JP2009027879A - Contamination detector for power converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contamination detector for a power converter which detects that contamination of a power converter is in a prescribed state so as to previously prevent the occurrence of a short-circuit accident or the like. <P>SOLUTION: A high-voltage side resistor 13 of a high-voltage side resistor part 10 and a low-voltage side resistor 14 of a low-voltage side resistor part 11 are provided in a casing 16 of a reactive power compensator 1. The high-voltage side resistor and the low-voltage side resistor are serially connected with each other so as to be inserted between a P-side bus-bar 5 of a DC high-voltage side line and an N-side bus-bar 6 of a low-voltage side line. A voltage at both ends of the low-voltage side resistor 14 is measured by a voltage measurement part 12 so as to execute contamination detection inside the casing 16. When a voltage at both ends of the low-voltage side resistor 14 becomes less than or equal to a prescribed setting voltage value, it is determined that a contamination state inside the casing 16 is abnormal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fouling detection device for a power converter used in factory equipment, substation equipment, and the like.

  Conventionally, in power converters used in factory facilities, substation facilities, etc., such as reactive power compensators, AC / DC converters, frequency converters, grid interconnection converters, and other power supply equipment in general, the equipment is usually contaminated. It was not equipped with a device to detect. In particular, when it is necessary to detect the contamination of an apparatus, for example, in a room where a plurality of apparatuses are installed, the components in the air in the room are analyzed, and the chemical concentration is determined by the concentration of the components in the air corresponding to the analyzed contamination. It has been attempted to detect fouling.

  In this way, it is impossible to grasp the pollution status of each power converter, so in power converters used in places where the surrounding environment is poor, such as places with a lot of dust and places with high humidity, Continuing the use will cause contamination and deterioration of insulation, and in the worst case, a DC short-circuit accident of the main circuit will occur.

  For this reason, it is necessary to make it possible to easily grasp the status of contamination of each power conversion device, taking into account that the power conversion device has a large impact from causing an accident. Thus, it is important to prevent the deterioration of the insulation and the occurrence of an accident such as a short circuit due to the progress of fouling.

  The present invention has been made in view of the above situation, and its purpose is to detect occurrence of a short-circuit accident or the like by detecting that the contamination of the power conversion device has become a predetermined situation. An object of the present invention is to provide a contamination detection device for a power conversion device that can be prevented.

The contamination detection device for the power conversion device of the present invention,
The high voltage side resistance of the high voltage side resistance part and the low voltage side resistance of the low voltage side resistance part provided in the casing of the power converter are connected in series between the DC high voltage side line and the low voltage side line. A contamination detection device for a power converter that detects contamination in the housing by measuring the voltage across the low-voltage side resistor,
When the voltage at both ends of the low-voltage side resistance becomes equal to or lower than a predetermined set voltage value, the contamination state in the casing is determined to be abnormal.

Further, the low-voltage side resistance portion is installed such that a decrease in both-end voltage due to contamination of the low-voltage-side resistance is larger than a decrease in both-end voltage due to contamination of the high-voltage-side resistance. Is what
Furthermore, the low voltage side resistance portion is characterized in that it is installed at a position where the progress of fouling proceeds faster than the high voltage side resistance portion,
Furthermore, the low voltage side resistance portion is configured such that the low voltage side resistance is attached to a horizontal surface or a substantially horizontal surface of the housing via an insulating support member, and the high voltage side resistance portion is configured to be connected to the high voltage side. The resistor is attached to a vertical or substantially vertical surface of the casing via an insulating support member,
Further, the low-voltage side resistance part and the high-voltage side resistance part are insulated from the insulating mounting plate of each resistance part, in which the low-voltage side resistance and the high-voltage side resistance are insulated and supported by the casing, respectively. It is attached via an attachment member, and the area of the insulating mounting plate of the low-voltage-side resistance portion that is damaged is larger than the area of the high-voltage-side resistance portion of the insulating mounting plate that is damaged. To do.

  According to the present invention, it is possible to easily detect that the contamination status of each power conversion device has become a predetermined status, thereby preventing an accident such as a short circuit from occurring. An effect such as being able to be obtained can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, a first embodiment will be described with reference to FIGS. FIG. 1 is a circuit diagram of a reactive power compensator provided with a contamination detection device, and FIG. 2 is a schematic configuration diagram of the contamination detection device.

