JP3567628B2

JP3567628B2 - Servo controller

Info

Publication number: JP3567628B2
Application number: JP19127096A
Authority: JP
Inventors: 務新美
Original assignee: Fuji Electric FA Components and Systems Co Ltd
Current assignee: Fuji Electric FA Components and Systems Co Ltd
Priority date: 1996-07-22
Filing date: 1996-07-22
Publication date: 2004-09-22
Anticipated expiration: 2016-07-22
Also published as: JPH1042582A

Description

【０００１】
【発明の属する技術分野】
この発明は、サーボモータを位置制御ループと速度制御ループと電流制御ループとにより制御するサーボコントローラに関する。
【０００２】
【従来の技術】
この種のサーボコントローラの従来のブロック構成図を図１０に示す。
図１０において、１は、例えば、永久磁石式同期電動機などのサーボモータ、２はサーボモータ１の位置および速度を検出するパルスジェネレータ（ＰＧ）、１０はサーボコントローラである。
【０００３】
サーボコントローラ１０は、位置制御ループを構成する偏差カウンタ１１と、偏差カウンタ１１の出力を速度指令値として速度制御ループを構成する速度調節速度調節器１２および速度検出器１３と、速度調節器１２の出力を電流指令値とし、この電流指令値に基づく電流制御ループ１４とを備えている。
サーボコントローラ１０の動作を、図１０を参照しつつ、以下に説明する。
【０００４】
外部より指令される位置指令値はパルス列で与えられ、偏差カウンタ１１では該パルス列の個々のパルスとパルスジェネレータ２のパルスとの偏差を積算し、この積算値（溜まりパルスと称する）を速度指令値として出力する。速度調節器１２では前記速度指令値と、パルスジェネレータ２と速度検出器１３とを介したサーボモータ１の速度検出値との偏差を速度調節部１２ａにより比例・積分演算し、この演算値を出力制限部１２ｂによりサーボモータ１の最大加速，減速電流以内に制限して、この値を電流指令値として出力する。この電流指令値を受ける電流調節部及びインバータなどの電力変換部からなる電流制御ループ１４では、サーボモータ１に所望の加速，減速電流または定常電流を流すようにしている。
【０００５】
【発明が解決しようとする課題】
上記従来のサーボコントローラ１０によると、例えばワークの送りにサーボモータ１を使用し、このワークをストッパに押し当てて前進できないような位置決めをする用途の場合（以下、当て止め停止と称する）、この当て止め停止時にワークをストッパに一定のスラストで押し当てるに必要なサーボモータ１の電流（トルク）を電流調節器１２の出力制限部１２ｂの制限値としていた。
【０００６】
そのために、前記当て止め停止時以外のワークの送りのときにも、前記制限値以内でサーボモータが動作をするので、送りのサイクルタイムが長くなるという問題があった。
この発明の目的は、上記問題点を解決するサーボコントローラを提供することにある。
【０００７】
【課題を解決するための手段】
サーボモータを位置制御ループと速度制御ループと電流制御ループとにより制御するサーボコントローラにおいて、
この第１の発明は、サーボモータの位置検出値と位置制御ループの位置偏差と電流制御ループの電流指令値とを入力し、該位置検出値の変化が零で且つ前記位置偏差が所定の値を越えた状態になり、さらにこの状態で前記電流指令値が最大値のまま所定の時間を経過したときに外部へその状態信号を出力する状態監視回路を備え、
また第２の発明は、サーボモータの速度検出値と速度制御ループの速度偏差と電流制御ループの電流指令値とを入力し、該速度検出値が零で且つ前記速度偏差が所定の値を越えた状態になり、さらにこの状態で前記電流指令値が最大値のまま所定の時間を経過したときに外部へその状態信号を出力する状態監視回路を備える。
【０００８】
第３〜７の発明は、前記サーボコントローラに前記第１の発明の状態監視回路を第１状態監視回路とし、前記第２の発明の状態監視回路を第２状態監視回路としてそれぞれ備え、
第３の発明は、さらに前記第１状態監視回路または第２状態監視回路のいずれか一方または双方が動作したときに前記電流指令値を最大値から所定の減少パターンで電流制限値まで減少させる電流制限値発生回路を備え、
第４の発明は、さらに前記第１状態監視回路または第２状態監視回路のいずれか一方または双方が動作したときに前記電流指令値を速度制御ループの出力値から外部電流指令値に切替え、該外部電流指令値は前記電流指令値の最大値から所定の減少パターンで新たな外部電流指令値まで減少させる電流指令値切替回路を備え、
第５の発明は、さらに前記第１状態監視回路または第２状態監視回路のいずれか一方または双方が動作したときに前記電流指令値を速度制御ループの出力値から外部電流指令値に切替え、該外部電流指令値は前記電流指令値の最大値から所定の減少パターンで新たな外部電流指令値まで減少させ、該新たな外部電流指令値に到達したときに位置制御ループの位置指令値を零に切替え、且つ該位置制御ループの偏差カウンタのカウンタ値を零にセットする切替・制御回路を備え、
第６の発明は、さらに前記第１状態監視回路または第２状態監視回路のいずれか一方または双方が動作したときに前記電流指令値を速度制御ループの出力値から外部電流指令値に切替え、該外部電流指令値は前記電流指令値の最大値から所定の減少パターンで新たな外部電流指令値まで減少させ、該新たな外部電流指令値に到達したときに速度制御ループの速度指令値を零に切替える切替・制御回路を備え、
第７の発明は、さらに前記第１状態監視回路または第２状態監視回路のいずれか一方または双方が動作したときに前記電流指令値を速度制御ループの出力値から外部電流指令値に切替え、該外部電流指令値は前記電流指令値の最大値から所定の減少パターンで新たな外部電流指令値まで減少させ、該新たな外部電流指令値に到達したときにサーボモータに付加されたブレーキを投入する切替・制御回路を備える。
