JPH0282000A - Operational condition detecting method for turbo molecular pump - Google Patents
Operational condition detecting method for turbo molecular pumpInfo
- Publication number
- JPH0282000A JPH0282000A JP23526788A JP23526788A JPH0282000A JP H0282000 A JPH0282000 A JP H0282000A JP 23526788 A JP23526788 A JP 23526788A JP 23526788 A JP23526788 A JP 23526788A JP H0282000 A JPH0282000 A JP H0282000A
- Authority
- JP
- Japan
- Prior art keywords
- motor
- pressure
- detecting
- control
- flow rate
- 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
- 238000000034 method Methods 0.000 title claims abstract description 25
- 230000006698 induction Effects 0.000 claims description 5
- 230000006835 compression Effects 0.000 abstract description 3
- 238000007906 compression Methods 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000001514 detection method Methods 0.000 description 3
- 238000005086 pumping Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 1
Landscapes
- Control Of Positive-Displacement Air Blowers (AREA)
- Non-Positive Displacement Air Blowers (AREA)
- Control Of Positive-Displacement Pumps (AREA)
Abstract
Description
【発明の詳細な説明】
この発明はターボ分子ポンプの運転状態検出方法に関す
るものであって、特に運転時の圧力や流量を検出するた
めの方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting the operating state of a turbomolecular pump, and more particularly to a method for detecting pressure and flow rate during operation.
従来、ターボ分子ポンプにおいては、ポンプ作動中の圧
力を検出するための真空計が使用されている。このよう
な真空計の使用は、コスト、スペース等の関係から好ま
しいものではなく、そのためモータ駆動状態から圧力等
を把握する方策を採用することが考えられる。Conventionally, turbomolecular pumps use vacuum gauges to detect pressure during pump operation. The use of such a vacuum gauge is not preferable in terms of cost, space, etc. Therefore, it is conceivable to adopt a method of ascertaining the pressure etc. from the motor driving state.
しかしながら従来のインバータ方式の誘導モータを使用
したターボ分子ポンプの運転は、Ｖ／Ｆを固定し、定常
運転時の■、Ｆ（！に固定して行われている。したがっ
て回転翼は、モータとインバータの特性によって決まる
トルク曲線上の点で、負荷トルクと釣り合った回転数で
回転することになり、そのため負荷が変化するとそれに
伴って回転数も変化しく第３図参照ｄ−＋ｅ）、ターボ
分子ポンプの圧縮比、排気速度が変化するために正確な
圧力検出を行うことは不可能である。また直流モータを
使用する場合にも、モータへの印加電圧が固定されてい
るため、上記同様な理由から正確な圧力検出を行うこと
が不可能である。However, conventional turbomolecular pumps using inverter type induction motors are operated with V/F fixed at ■ and F(! during steady operation. Therefore, the rotor blades are connected to the motor. At a point on the torque curve determined by the characteristics of the inverter, it rotates at a rotation speed that is balanced with the load torque. Therefore, when the load changes, the rotation speed also changes accordingly. Accurate pressure detection is impossible because the pump compression ratio and pumping speed change. Further, even when a DC motor is used, since the voltage applied to the motor is fixed, it is impossible to perform accurate pressure detection for the same reason as above.
この発明は上記に鑑みなされたものであって、その目的
は、モータの制御状態に基づいて圧力や流量を正確に検
出でき、そのため従来のような真空計の使用を不要にし
得るターボ分子ポンプの運転状態検出方法を提供するこ
とにある。This invention was made in view of the above, and its purpose is to provide a turbo-molecular pump that can accurately detect pressure and flow rate based on the control status of the motor, thereby eliminating the need for the use of a conventional vacuum gauge. An object of the present invention is to provide a method for detecting operating conditions.
すなわちこの発明のターボ分子ポンプの運転状態検出方
法では、モータにて回転翼を回転駆動すると共に、回転
翼の負荷状態を検出し、この負荷状態をフィードバック
して回転翼を一定回転数で回転させるべくターボ分子ポ
ンプを構成し、さらに上記負荷状態に見合うモータ制御
特性値を把握し、これに基づいて圧力又は流量を検出す
るようにしている。That is, in the operating state detection method of a turbomolecular pump of the present invention, a rotor is driven to rotate by a motor, a load state of the rotor is detected, and this load state is fed back to rotate the rotor at a constant rotation speed. The turbo-molecular pump is configured to suit the above-mentioned load condition, and the motor control characteristic value corresponding to the load condition is determined, and the pressure or flow rate is detected based on this.
