JPS60253982A - Circuit for measuring characteristic of servo circuit - Google Patents
Circuit for measuring characteristic of servo circuitInfo
- Publication number
- JPS60253982A JPS60253982A JP59111798A JP11179884A JPS60253982A JP S60253982 A JPS60253982 A JP S60253982A JP 59111798 A JP59111798 A JP 59111798A JP 11179884 A JP11179884 A JP 11179884A JP S60253982 A JPS60253982 A JP S60253982A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- servo
- amplifier
- resistor
- analyzer
- 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.)
- Granted
Links
Landscapes
- Measurement Of Resistance Or Impedance (AREA)
- Testing And Monitoring For Control Systems (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、コンパクトディスク（ＣＤ）プレーヤ等で使
用されるサーボ回路の開ループ伝達関数測定用回路に関
する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a circuit for measuring an open-loop transfer function of a servo circuit used in a compact disc (CD) player or the like.
ＣＤプレーヤ等におけるサーボ回路の安定度は、一般に
開ループ伝達関数における利得余裕と位相 −余裕によ
ってチェックされる。サーボ回路そのものは閉ループ構
成になっているため、その開ループ伝達関数の測定には
ループ切断等の工夫を要する。しかし、ＣＤプレーヤ等
のＤＣ利得の非常に高いサーボ回路の開ループ伝達関数
は、原理的に第３図のように閉ループ状態で測定できる
。但し、このためには測定対象とするサーボ回路１のル
ープ内に、測定時のみ必要な加算回路２を予め挿入して
お（必要がある。３は希望周波数の正弦波を出力する信
号発生器出力端Ｓと２つの分析入力端Ａ、Ｂを有するサ
ーボアナライザで、測定時には図示のような結線をする
。サーボアナライザ３は２チヤンネルのＦＦＴアナライ
ザで、サーボ回路１の端子Ｕに現われる信号の時間変化
ｕ （ｔｌをフーリエ変換した値と、端子■に現われる
信号の時間変化ｖ （１１をフーリエ変換した値からそ
れらの振幅比と位相差を測定する。ＣＤプレーヤに用い
られるサーボ回路には、ディスクの回転制御を対象とす
るものや、ディスクと光学ピンクアップの位置制御を対
象とするものがあり、いずれも高度の安定性が要求され
る。The stability of servo circuits in CD players and the like is generally checked by the gain margin and phase margin in the open loop transfer function. Since the servo circuit itself has a closed loop configuration, measures such as cutting the loop are required to measure its open loop transfer function. However, the open-loop transfer function of a servo circuit with a very high DC gain, such as a CD player, can in principle be measured in a closed-loop state as shown in FIG. However, in order to do this, it is necessary to insert in advance an adder circuit 2, which is required only during measurement, into the loop of the servo circuit 1 to be measured. 3 is a signal generator that outputs a sine wave of the desired frequency. This is a servo analyzer that has an output terminal S and two analysis input terminals A and B, and when making measurements, connect them as shown in the figure.The servo analyzer 3 is a two-channel FFT analyzer, and the time of the signal appearing at the terminal U of the servo circuit 1 is The amplitude ratio and phase difference are measured from the Fourier-transformed value of the change u (tl) and the Fourier-transformed value of the signal appearing at the terminal ■v (11). Some target the rotational control of the disk, while others target the positional control of the disk and optical pink-up, and both require a high degree of stability.
加算回路２は等価的に加算器２１と利得−１の反転増幅
器２２として表わされるが、具体的には第４図のように
構成される。つまり、２３は非反転端子（＋）を接地し
たＯＰアンプで、その出力が出力端Ｕとなる。このＯＰ
アンプ２３の出力端から反転端子（−）の間に帰還抵抗
Ｒ３を接続し、且つ該反転端子に抵抗Ｒ２を介してルー
プ人力Ｖを、また抵抗ＲＩを介してアナライザ出力Ｓを
供給する構成とすると、Ｒ＋ ＝Ｒ２＝Ｒ３の条件で第
３図の加算回路２が構成される。The adder circuit 2 is equivalently represented as an adder 21 and an inverting amplifier 22 with a gain of -1, and is specifically constructed as shown in FIG. That is, 23 is an OP amplifier whose non-inverting terminal (+) is grounded, and its output becomes the output terminal U. This OP
A feedback resistor R3 is connected between the output terminal of the amplifier 23 and the inverting terminal (-), and the loop human power V is supplied to the inverting terminal via the resistor R2, and the analyzer output S is supplied via the resistor RI. Then, the adder circuit 2 of FIG. 3 is configured under the condition of R+=R2=R3.
