JPH07109424B2 - Digital power meter - Google Patents
Digital power meterInfo
- Publication number
- JPH07109424B2 JPH07109424B2 JP1246787A JP24678789A JPH07109424B2 JP H07109424 B2 JPH07109424 B2 JP H07109424B2 JP 1246787 A JP1246787 A JP 1246787A JP 24678789 A JP24678789 A JP 24678789A JP H07109424 B2 JPH07109424 B2 JP H07109424B2
- Authority
- JP
- Japan
- Prior art keywords
- power
- signal
- current
- cosφ
- voltage
- 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.)
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R21/00—Arrangements for measuring electric power or power factor
- G01R21/133—Arrangements for measuring electric power or power factor by using digital technique
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Emergency Protection Circuit Devices (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明はデジタル電力計測器に係り、特に、信号伝送路
の電力を精度よく計測するに好適なデジタル電極計測器
に関する。TECHNICAL FIELD The present invention relates to a digital power measuring instrument, and more particularly to a digital electrode measuring instrument suitable for accurately measuring the power of a signal transmission path.
従来、電極系統の電力を計測する場合、電力系の電圧を
計測用変圧器により検出し、電流を変流器により検出
し、各検出信号をフィルタ、サンプルホード回路を介し
てデジタル信号に変換し、このデジタル信号をマルチプ
レクサを介してマイクロプロセッサに供給し、マイクロ
プロセッサにおいて一定周期ごとに電圧、電流の瞬時値
データから有効電力及び無効電力を算出する構成が採用
されている。Conventionally, when measuring the power of the electrode system, the voltage of the power system is detected by a measuring transformer, the current is detected by a current transformer, and each detection signal is converted to a digital signal via a filter and sample-hold circuit. The digital signal is supplied to a microprocessor through a multiplexer, and the microprocessor calculates active power and reactive power from voltage and current instantaneous value data at regular intervals.
〔発明が解決しようとする課題〕 上記従来技術においては、計測用変圧器及び変流器の位
相誤差について配慮がされておらず、変圧器及び変流器
に位相誤差が存在した場合、検出した電圧及び電流から
電力を算出しても、算出した電力と真の電力との間に誤
差が生じるという不具合があった。すなわち、有効電力
Ｐは電圧の実効値Ｖと電流の実効値Ｉと両者の力率cos
θを用いて、Ｐ＝VIcosθとして算出することができる
が、計測用変圧器及び変流器に、変圧器の入出力間の位
相差と変流器の入出力間の位相差の総和を示す位相誤差
φが存在した場合の有効電力Ｐ′はＰ′＝VIcos（θ＋
φ）として算出される。有効電力Ｐ′は真の有効電力Ｐ
よりも力率がcosφだけ変化した値として算出されるこ
とになる。算出した電力Ｐ′を真の有効電力Ｐに近似さ
れるには、位相誤差φを小さくすることによって可能と
なるが、位相誤差φを小さくするには、計測用変圧器戦
び電流器のコア、巻線の材質を変更したり、寸法を変え
たりしなければならず、生産コストが高くなると共に外
形寸法が拡大されるという不具合が生じる。なお、この
種の技術に関連するものとして、特開昭60−205377号公
報、実開昭57−29864号公報に記載されたものがある
が、これらの技術を単に採用しても、真の有効電力と無
効電力を精度よく算出するには十分ではない。[Problems to be Solved by the Invention] In the above-mentioned conventional technology, no consideration is given to the phase error of the measuring transformer and the current transformer, and if there is a phase error in the transformer and the current transformer, it is detected. Even if the electric power is calculated from the voltage and the current, an error occurs between the calculated electric power and the true electric power. That is, the effective power P is the effective value V of the voltage, the effective value I of the current, and the power factor cos of both.
Although θ can be calculated as P = VIcosθ, the sum of the phase difference between the input and output of the transformer and the phase difference between the input and output of the current transformer is shown for the measuring transformer and current transformer. The active power P ′ when there is a phase error φ is P ′ = VIcos (θ +
φ). Active power P'is true active power P
Will be calculated as a value in which the power factor changes by cosφ. The calculated power P ′ can be approximated to the true active power P by reducing the phase error φ. However, to reduce the phase error φ, the core of the measuring transformer and the current transformer can be reduced. Since the material of the winding must be changed and the dimensions must be changed, the production cost becomes high and the external dimensions are enlarged. Incidentally, as those related to this type of technology, there are those described in JP-A-60-205377 and JP-A-57-29864, but even if these technologies are simply adopted, the true It is not enough to accurately calculate active power and reactive power.