次にこの発明のターボ分子ポンプの運転状態検出方法の
具体的な実施例について、図面を参照しつつ詳細に説明
する。Next, a specific embodiment of the method for detecting the operating state of a turbomolecular pump according to the present invention will be described in detail with reference to the drawings.
まずこの方法は、ターボ分子ポンプにおける回転翼の負
荷の状態をモニターし、負帰還をかけて回転翼を常に一
定回転数で回転させ、ターボ分子ポンプの圧縮比、排気
速度を一定に保持するような制御を行うことを前提とす
る。そして回転翼の負荷はガスの量であることから、回
転翼を駆動するモータの制御パラメータを使用して流量
の検出を行うのである。また圧力Ｐと排気速度Ｓと流量
Ｑとの関係は、Ｐ＝Ｑ／Ｓとなることから、Ｓが一定の
条件下において圧力Ｐと流量Ｑとを同時に検出し得るこ
とになる。First, this method monitors the load condition of the rotor blades in the turbomolecular pump, applies negative feedback, and always rotates the rotor blades at a constant rotation speed to maintain the compression ratio and pumping speed of the turbomolecular pump constant. It is assumed that appropriate control will be performed. Since the load on the rotor blade is the amount of gas, the flow rate is detected using the control parameters of the motor that drives the rotor blade. Furthermore, since the relationship between pressure P, pumping speed S, and flow rate Q is P=Q/S, pressure P and flow rate Q can be detected simultaneously under a condition where S is constant.
次に回転翼をインバータ方式の誘導モータにて駆動し、
インバータが、回転数、負荷電流のいずれか一方、又は
両者の信号に基づいて回転翼の回転数を設定値に維持す
るような制御を行う場合の圧力等の検出方法について説
明する。まずこのような場合において、Ｖ／Ｆ （ただ
し、Ｆは駆動周波数、■はモータ印加電圧）を一定にし
たまま駆動周波数と電圧とを変化させるような制御方式
、すなわち滑り周波数を変化させて負荷に見合うトルク
を発生させ、これにより設定回転数を維持するような制
御方式を採用するときには、回転数設定周波数と駆動周
波数との差を把握し、これを圧力又は流量に変換すれば
よい（第１図及び第４図参照）、また上記に代えて負荷
電流とモータ印加電圧との位相差を圧力又は流量に変換
することも可能である（第１図及び第５図参照）。なお
第１図において、ａは定常運転時の回転数、ｂは負荷変
動時の制御前における予想動作点、Ｃは制御後の動作点
をそれぞれ示している。Next, the rotor blades are driven by an inverter-type induction motor,
A method of detecting pressure and the like when the inverter performs control to maintain the rotational speed of the rotor at a set value based on a signal from either the rotational speed or the load current, or both will be described. First, in such a case, a control method that changes the driving frequency and voltage while keeping V/F (F is the driving frequency and When adopting a control method that maintains the set rotation speed by generating torque corresponding to 1 and 4), and instead of the above, it is also possible to convert the phase difference between the load current and the voltage applied to the motor into pressure or flow rate (see FIGS. 1 and 5). In FIG. 1, a indicates the rotational speed during steady operation, b indicates the expected operating point before control during load fluctuations, and C indicates the operating point after control.
一方、インバータが駆動周波数Ｆを一定にしたままでモ
ータ印加電圧を変化させ、これにより負荷に見合うトル
クを発生させ設定回転数を維持するような制御方式を採
用する場合には、モータ印加電圧を圧力又は流量に変換
する（第２図及び第５図参照）。またこの場合には、イ
ンバータの出力制御電圧（交流出力を作る前の直流制御
電圧）を圧力又は流量に変換したり、あるいはインバー
タの出力制御回路を流れる電流を圧力又は流量に変換す
ることもできる（第２図及び第６図参照）。On the other hand, when adopting a control method in which the inverter changes the voltage applied to the motor while keeping the drive frequency F constant, thereby generating torque commensurate with the load and maintaining the set rotation speed, the voltage applied to the motor can be changed. Convert to pressure or flow rate (see Figures 2 and 5). In this case, it is also possible to convert the inverter's output control voltage (DC control voltage before creating AC output) into pressure or flow rate, or convert the current flowing through the inverter's output control circuit into pressure or flow rate. (See Figures 2 and 6).
