (en) * | 1999-12-01 | 2001-06-13 | Canon Kabushiki Kaisha | Interconnection power converter and power generation apparatus using the same |
| EP1107439A3 (en) * | 1999-12-01 | 2005-02-02 | Canon Kabushiki Kaisha | Interconnection power converter and power generation apparatus using the same |
| EP1229629A3 (en) * | 2001-02-02 | 2006-01-25 | Canon Kabushiki Kaisha | Apparatus and method of detecting ground fault of solar power generation system |
| EP1229629A2 (en) * | 2001-02-02 | 2002-08-07 | Canon Kabushiki Kaisha | Apparatus and method of detecting ground fault of solar power generation system |
| US6930868B2 (en) | 2001-02-02 | 2005-08-16 | Canon Kabushiki Kaisha | Apparatus and method of detecting ground fault of solar power generation system |
| US7492162B2 (en) | 2002-07-22 | 2009-02-17 | Fujitsu Limited | Inverter system |
| US7486082B2 (en) | 2002-07-22 | 2009-02-03 | Fujitsu Limited | Anomaly detection in inverter system |
| US7598748B2 (en) | 2002-07-22 | 2009-10-06 | Fujitsu Limited | Inverter system |
| EP1408594A3 (en) * | 2002-10-10 | 2006-09-20 | Sanyo Electric Co. Ltd | DC ground fault detector and system-interconnected generation device using the DC ground fault detector |
| EP1408594A2 (en) * | 2002-10-10 | 2004-04-14 | Sanyo Electric Co. Ltd | DC ground fault detector and system-interconnected generation device using the DC ground fault detector |
| CN100347555C (en) * | 2005-03-11 | 2007-11-07 | 天津大学 | Rang-measuring method for transmission line one-phase earth fault of small current neutral grounding system |
| JP2008170330A (en) * | 2007-01-12 | 2008-07-24 | Omron Corp | Fault current detection circuit and fault current detection method |
| JP2011196729A (en) * | 2010-03-18 | 2011-10-06 | Kansai Electric Power Co Inc:The | Leak detection device and method for dc circuit |
| DE102011084219B4 (en) * | 2011-10-10 | 2013-07-04 | Bender Gmbh & Co. Kg | Method and device for determining an actual insulation resistance in IT systems with a functional grounding resistance |
| DE102011084219A1 (en) * | 2011-10-10 | 2013-04-11 | Bender Gmbh & Co. Kg | Method and device for determining insulation resistance in grounded IT systems |
| US9182431B2 (en) | 2011-10-10 | 2015-11-10 | Bender Gmbh & Co. Kg | Method and apparatus for determining an insulation resistance in a grounded isole terre system |
| JP2015529440A (en) * | 2012-06-01 | 2015-10-05 | エスエムエー ソーラー テクノロジー アーゲー | Insulation resistance measurement for inverter |
| US9797853B2 (en) | 2012-06-01 | 2017-10-24 | Sma Solar Technology Ag | Insulation resistance measurement for inverters |
| CN107230967A (en) * | 2017-06-07 | 2017-10-03 | 国网山西省电力公司电力科学研究院 | voltage transformer secondary neutral point potential drift monitoring method |
| CN110754034A (en) * | 2017-07-18 | 2020-02-04 | 东芝三菱电机产业系统株式会社 | Ground fault detector and power conditioner |
| CN110754034B (en) * | 2017-07-18 | 2021-07-16 | 东芝三菱电机产业系统株式会社 | Ground fault detector and power conditioner |
| JP2021135065A (en) * | 2020-02-21 | 2021-09-13 | 公益財団法人鉄道総合技術研究所 | Ground fault detector and ground fault detection method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11909353B2 (en) | Ground-fault detecting device and related method | |
| JPH11122819A (en) | Dc ground fault detector | |
| US11632060B2 (en) | Power conversion device | |
| CN108414880A (en) | Phase fault detection method before one kind starts for frequency converter | |
| Anand et al. | Open switch fault detection in Cascaded H-Bridge Multilevel Inverter using normalised mean voltages | |
| JP3474984B2 (en) | DC component detector | |
| JPH0984254A (en) | Power supply system, inverter equipment, and distributed power supply system | |
| JP3910357B2 (en) | Electric vehicle control device | |
| CN113794394B (en) | Controller and control circuit | |
| US11283368B2 (en) | Open phase detection system for power conversion system | |
| JP3614257B2 (en) | Inverter parallel controller | |
| CN114389540A (en) | Conversion device, current sensor failure detection method thereof and new energy power generation system | |
| JP2000023470A (en) | Transformerless inverter protection apparatus | |
| JP2000023371A (en) | Power converter | |
| US20220334151A1 (en) | Open-phase detection circuit and power conversion apparatus | |
| JPH07264873A (en) | Power converter | |
| JP2721477B2 (en) | Grid-connected inverter for solar cells | |
| JP2007151358A (en) | Dc voltage step-down circuit and electric power conversion system | |
| MKP et al. | Sliding mode observer based open-circuit fault detection in the heric pv inverter | |
| CN213879669U (en) | Current-limiting protection circuit of inverter and inverter circuit | |
| WO2023281643A1 (en) | Power conversion device and failure diagnosis method for switching element | |
| JPH06327258A (en) | Protector for system interconnection | |
| CN109742775B (en) | Three-phase load balancing device and method | |
| JP3425220B2 (en) | Active filter for electric power | |
| JPH08251938A (en) | Inverter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20050104 |