本発明の目的は、信号伝送路の電気量を検出する検出手
段に位相誤差が生じても、電気量を検出する検出手段の
検出出力から真の有効電力と無効電力を求めることがで
きるデジタル電力計測器を提供することにある。An object of the present invention is to provide a digital power capable of obtaining true active power and reactive power from the detection output of the detecting means for detecting the electric quantity even if a phase error occurs in the detecting means for detecting the electric quantity of the signal transmission path. To provide a measuring instrument.
前記目的を達成するために、本発明は、信号伝送路の電
圧を検出する電圧検出手段と、信号伝送路の電流を検出
する電流検出手段と、前記両検出手段の検出による瞬時
値をそれぞれ順次デジタル信号に変換する信号変換手段
と、信号変換手段の各出力信号から一定周期の有効電力
Ｐ′と無効電力Ｑ′を算出する第１電力算出手段と、信
号検出時における電圧検出手段と電流検出手段の各入出
力間の位相差の総和を示す位相誤差φに従った補正値co
sφ,sinφを記憶する記憶手段と、第１電力算出手段の
各算出電力Ｐ′,Q′に対する補正値として記憶手段に記
憶された補正値cosφ,sinφを用い、真の有効電力Ｐを
Ｐ＝Ｐ′cosφ＋Ｑ′sinφ、真の有効電力Ｑ′をＱ′＝
Ｑ′cosφ−Ｐ′sinφにより算出する第２電力算出手段
とを有するデジタル電力計測器を構成したものである。In order to achieve the above-mentioned object, the present invention has a voltage detecting means for detecting a voltage of a signal transmission path, a current detecting means for detecting a current of a signal transmission path, and an instantaneous value detected by the both detecting means, respectively. Signal converting means for converting to a digital signal, first power calculating means for calculating active power P'and reactive power Q'of a constant cycle from each output signal of the signal converting means, voltage detecting means and current detecting at the time of signal detection. The correction value co according to the phase error φ indicating the sum of the phase differences between the input and output of the means.
Using the storage means for storing sφ, sinφ and the correction value cosφ, sinφ stored in the storage means as the correction value for each calculated power P ′, Q ′ of the first power calculation means, the true active power P is P = P′cosφ + Q′sinφ, the true active power Q ′ is Q ′ =
A digital power measuring instrument having a second power calculating means for calculating by Q'cosφ-P'sinφ.
まず、電圧検出手段及び電流検出手段の検出出力から位
相誤差を含む有効電力と無効電力を算出し、この算出し
た電力を位相誤差を基に補正する。この補正値として、
位相誤差を含む有効電力及び無効電力から位相誤差分の
力率を除去するものを用いると、補正演算によって真の
有効電力と無効電力を求めることができる。First, active power and reactive power including a phase error are calculated from the detection outputs of the voltage detection means and the current detection means, and the calculated power is corrected based on the phase error. As this correction value,
If the power factor corresponding to the phase error is removed from the active power and the reactive power including the phase error, the true active power and the reactive power can be obtained by the correction calculation.
ここで、信号伝送路の電圧をV,電流をI,電圧検出手段と
電流検出手段の位相誤差をφ、電圧Ｖと電流Ｉの実際の
位相差をθ、位相誤差φを含む有効電力をＰ′，無効電
力をＱ′とすると、有効電力Ｐ′と無効電力Ｑ′は次の
（１）、（２）式によって表される。Here, the voltage of the signal transmission line is V, the current is I, the phase error between the voltage detecting means and the current detecting means is φ, the actual phase difference between the voltage V and the current I is θ, and the active power including the phase error φ is P. ′, And the reactive power is Q ′, the active power P ′ and the reactive power Q ′ are expressed by the following equations (1) and (2).
Ｐ′＝Ｖ・Icos（θ＋φ） ……（１） Ｑ′＝Ｖ・Isin（θ＋φ） ……（２） 次に、位相誤差φを基にした補正値をcosφ、sinφと
し、これらの補正値を基に次の（３）式に示される演算
式を基に有効電力Ｐ′と無効電力Ｑ′を補正すると、真
の有効電力Ｐが得られる。P ′ = V · Icos (θ + φ) (1) Q ′ = V · Isin (θ + φ) (2) Next, the correction values based on the phase error φ are set to cosφ and sinφ, and these correction values By correcting the active power P ′ and the reactive power Q ′ based on the arithmetic expression shown in the following equation (3), the true active power P can be obtained.