しかも上記インバータの出力制御電圧がＰＬＬ（Ｐｈａ
ｓｅ Ｌｏｃｋｅｄ Ｌｏｏｐ ）によって得られるも
のである場合には、回転精度を高めることが可能となり
、この結果、圧力や流量の微少な変動をも検出し得るこ
とになる（第２図及び第７図参照）、なお第２図におい
て、ｆは定常運転時の動作点、ｇは負荷変動時の動作点
、ｈは設定回転数をそれぞれ示している。Moreover, the output control voltage of the inverter is PLL (Pha
If the rotational accuracy is obtained by a locking loop (see Locked Loop), it becomes possible to increase the rotational accuracy, and as a result, it becomes possible to detect even minute fluctuations in pressure and flow rate (see Figures 2 and 7). ), and in FIG. 2, f indicates the operating point during steady operation, g indicates the operating point during load fluctuation, and h indicates the set rotation speed.
ところで回転翼を直流モータで駆動し、回転翼の回転数
を検出して設定回転数に維持する場合、負荷変動による
回転数の変化に応じてモータ印加電圧を変化させ、負荷
に見合うトルクを発生させるような制御が行われる訳で
あるが、このような制御方式が採用される場合には、モ
ータ印加電圧制御回路の制御電圧を圧力又は流量に変換
すればよいし、あるいはモータ印加電圧制御回路を流れ
る電流を圧力又は流量に変換してもよい（第８図及び第
６図参照）。またさらにモータに印加される電圧を圧力
や流量に変換したり、モータに発生するトルクに応じて
変化するモータへの通電電流を圧力や流量に変換するこ
とも可能である（第８図、第５図及び第９図参照）、な
お第８図において、ｉは定常時の動作点、ｊは負荷変動
時の動作点、ｋは定常時の回転数になるよう制御したと
きの動作点、Ｖ、 、Ｖ、は制御前後のモータ印加電圧
をそれぞれ示している。By the way, when the rotor blades are driven by a DC motor and the rotation speed of the rotor blades is detected and maintained at the set rotation speed, the voltage applied to the motor is changed in response to changes in the rotation speed due to load fluctuations, and a torque corresponding to the load is generated. However, if such a control method is adopted, the control voltage of the motor applied voltage control circuit may be converted into pressure or flow rate, or the motor applied voltage control circuit may be The current flowing through the tube may be converted into pressure or flow rate (see FIGS. 8 and 6). Furthermore, it is also possible to convert the voltage applied to the motor into pressure or flow rate, or convert the current applied to the motor, which changes depending on the torque generated in the motor, into pressure or flow rate (Fig. 8, 5 and 9), and in Fig. 8, i is the operating point at steady state, j is the operating point at load fluctuation, k is the operating point when the rotation speed is controlled to be at steady state, and V , , and V indicate the motor applied voltages before and after control, respectively.
第１０図には、第５図における圧力又は流量変換回路の
実施例を、第１１図には、第６図及び第７図の圧力又は
流量変換回路の実施例をそれぞれ示している。また第１
２図及び第１３図には、周波数Ｆを検出する場合におけ
る第５図〜第６図の圧力又は流量変換回路の実施例を示
す。FIG. 10 shows an embodiment of the pressure or flow rate conversion circuit in FIG. 5, and FIG. 11 shows an embodiment of the pressure or flow rate conversion circuit in FIGS. 6 and 7. Also the first
2 and 13 show examples of the pressure or flow rate conversion circuits of FIGS. 5 and 6 in the case of detecting the frequency F.
上記したターボ分子ポンプの運転状態検出方法において
は、次の■〜■の利点が生ずる。すなわち、
■真空計を別に設け、これにより測定する必要が生じな
い。The above-described method for detecting the operating state of a turbomolecular pump provides the following advantages (1) to (4). That is, (1) there is no need to provide a separate vacuum gauge for measurement;
■真空チェンバの圧力設定が自由に行える。■The vacuum chamber pressure can be set freely.
■ガス流量の設定を他のコントローラを用いることなく
行える。■Gas flow rate can be set without using any other controller.
■上記圧力又は流量を、排気システム、ガス供給装置、
その他の真空装置のシーケンス制御のための信号として
使用し得る。■The above pressure or flow rate is determined by the exhaust system, gas supply device,
It can be used as a signal for sequence control of other vacuum devices.
ということである。That's what it means.
