JP2000184658A - Diagnostic device for induction motor - Google Patents
Diagnostic device for induction motorInfo
- Publication number
- JP2000184658A JP2000184658A JP10352806A JP35280698A JP2000184658A JP 2000184658 A JP2000184658 A JP 2000184658A JP 10352806 A JP10352806 A JP 10352806A JP 35280698 A JP35280698 A JP 35280698A JP 2000184658 A JP2000184658 A JP 2000184658A
- Authority
- JP
- Japan
- Prior art keywords
- frequency
- power
- induction motor
- slip
- diagnostic device
- 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.)
- Pending
Links
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、回転子のバー切れ
等の異常を診断する誘導電動機の診断装置に関するもの
である。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diagnostic device for an induction motor for diagnosing abnormalities such as a broken bar of a rotor.
【０００２】[0002]
【従来の技術】特開平４−７９２２２号は、誘導電動機
の回転子巻線に流れる電流波形から、電流の復調波形を
得て「うなり周波数」を計数し、回転周波数計数回路に
よって計数した誘導電動機の固定子の回転周波数
（ｆ1 ）と、その固定子巻線に供給される電源周波数
（ｆ0 ）と、誘導電動機の極数（Ｐ）とから、誘導電動
機の固定子巻線電流に含まれるべき「うなり周波数」を
計算し、２つの「うなり周波数」を比較して、回転子導
体（バー）の破断を診断する誘導電動機の診断装置を提
案している。2. Description of the Related Art Japanese Unexamined Patent Publication No. 4-79222 discloses an induction motor in which a demodulation waveform of a current is obtained from a current waveform flowing through a rotor winding of an induction motor, a "beat frequency" is counted, and the beat frequency is counted by a rotation frequency counting circuit. Of the stator winding current of the induction motor from the stator rotation frequency (f 1 ), the power supply frequency (f 0 ) supplied to the stator winding, and the number of poles (P) of the induction motor. A diagnostic device for an induction motor that calculates a beat frequency to be beat, compares the two beat frequencies, and diagnoses a break in a rotor conductor (bar) is proposed.
【０００３】[0003]
【発明が解決しようとする課題】前述した従来の誘導電
動機の診断装置は、固定子の回転周波数（ｆ1 ）を測定
し、既知の電源周波数（ｆ0 ）と、極数（Ｐ）とから、
誘導電動機の固定子巻線電流に含まれるべきうなり周波
数を計算していた。The above-described conventional diagnostic device for an induction motor measures the rotation frequency (f 1 ) of the stator and determines the rotation frequency (f 1 ) of the stator from the known power supply frequency (f 0 ) and the number of poles (P). ,
The beat frequency to be included in the stator winding current of the induction motor was calculated.
【０００４】しかし、固定子の回転周波数（ｆ1 ）を測
定する場合に、電動機の出力軸に反射テープ等を貼っ
て、１回転−１パルスを非接触で検出するものが多い。
この場合に、電動機によっては、長時間にわたって停止
できないものもあり、作業時間が制限される等して、能
率が悪かった。However, in many cases, when measuring the rotation frequency (f 1 ) of the stator, a reflection tape or the like is attached to the output shaft of the electric motor to detect one rotation-1 pulse in a non-contact manner.
In this case, some motors cannot be stopped for a long time, so that the working time is limited and the efficiency is poor.
【０００５】また、電動機は、多数並べて配置されてい
る場合も多く、規格表示板が見えなかったり、古いもの
でデータが管理されていないときには、極数（Ｐ）を知
ることができない。[0005] Further, many motors are often arranged side by side, and the pole number (P) cannot be known when the standard display board is not visible or the data is not managed by an old motor.
【０００６】本発明の目的は、前述した課題を解決し、
回転周波数を測定できない場合や電源周波数や極数が未
知の場合であっても、異常診断を行うことを可能にする
誘導電動機の診断装置を提供することである。An object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide a diagnostic device for an induction motor that can perform abnormality diagnosis even when the rotation frequency cannot be measured or the power supply frequency and the number of poles are unknown.