Ｐ＝Ｐ′cosφ＋Ｑ′sinφ ……（３） ＝Ｖ・Icos（θ＋φ）・cosφ ＋Ｖ・Isin（θ＋φ）sinφ ＝Ｖ・Ｉ｛cosφ・cos2φ−sinφsinφ・cosφ ＋sinθ・cosφ・sinφ＋cosθ・sin2φ｝ ＝Ｖ・Ｉ（cos2φ・cosθ＋sin2φcosθ） ＝Ｖ・Icosθ（cos2φ＋sin2φ） ＝Ｖ・Icosθ 同様にして、次の（４）式に示される演算を実行する
と、真の無効電力Ｑを算出すことができる。P = P'cosφ + Q'sinφ (3) = V ・ Icos (θ + φ) ・ cosφ + V ・ Isin (θ + φ) sinφ = V ・ I {cosφ ・ cos 2 φ-sinφsinφ ・ cosφ + sinθ ・ cosφ ・ sinφ + cosθ ・ sin 2 φ} = V · I (cos 2 φ · cos θ + sin 2 φcos θ) = V · Icos θ (cos 2 φ + sin 2 φ) = V · I cosθ Similarly, when the operation shown in the following formula (4) is executed, The reactive power Q can be calculated.
Ｑ＝Ｑ′cosφ＋Ｐ′sinφ ……（４） ＝Ｖ・Isin（θ＋φ）・cosφ −Ｖ・Icos（θ＋φ）sinφ ＝Ｖ・Ｉ｛sinθ・cos2φ−cosθsinφ・cosφ −cosθ・cosφ・sinφ＋sinθ・sin2φ｝ ＝Ｖ・Ｉ（cos2φ・sinθ＋sin2φsinθ） ＝Ｖ・Isinθ（cos2φ＋sin2φ） ＝Ｖ・Isinθ 〔実施例〕 以下、本発明の一実施例を図面に基づいて説明する。Q = Q'cosφ + P'sinφ …… (4) = V ・ Isin (θ + φ) ・ cosφ-V ・ Icos (θ + φ) sinφ = V ・ I {sinθ ・ cos 2 φ-cosθsinφ ・ cosφ-cosθ ・ cosφ ・ sinφ + sinθ ・sin 2 φ} = V · I (cos 2 φ · sin θ + sin 2 φsin θ) = V · I sin θ (cos 2 φ + sin 2 φ) = V · I sin θ [Example] An example of the present invention will be described below with reference to the drawings. To do.
第１図において、デジタル電力計測器が信号検出部10、
入力変換部12、演算処理部14、メモリ16、表示部18を備
え、入力変換部12と演算処理部14、メモリ16、表示部18
がバスライン20を介して接続されている。In FIG. 1, the digital power meter is a signal detector 10,
The input conversion unit 12, the arithmetic processing unit 14, the memory 16, and the display unit 18 are provided, and the input conversion unit 12, the arithmetic processing unit 14, the memory 16, and the display unit 18 are included.
Are connected via a bus line 20.
信号検出部10は計測用変流器24と計測用変圧器26から構
成されており、変流器24は電力系の信号伝送路22の電流
を検出する電圧検出手段として構成され、変圧器26は信
号伝送路22の電圧を検出する電圧検出手段として構成さ
れている。そして各変流器24、変圧器26の検出信号が入
力変換部12へ供給されるようになっている。入力変換部
12は高調波を除去するためのフィルタ及びサンプリング
ホールド回路を備えており、変流器24からの電流信号及
び変圧器26からの電圧信号を一定のサンプリング周期、
例えば電気角で30゜ごとにサンプリングし、１周期で12
のサンプリング値をデジタルの電圧信号及びデジタルの
電流信号に変換する信号変換手段として構成されてい
る。そして入力変換部12から出力される電流、電圧の瞬
時値データは、第２図に示されるように、メモリ16の所
定のエリアに順次格納される。このメモリ16には変流器
24および変圧器26の位相誤差φのデータも格納されるよ
うになっている。The signal detecting unit 10 is composed of a measuring current transformer 24 and a measuring transformer 26, and the current transformer 24 is configured as a voltage detecting means for detecting the current of the signal transmission path 22 of the electric power system. Is configured as voltage detection means for detecting the voltage of the signal transmission path 22. The detection signals of the current transformers 24 and the transformers 26 are supplied to the input conversion unit 12. Input converter
12 includes a filter and a sampling and holding circuit for removing harmonics, and a current signal from the current transformer 24 and a voltage signal from the transformer 26 have a constant sampling period,
For example, sampling every 30 ° in electrical angle, 12 in one cycle
Is configured as a signal conversion unit that converts the sampling value of 1 to a digital voltage signal and a digital current signal. The current and voltage instantaneous value data output from the input converter 12 are sequentially stored in a predetermined area of the memory 16 as shown in FIG. This memory 16 has a current transformer
The data of the phase error φ of the transformer 24 and the transformer 26 are also stored.
