JPH076641U - Electric water heater - Google Patents
Electric water heaterInfo
- Publication number
- JPH076641U JPH076641U JP3698193U JP3698193U JPH076641U JP H076641 U JPH076641 U JP H076641U JP 3698193 U JP3698193 U JP 3698193U JP 3698193 U JP3698193 U JP 3698193U JP H076641 U JPH076641 U JP H076641U
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- harmonic
- electric
- series
- water heater
- predetermined order
- Prior art date
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Abstract
(57)【要約】
【目的】 一般家庭で用いられる電気温水器を改良する
ことによって、いわば分散されたフィルタリングシステ
ムによって高調波障害を効果的に解消する。
【構成】 タンク10内の水を加熱する複数の電熱器1
1,12を設け、所定次数の高調波において配電系統の
柱上変圧器15と直列共振するコンデンサ13を電熱器
11に直列接続する。
【効果】 所定次数の高調波成分のエネルギーが電熱器
11により消費されることにより、配電系統およびさら
に上位系の所定次数の高調波成分を負荷系において分散
吸収することができる。
(57) [Summary] [Objective] By improving electric water heaters used in ordinary households, harmonic interference is effectively eliminated by a so-called distributed filtering system. [Structure] A plurality of electric heaters 1 for heating water in a tank 10.
1 and 12 are provided, and the capacitor 13 that resonates in series with the pole transformer 15 of the distribution system at a harmonic of a predetermined order is connected in series to the electric heater 11. [Effect] By consuming the energy of the harmonic component of the predetermined order by the electric heater 11, it is possible to disperse and absorb the harmonic component of the predetermined order of the power distribution system and the upper system.
Description
【0001】[0001]
この考案は一般家庭で、例えば深夜電力を利用する電気温水器に係り、特に配 電系統に含まれる高調波成分の抑制に効果のある電気温水器に関する。 The present invention relates to an electric water heater that uses, for example, late-night power in a general household, and particularly to an electric water heater that is effective in suppressing harmonic components included in a distribution system.
【0002】[0002]
近年、都市の電力系統において配電系統に含まれる高調波成分の影響が問題と なっており、特に第5高調波の問題が顕在化している。これは負荷系から発生す る高調波成分のうち第5高調波が最も多く、電力系統の特性が第5高調波に対し て後述するようにクリティカルであることが原因である。 In recent years, the influence of harmonic components contained in the power distribution system has become a problem in electric power systems in cities, and in particular, the problem of the fifth harmonic has become apparent. This is because the 5th harmonic is the largest of the harmonic components generated from the load system, and the characteristics of the power system are critical for the 5th harmonic, as described below.
【0003】 図3は配電系統を模式的に示す回路図である。図3において1は多数の負荷系 が原因となって、即ち全系統から流出する高調波電流により作り上げられた上位 系の高調波電圧源、2は変電所の送り出し用変圧器、3は需要家側の6.6kV の受電部に設けられた直列リアクトル付き進相コンデンサ、5は直列リアクトル なし進相コンデンサである。また、4,6は一般負荷である。直列リアクトル付 き進相コンデンサ3には力率調整用の開閉器が備えられていて、直列リアクトル は開閉制御の際に流れる突入電流を抑制する。また、前記直列リアクトルは高調 波源に対し合成リアクタンスを誘導性として、高調波成分を拡大しないように作 用する。また、このような開閉制御を行わずに常時進相コンデンサを接続してお く場合には、直列リアクトルは通常設けられていない。ところが、このような系 統において、変電所の変圧器2の誘導リアクタンス成分と、需要家側の直列リア クトルのない進相コンデンサおよびケーブル系統の容量リアクタンス成分とが直 列共振に近い状態となれば、6.6kV母線はその歪率を拡大し、その結果、当 該系統に接続されている直列リアクトル付き進相コンデンサに第5高調波の過電 流が流れ、それを焼損させる場合があった。FIG. 3 is a circuit diagram schematically showing a power distribution system. In Fig. 3, 1 is caused by a number of load systems, that is, higher-order harmonic voltage source created by harmonic currents flowing out of the whole system, 2 is a transformer for sending out electric power from a substation, and 3 is a customer. The phase-advancing capacitor with a serial reactor provided in the 6.6 kV power receiving unit on the side is a phase-advancing capacitor without a serial reactor. Further, 4 and 6 are general loads. The phase advancing capacitor 3 with a series reactor is provided with a switch for adjusting the power factor, and the series reactor suppresses the inrush current that flows during