サーボ回路１は外部人力Ｘを安定化して外部出力ｙを得
るもので、Ｇｌ、Ｇ２は分割して示すループゲインであ
る。このサーボ回路の開ループ伝達関数Ｇｏは加算回路
２の出力端子ＵからＧ ２ 。The servo circuit 1 stabilizes an external human power X to obtain an external output y, and Gl and G2 are loop gains shown separately. The open loop transfer function Go of this servo circuit is G 2 from the output terminal U of the adder circuit 2.
Ｇｌを通り入力端子■へ戻るものであるから、Ｇｏ ＝
Ｇｌ ・Ｇ２ ＝−
として表わされる。但し、加算回路２に反転増幅器２２
が挿入されているのでループゲインの一方は−０２にな
っている。Since it passes through Gl and returns to the input terminal ■, Go =
It is expressed as Gl·G2=-. However, an inverting amplifier 22 is added to the adder circuit 2.
is inserted, so one of the loop gains is -02.
上述した測定方式では部品点数の多い加算回路２を全て
のサーボ回路に予め備えさせておく必要があるので１台
毎の単価が高価になり、また小型化の妨げになる欠点が
ある。In the above-mentioned measurement method, since it is necessary to equip all the servo circuits with the adder circuit 2, which has a large number of parts, the unit price of each servo circuit is high, and there is a drawback that it impedes miniaturization.
本発明は測定対象となるサーボ回路には抵抗１本だけを
挿入しておく構成とすることによりサーボ回路の低価格
化および小型化を図り、測定に必要なループ開放用の回
路はアダプタ化してサーボアナライザと共に全てのサー
ボ回路で共用できるようにするものである。このため本
発明のサーボ回路特性測定回路は、閉ループを構成する
サーボ回路の開ループ伝達特性を２チヤンネルのサーボ
アナライザで測定するに際し、該閉ループを等価的に開
放するサーボ回路特性測定用回路において、該閉ループ
の開放すべき個所に予め挿入された抵抗と、該抵抗の入
力端例の信号と該サーボアナライザの出力信号とを加算
する機能を有した単一利得の第１の反転増幅器と、該第
１の反転増幅器の出力を更に反転して該抵抗の出力端側
に供給する単一利得の第２の反転増幅器とを備え、該第
１および第２の反転増幅器からなる単一利得の非反転増
幅系をアダプタ回路とし、更に該アダプタ回路を該サー
ボ回路およびサーボアナライザに対し測定時にのみ着脱
自在に接続させる構成とすると共に、該第１の反転増幅
器の出力および該抵抗の入力端側の信号をそれぞれ該ア
ダプタ回路を通して該サーボアナライザの２入力端に供
給するようにしてなることを特徴とするものである。The present invention aims to reduce the cost and size of the servo circuit by inserting only one resistor into the servo circuit to be measured, and converts the loop opening circuit necessary for measurement into an adapter. This allows it to be shared by all servo circuits together with the servo analyzer. For this reason, the servo circuit characteristic measuring circuit of the present invention is a servo circuit characteristic measuring circuit that equivalently opens the closed loop when measuring the open loop transfer characteristic of the servo circuit constituting the closed loop using a two-channel servo analyzer. a resistor inserted in advance at a point where the closed loop should be opened; a first inverting amplifier with a unity gain having a function of adding the signal at the input terminal of the resistor and the output signal of the servo analyzer; a second inverting amplifier with a unity gain which further inverts the output of the first inverting amplifier and supplies the inverted output to the output end side of the resistor, the inverter with a unity gain consisting of the first and second inverting amplifiers; The inverting amplifier system is an adapter circuit, and the adapter circuit is configured to be detachably connected to the servo circuit and servo analyzer only during measurement, and the output of the first inverting amplifier and the input terminal side of the resistor are The present invention is characterized in that signals are supplied to two input terminals of the servo analyzer through the adapter circuits, respectively.