この位相誤差φは、第３図に示されるように、変圧器26
の入出力間の位相差をφ１とし、変流器24の入出力間の
位相差をφ２とした場合、位相誤差φは位相差φ１と位
相差φ２の総和として表せる。This phase error φ, as shown in FIG.
When the phase difference between the input and output of the current transformer is φ 1 and the phase difference between the input and output of the current transformer 24 is φ 2 , the phase error φ can be expressed as the sum of the phase difference φ 1 and the phase difference φ 2 .
この位相誤差φを予めメモリ16に格納するに際しては、
変流器24及び変圧器26に力率cosθ＝１の電圧信号及び
電流信号を入力し、変流器24及び変圧器26の出力信号を
基に演算処理部14において有効電力P1、無効電力Q1を算
出する。このとき有効電力P1はP1＝Ｖ・Icosφ、無効電
力Q1はQ1＝Ｖ・Isinφとして表わされるため、理論上の
真の有効電力Ｐ、無効電力Ｑと算出した有効電力P1、無
効電力Q1との比から位相誤差φを求めることができる。
更にこの位相誤差φから補正値としてcosφ及びsinφを
メモリ16に記憶しておけば、電力の算出演算を円滑にお
こなうことができる。When storing this phase error φ in the memory 16 in advance,
A voltage signal and a current signal with a power factor cos θ = 1 are input to the current transformer 24 and the transformer 26, and the active power P 1 and the reactive power are calculated in the arithmetic processing unit 14 based on the output signals of the current transformer 24 and the transformer 26. Calculate Q 1 . At this time, the active power P 1 is expressed as P 1 = V · Icosφ, and the reactive power Q 1 is expressed as Q 1 = V · Isinφ. Therefore, theoretical true active power P and reactive power Q are calculated as active power P 1 , The phase error φ can be obtained from the ratio with the reactive power Q 1 .
Further, if cosφ and sinφ are stored in the memory 16 as correction values based on this phase error φ, the calculation calculation of power can be smoothly performed.
演算処理部14はマイクロプロセッサなどで構成されてお
り、処理プログラム及びメモリ16に格納されたデータを
基に各種の演算をおこない、演算結果を表示部18に出力
するようになっている。表示部18は演算処理部14からの
処理結果を画像表示するようになっている。The arithmetic processing unit 14 is configured by a microprocessor or the like, and performs various arithmetic operations based on the processing program and the data stored in the memory 16 and outputs the arithmetic result to the display unit 18. The display unit 18 is configured to display the processing result from the arithmetic processing unit 14 as an image.
本実施例は以上の構成からなり、次にその作用をフロー
チャートに基づいて説明する。The present embodiment has the above configuration, and its operation will be described below with reference to a flowchart.
まず、変流器24及び変圧器26の出力信号を順次取り込
み、電圧、電流の瞬時値データを入力する（ステップ10
0）。このとき１周期分の電圧電流の瞬時値が12点順次
メモリ16に格納される。そしてこれらのデータを基に位
相誤差を含む有効電力Ｐ′、無効電力Ｑ′を算出する
（ステップ102）。この場合有効電力Ｐ′、無効電力
Ｑ′は１周期分の電圧、電流の瞬時値データから次の
（５），（６）式に従って算出される。First, the output signals of the current transformer 24 and the transformer 26 are sequentially captured, and the instantaneous value data of voltage and current are input (step 10
0). At this time, the instantaneous value of the voltage / current for one cycle is sequentially stored in the 12-point memory 16. Then, based on these data, the active power P'and the reactive power Q'including the phase error are calculated (step 102). In this case, the active power P ′ and the reactive power Q ′ are calculated according to the following equations (5) and (6) from the instantaneous value data of the voltage and current for one cycle.