【０００７】[0007]
【課題を解決するための手段】前記課題を解決するため
に、請求項１の発明は、誘導電動機の固定子に流れる負
荷電流を測定する負荷電流測定手段と、前記負荷電流に
基づいて、電流波形の周波数解析を行って、振幅変動を
求める周波数解析手段と、電源周波数を設定する電源周
波数設定手段と、前記振幅変動と前記電源周波数とに基
づいて、すべりを算出するすべり算出手段と、前記電源
周波数と前記すべりとに基づいて、側帯波位置を算出す
る側帯波位置算出手段と、前記側帯波位置のスペクトル
パワーを検出するスペクトルパワー検出手段と、前記ス
ペクトルパワーのピークと基準レベルと比較することに
より、前記誘導電動機の回転子の異常を判定する異常判
定手段と、を備えた誘導電動機の診断装置である。According to a first aspect of the present invention, a load current measuring means for measuring a load current flowing through a stator of an induction motor is provided. By performing frequency analysis of the waveform, frequency analysis means for obtaining amplitude fluctuation, power frequency setting means for setting the power frequency, slip calculation means for calculating the slip based on the amplitude fluctuation and the power frequency, Sideband position calculating means for calculating a sideband position based on the power supply frequency and the slip, spectrum power detecting means for detecting the spectral power of the sideband position, and comparing the peak of the spectral power with a reference level. Thus, there is provided an abnormality diagnosis device for an induction motor, comprising: abnormality determination means for determining abnormality of a rotor of the induction motor.
【０００８】請求項２の発明は、請求項１に記載の誘導
電動機の診断装置において、前記電源周波数設定手段
は、前記振幅変動のピークを電源周波数に設定するこ
と、を特徴とする誘導電動機の診断装置である。According to a second aspect of the present invention, in the induction motor diagnosis apparatus according to the first aspect, the power supply frequency setting means sets a peak of the amplitude fluctuation to a power supply frequency. It is a diagnostic device.
【０００９】[0009]
【発明の実施の形態】以下、図面等を参照して、本発明
の実施の形態について、さらに詳しくに説明する。図１
は、本発明による誘導電動機の診断装置の実施形態を示
すブロック図である。この実施形態の診断装置１０は、
電動機２０の負荷電流回路に電流クランププローブ等を
挿入して、その負荷電流を検出する電流計１１と、その
電流計１１で検出した電流波形をデジタル変換するＡ／
Ｄ変換器１２と、電動機２０の電源周波数を地域（我が
国の場合には、５０又は６０Ｈｚ）によって設定する電
源周波数設定部１３と、入出力信号のレベル調整や装置
全体を制御するマイクロコンピュータ（μＣＰＵ）１４
と、負荷電流波形を周波数分析等を行うＦＦＴプロセッ
サ１５と、診断に使用する脈動電流の大きさ等を表示す
る表示部１６と、警報を表示すると共に、警報信号を出
力する警報部１７等とから構成されている。Embodiments of the present invention will be described below in more detail with reference to the drawings. FIG.
1 is a block diagram showing an embodiment of a diagnostic device for an induction motor according to the present invention. The diagnostic device 10 according to this embodiment includes:
An ammeter 11 for inserting a current clamp probe or the like into a load current circuit of the motor 20 to detect the load current, and an A / A for digitally converting the current waveform detected by the ammeter 11
A D converter 12, a power frequency setting unit 13 for setting the power frequency of the electric motor 20 according to the region (50 or 60 Hz in Japan), and a microcomputer (μCPU) for adjusting the level of input / output signals and controlling the entire apparatus. ) 14
An FFT processor 15 for performing frequency analysis of a load current waveform, a display unit 16 for displaying the magnitude of a pulsating current used for diagnosis, an alarm unit 17 for displaying an alarm and outputting an alarm signal, and the like. It is composed of
【００１０】ここで、電動機２０の回転子２１は、軸２
２と、短絡環２３と、鉄心２４は、バー２５等を備えて
おり、電源から電力が供給され、出力軸に負荷が接続さ
れている。Here, the rotor 21 of the electric motor 20 is
2, the short-circuit ring 23, and the iron core 24 include a bar 25 and the like. Power is supplied from a power supply, and a load is connected to the output shaft.
【００１１】図２は、本実施形態に係る誘導電動機の診
断装置の動作を示す流れ図である。まず、μＣＰＵ１４
は、電源周波数設定部１３の設定値（電源周波数ｆ0 ）
等を読み取って、イニシャライズする（Ｓ１０１）。次
に、電流計１１からの固定子の負荷電流を入力し（Ｓ１
０２）、ＦＦＴプロセッサ１５によって、周波数解析を
行って、振幅変動周波数を求める（Ｓ１０３）。FIG. 2 is a flowchart showing the operation of the diagnostic device for an induction motor according to the present embodiment. First, the μCPU 14
Is the set value of the power supply frequency setting unit 13 (power supply frequency f 0 )
Is read and initialized (S101). Next, the load current of the stator from the ammeter 11 is input (S1).
02), frequency analysis is performed by the FFT processor 15 to obtain an amplitude fluctuation frequency (S103).