【０００９】
この第１の発明によれば、サーボモータの位置検出値と位置制御ループの位置偏差と電流制御ループの電流指令値とにより前記当て止め停止状態を検知する。また第２の発明によれば、サーボモータの速度検出値と速度制御ループの速度偏差と電流制御ループの電流指令値とにより前記当て止め停止状態を検知する。さらに第３〜７の発明は、前記第１の発明の当て止め停止状態を検知する第１状態監視回路と、前記第２の発明の当て止め停止状態を検知する第２状態監視回路と、第１状態監視回路または第２状態監視回路が動作したときに電流制御ループの電流指令値をサーボモータの最大加速，減速電流より十分小さい値で動作させるように作用する。
【００１０】
【発明の実施の形態】
以下に記載するこの発明の実施例の説明において、図１０に示した従来のサーボコントローラと同一機能を有するものには同一符号を付している。
図１はこの発明の第１の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ２０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、状態監視回路２１とが備えられている。
【００１１】
図１に示す状態監視回路２１は第１〜第３の比較器とタイマとアンド素子とから構成され、サーボモータ１のパルスジェネレータ２を介して得られる位置検出値と偏差カウンタ１１の位置偏差と速度調節器１２の出力である電流指令値とを入力し、該位置検出値の変化が零になったことを第１比較器で検知し、且つ前記位置偏差が所定の値を越えたことを第２比較器で検知し、前記電流指令値がサーボモータ１の最大電流値のまま所定の時間を経過したことを第３比較器とタイマで検知し、第１比較器，第２比較器、タイマそれぞれの動作の論理積演算をアンド素子で行っている。すなわちアンド素子の条件が成立するときは前記当て止め停止状態である。なお、前記タイマの設定時間は、サーボモータ１の最大加速時間に基づいて調整される。
【００１２】
図２はこの発明の第２の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ３０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、状態監視回路３１とが備えられている。
図２に示す状態監視回路３１は第１〜第３の比較器とタイマとアンド素子とから構成され、サーボモータ１のパルスジェネレータ２と速度検出器１３とを介して得られる速度検出値と速度調節器１２の速度偏差と速度調節器１２の出力である電流指令値とを入力し、該速度検出値が零になったことを第１比較器で検知し、且つ前記速度偏差が所定の値を越えたことを第２比較器で検知し、前記電流指令値がサーボモータ１の最大電流値のまま所定の時間を経過したことを第３比較器とタイマで検知し、第１比較器，第２比較器、タイマそれぞれの動作の論理積演算をアンド素子で行っている。すなわちアンド素子の条件が成立するときは前記当て止め停止状態である。なお、前記タイマの設定時間は、サーボモータ１の最大加速時間に基づいて調整される。
【００１３】
図３はこの発明の第３の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ４０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、前記第１の実施例の状態監視回路２１と、前記第２の実施例の状態監視回路３１と、電流制限値発生回路４１とが備えられている。
【００１４】
図３に示す電流制限値発生回路４１には、状態監視回路２１または状態監視回路３１のいずれか一方または双方が動作したことを検知するオア素子と、該オア素子の動作により電圧調節器１２の出力制限部１２ｂの出力の電流指令値を最大値から所定の減少パターンで電流制限値（Ｉ_Ｌ）まで減少させるパターン発生回路とを備えている。
【００１５】
図４は、前記パターン発生回路の波形例を示し、図４（イ）はサーボモータ１の最大電流値からステップ状に電流制限値（Ｉ_Ｌ）まで減少させる例であり、図４（ロ）はサーボモータ１の最大電流値から直線状に電流制限値（Ｉ_Ｌ）まで減少させる例であり、図４（ハ）はサーボモータ１の最大電流値から一次遅れ波形状に電流制限値（Ｉ_Ｌ）まで減少させる例であり、いずれの場合にも電流制限値（Ｉ_Ｌ）は、サーボモータ１の最大電流値である最大加速，減速電流より十分小さい値とし、例えば当て止め停止時にワークをストッパに一定のスラストで押し当てるに必要なサーボモータ１の電流値に相当する値とする。
【００１６】
図５はこの発明の第４の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ５０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、前記第１の実施例の状態監視回路２１と、前記第２の実施例の状態監視回路３１と、電流指令値切替回路５１とが備えられている。
【００１７】
図５に示す電流制限値発生回路５１には、状態監視回路２１または状態監視回路３１のいずれか一方または双方が動作したことを検知するオア素子と、該オア素子の動作により電流制御ループ１４の電流指令値を電圧調節器１２の出力値から外部電流指令値（Ｉ_Ｓ）に切替えるスイッチと、電圧調節器１２の出力値から外部電流指令値（Ｉ_Ｓ）まで所定の減少パターンで減少させるパターン発生回路とを備えている。
【００１８】
図６は、前記パターン発生回路の波形例を示し、図６（イ）はサーボモータ１の最大電流値からステップ状に外部電流指令値（Ｉ_Ｓ）まで減少させる例であり、図６（ロ）はサーボモータ１の最大電流値から直線状に外部電流指令値（Ｉ_Ｓまで減少させる例であり、図６（ハ）はサーボモータ１の最大電流値から一次遅れ波形状に外部電流指令値（Ｉ_Ｓ）まで減少させる例であり、いずれの場合にも外部電流指令値（Ｉ_Ｓ）は、サーボモータ１の最大電流値である最大加速，減速電流より十分小さい値とし、例えば当て止め停止時にワークをストッパに一定のスラストで押し当てるに必要なサーボモータ１の電流値に相当する値とする。
【００１９】