the switching control. Further, the series reactor is operated so that the combined reactance is inductive to the harmonic source and the harmonic component is not expanded. Further, when the phase advancing capacitor is always connected without performing such switching control, the series reactor is not normally provided. However, in such a system, the inductive reactance component of the transformer 2 of the substation, the phase-advancing capacitor without the series reactor on the customer side, and the capacitive reactance component of the cable system are close to a series resonance. For example, the distortion factor of the 6.6 kV bus may be increased, and as a result, the 5th harmonic overcurrent may flow into the phase-advancing capacitor with a series reactor connected to the system, causing burnout. It was
【0004】 ここで上位系の高調波成分をEn、拡大後の高調波成分をenとした場合の高 調波拡大率(en/En)を図4に示す。このように高調波拡大率が昼間では比 較的小さく、夜間に大きくなる。これは昼間に投入されている一般負荷が前記直 列共振のQ(共振の急峻度)に対しダンピングファクターとして効くためである 。従って上述の問題は昼間よりむしろ夜間により重大となる。Here, FIG. 4 shows a high harmonic expansion ratio (en / En) when the higher-order harmonic component is En and the expanded harmonic component is en. Thus, the harmonic expansion rate is relatively small in the daytime and large at night. This is because the general load applied in the daytime acts as a damping factor for the Q (resonance steepness) of the series resonance. Therefore, the above-mentioned problems become more serious at night rather than daytime.
【0005】 そこで、このような高調波障害の対応策として一般家電汎用品からの高調波電 流の抑制、特別需要家からの高調波電流の抑制および機器の高調波耐量の向上を 図る指針が示されているが、現状の高調波障害の虞を直ちに改善できるものでは ない。また、L−C回路によって所定の高調波成分に対し低インピーダンス回路 を構成して高調波成分を吸収する高調波フィルター設備、或いは高調波電流を積 極的に注入して所定の高調波成分を吸収するアクティブフィルタ型の高調波フィ ルター設備も利用されるが、これらは何れも不特定の高調波源に対応する方式と しては種々の問題があり、通常は特定負荷に対応する局所的な高調波抑制対策の ために用いられている。Therefore, as countermeasures against such harmonic interference, guidelines for suppressing harmonic current from general-purpose household appliances, suppressing harmonic current from special customers, and improving harmonic withstand capability of equipment are provided. However, it is not possible to immediately improve the current fear of harmonic interference. In addition, the LC circuit forms a low-impedance circuit for the specified harmonic component, and the harmonic filter equipment absorbs the harmonic component, or the harmonic current is positively injected to generate the specified harmonic component. Active filter type harmonic filter equipment that absorbs is also used, but all of these have various problems as methods for dealing with unspecified harmonic sources, and usually there are local problems that correspond to specific loads. It is used as a harmonic suppression measure.
【0006】 この考案の目的は、上述した背景に鑑み成されたものであり、一般家庭で用い られる電気温水器を改良することによって、いわば分散されたフィルタリングシ ステムによって高調波障害を効果的に解消するものである。The object of the present invention was made in view of the above-mentioned background, and by improving an electric water heater used in a general household, it is possible to effectively prevent harmonic interference by a distributed filtering system. It will be resolved.
【0007】[0007]
この考案の電気温水器は、タンク内の水を加熱する複数の電熱器をそれぞれ商 用電源の負荷として設けるとともに、商用電源周波数の所定次数の高調波におい て配電系統の柱上変圧器と直列共振するコンデンサを前記複数の電熱器のうちの 少なくとも一つの電熱器に対し直列に接続したことを特徴とする。 The electric water heater of the present invention is provided with a plurality of electric heaters for heating the water in the tank as the loads of the commercial power source, and in series with the pole transformer of the distribution system at the harmonics of the predetermined order of the commercial power frequency. A resonating capacitor is connected in series to at least one electric heater among the plurality of electric heaters.