サーボアナライザとサーボ回路の間にループ開放用のア
ダプタを介在させる方法であると、サーボ回路のループ
内には僅かな部品を追加するだけで済み、各サーボ回路
の小型化および低価格化が図れる。If a loop opening adapter is interposed between the servo analyzer and the servo circuit, only a few components will be added to the servo circuit loop, making each servo circuit smaller and cheaper. .
以下、図面を参照しながら本発明の詳細な説明する。 Hereinafter, the present invention will be described in detail with reference to the drawings.
第１図は本発明の一実施例で、４はループ開放用のアダ
プタ回路である。このアダプタ回路４はサーボ回路１と
サーボアナライザ３ （第３図参照）の間に着脱自在に
介在するものであるが、その動作原理を第２図で説明す
る。同図は単一利得非反転アンプ４′に関する説明図で
、ＯＰアンプ４１と入力抵抗Ｒ４および帰還抵抗Ｒ５で
利得−１の反転増幅器を構成しくＲａ−Ｒ５）、またＯ
Ｐアンプ４２と入力抵抗Ｒ６および帰還抵抗Ｒ７で利得
−１の反転増幅器を構成しくＲａ＝Ｒ７）、これらを縦
続接続して全体として利得１の非反転増幅器４′を構成
している。この非反転増幅器４′に出力インピダンスＲ
ｇの信号源ｅｏを接続し、その入出力端間にＲｓなる抵
抗を接続したと仮定した場合、Ｒｇ＜Ｒｓであれば抵抗
Ｒｓが増幅器４′に与える影響を無視できる。つまり、
抵抗Ｒ３の部分は増幅器４′にとって開放されているこ
とと等価である。FIG. 1 shows an embodiment of the present invention, and 4 is an adapter circuit for opening the loop. This adapter circuit 4 is detachably interposed between the servo circuit 1 and the servo analyzer 3 (see FIG. 3), and its operating principle will be explained with reference to FIG. This figure is an explanatory diagram regarding the single gain non-inverting amplifier 4', in which the OP amplifier 41, input resistor R4, and feedback resistor R5 constitute an inverting amplifier with a gain of -1 (Ra-R5), and the
The P amplifier 42, input resistor R6, and feedback resistor R7 constitute an inverting amplifier with a gain of -1 (Ra=R7), and these are connected in cascade to constitute a non-inverting amplifier 4' with a gain of 1 as a whole. This non-inverting amplifier 4' has an output impedance R
Assuming that a signal source eo of g is connected and a resistor Rs is connected between its input and output terminals, the influence of the resistor Rs on the amplifier 4' can be ignored if Rg<Rs. In other words,
The portion of resistor R3 is equivalent to being open to amplifier 4'.
この原理に基づくのが第１図のアダプタ回路４で、その
抵抗Ｒ９〜Ｒ１２は第２図の抵抗Ｒ４〜Ｒ７に対応する
。アダプタ回路４としては、初段の反転増幅器４１の入
力抵抗Ｒ９の開放端Ｖをサーボアナライザ３のＢ入力お
よびサーボ回路１の端子１１に接続する。また次段の反
転増幅器４２の出力端をサーボ回路１の端子１２に接続
する。The adapter circuit 4 of FIG. 1 is based on this principle, and its resistors R9 to R12 correspond to the resistors R4 to R7 of FIG. 2. As the adapter circuit 4, the open end V of the input resistor R9 of the first-stage inverting amplifier 41 is connected to the B input of the servo analyzer 3 and the terminal 11 of the servo circuit 1. Further, the output terminal of the next stage inverting amplifier 42 is connected to the terminal 12 of the servo circuit 1.