図７はこの発明の第５の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ６０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、前記第１の実施例の状態監視回路２１と、前記第２の実施例の状態監視回路３１と、切替・制御回路６１と、切替スイッチ６２とが備えられている。
【００２０】
図７に示す切替・制御回路６１は、第４の実施例の電流指令値切替回路５１と同様の機能をし、外部電流指令値（Ｉ_Ｓ）を図６に示したいずれかの減少パターンで減少させ、最終的な外部電流指令値（Ｉ_Ｓ）に到達したことを比較器で検知し（図６参照）、この比較器が動作したときに偏差カウンタ１１の位置指令値を零に切替スイッチ６２で切替え、且つ偏差カウンタ１１の前記溜まりパルスを零にセットする動作をする。
【００２１】
図８はこの発明の第６の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ７０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、前記第１の実施例の状態監視回路２１と、前記第２の実施例の状態監視回路３１と、切替・制御回路７１と、切替スイッチ７２とが備えられている。
【００２２】
図８に示す切替・制御回路７１は、第４の実施例の電流指令値切替回路５１と同様の機能をし、外部電流指令値（Ｉ_Ｓ）を図６に示したいずれかの減少パターンで減少させ、最終的な外部電流指令値（Ｉ_Ｓ）に到達したことを比較器で検知し（図６参照）、この比較器が動作したときに速度調節器１２のの速度指令値を零に切替スイッチ７２で切替える動作をする。
【００２３】
図９はこの発明の第７の実施例を示すサーボコントローラのブロック構成図であり、このサーボコントローラ８０には偏差カウンタ１１と、速度調節器１２と、速度検出器１３と、電流制御ループ１４と、前記第１の実施例の状態監視回路２１と、前記第２の実施例の状態監視回路３１と、切替・制御回路８１とが備えられている。さらにサーボモータ１には機械ブレーキ１ａが付加されている。
【００２４】
図９に示す切替・制御回路８１は、第４の実施例の電流指令値切替回路５１と同様の機能をし、外部電流指令値（Ｉ_Ｓ）を図６に示したいずれかの減少パターンで減少させ、最終的な外部電流指令値（Ｉ_Ｓ）に到達したことを比較器で検知し（図６参照）、この比較器が動作したときに機械ブレーキ１ａを投入させる動作をする。
【００２５】
【発明の効果】
この発明によれば、サーボモータの位置検出値，位置制御ループの位置偏差または速度検出値，速度偏差と電流制御ループの電流指令値とにより前記当て止め停止状態を検知でき、該当て止め停止状態を検知したときに電流制御ループの電流指令値をサーボモータの最大加速，減速電流より十分小さい値で動作させるので、このサーボモータとサーボコントローラとを搬送器、メカフィードなどの機械設備に適用すれば好適である。
【図面の簡単な説明】
【図１】この発明の第１の実施例を示すサーボコントローラのブロック構成図
【図２】この発明の第２の実施例を示すサーボコントローラのブロック構成図
【図３】この発明の第３の実施例を示すサーボコントローラのブロック構成図
【図４】図３の動作説明図
【図５】この発明の第４の実施例を示すサーボコントローラのブロック構成図
【図６】図５の動作説明図
【図７】この発明の第５の実施例を示すサーボコントローラのブロック構成図
【図８】この発明の第６の実施例を示すサーボコントローラのブロック構成図
【図９】この発明の第７の実施例を示すサーボコントローラのブロック構成図
【図１０】従来例を示すサーボコントローラのブロック構成図
【符号の説明】
１…サーボモータ、１ａ…ブレーキ、２…パルスジェネレータ、１０，２０，３０，４０，５０，６０，７０，８０…サーボコントローラ、１１…偏差カウンタ、１２…速度調節器、１３…速度検出器、１４…電流制御ループ、２１，３１…状態監視回路、４１…電流制限値発生回路、５１…電流指令値切替回路、６１，７１，８１…切替・制御回路、６２，７２…切替スイッチ。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop.
[0002]
[Prior art]
FIG. 10 shows a block diagram of a conventional servo controller of this type.
In FIG. 10, reference numeral 1 denotes a servomotor such as a permanent magnet type synchronous motor, etc., 2 denotes a pulse generator (PG) for detecting the position and speed of the servomotor 1, and 10 denotes a servo controller.
[0003]
The servo controller 10 includes a deviation counter 11 that forms a position control loop, a speed adjustment speed controller 12 and a speed detector 13 that form a speed control loop using the output of the deviation counter 11 as a speed command value. An output is a current command value, and a current control loop 14 based on the current command value is provided.
The operation of the servo controller 10 will be described below with reference to FIG.
[0004]