【００１２】ここで、電源周波数ｆ0 が設定されている
か否かを判断し（Ｓ１０４）、設定されている場合に
は、（振幅変動周波数）＝２ｓｆ0 （ｓはすべり）の式
から、すべりｓを算出する（Ｓ１０５）。そして、電源
周波数ｆ0 とすべりｓとから、ｆ0 −２ｓｆ0 ，ｆ0 ＋
２ｓｆ0 の式によって、図３に示すように、側帯波位置
を算出する（Ｓ１０６）。Here, it is determined whether or not the power supply frequency f 0 is set (S104). If the power supply frequency f 0 is set, the slip is obtained from the equation (amplitude fluctuation frequency) = 2sf 0 (s is slip). s is calculated (S105). Then, from the power supply frequency f 0 and the slip s, f 0 −2sf 0 , f 0 +
As shown in FIG. 3, the sideband position is calculated by the expression of 2sf 0 (S106).
【００１３】次いで、ＦＦＴプロセッサ１５の周波数解
析データから、側帯波位置（ｆ0 −２ｓｆ0 ，ｆ0 ＋２
ｓｆ0 ）のスペクトル値を読み込む（Ｓ１０７）。Next, from the frequency analysis data of the FFT processor 15, the sideband positions (f 0 -2sf 0 , f 0 +2
The spectrum value of (sf 0 ) is read (S107).
【００１４】最後に、μＣＰＵ１４は、対称位置にある
スペクトルのパワーの大きさから異常状態を評価する
（Ｓ１０８）。例えば、予め、蓄積された異常状態の等
級と、パワーとのテーブルを比較して、異常の等級を判
定する。異常であった場合には、異常である旨の表示と
警報を行い（Ｓ１０９）、正常の場合には、正常である
旨の表示を行って、処理を終了する（Ｓ１１０）。Finally, the μCPU 14 evaluates an abnormal state from the magnitude of the power of the spectrum at the symmetric position (S108). For example, a grade of the abnormality is determined by comparing a previously stored table of the magnitude of the abnormal state with the table of the power. If abnormal, a display indicating the abnormality and a warning are performed (S109). If normal, a display indicating the normal is performed, and the process is terminated (S110).
【００１５】一方、Ｓ１０４において、電源周波数ｆ0
が設定されていないと判断した場合には、Ｓ１０３のＦ
ＦＴプロセッサ１５の周波数解析データのピーク値を抽
出して、その値を電源周波数ｆ0 とみなして（Ｓ１１
０）、Ｓ１０５へ進む。つまり、電流信号を周波数分析
し、そのパワーを読み取ると、その最大値は、電源周波
数ｆ0 の位置で生じており、電源周波数ｆ0 が未知の場
合であっても、電源周波数ｆ0 が判明する。On the other hand, in S104, the power supply frequency f 0
If it is determined that is not set, F in S103
The peak value of the frequency analysis data of the FT processor 15 is extracted, and the value is regarded as the power supply frequency f 0 (S11).
0), and proceed to S105. In other words, a current signal frequency analysis and reading the power, the maximum value is caused by the position of the power frequency f 0, even when the power supply frequency f 0 is a case of unknown stand power frequency f 0 I do.
【００１６】以上のように、すべりｓは、電動機２０の
異常状態によって影響を受けるが、ここで対象とする初
期異状状態の下では、１〜数％程度である。また、側帯
波は、電源周波数ｆ0 を挟んで、±２ｓｆ0 の位置に、
すなわち対称状態に生じ、周波数分析の結果から、その
位置が特定できる。As described above, the slip s is affected by the abnormal state of the electric motor 20, but is about 1% to several% under the initial abnormal state of interest. Further, sideband, across the power frequency f 0, the position of ± 2SF 0,
That is, the position occurs in a symmetric state, and the position can be specified from the result of the frequency analysis.
【００１７】なお、正常状態では、側帯波のパワーが、
ゼロ又は微小であるが、２ｓｆ0 の値からその発生領域
が特定でき、その領域のパワーをもつスペクトルがなけ
れば、異常なしと判定することができる。In the normal state, the power of the sideband wave is
Although it is zero or very small, the generation region can be specified from the value of 2sf 0 , and if there is no spectrum having the power of the region, it can be determined that there is no abnormality.
【００１８】[0018]
【発明の効果】以上詳しく説明したように、本発明によ
れば、回転周波数を測定できない場合や電源周波数や極
数が未知の場合であっても、異常診断を行うことができ
る、という効果がある。As described above in detail, according to the present invention, even when the rotation frequency cannot be measured or the power supply frequency or the number of poles is unknown, an abnormality can be diagnosed. is there.