【0008】[0008]
この考案の電気温水器では、タンク内の水を加熱する電熱器が複数設けられて いて、複数の電熱器のうち少なくとも一つの電熱器に、商用電源周波数の所定次 数の高調波において配電系統の柱上変圧器と共振するコンデンサが直列に接続さ れている。このように構成したことにより、配電系統の柱上変圧器と前記コンデ ンサとは所定次数の高調波の周波数で直列共振し、所定次数の高調波に対して低 インピーダンス回路を構成する。これにより所定次数の高調波成分が前記コンデ ンサに直列接続されている電熱器により電力消費されることになる。その結果、 高調波成分の移行先である柱上変圧器の一次側(例えば6.6kV母線)の所定 次数の高調波成分が吸収される。この考案の電気温水器が多くの一般家庭で用い られるようになると、負荷系において分散された多数の点で所定次数の高調波が 吸収されることになる。このように、高調波発生源である負荷系で高調波成分が 分散吸収され、これにより高調波成分の移行先である上位系での高調波成分が抑 制されることにより、その相乗効果によって電力系全体の所定次数の高調波が効 果的に抑制される。特にこの電気温水器を深夜電力温水器として用いれば、夜間 において従来拡大されていた所定次数の高調波成分が抑制され、高調波障害が効 果的に防止される。 The electric water heater of the present invention is provided with a plurality of electric heaters for heating the water in the tank, and at least one electric heater of the plurality of electric heaters is provided with a distribution system at a harmonic of a predetermined order of the commercial power frequency. A pole transformer and a capacitor that resonate are connected in series. With this configuration, the pole transformer of the distribution system and the capacitor resonate in series at the frequency of the harmonic of the predetermined order, and a low impedance circuit is configured for the harmonic of the predetermined order. As a result, the harmonic component of the predetermined order is consumed by the electric heater connected in series with the capacitor. As a result, the harmonic components of a predetermined order on the primary side (for example, 6.6 kV bus bar) of the pole transformer to which the harmonic components are transferred are absorbed. When the electric water heater of the present invention comes to be used in many ordinary households, the harmonics of a predetermined order are absorbed at many points distributed in the load system. In this way, the harmonic components are dispersed and absorbed in the load system that is the harmonic generation source, and as a result, the harmonic components in the upper system that is the transition destination of the harmonic components are suppressed. The harmonics of a predetermined order in the entire power system are effectively suppressed. In particular, if this electric water heater is used as a midnight power water heater, the harmonic components of a predetermined order, which had been conventionally expanded at night, are suppressed, and harmonic interference is effectively prevented.
【0009】[0009]
この考案の実施例である電気温水器の構成を図2に示す。図2において10は 貯湯タンク、11,12はそれぞれ貯湯タンク10内の水(湯)を加熱する電熱 器である。また13は電熱器11と直列接続されて、第5高調波の周波数で配電 系統の柱上変圧器と直列共振するコンデンサである。 The structure of the electric water heater which is an embodiment of the present invention is shown in FIG. In FIG. 2, 10 is a hot water storage tank, and 11 and 12 are electric heaters that heat the water (hot water) in the hot water storage tank 10, respectively. Reference numeral 13 is a capacitor that is connected in series with the electric heater 11 and that resonates in series with the pole transformer of the distribution system at the frequency of the fifth harmonic.
【0010】 図1は図2に示した電気温水器が接続される電力系統の構成を示す図である。FIG. 1 is a diagram showing a configuration of an electric power system to which the electric water heater shown in FIG. 2 is connected.
【0011】 図1において16は、この例では77kVを6.6kVに変圧する変電所におけ る主変圧器、15は6.6kV母線から分岐された配電線に接続され、一般家庭 に200Vを供給する柱上変圧器である。そして需要家(一般家庭)において、 電力量計14を介して図2に示した電気温水器が接続されている。この構成にお いて、電気温水器に設けたコンデンサ13は柱上変圧器15のリアクタンス成分 (実質上%インピーダンス)と第5高調波において直列共振する。従って第5高 調波成分については柱上変圧器15のインピーダンスはほぼ0となって、第5高 調波成分は電熱器11により消費されることになる。これにより、6.6kV母 線から分岐された配電線の第5高調波エネルギーは柱上変圧器15を介して負荷 に吸収され、6.6kV母線およびその上位系である77kV系の第5高調波成 分が抑制される。基本波成分および第5高調波を除くその他の高調波成分につい ては電熱器12により消費される。例えば柱上変圧器15の2次側に5%の第5 高調波が含まれている場合、柱上変圧器15の2次側換算で第5高調波成分は1 0Vであるため、電熱器11の抵抗値を1Ωとすれば電熱器11に10Aが流れ 、電熱器11によって第5高調波が100W消費されることになる。このように 、コンデンサ13の容量は第5高調波において柱上変圧器と直列共振するように 選択し、電熱器11の抵抗値は系統に含まれる第5高調波成分の歪率(背後の歪 率)と柱上変圧器15の容量を考慮して定める。