JPH0320994B2 - - Google Patents
Info
- Publication number
- JPH0320994B2 JPH0320994B2 JP59065420A JP6542084A JPH0320994B2 JP H0320994 B2 JPH0320994 B2 JP H0320994B2 JP 59065420 A JP59065420 A JP 59065420A JP 6542084 A JP6542084 A JP 6542084A JP H0320994 B2 JPH0320994 B2 JP H0320994B2
- Authority
- JP
- Japan
- Prior art keywords
- power supply
- control
- variable frequency
- output
- change
- 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.)
- Expired - Lifetime
Links
- 230000007423 decrease Effects 0.000 claims description 4
- 230000005856 abnormality Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000010248 power generation Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
- H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
Description
この発明は可変周波数電源（以下VF電源と略
称する）で、電動機に電力を供給し、電動機でフ
アンポンプ等の回転体を駆動する可変周波数電源
の運転装置に関する。
The present invention relates to an operating device for a variable frequency power source (hereinafter abbreviated as VF power source) that supplies power to an electric motor and drives a rotating body such as a fan pump with the electric motor.
従来この種の装置として第１図に示すものがあ
つた。図に於て、１は商用電源、２ＢはVF電源、
３は電動機、４は回転体、５Ａは制御装置、６は
制御信号、７Ａは制御装置５Ａの制御出力信号、
８は電動機３と回転体４を機械的に結合するため
の連結器、９は開閉器である。
また、第２図は第１図の説明用タイムチヤート
図で、t1は制御出力信号７Ａに断線（接続端子の
はずれ、ゆるみ等を含む）が発生した時のタイミ
ングスタート点、t2は断線発生t1後にシステム出
力が安定する時のタイミングストツプ点、Ｆは
VF電源２Ｂの出力周波数、ｎは電動機３の回転
数、Ｑは回転体４の出力風量を示す。
次に第１図の動作について以下に説明する。
商用電源１より開閉器９を介してVF電源２Ｂ
に電源電圧が印加されている場合、VF電源２Ｂ
の出力周波数Ｆと電動機３の回転数ｎとの間には
(1)式の関係がある。
ｎ＝120×Ｆ／Ｐ ……(1)
但し、Ｐ：電動機３の極数
従つて、回転体４をフアンとして説明すれば、
フアン４の出力風量Ｑは回転数ｎにほぼ比例して
変化する。VF電源２Ｂを発電プラントのボイラ
に適用しているとすれば、電力系統からの要請や
燃料の供給状況の変化に対して出力風量Ｑの発生
要求に変化があり、この変化信号が制御信号６と
して与えられる。この制御信号６は制御装置５Ａ
で制御に適する制御出力信号７Ａ（例えば、４〜
20ｍＡの電流信号）に変換されてVF電源２Ｂに
伝達され、出力周波数Ｆを要求の値に追従させ(1)
式に示した電動機３数ｎの変化に伴うフアン４の
出力風量Ｑを変化させる。
従来のVF電源２Ｂは以上のように構成されて
いるので、第２図のようにt1時点で制御装置５Ａ
とVF電源２Ｂとの間に信号線の断線等が発生す
ると制御信号６は正常であるにもかかわらず、制
御出力信号７Ａが零に変化してVF電源２Ｂの出
力周波数Ｆを第２図のように変化させることにな
る。
従つて、出力周波数Ｆが変化すると(1)式の如く
電動機３の回転数ｎ、及び、フアン４の出力風量
Ｑが変化する。すなわち回転体４の出力が変化し
てはならない時に出力が大巾に変化してプラント
停止等の事故に波及するという欠点があつた。
A conventional device of this type is shown in FIG. In the figure, 1 is commercial power supply, 2B is VF power supply,
3 is an electric motor, 4 is a rotating body, 5A is a control device, 6 is a control signal, 7A is a control output signal of the control device 5A,
8 is a coupler for mechanically coupling the electric motor 3 and the rotating body 4, and 9 is a switch. In addition, Fig. 2 is a time chart for explaining Fig. 1, where t 1 is the timing start point when a disconnection (including disconnection or loosening of the connection terminal, etc.) occurs in the control output signal 7A, and t 2 is the timing start point when the disconnection occurs in the control output signal 7A. The timing stop point, F, when the system output stabilizes after occurrence t1 is
The output frequency of the VF power supply 2B, n indicates the rotation speed of the electric motor 3, and Q indicates the output air volume of the rotating body 4. Next, the operation shown in FIG. 1 will be explained below. VF power supply 2B from commercial power supply 1 via switch 9
When the power supply voltage is applied to VF power supply 2B
Between the output frequency F and the rotation speed n of the electric motor 3 is
There is a relationship expressed by equation (1). n=120×F/P...(1) However, P: Number of poles of electric motor 3 Therefore, if the rotating body 4 is explained as a fan,
The output air volume Q of the fan 4 changes approximately in proportion to the rotation speed n. If the VF power supply 2B is applied to the boiler of a power generation plant, there will be a change in the generation request for the output air volume Q in response to a request from the power system or a change in the fuel supply situation, and this change signal will be the control signal 6. given as. This control signal 6 is the control device 5A.