この発明のターボ分子ポンプの運転状態検出方法は上記
のように構成されたものであって、そのためこの発明の
ターボ分子ポンプの運転状態検出方法では、モータの制
御状態に基づいて圧力や流量を正確に検出でき、そのた
め従来のような真空計の使用を不要にし得るという効果
が生ずる。The method for detecting the operating state of a turbo-molecular pump according to the present invention is configured as described above. Therefore, in the method for detecting the operating state of a turbo-molecular pump according to the present invention, pressure and flow rate can be accurately determined based on the control state of the motor. This has the effect of making it unnecessary to use a conventional vacuum gauge.
第１図、第２図及び第３図はインバータ方式の誘導モー
タの回転数−トルク特性の説明図、第４図〜第７図はこ
の発明方法を実施するための回路構成を示すブロック図
、第８図及び第９図は直流モータにおける回転数−トル
ク特性の説明図、第１０図は圧力又は流量変換回路の実
施例のブロック図、第１１図は他の圧力又は流量変換回
路の実施例のブロック図、第１２図及び第１３図は圧力
又は流量変換回路の実施例のブロック図である。
特許出願人 日本フェロ−フルイデイクス株式会
社
回に数
第４図
第５図
第６図
第７図FIGS. 1, 2, and 3 are explanatory diagrams of the rotation speed-torque characteristics of an inverter-type induction motor, and FIGS. 4 to 7 are block diagrams showing the circuit configuration for carrying out the method of the present invention, Figures 8 and 9 are explanatory diagrams of the rotation speed-torque characteristics in a DC motor, Figure 10 is a block diagram of an embodiment of a pressure or flow rate conversion circuit, and Figure 11 is an example of another pressure or flow rate conversion circuit. 12 and 13 are block diagrams of embodiments of pressure or flow rate conversion circuits. Patent Applicant Nippon Ferro-Fluidix Co., Ltd. Figure 4 Figure 5 Figure 6 Figure 7
Claims (1)
負荷状態を検出し、この負荷状態をフィードバックして
回転翼を一定回転数で回転させるべくターボ分子ポンプ
を構成し、さらに上記負荷状態に見合うモータ制御特性
値を把握し、これに基づいて圧力又は流量を検出するこ
とを特徴とするターボ分子ポンプの運転状態検出方法。 ２、インバータ制御方式の誘導モータを使用すると共に
、Ｖ／Ｆを一定に保持して回転数制御を行うべく構成し
、このときの回転数設定周波数と駆動周波数との差、あ
るいは負荷電流とモータ印加電圧との位相差を把握し、
これらを圧力又は流量に変換することを特徴とする第１
請求項記載のターボ分子ポンプの運転状態検出方法。 ３、インバータ方式の誘導モータを使用すると共に、Ｆ
を設定値にしたままモータ印加電圧を変化させて回転数
制御を行うべく構成し、さらにモータ印加電圧、インバ
ータの出力制御回路を流れる電流、あるいはインバータ
の出力制御電圧を把握し、これらを圧力又は流量に変換
することを特徴とする第１請求項記載のターボ分子ポン
プの運転状態検出方法。 ４、上記出力制御電圧がＰＬＬ方式によって得られるも
のであることを特徴とする第３請求項記載のターボ分子
ポンプの運転状態検出方法。 ５、直流モータを使用すると共に、モータ印加電圧を変
化させて回転数制御を行うべく構成し、さらにモータ印
加電圧制御回路の制御電圧、モータ印加電圧制御回路を
流れる電流、モータ印加電圧、あるいはモータを流れる
電流のいずれかを把握し、これらを圧力又は流量に変換
することを特徴とする第１請求項記載のターボ分子ポン
プの運転状態検出方法。[Claims] 1. A turbo molecular pump is configured to rotate the rotor blades with a motor, detect the load condition of the rotor blades, and feed back this load condition to rotate the rotor blades at a constant rotation speed. A method for detecting an operating state of a turbo-molecular pump, further comprising: determining a motor control characteristic value that matches the load state, and detecting pressure or flow rate based on this. 2. In addition to using an inverter-controlled induction motor, it is configured to control the rotation speed while keeping the V/F constant, and the difference between the rotation speed setting frequency and the drive frequency, or the load current and motor Understand the phase difference with the applied voltage,
The first method is characterized by converting these into pressure or flow rate.