これらの端子１１．１２は前述した抵抗Ｒｓをサーボ回
路１のループ内に挿入したとき、その抵抗の両端に接続
されたものである。また初段の反転増幅器４１の出力端
Ｕはサーボアナライザ３の六入力に接続され、更にその
反転入力端（−）は抵抗Ｒ８を介して該アナライザのＳ
出力に接続される。These terminals 11 and 12 are connected to both ends of the resistor Rs when the resistor Rs is inserted into the loop of the servo circuit 1. The output terminal U of the first-stage inverting amplifier 41 is connected to the six inputs of the servo analyzer 3, and the inverting input terminal (-) is connected to the S of the analyzer through a resistor R8.
Connected to the output.
上記構成において、Ｒｅ＝Ｒ９＝Ｒ１０：＞Ｚ。In the above configuration, Re=R9=R10:>Z.
に設定すると、抵抗Ｒ８〜ＲＩＯとＯＰアンプ４１は第
４図と同様の加算回路を構成する。またＲ１、−Ｒ１２
に設定すると抵抗Ｒ１１、Ｒ１２とＯＰアンプ４２は利
得−１の反転増幅器を構成するので、サーボ回路１２の
後段回路のゲインは非反転のＧ２で済む。ＺＩＮはこの
後段回路の入カインピダンスであり、また上述のＺＯは
ゲインＧ１の前段回路の出力インビダンスであるが、こ
こでＺＯ＜Ｒ３＜ＺＩＮを満すようにＲ５の抵抗値を設
定すると、アダプタ回路４の接続時に抵抗Ｒ３の部分は
第２図で説明したように等価的にオープン状態とみなす
ことができる。このために、ＺＯが数Ω、ＺＩＮが１０
０に〜ＩＭΩであるとすればＲｓをＩＫ〜ＩＯＫΩ程度
に設定し、アダプタ接続時の抵抗分割の影響が極力臼な
いようにする。尚、アダプタ回路４の非接続時に抵抗Ｒ
３がループ内に存在しても系の安定性に支障がないこと
は明らかである。When set to , the resistors R8 to RIO and the OP amplifier 41 constitute an adder circuit similar to that shown in FIG. Also R1, -R12
When set to , the resistors R11 and R12 and the OP amplifier 42 form an inverting amplifier with a gain of -1, so the gain of the circuit subsequent to the servo circuit 12 can be set to non-inverting G2. ZIN is the input impedance of this subsequent stage circuit, and ZO mentioned above is the output impedance of the previous stage circuit with gain G1, but if the resistance value of R5 is set to satisfy ZO<R3<ZIN, then When the adapter circuit 4 is connected, the resistor R3 can be equivalently considered to be in an open state as explained in FIG. For this reason, ZO is several Ω and ZIN is 10
0 to IMΩ, set Rs to about IK to IOKΩ to minimize the influence of resistance division when connecting the adapter. In addition, when the adapter circuit 4 is disconnected, the resistor R
It is clear that the presence of 3 in the loop does not affect the stability of the system.
以上述べたように本発明によれば、サーボアナライザを
用いてサーボ回路の開ループ伝達特性を測定する際に、
該サーボ回路の閉ループを等価的に開ループにする回路
の大部分をアダプタ化して全てのサーボ回路で共通使用
できるようにし、各号−水回路には抵抗１本だけを挿入
しておくようにしたので、サーボ回路側の構成が簡単に
なり、小型化および低価格化が図れる。また、アダプタ
回路とサーボアナライザ、サーボ回路との各接続部をコ
ネクタ、プラグイン方式等にしておけば測定時の作業性
は著しく簡単である。As described above, according to the present invention, when measuring the open loop transfer characteristics of a servo circuit using a servo analyzer,
Most of the circuits that make the closed loop of the servo circuit into an open loop are made into adapters so that they can be used commonly in all servo circuits, and only one resistor is inserted in each water circuit. This simplifies the configuration of the servo circuit, making it possible to reduce the size and cost. Furthermore, if the connection parts between the adapter circuit, servo analyzer, and servo circuit are connected by connectors, plug-in systems, etc., the workability during measurement is significantly simplified.