Control output signal 7A suitable for control (for example, 4~
20mA current signal) and transmitted to the VF power supply 2B, making the output frequency F follow the required value (1)
The output air volume Q of the fan 4 is changed as the number n of the electric motors 3 shown in the equation changes. Since the conventional VF power supply 2B is configured as described above, the control device 5A is activated at time t1 as shown in FIG.
If a break in the signal line or the like occurs between the VF power supply 2B and the control signal 6, the control output signal 7A changes to zero, causing the output frequency F of the VF power supply 2B to change as shown in Fig. 2. It will be changed like this. Therefore, when the output frequency F changes, the rotation speed n of the electric motor 3 and the output air volume Q of the fan 4 change as shown in equation (1). That is, there is a drawback that the output of the rotating body 4 changes drastically when it should not change, which may lead to accidents such as plant shutdown.
この発明は上記のような従来のものの欠点を除
去するためになされたもので、制御信号６を制御
装置内で積分し、その出力信号をVF電源に伝達
し、前記積分された入力信号の変化率を検出する
変化率検出器を前記VF電源内にもうけ、該変化
率検出器が前記積分された制御出力信号が所定の
変化率範囲を外れたことを検知したときに、電動
機３への電力供給電源をVF電源３より商用電源
１に切替えることによりVF電源システムを安全
に継続して運転できる可変周波数電源の運転装置
を提供することを目的としている。
This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and it integrates the control signal 6 within the control device, transmits the output signal to the VF power supply, and changes the integrated input signal. A rate of change detector for detecting the rate of change is provided in the VF power supply, and when the rate of change detector detects that the integrated control output signal is out of a predetermined rate of change range, power to the motor 3 is The purpose of the present invention is to provide a variable frequency power supply operating device that can safely and continuously operate a VF power supply system by switching the power supply from the VF power supply 3 to the commercial power supply 1.
以下、この発明の一実施例を図について説明す
る。図中、第１図と同一の部分は同一の符号をも
つて図示した第３図に於て、２はVF電源２Ｂと
変化率検出器２Ａにより構成されるVF電源シス
テム、５Ｂは制御装置、７Ｂは前記制御装置５Ｂ
の出力信号、１０及び１１は開閉である。
また、第４図は第３図の説明用タイムチヤート
図である。図に於て、t3は開閉器９及び１０の開
放完了時点、t4は開閉器１１の閉成完了時点、t5
は電動機３が商用電源１の周波数に相当する回転
数に達した時点、t6は回転体４（フアン）の出力
風量Ｑが定常値に安定する血点を示す。
第５図は変化率異常検出器の構成図を示し、第
６図はその動作を説明する説明図である。
図に於て、IINは入力信号、G1、G2はセレクタ
スイツチ、PGRはパルスジエネレータ、HLD1、
HLD2はホールド回路、DTRは差電圧検出器、
COMは大きさ判定器である。
次に第３図の動作を以下に説明する。
まず開閉器９及び１０がON、開閉器１１が
OFFとすると、第１図と同様に商用電源１でVF
電源２Ｂに電源電圧が引火され、その出力で電動
機３が駆動され、フアン４が回転される。フアン
４の出力風量Ｑに対する変化指令は制御信号６と
して制御装置５Ｂに与えられ、その制御装置５Ｂ
の積分回路５Ｃで積分された制御出力信号７Ｂを
VF電源システム２に与える。次にVF電源システ
ム２を構成している変化率検出器２Ａで前記制御