A method for detecting the operating state of a turbomolecular pump according to the claims. 3. In addition to using an inverter type induction motor,
It is configured to control the rotation speed by changing the voltage applied to the motor while keeping it at the set value, and also to understand the voltage applied to the motor, the current flowing through the inverter's output control circuit, or the inverter's output control voltage, and adjust these to the pressure or 2. The method of detecting the operating state of a turbo-molecular pump according to claim 1, further comprising converting the flow rate into a flow rate. 4. The method for detecting the operating state of a turbo-molecular pump according to claim 3, wherein the output control voltage is obtained by a PLL method. 5. A DC motor is used, and the motor is configured to control the rotation speed by changing the voltage applied to the motor, and the control voltage of the motor applied voltage control circuit, the current flowing through the motor applied voltage control circuit, the motor applied voltage, or the motor 2. The method of detecting the operating state of a turbo-molecular pump according to claim 1, wherein the method comprises detecting any of the currents flowing through the pump and converting them into pressure or flow rate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23526788A JPH0282000A (en) | 1988-09-20 | 1988-09-20 | Operational condition detecting method for turbo molecular pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23526788A JPH0282000A (en) | 1988-09-20 | 1988-09-20 | Operational condition detecting method for turbo molecular pump |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0282000A true JPH0282000A (en) | 1990-03-22 |
Family
ID=16983561
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23526788A Pending JPH0282000A (en) | 1988-09-20 | 1988-09-20 | Operational condition detecting method for turbo molecular pump |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0282000A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0385393A (en) * | 1989-08-29 | 1991-04-10 | Ntn Corp | Motor control device for vacuum pump |
| JP2005290998A (en) * | 2004-03-31 | 2005-10-20 | Boc Edwards Kk | Vacuum pump, and control method thereof |
| CN100443864C (en) * | 2005-09-15 | 2008-12-17 | 比亚迪股份有限公司 | Vehicle air throttle air inflow test system and testing method |
| US8075698B2 (en) | 2002-08-30 | 2011-12-13 | Tokyo Electron Limited | Substrate processing unit, method of detecting end point of cleaning of substrate processing unit, and method of detecting end point of substrate processing |
| WO2018206843A1 (en) * | 2017-05-08 | 2018-11-15 | Lappeenrannan Teknillinen Yliopisto | A method and a control system for controlling a vacuum pump |
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|---|---|---|---|---|
| JPS495845A (en) * | 1972-05-10 | 1974-01-19 | ||
| JPS59221634A (en) * | 1983-05-31 | 1984-12-13 | Shimadzu Corp | Measuring method of degree of vacuum |
| JPS62162791A (en) * | 1986-01-13 | 1987-07-18 | Kawasaki Steel Corp | Airflow controlling method for blowing and exhausting device |
| JPS63176694A (en) * | 1987-01-14 | 1988-07-20 | Seiko Seiki Co Ltd | Measuring device for degree of vacuum in turbo molecular pump |
-
1988
- 1988-09-20 JP JP23526788A patent/JPH0282000A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS495845A (en) * | 1972-05-10 | 1974-01-19 | ||
| JPS59221634A (en) * | 1983-05-31 | 1984-12-13 | Shimadzu Corp | Measuring method of degree of vacuum |
| JPS62162791A (en) * | 1986-01-13 | 1987-07-18 | Kawasaki Steel Corp | Airflow controlling method for blowing and exhausting device |
| JPS63176694A (en) * | 1987-01-14 | 1988-07-20 | Seiko Seiki Co Ltd | Measuring device for degree of vacuum in turbo molecular pump |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0385393A (en) * | 1989-08-29 | 1991-04-10 | Ntn Corp | Motor control device for vacuum pump |
| US8075698B2 (en) | 2002-08-30 | 2011-12-13 | Tokyo Electron Limited | Substrate processing unit, method of detecting end point of cleaning of substrate processing unit, and method of detecting end point of substrate processing |
| JP2005290998A (en) * | 2004-03-31 | 2005-10-20 | Boc Edwards Kk | Vacuum pump, and control method thereof |
| JP4558367B2 (en) * | 2004-03-31 | 2010-10-06 | エドワーズ株式会社 | Vacuum pump and control method thereof |
| CN100443864C (en) * | 2005-09-15 | 2008-12-17 | 比亚迪股份有限公司 | Vehicle air throttle air inflow test system and testing method |
| WO2018206843A1 (en) * | 2017-05-08 | 2018-11-15 | Lappeenrannan Teknillinen Yliopisto | A method and a control system for controlling a vacuum pump |
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