このステップで算出された有効電力Ｐ′、無効電力Ｑ′
は前移した（１），（２）式として表わされる。 Active power P ′ and reactive power Q ′ calculated in this step
Is expressed as the forward equations (1) and (2).
次に、メモリ16に格納された位相誤差φを基に補正値co
sφ、sinφを算出する（ステップ４）。そして、これら
補正値cosφ、sinφを用いて有効電力Ｐ′、無効電力
Ｑ′を補正すると、前述した（３），（４）式から真の
有効電力Ｐ、無効電力Ｑを算出することができる。すな
わち演算処理部14はメモリ16に格納されたデータを基に
有効電力と無効電力を算出する電力算出手段として構成
されている。Next, based on the phase error φ stored in the memory 16, the correction value co
sφ and sinφ are calculated (step 4). Then, when the active power P ′ and the reactive power Q ′ are corrected using these correction values cosφ and sinφ, the true active power P and the reactive power Q can be calculated from the equations (3) and (4) described above. . That is, the arithmetic processing unit 14 is configured as a power calculation unit that calculates active power and reactive power based on the data stored in the memory 16.
演算処理部14において真の有効電力Ｐ、無効電力Ｑが算
出されると、この算出結果が表示部18に転送され、真の
有効電力Ｐと無効電力Ｑの値が画像表示される。そして
各処理演算は一定周期ごとにおこなわれ、各周期の電力
値が表示部18に画像表示される。When the true active power P and the reactive power Q are calculated in the arithmetic processing unit 14, the calculation results are transferred to the display unit 18, and the values of the true active power P and the reactive power Q are displayed as an image. Then, each processing calculation is performed every fixed period, and the power value of each period is displayed as an image on the display unit 18.
また、変圧器26の出力側に位相差φ１と逆位相になるシ
フト量で入力信号の位相をシフトする電圧用移相手段を
設けると共に、変流器24の出力側に位相差φ２と逆位相
になるシフト量で入力信号の位相をシフトする電圧用移
相手段を設け、各移相手段の出力信号を入力変換部12を
介して演算部14へ供給するようにすれば、変流器24及び
変圧器の位相誤差が位相手段によって補正される。この
ため、算出した有効電力及び無効電力を位相誤差φによ
って補正しなくても、算出した有効電力と無効電力を真
の有効電力、無効電力として用いることができる。Further, a voltage phase shifting means for shifting the phase of the input signal by a shift amount that is opposite to the phase difference φ 1 is provided on the output side of the transformer 26, and the phase difference φ 2 is provided on the output side of the current transformer 24. If voltage phase shifting means for shifting the phase of the input signal by the amount of shift to be the opposite phase is provided and the output signal of each phase shifting means is supplied to the calculating section 14 via the input converting section 12, the current transformation occurs. The phase error of the transformer 24 and the transformer is corrected by the phase means. For this reason, the calculated active power and reactive power can be used as true active power and reactive power without correcting the calculated active power and reactive power by the phase error φ.
以上説明したように、本発明によれば、信号伝送路の電
気量を検出する電気量検出手段に位相誤差があっても真
の有効電力及び無効電力を算出することができ、電力供
給側と消費側との電力値を一致させることが可能とな
り、電力消費側で電力料金の管理を容易におこなうこと
ができる。As described above, according to the present invention, the true active power and the reactive power can be calculated even if there is a phase error in the electric quantity detection means for detecting the electric quantity of the signal transmission line, and the electric power supply side It is possible to match the power value with the power consumption side, and the power consumption side can easily manage the power charge.