出力信号７Ｂの変化率を検出し、所定の変化率範
囲であればその制御出力信号７Ｂに相当する周波
数にVF電源２Ｂの出力周波数Ｆを追従させ、所
定の変化率範囲を外れたことを検知するときは開
閉器９，１０をOFFし、ひきつづき開閉器１１
をONにさせる。上記変化率検出器２Ａの動作は
第５図からも理解できるようにパルスジエネレタ
PGRは一定間隔でパルスを発生しており、セレ
クタ・スイツチG1、G2はこのパルスに交互に応
答して入力信号IINの瞬時値をそれぞれホールド
回路HLD1、HLD2へ送る。
入力信号IINが第６図のように変化するとすれ
ば、ホールド回路HLD1、HLD2は交互のパルス
時点における入力信号IINの瞬時値を図のように
出力する。ホールド回路HLD1、HLD2の出力差
は差電圧検出器DTRで検出し、その差電圧が一
定値以上となつたとき（t2＋α時点）に入力信号
IINに異常な変化があつたとして出力信号を送出
する。なおαはパルスジエネレータPGRのパル
ス間隔に相当している。
従つて第４図に示す如くt1時点で制御装置５Ｂ
とVF電源システム２との間に信号線の断線等が
生じても、変化率検出器２Ａが直ちに異常を検出
し、開閉器９，１０を開放（t3時点）、開閉器１
１を閉成（t4時点）する。電動機３の回転数ｎ
は、開閉器９，１０の開放で一時無電圧状態とな
つて回転数は多少減少するが、開閉器１１の引続
いての閉成動作によつて回転数は再び上昇しt5時
点で商用電源１の周波数に相当する回転数に達す
る。また、回転体４がフアンの場合で説明する
と、出力風量Ｑの制御には回転数ｎによる制御の
他に機会式の入口ベーン（又はタンパ）制御（図
示せず）がある。回転数ｎによる出力風量Ｑ制御
の時は出力損失を少くするために入口ベーンはほ
ぼ全開に近い点で運転されている。前記のように
回転数ｎが商用電源１の周波数に相当する値まで
上昇すれば、出力風量Ｑは入力ベーンを回転数ｎ
による風量制御の時のままにしておくと変化が大
きくあらられることとなる。従つて変化率検出器
２Ａの動作、開閉器９及び１０の開放、開閉器１
１の閉成等を条件として前記入口ベーンを出力風
量Ｑの減少方向にしぼり込むように操作する。
従つて、第４図の出力風量Ｑは、閉会器９，１
０の開放で１度減少し、開閉器１１の閉成で上昇
に転ずる。入口ベーンの応答は回転数ｎ増加によ
る出力風量Ｑの増加より通常の場合おくれてお
り、従つて出力風量Ｑは回転数ｎの上昇中は入口
ベーンの減少作用により若干ゆるやかとなつて上
昇し、回転数ｎが商用電源１による回転数に達し
た後（時点t5以後）では出力風量Ｑは入口ベーン
の作用によつて減少してゆき時点t6で元の値にも
どることになる。
このように出力風量Ｑは変化するが、変化巾は
システムの許容範囲内におさめられ、制御出力信
号７Ｂに異常が発生しても安全に運転を継続でき
る。
以上は発電プラント、フアンを例に説明した
が、他のプラント等の用途、例えばポンプ等の他
の回転体に適用してよいことは明らかである。
また断線を例に説明したが、短絡等の他の異常
でもよく、信号伝送線の異常ではなく制御装置５
Ｂの異常で制御出力信号７Ｂが異常となつた場合
でもよい。
An embodiment of the present invention will be described below with reference to the drawings. In FIG. 3, the same parts as in FIG. 1 are designated by the same reference numerals. In FIG. 7B is the control device 5B
The output signals 10 and 11 are open/close. 4 is an explanatory time chart of FIG. 3. In the figure, t 3 is the time when switches 9 and 10 are completed opening, t 4 is the time when switch 11 is completely closed, and t 5
t6 indicates the point at which the electric motor 3 reaches a rotational speed corresponding to the frequency of the commercial power source 1, and t6 indicates the point at which the output air volume Q of the rotating body 4 (fan) stabilizes at a steady value. FIG. 5 shows a configuration diagram of the rate of change abnormality detector, and FIG. 6 is an explanatory diagram illustrating its operation. In the figure, I IN is the input signal, G 1 and G 2 are the selector switches, PGR is the pulse generator, HLD 1 ,
HLD 2 is a hold circuit, DTR is a differential voltage detector,
COM is a size judger. Next, the operation shown in FIG. 3 will be explained below. First, switches 9 and 10 are ON, and switch 11 is ON.
When set to OFF, VF is turned off at commercial power supply 1 as shown in Figure 1.