第１図は本発明の一実施例を示す回路図、第２図はその
原理を説明するための回路図、第３図は従来のサーボ回
路の開ループ伝達関数測定系の構成図、第４図はサーボ
回路に挿入される従来の測定用回路の構成図である。
図中、１はサーボ回路、３はサーボアナライザ、４はル
ープ開放用アダプタ回路、４１は第１の反転増幅器、４
２は第２の反転増幅器、Ｒ９は抵抗である。
出 願 人 富士通テン株式会社
代理人弁理士 青 柳 稔FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a circuit diagram for explaining its principle, FIG. 3 is a configuration diagram of a conventional open loop transfer function measurement system of a servo circuit, and FIG. The figure is a configuration diagram of a conventional measurement circuit inserted into a servo circuit. In the figure, 1 is a servo circuit, 3 is a servo analyzer, 4 is a loop opening adapter circuit, 41 is a first inverting amplifier, 4
2 is a second inverting amplifier, and R9 is a resistor. Applicant: Minoru Aoyagi, Patent Attorney, Fujitsu Ten Limited
Claims (1)
チヤンネルのサーボアナライザで測定するに際し、該閉
ループを等測的に開放するサーボ回路特性測定用回路に
おいて、該閉ループの開放すべき個所に予め挿入された
抵抗と、該抵抗の入力端側の信号と該サーボアナライザ
の出力信号とを加算する機能を有した単一利得の第１の
反転増幅器と、該第１の反転増幅器の出力を更に反転し
て該抵抗の出力端側に供給する単一利得の第２の反転増
幅器とを備え、該第１および第２の反転増幅器からなる
単一利得の非反転増幅系をアダプタ回路とし、更に該ア
ダプタ回路を該サーボ回路およびサーボアナライザに対
し測定時にのみ着脱自在に接続させる構成とすると共に
、該第１の反転増幅器の出力および該抵抗の入力端例の
信号をそれぞれ該アダプタ回路を通して該サーボアナラ
イザの２入力端に供給するようにしてなることを特徴と
するサーボ回路特性測定用回路。The open loop transfer characteristics of the servo circuit that constitutes the closed loop are
When measuring with a channel servo analyzer, in a circuit for measuring servo circuit characteristics that isometrically opens the closed loop, a resistor is inserted in advance at the point where the closed loop is to be opened, and a signal at the input end of the resistor is connected to the circuit. a first inverting amplifier with a unity gain having a function of adding the output signal of the servo analyzer; and a unity gain inverting the output of the first inverting amplifier and supplying the inverted output to the output end of the resistor. and a second inverting amplifier, a single-gain non-inverting amplification system consisting of the first and second inverting amplifiers is used as an adapter circuit, and the adapter circuit is connected to the servo circuit and the servo analyzer only during measurement. The servo analyzer is configured to be connected detachably, and the output of the first inverting amplifier and the signals of the input terminal of the resistor are respectively supplied to the two input terminals of the servo analyzer through the adapter circuit. Circuit for measuring servo circuit characteristics.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59111798A JPS60253982A (en) | 1984-05-31 | 1984-05-31 | Circuit for measuring characteristic of servo circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59111798A JPS60253982A (en) | 1984-05-31 | 1984-05-31 | Circuit for measuring characteristic of servo circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60253982A true JPS60253982A (en) | 1985-12-14 |
| JPH0465989B2 JPH0465989B2 (en) | 1992-10-21 |
Family
ID=14570418
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59111798A Granted JPS60253982A (en) | 1984-05-31 | 1984-05-31 | Circuit for measuring characteristic of servo circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60253982A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014228930A (en) * | 2013-05-20 | 2014-12-08 | 株式会社荏原製作所 | Servo controller |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP4321772A1 (en) | 2022-08-10 | 2024-02-14 | Able Human Motion, S.L. | Backdrivable actuator for exoskeleton |
-
1984
- 1984-05-31 JP JP59111798A patent/JPS60253982A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014228930A (en) * | 2013-05-20 | 2014-12-08 | 株式会社荏原製作所 | Servo controller |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0465989B2 (en) | 1992-10-21 |
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