In FIG. 1, reference numeral 16 is a main transformer in a substation that transforms 77 kV to 6.6 kV in this example, and 15 is connected to a distribution line branched from a 6.6 kV bus bar to supply 200 V to a general household. It is a pole transformer to supply. Then, in the consumer (general household), the electric water heater shown in FIG. 2 is connected via the electricity meter 14. In this configuration, the capacitor 13 provided in the electric water heater resonates in series with the reactance component (substantially% impedance) of the pole transformer 15 at the fifth harmonic. Therefore, for the fifth harmonic component, the impedance of the pole transformer 15 becomes almost 0, and the fifth harmonic component is consumed by the electric heater 11. As a result, the fifth harmonic energy of the distribution line branched from the 6.6 kV bus is absorbed by the load via the pole transformer 15, and the 6.6 kV bus and the higher harmonic of the 77 kV system, which is the upper system, are absorbed. Wave components are suppressed. The harmonic components other than the fundamental wave component and the fifth harmonic component are consumed by the electric heater 12. For example, if the secondary side of the pole transformer 15 contains 5% of the fifth harmonic, the fifth harmonic component is 10 V in terms of the secondary side of the pole transformer 15, so the electric heater If the resistance value of 11 is set to 1Ω, 10 A flows to the electric heater 11, and the electric heater 11 consumes 100 W of the fifth harmonic. In this way, the capacitance of the capacitor 13 is selected so as to resonate in series with the pole transformer at the fifth harmonic, and the resistance value of the electric heater 11 is set to the distortion factor of the fifth harmonic component (back distortion Rate) and the capacity of the pole transformer 15 are taken into consideration.
【0012】 なお、実施例では第5高調波成分の消費用の電熱器11とその他の通常の電熱 器12のみを並列に配置した例を示したが、電熱器11に消費される電力は、背 後の歪率によって大きく左右されるため、必要とする発熱量、または消費電力の 上限などを考慮して、第5高調波成分の電力を消費する電熱器11の実際の電力 消費量に応じて、他の通常の電熱器12による電力消費を調整するようにしても よい。例えば、コンデンサを接続しない通常の電熱器を複数個設けておき、その 接続状態の切り換えによって、全体の電力消費量を必要量に制御するように構成 すればよい。In the embodiment, only the electric heater 11 for consuming the fifth harmonic component and the other normal electric heater 12 are arranged in parallel, but the electric power consumed by the electric heater 11 is Since it is greatly affected by the back distortion rate, the actual heat consumption of the electric heater 11 that consumes the power of the fifth harmonic component should be considered, considering the required heat generation amount or the upper limit of power consumption. Then, the power consumption by another normal electric heater 12 may be adjusted. For example, a plurality of normal electric heaters to which capacitors are not connected may be provided, and the total power consumption may be controlled to the required amount by switching the connection state.
【0013】[0013]
この考案によれば次のような効果を奏する。 According to this invention, the following effects are achieved.
【0014】 (1)所定の高調波成分を抑制するだけでなく、その高調波成分のエネルギー を熱エネルギーとして回収できるため、電力の有効利用が図れる。(1) Not only can a predetermined harmonic component be suppressed, but the energy of the harmonic component can be recovered as heat energy, so that electric power can be effectively used.
【0015】 (2)本願考案の電気温水器が多くの一般家庭で利用されることによって、多 くの高調波フィルタが電力系統に分散配置されることになり、高調波成分の分散 的なフィルタリングシステムが実現できる。(2) Since the electric water heater of the present invention is used in many ordinary households, many harmonic filters are distributed and arranged in the power system, and the harmonic components are dispersively filtered. The system can be realized.
【0016】 (3)高調波障害の原因となる高調波成分をその発生源の近傍において分散吸 収することによって、負荷系の高調波成分を抑制するとともに、高調波成分の移 行先である上位系の高調波成分を抑制し、背後の歪率を低減するようにしたため 、相乗効果によって電力系全体の所定次数の高調波を効果的に抑制することがで きる。(3) The harmonic component of the load system is suppressed by dispersing and absorbing the harmonic component that causes the harmonic interference in the vicinity of the source, and the higher-order component, which is the destination of the harmonic component, is absorbed. Since the harmonic components of the system are suppressed and the distortion factor behind is reduced, the harmonics of a predetermined order of the entire power system can be effectively suppressed by the synergistic effect.
【0017】 (4)この考案の電気温水器が深夜電力温水器として用いられることによって 、当該電気温水器が、直列リアクトルなしの進相コンデンサと変圧器との直列共 振を抑えるダンピング回路として働き、夜間における高調波成分の拡大率が抑制 される。(4) By using the electric water heater of the present invention as a midnight power water heater, the electric water heater functions as a damping circuit that suppresses series resonance between a phase advancing capacitor without a series reactor and a transformer. The expansion rate of harmonic components at night is suppressed.