第１図は本発明の一実施例を示す構成図、第２図はメモ
リの構成説明図、第３図は変流器及び変圧器の入出力波
形図、第４図は第１図に示す計測器の作用を説明するた
めのフローチャートである。 10……信号検出部、12……入力変換部、 14……演算処理部、16……メモリ、 18……表示部、20……バスライン、 22……信号伝送路、24……変流器、 26……変圧器。FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a memory block diagram, FIG. 3 is an input / output waveform diagram of a current transformer and a transformer, and FIG. 4 is shown in FIG. It is a flow chart for explaining operation of a measuring instrument. 10 ... Signal detection section, 12 ... input conversion section, 14 ... arithmetic processing section, 16 ... memory, 18 ... display section, 20 ... bus line, 22 ... signal transmission path, 24 ... transformation Vessel, 26 …… Transformer.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 塩野 繁男 茨城県日立市国分町１丁目１番１号 株式 会社日立製作所国分工場内 (56)参考文献 特開 昭60−205377（ＪＰ，Ａ) 特開 平２−190769（ＪＰ，Ａ) 実開 昭57−29864（ＪＰ，Ｕ) ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shigeo Shiono 1-1-1 Kokubun-cho, Hitachi-shi, Ibaraki Inside the Kokubun Plant of Hitachi, Ltd. (56) Reference JP-A-60-205377 (JP, A) Kaihei 2-190769 (JP, A) Actual opening Sho 57-29864 (JP, U)
Claims (1)
と、信号伝送路の電流を検出する電流検出手段と、前記
両検出手段の検出による瞬時値をそれぞれ順次デジタル
信号に変換する信号変換手段と、信号変換手段の各出力
信号から一定周期の有効電力Ｐ′と無効電力Ｑ′を算出
する第１電力算出手段と、信号検出時における電圧検出
手段と電流検出手段の各入出力間の位相差の総和を示す
位相誤差φに従った補正値cosφ,sinφを記憶する記憶
手段と、第１電力算出手段の各算出電力Ｐ′,Q′に対す
る補正値として記憶手段に記憶された補正値cosφ,sin
φを用い、真の有効電力ＰをＰ＝Ｐ′cosφ＋Ｑ′sin
φ、真の有効電力ＱをＱ＝Ｑ′cosφ−Ｐ′sinφにより
算出する第２電力算出手段とを有するデジタル電力計測
器。1. A voltage detecting means for detecting a voltage of a signal transmission path, a current detecting means for detecting a current of the signal transmission path, and a signal conversion for sequentially converting an instantaneous value detected by the both detecting means into a digital signal. Means, first power calculation means for calculating active power P'and reactive power Q'of a constant cycle from each output signal of the signal conversion means, and between each input / output of the voltage detection means and the current detection means at the time of signal detection. Storage means for storing the correction values cosφ, sinφ according to the phase error φ indicating the sum of the phase differences, and the correction value stored in the storage means as the correction value for each calculated power P ′, Q ′ of the first power calculation means. cosφ, sin
Using φ, the true active power P is P = P'cosφ + Q'sin
and a second effective power calculating means for calculating the true active power Q by Q = Q'cosφ-P'sinφ.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1246787A JPH07109424B2 (en) | 1989-09-22 | 1989-09-22 | Digital power meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1246787A JPH07109424B2 (en) | 1989-09-22 | 1989-09-22 | Digital power meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03108674A JPH03108674A (en) | 1991-05-08 |
| JPH07109424B2 true JPH07109424B2 (en) | 1995-11-22 |
Family
ID=17153668
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1246787A Expired - Fee Related JPH07109424B2 (en) | 1989-09-22 | 1989-09-22 | Digital power meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07109424B2 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003060540A1 (en) * | 2002-01-09 | 2003-07-24 | Mitsubishi Denki Kabushiki Kaisha | Electronic watthour meter, error adjusting method therefor and power computing circuit |
| JP2007132897A (en) * | 2005-11-14 | 2007-05-31 | Hioki Ee Corp | measuring device |
| JP6486205B2 (en) * | 2015-06-03 | 2019-03-20 | 大崎電気工業株式会社 | Phase adjustment system for power measurement |
| CN106443163B (en) * | 2016-09-22 | 2019-08-09 | 国网北京市电力公司 | Method and device for processing electric energy metering data |
| CN112912739B (en) | 2018-06-29 | 2024-06-11 | 布鲁萨电子公司 | Primary measuring device for measuring the currently acting power |
| US11519993B2 (en) * | 2018-07-30 | 2022-12-06 | Texas Instruments Incorporated | Current sensor configuration and calibration |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS598205Y2 (en) * | 1980-07-25 | 1984-03-13 | 株式会社東芝 | Electronic energy meter |
| JPS60205377A (en) * | 1984-03-30 | 1985-10-16 | Yokogawa Hokushin Electric Corp | Wattmeter |
-
1989
- 1989-09-22 JP JP1246787A patent/JPH07109424B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03108674A (en) | 1991-05-08 |
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