  1 and 2, reference numeral 1 denotes a reactive power compensator which is one of power converters, and is connected to a power system (not shown) to supply stable power with little voltage fluctuation to a load which is a demand end. Used. The reactive power compensator 1 includes, for example, a transformer 3 for a multi-transformer that forms an AC side by connecting the primary sides of a three-phase transformer 2 in series, and each secondary side of the transformer 3 for this converter. 6 single-phase bridges 4 using power semiconductor elements such as GTO or IEGT are connected to the phases, and the output side is connected in parallel, the P-side bus 5 of the high-voltage side line, and the N-side bus 6 of the low-voltage side line And a converter 7 constituting the DC side. Further, a capacitor 8 is connected between the P-side bus 5 and the N-side bus 6 of the converter 7.

  Further, a fouling detection device 9 is connected between the P-side bus 5 and the N-side bus 6 so as to be in parallel with the capacitor 8. The fouling detection device 9 includes a high voltage side resistance unit 10, a low voltage side resistance unit 11, and a voltage measurement unit 12. The high voltage side resistance unit 13 and the low voltage side resistance unit 11 of the high voltage side resistance unit 10 are provided. The low voltage side resistor 14 is connected in series, and is connected between the P side bus 5 and the N side bus 6 so as to resistance-divide the PN voltage with a predetermined ratio. The voltage between both ends of the low-voltage side resistor 14, which is one voltage obtained by dividing the voltage between P and N to obtain a voltage that can be taken in, is connected.

  Further, the contamination detection device 9 is different in terms of insulation performance in that the high-voltage side resistor unit 10 and the low-voltage side resistor unit 11 support the insulator that supports the high-voltage side resistor 13 and the low-voltage side resistor 14, respectively. It is structured to be. For example, when an insulator supporting the high-voltage side resistor 13 has a normal level of insulation performance, the insulation performance of the insulator supporting the low-voltage side resistor 14 is affected by surrounding contamination and the insulation performance is lowered. In order to make it easier, the shape itself is easily affected by fouling, or the plates are mounted in parallel so that dust and the like are easily deposited.

  That is, the high-voltage side resistance unit 10 of the fouling detection device 9 includes a high-voltage side resistor 13 having, for example, a substantially rod shape, and a high-voltage side insulating support member 15 made of an insulator or the like. The casing 16 of the reactive power compensator 1 is configured so that both ends are supported by the two high-voltage-side insulating support members 15 with the axial direction thereof being substantially vertical so that the area in the vertical direction is reduced. Are attached to a vertical or substantially vertical wall portion 17 in the vicinity of the P-side bus 5 and the N-side bus 6.

  On the other hand, the low voltage side resistance portion 11 has a rectangular shape having a larger area in the vertical direction than the low voltage side resistance 14, which is also substantially rod-shaped, the low voltage side insulating support member 18 made of insulator or the like, and the low voltage side resistance 14. An insulating mounting plate 19 and an insulating mounting member 20 are included. The insulating mounting plate 19 is supported by the four low-voltage-side insulating support members 18 at each corner so that the corners of the P-side bus 5 and the N-side bus 6 of the casing 16 of the reactive power compensator 1 are horizontal or A substantially horizontal surface, for example, a bottom surface 21 is attached substantially horizontally. Further, the low-voltage side resistor 14 is arranged on the upper surface of the insulating mounting plate 19 so that both ends are supported by the two insulating mounting members 20 so that the area viewed in the vertical direction is larger than that of the high-voltage side resistor 13. Are attached so that the axial direction is substantially horizontal.

  Although the low voltage side resistor 14 is mounted using the insulating mounting member 20 and the insulating mounting plate 19, both ends are supported by the two low voltage side insulating support members 18 in the same manner as the high voltage side resistor 13. In this manner, the reactive power compensator 1 may be attached to the casing 16 so that the axial direction is substantially horizontal.

  In the reactive power compensator 1 including the contamination detection device 9 having such a configuration, the voltage measurement unit 12 of the contamination detection device 9 continues to measure the voltage across the low-voltage side resistor 14 while being used. Then, it is checked whether or not the voltage value is lower than a preset voltage value. By continuing to use for a long period of time, the voltage across the low-voltage resistor 14 becomes equal to or lower than a preset voltage value, and when this is detected, it is provided in the voltage measuring unit 12 or provided in a monitoring room or the like. A notification device or the like (not shown) is notified to notify that an abnormality has occurred.

  That is, when the reactive power compensator 1 is installed and used in a place where the surrounding environment is poor, such as a place with a lot of dust or a place with high humidity, the inside of the casing 16 of the reactive power compensator 1 is also long. Continuing the use causes accumulation of dust and the like, resulting in contamination. Accordingly, the low voltage side resistor 14 is attached so that the area in the vertical direction is larger than that of the high voltage side resistor 13, and the insulating mounting plate 19 is further provided. Accumulation progresses faster.