【図1】この考案の実施例である電気温水器を含む電力
系統の構成を示す図である。FIG. 1 is a diagram showing a configuration of an electric power system including an electric water heater which is an embodiment of the present invention.
【図2】この考案の実施例である電気温水器の構成を示
す図である。FIG. 2 is a diagram showing a configuration of an electric water heater which is an embodiment of the present invention.
【図3】配電系統の構成例を示す図である。FIG. 3 is a diagram illustrating a configuration example of a power distribution system.
【図4】夜間と昼間における高調波成分の拡大率の関係
を示す図である。FIG. 4 is a diagram showing a relationship between a magnifying power of a harmonic component at night and in a daytime.
1−高調波電圧源 2−変圧器 3−直列リアクトル付き進相コンデンサ 4,6− 一般負荷 5−直列リアクトルなし進相コンデンサ 10−タンク 11,12−電熱器 13−コンデンサ 14−電力量計 1-Harmonic voltage source 2-Transformer 3-Advancing capacitor with series reactor 4,6-General load 5-Advancing capacitor without series reactor 10-Tank 11,12-Electric heater 13-Capacitor 14-Electricity meter
Claims (1)
それぞれ商用電源の負荷として設けるとともに、商用電
源周波数の所定次数の高調波において配電系統の柱上変
圧器と直列共振するコンデンサを前記複数の電熱器のう
ちの少なくとも一つの電熱器に対し直列に接続したこと
を特徴とする電気温水器。1. A plurality of electric heaters for heating water in a tank are respectively provided as loads of a commercial power supply, and a capacitor that resonates in series with a pole transformer of a distribution system at a harmonic of a predetermined order of the commercial power supply frequency is provided. An electric water heater connected in series to at least one electric heater of a plurality of electric heaters.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3698193U JP2580118Y2 (en) | 1993-07-06 | 1993-07-06 | Electric water heater |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3698193U JP2580118Y2 (en) | 1993-07-06 | 1993-07-06 | Electric water heater |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH076641U true JPH076641U (en) | 1995-01-31 |
JP2580118Y2 JP2580118Y2 (en) | 1998-09-03 |
Family
ID=12484935
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3698193U Expired - Fee Related JP2580118Y2 (en) | 1993-07-06 | 1993-07-06 | Electric water heater |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2580118Y2 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5313751A (en) * | 1976-07-21 | 1978-02-07 | Kyokuto Kaihatsu Kogyo Co Ltd | Wire retricting device for winch |
JPS5756683U (en) * | 1980-09-20 | 1982-04-02 | ||
JPH0272818A (en) * | 1988-09-07 | 1990-03-13 | Daiwa Seiko Inc | Level winding apparatus for fishing reel |
JP2020503699A (en) * | 2016-12-21 | 2020-01-30 | ネグレッテ・ヘルナンデス、ホアキン・エンリケNEGRETE HERNANDEZ,Joaquin Enrique | Harmonic filter using semi-magnetic bobbin |
JP2020191731A (en) * | 2019-05-22 | 2020-11-26 | 日新電機株式会社 | Harmonic filter device |
-
1993
- 1993-07-06 JP JP3698193U patent/JP2580118Y2/en not_active Expired - Fee Related
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5313751A (en) * | 1976-07-21 | 1978-02-07 | Kyokuto Kaihatsu Kogyo Co Ltd | Wire retricting device for winch |
JPS5649836B2 (en) * | 1976-07-21 | 1981-11-25 | ||
JPS5756683U (en) * | 1980-09-20 | 1982-04-02 | ||
JPS6232235Y2 (en) * | 1980-09-20 | 1987-08-18 | ||
JPH0272818A (en) * | 1988-09-07 | 1990-03-13 | Daiwa Seiko Inc | Level winding apparatus for fishing reel |
JP2020503699A (en) * | 2016-12-21 | 2020-01-30 | ネグレッテ・ヘルナンデス、ホアキン・エンリケNEGRETE HERNANDEZ,Joaquin Enrique | Harmonic filter using semi-magnetic bobbin |
JP2022033814A (en) * | 2016-12-21 | 2022-03-02 | ネグレッテ・ヘルナンデス、ホアキン・エンリケ | Harmonic filter using semi-magnetic bobbin |
JP2020191731A (en) * | 2019-05-22 | 2020-11-26 | 日新電機株式会社 | Harmonic filter device |
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