A power supply voltage is ignited in the power supply 2B, and the electric motor 3 is driven by its output, and the fan 4 is rotated. A change command for the output air volume Q of the fan 4 is given to the control device 5B as a control signal 6, and the control device 5B
The control output signal 7B integrated by the integrating circuit 5C of
Supply to VF power system 2. Next, the change rate detector 2A constituting the VF power supply system 2 detects the change rate of the control output signal 7B, and if the change rate is within a predetermined change rate range, the VF power supply 2B changes the frequency corresponding to the control output signal 7B. When detecting that the output frequency F is out of the predetermined rate of change range, switches 9 and 10 are turned OFF, and switch 11 is then turned OFF.
Turn on. As can be understood from FIG. 5, the operation of the rate of change detector 2A is based on the pulse generator.
The PGR generates pulses at regular intervals, and the selector switches G 1 and G 2 alternately respond to these pulses and send the instantaneous values of the input signal I IN to the hold circuits HLD 1 and HLD 2 , respectively. If the input signal I IN changes as shown in FIG. 6, the hold circuits HLD 1 and HLD 2 output the instantaneous values of the input signal I IN at alternate pulse times as shown. The output difference between the hold circuits HLD 1 and HLD 2 is detected by the differential voltage detector DTR, and when the differential voltage exceeds a certain value (at time t 2 + α), the input signal is detected.
I Sends an output signal when there is an abnormal change in IN . Note that α corresponds to the pulse interval of the pulse generator PGR. Therefore, as shown in FIG. 4, at time t1 , the control device 5B
Even if a break in the signal line or the like occurs between the VF power supply system 2 and the VF power supply system 2, the rate of change detector 2A immediately detects the abnormality, opens switches 9 and 10 (at time t 3 ), and closes switch 1.
1 is closed (at time t 4 ). Rotation speed n of electric motor 3
When the switches 9 and 10 are opened, there is a temporary no-voltage state and the rotational speed decreases a little, but the rotational speed increases again with the subsequent closing of the switch 11, and at time t5 , the The rotational speed corresponds to the frequency of the power source 1. Further, in the case where the rotary body 4 is a fan, the output air volume Q is controlled by an opportunistic inlet vane (or tamper) control (not shown) in addition to control based on the rotation speed n. When the output air volume Q is controlled by the rotational speed n, the inlet vane is operated at a point close to fully open in order to reduce output loss. As mentioned above, if the rotation speed n increases to a value corresponding to the frequency of the commercial power source 1, the output air volume Q will increase the rotation speed n of the input vane.
If the air volume is left as it was when controlling the air volume, there will be a large change. Therefore, the operation of the rate of change detector 2A, the opening of switches 9 and 10, and the opening of switch 1
1 is closed, etc., the inlet vane is operated so as to be compressed in the direction of decreasing the output air volume Q. Therefore, the output air volume Q in FIG.
When the switch 11 is closed, it decreases by 1 degree, and when the switch 11 is closed, it starts to rise. The response of the inlet vane normally lags behind the increase in the output air volume Q due to an increase in the rotational speed n, and therefore, while the rotational speed n is increasing, the output airflow Q rises somewhat gradually due to the decreasing effect of the inlet vane. After the rotational speed n reaches the rotational speed of the commercial power source 1 (after time t5 ), the output air volume Q decreases due to the action of the inlet vane, and returns to its original value at time t6 . Although the output air volume Q changes in this way, the range of change is kept within the permissible range of the system, and even if an abnormality occurs in the control output signal 7B, operation can be continued safely. Although the above description has been made using a power generation plant and a fan as an example, it is clear that the present invention may be applied to other plants, for example, other rotating bodies such as pumps. Furthermore, although the explanation has been given using a disconnection as an example, other abnormalities such as short circuits may also be considered, and the control device 5 may not be an abnormality in the signal transmission line.
It may also be possible that the control output signal 7B becomes abnormal due to an abnormality in signal B.
以上のように、この発明によれば制御装置の中
で制御信号を積分してから制御出力信号として
VF電源システム２に送出し、前記積分された制
御出力信号が所定の変化率範囲であるか否かを変
化率検出器で監視し、前記変化率検出器が所定の
変化率範囲を外れたことを検知したとき、電動機
への印加電源をVF電源から商用電源に切替える
ように回路構成したので、設備を連続して、安全
に運転できる効果がある。
As described above, according to the present invention, the control signal is integrated in the control device and then output as the control output signal.
The integrated control output signal is sent to the VF power supply system 2, and a change rate detector monitors whether or not the integrated control output signal is within a predetermined change rate range. The circuit is configured to switch the power applied to the motor from VF power to commercial power when this is detected, making it possible to operate the equipment continuously and safely.