  As a result, the insulation drop at the low voltage side resistor 14 proceeds faster than the insulation drop at the high voltage side resistor 13 attached substantially vertically, and is lower than the voltage across the high voltage side resistor 13. The voltage across the side resistor 14 will drop quickly. Then, it is detected that the voltage between both ends of the low-voltage side resistor 14 is equal to or lower than a preset voltage value, and it is determined that there is an abnormality and is notified.

  As a result, it can be easily known that the contamination in the casing 16 of the reactive power compensator 1, that is, the vicinity of the P-side bus 5 and the N-side bus 6 of the converter 7 is progressing. The occurrence of an accident such as a DC short circuit between the P-side bus 5 and the N-side bus 6 of the main circuit due to deterioration can be dealt with in advance, and the accident can be prevented beforehand.

  Next, a second embodiment will be described with reference to FIG. FIG. 3 is a schematic configuration diagram of the fouling detection apparatus. Note that the reactive power compensator 1 portion is the same as that of the first embodiment, and the configuration of the high voltage side resistance portion and the low voltage side resistance portion is different. A description of the configuration of this embodiment, which is different from that of the first embodiment, will be described.

  In FIG. 3, reference numeral 25 denotes a fouling detection device, which is connected to the capacitor 8 between the P-side bus 5 and the N-side bus 6 of the reactive power compensator 1, which is one of the power converters, as in the first embodiment. They are connected in parallel. As in the first embodiment, the contamination detection device 25 includes a high voltage side resistor 13 of the high voltage side resistor unit 26 and a low voltage side resistor 14 of the low voltage side resistor unit 27 that are connected in series at a predetermined ratio. Therefore, the voltage across the low-voltage side resistor 14 is connected between the P-side bus 5 and the N-side bus 6 so as to resistively divide the PN voltage. The voltage measuring unit 12 is configured to measure.

  Further, the high-voltage side resistor 26 and the low-voltage side resistor 27 of the fouling detection device 25 are also provided with insulators that support the high-voltage side resistor 13 and the low-voltage side resistor 14, respectively, as in the first embodiment. The structure is such that there is a difference in insulation performance. For example, the support insulator of the high-voltage side resistor 13 is changed to a normal level of insulation performance, and the support insulator of the low-voltage side resistor 14 is affected by the surrounding contamination so that the insulation performance is likely to be lowered. Yes.

  That is, the high-voltage side resistance portion 26 of the fouling detection device 25 includes, for example, a high-voltage side resistance 13 made of, for example, a substantially rod-shaped high-voltage side resistor 13 and an insulator, a rectangular high-voltage side insulation mounting plate 29, An insulating mounting member 30 is included. The high voltage side insulating mounting plate 29 is supported by the four high voltage side insulating support members 28 at each corner so that the vicinity of the P side bus 5 and the N side bus 6 of the casing 16 of the reactive power compensator 1. Are attached to a horizontal or substantially horizontal surface, for example, the bottom surface 21 substantially horizontally. Further, the high voltage side resistor 13 is supported so that both ends thereof are supported by two standing insulating mounting members 30 so that the axial direction is substantially horizontal on the upper surface of the high voltage side insulating mounting plate 29. Is attached. The high voltage side insulating mounting plate 29 has a smaller area when viewed in the vertical direction than the low voltage side insulating mounting plate 31 described later, and dust or the like does not accumulate between the two insulating mounting members 30. An opening 32 is formed.

  On the other hand, the low-voltage side resistor 27 has a larger area in the vertical direction than the low-voltage side resistor 14, which is also substantially rod-shaped, the low-voltage-side insulating support member 33 made of insulator or the like, and the high-voltage-side insulating mounting plate 29. A rectangular low-voltage side insulating mounting plate 31 and an insulating mounting member 34 are included. Then, the low voltage side insulating mounting plate 31 is supported at each corner by four low voltage side insulating support members 33, and the vicinity of the P side bus 5 and the N side bus 6 of the casing 16 of the reactive power compensator 1. Are attached to a horizontal or substantially horizontal surface, for example, the bottom surface 21 substantially horizontally. Further, the low voltage side resistor 14 is supported so that both ends thereof are supported by two standing insulating mounting members 34 so that the axial direction is substantially horizontal on the upper surface of the low voltage side insulating mounting plate 31. Is attached.