【図１】本発明による誘導電動機の診断装置の実施形態
を示すブロック図である。FIG. 1 is a block diagram showing an embodiment of a diagnostic device for an induction motor according to the present invention.
【図２】本実施形態に係る誘導電動機の診断装置の動作
を示す流れ図である。FIG. 2 is a flowchart showing an operation of the diagnostic device for the induction motor according to the embodiment.
【図３】本実施形態に係る誘導電動機の診断装置の側帯
波位置を説明する図である。FIG. 3 is a diagram illustrating a sideband position of the diagnostic device for the induction motor according to the embodiment;
１０ 診断装置 １１ 電流計 １２ Ａ／Ｄ変換器 １３ 電源周波数設定部 １４ マイクロコンピュータ（μＣＰＵ） １５ ＦＦＴプロセッサ １６ 表示部 １７ 警報部 ２０ 電動機 Reference Signs List 10 Diagnostic device 11 Ammeter 12 A / D converter 13 Power frequency setting unit 14 Microcomputer (μCPU) 15 FFT processor 16 Display unit 17 Alarm unit 20 Motor
───────────────────────────────────────────────────── フロントページの続き (72)発明者 佐藤 雄三 神奈川県横浜市緑区白山１−16−１ 株式 会社小野測器内 (72)発明者 伊倉 克人 神奈川県横浜市緑区白山１−16−１ 株式 会社小野測器内 (72)発明者 吉田 至 大阪府吹田市垂水町３−17−16 関西小野 測器販売株式会社内 Ｆターム(参考） 5H611 AA01 BB01 PP05 QQ05 RR00 UA02 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yuzo Sato 1-16-1 Hakusan, Midori-ku, Yokohama, Kanagawa Prefecture Ono Sokki Co., Ltd. (72) Inventor Katsuto Ikura 1-16, Hakusan, Midori-ku, Yokohama, Kanagawa -1 Ono Sokki Co., Ltd. (72) Inventor Itaru Yoshida 3-17-16 Tarumicho, Suita-shi, Osaka Kansai-Ono Sokki Sales Co., Ltd. F-term (reference) 5H611 AA01 BB01 PP05 QQ05 RR00 UA02
Claims (2)
測定する負荷電流測定手段と、 前記負荷電流に基づいて、電流波形の周波数解析を行っ
て、振幅変動を求める周波数解析手段と、 電源周波数を設定する電源周波数設定手段と、 前記振幅変動と前記電源周波数とに基づいて、すべりを
算出するすべり算出手段と、 前記電源周波数と前記すべりとに基づいて、側帯波位置
を算出する側帯波位置算出手段と、 前記側帯波位置のスペクトルパワーを検出するスペクト
ルパワー検出手段と、 前記スペクトルパワーのピークと基準レベルと比較する
ことにより、前記誘導電動機の回転子の異常を判定する
異常判定手段と、を備えた誘導電動機の診断装置。A load current measuring means for measuring a load current flowing through a stator of the induction motor; a frequency analyzing means for performing a frequency analysis of a current waveform based on the load current to obtain an amplitude variation; Power frequency setting means for setting; a slip calculating means for calculating a slip based on the amplitude fluctuation and the power frequency; and a sideband position for calculating a sideband position based on the power frequency and the slip. Calculating means, spectral power detecting means for detecting the spectral power at the sideband position, and abnormality determining means for comparing the peak of the spectral power with a reference level to determine the abnormality of the rotor of the induction motor, Induction motor diagnostic device provided with:
において、 前記電源周波数設定手段は、前記振幅変動のピークを電
源周波数に設定すること、を特徴とする誘導電動機の診
断装置。2. The diagnostic device for an induction motor according to claim 1, wherein the power supply frequency setting means sets a peak of the amplitude fluctuation to a power supply frequency.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10352806A JP2000184658A (en) | 1998-12-11 | 1998-12-11 | Diagnostic device for induction motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10352806A JP2000184658A (en) | 1998-12-11 | 1998-12-11 | Diagnostic device for induction motor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000184658A true JP2000184658A (en) | 2000-06-30 |
Family
ID=18426571
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10352806A Pending JP2000184658A (en) | 1998-12-11 | 1998-12-11 | Diagnostic device for induction motor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000184658A (en) |
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| JP2009050078A (en) * | 2007-08-20 | 2009-03-05 | Sumitomo Metal Ind Ltd | Device and method for determining abnormality of machine and equipment |
| JP2010016982A (en) * | 2008-07-03 | 2010-01-21 | Mitsubishi Electric Corp | Motor controller and method for detecting ground fault of motor |
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