第１図は従来の可変周波数電源を用いた電動機
速度制御系の系統図、第２図は第１図の説明用タ
イムチヤート図、第３図はこの発明の可変周波数
電源を用いた電動機速度制御系の系統図、第４図
は第３図の説明用タイムチヤート図、第５図は変
化率検出器の構成図、第６図は第５図の説明図で
ある。
１……商用電源、２……VF電源システム、２
Ａ……変化率検出器、２Ｂ……可変周波数電源
（VF電源）、３……電動機、４……回転体、５Ａ，
５Ｂ……制御装置、５Ｃ……積分回路、６……制
御信号、７Ｂ……制御出力信号、８……連結器、
９，１０，１１……開閉器。
Fig. 1 is a system diagram of a motor speed control system using a conventional variable frequency power supply, Fig. 2 is a time chart for explaining Fig. 1, and Fig. 3 is a motor speed control system using a variable frequency power supply according to the present invention. FIG. 4 is an explanatory time chart of FIG. 3, FIG. 5 is a configuration diagram of the rate of change detector, and FIG. 6 is an explanatory diagram of FIG. 5. 1...Commercial power supply, 2...VF power supply system, 2
A... Rate of change detector, 2B... Variable frequency power supply (VF power supply), 3... Electric motor, 4... Rotating body, 5A,
5B...Control device, 5C...Integrator circuit, 6...Control signal, 7B...Control output signal, 8...Coupler,
9, 10, 11... Switch.
Claims (1)
電動機に結合された回転体の回転数を制御するた
め前記可変周波数電源に与える制御信号を発生す
る制御装置とを有する可変周波数電源の運転装置
において、前記回転体の出力増減を指示する制御
信号を前記制御装置内に設けた積分回路で積分
し、前記積分された出力信号を制御出力信号とし
て可変周波数電源システム内の変化率検出器に伝
達し、前記積分された制御出力信号が所定の変化
率範囲を外れたことを変化率検出器が検知したと
き上記電動機の供給電源を可変周波数電源から商
用電源に切替えるようにしたことを特徴とする可
変周波数電源の運転装置。1. A variable frequency power supply operating device comprising an electric motor connected to a variable frequency power supply and a control device that generates a control signal to be applied to the variable frequency power supply to control the rotation speed of a rotating body coupled to the motor, integrating a control signal instructing an increase or decrease in the output of the rotating body by an integrating circuit provided in the control device, transmitting the integrated output signal as a control output signal to a rate of change detector in the variable frequency power supply system; Variable frequency, characterized in that when a rate of change detector detects that the integrated control output signal is out of a predetermined rate of change range, the power supply to the motor is switched from the variable frequency power supply to the commercial power supply. Power supply driving device.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59065420A JPS60210193A (en) | 1984-04-02 | 1984-04-02 | Operation system of variable frequency power source |
| KR1019850000354A KR890005315B1 (en) | 1984-04-02 | 1985-01-22 | Variable freguency power unit controlling system |
| US06/698,850 US4691156A (en) | 1984-04-02 | 1985-02-06 | Variable frequency power unit controlling system |
| CA000474032A CA1235734A (en) | 1984-04-02 | 1985-02-11 | Variable frequency power unit controlling system |
| EP85101510A EP0160787B1 (en) | 1984-04-02 | 1985-02-13 | Variable frequency power unit controlling system |
| DE8585101510T DE3562963D1 (en) | 1984-04-02 | 1985-02-13 | Variable frequency power unit controlling system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59065420A JPS60210193A (en) | 1984-04-02 | 1984-04-02 | Operation system of variable frequency power source |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60210193A JPS60210193A (en) | 1985-10-22 |
| JPH0320994B2 true JPH0320994B2 (en) | 1991-03-20 |
Family
ID=13286544
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59065420A Granted JPS60210193A (en) | 1984-04-02 | 1984-04-02 | Operation system of variable frequency power source |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60210193A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022064977A1 (en) | 2020-09-24 | 2022-03-31 | 株式会社クリエイティブテクノロジー | Dust collector and dust collection method |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69714606T9 (en) * | 1996-12-31 | 2004-09-09 | Rosemount Inc., Eden Prairie | DEVICE FOR CHECKING A CONTROL SIGNAL COMING FROM A PLANT IN A PROCESS CONTROL |
-
1984
- 1984-04-02 JP JP59065420A patent/JPS60210193A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022064977A1 (en) | 2020-09-24 | 2022-03-31 | 株式会社クリエイティブテクノロジー | Dust collector and dust collection method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60210193A (en) | 1985-10-22 |
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