  Then, in the reactive power compensator 1 having the contamination detection device 25 having such a configuration, the voltage measurement unit 12 of the contamination detection device 25 uses the low voltage side while using the reactive power compensation device 1 as in the first embodiment. The voltage across the resistor 14 is continuously measured, and a check is made as to whether or not the voltage is less than a preset voltage value. By continuing to use for a long period of time, the voltage across the low-voltage resistor 14 becomes equal to or lower than a preset voltage value, and when this is detected, it is provided in the voltage measuring unit 12 or provided in a monitoring room or the like. A notification device or the like (not shown) is notified to notify that an abnormality has occurred.

  That is, when the reactive power compensator 1 is installed and used in a place where the surrounding environment is poor, such as a place with a lot of dust or a place with high humidity, the inside of the casing 16 of the reactive power compensator 1 is also long. Continuing the use causes accumulation of dust and the like, resulting in contamination. Accordingly, dust or the like is accumulated on the upper surfaces of the high voltage side insulating mounting plate 29 to which the high voltage side resistor 13 is attached and the low voltage side insulating mounting plate 31 to which the low voltage side resistor 14 is attached. However, since the area of the low voltage side insulating mounting plate 31 is larger than that of the high voltage side insulating mounting plate 29, accumulation of dust and the like proceeds faster.

  As a result, the insulation decrease at the low voltage side resistor 14 proceeds faster than the insulation decrease at the high voltage side resistor 13, and the voltage across the low voltage side resistor 14 is higher than the voltage across the high voltage side resistor 13. The voltage will drop quickly. Then, it is detected that the voltage between both ends of the low-voltage side resistor 14 is equal to or lower than a preset voltage value, and it is determined that there is an abnormality and is notified.

  As a result, it is possible to easily know that the contamination in the casing 16 of the reactive power compensator 1 is progressing, and it is possible to prevent the occurrence of an accident such as a DC short-circuit as in the first embodiment. .

  In each of the above embodiments, each of the high-voltage side resistor 13 and the low-voltage side resistor 14 is one. However, the low-voltage side resistor 14 is composed of a plurality of resistors, and the area in the vertical direction is high voltage. By making it larger than the side resistance 13, or by making the area of the low voltage side resistance 14 itself as viewed in the vertical direction larger than that of the high voltage side resistance 13, there is no need to use a mounting plate. May be.

  Furthermore, in the second embodiment, the high-voltage side resistor 26 and the low-voltage side resistor 27 are both mounted on a horizontal plane, but both may be mounted on a vertical surface, or only the high-voltage side resistor 26 may be mounted on a vertical surface. .

1 is a circuit diagram of a reactive power compensator provided with a fouling detection apparatus according to a first embodiment of the present invention. 1 is a schematic configuration diagram of a fouling detection apparatus according to a first embodiment of the present invention. It is a schematic block diagram of the fouling detection apparatus which is the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Reactive power compensation apparatus 5 ... P side bus 6 ... N side bus 10 ... High voltage side resistance part 11 ... Low voltage side resistance part 12 ... Voltage measurement part 13 ... High voltage side resistance 14 ... Low voltage side resistance 16 ... Housing body

Claims (5)

The high voltage side resistance of the high voltage side resistance part and the low voltage side resistance of the low voltage side resistance part provided in the casing of the power converter are connected in series between the DC high voltage side line and the low voltage side line. A contamination detection device for a power converter that detects contamination in the casing by measuring the voltage across the low-voltage side resistor,
A contamination detection device for a power converter, wherein the contamination state in the housing is determined to be abnormal when the voltage at both ends of the low-voltage side resistance becomes a predetermined voltage value or less.   The low-voltage-side resistance unit is installed such that a decrease in both-end voltage due to contamination of the low-voltage-side resistance is greater than a decrease in both-end voltage due to contamination of the high-voltage-side resistance. Item 2. The contamination detection device for a power conversion device according to Item 1.   The contamination detection device for a power converter according to claim 1, wherein the low-voltage side resistance unit is installed at a position where the progression of the contamination progresses faster than the high-voltage side resistance unit.   The low voltage side resistance portion is configured such that the low voltage side resistance is attached to a horizontal surface or a substantially horizontal surface of the housing via an insulating support member, and the high voltage side resistance portion is configured such that the high voltage side resistance is The contamination detection device for a power converter according to claim 3, wherein the device is attached to a vertical or substantially vertical surface of the casing via an insulating support member.   The low voltage side resistance portion and the high voltage side resistance portion are respectively an insulating mounting member on an insulating mounting plate of each resistance portion in which the low voltage side resistance and the high voltage side resistance are insulated and supported by the casing. The area of the insulating mounting plate of the low-voltage-side resistance portion that is damaged is larger than the area of the high-voltage-side resistance portion of the insulating mounting plate that is damaged. Item 3. The contamination detection device for a power conversion device according to Item 2.

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