A position command value externally given is given in the form of a pulse train, and the deviation counter 11 integrates the deviation between each pulse of the pulse train and the pulse of the pulse generator 2, and calculates the accumulated value (called the accumulated pulse) as the speed command value. Is output as In the speed controller 12, a deviation between the speed command value and the detected speed value of the servo motor 1 via the pulse generator 2 and the speed detector 13 is proportionally and integratedly calculated by a speed control unit 12a, and the calculated value is output. The limiting unit 12b limits the current within the maximum acceleration and deceleration current of the servomotor 1, and outputs this value as a current command value. In a current control loop 14 including a current control unit that receives the current command value and a power conversion unit such as an inverter, a desired acceleration, deceleration current, or steady current is supplied to the servomotor 1.
[0005]
[Problems to be solved by the invention]
According to the conventional servo controller 10 described above, for example, when the servomotor 1 is used for feeding a work, and the work is pressed against a stopper to perform positioning so that the work cannot be advanced (hereinafter, referred to as stop by stop). The current (torque) of the servomotor 1 required to press the work against the stopper with a constant thrust at the time of stopping the contact stop is set as the limit value of the output limiter 12b of the current controller 12.
[0006]
For this reason, even when the workpiece is fed at a time other than the stop time of the contact stop, the servo motor operates within the above-mentioned limit value, so that there is a problem that the cycle time of the feed becomes long.
An object of the present invention is to provide a servo controller that solves the above problems.
[0007]
[Means for Solving the Problems]
In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
In the first invention, a position detection value of a servomotor, a position deviation of a position control loop, and a current command value of a current control loop are input, and a change in the position detection value is zero and the position deviation is a predetermined value. A state monitoring circuit that outputs the state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in this state,
According to a second aspect of the present invention, a speed detection value of a servomotor, a speed deviation of a speed control loop, and a current command value of a current control loop are input, and the speed detection value is zero and the speed deviation exceeds a predetermined value. And a state monitoring circuit for outputting a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in this state.
[0008]
According to a third to seventh aspects of the present invention, the servo controller includes the state monitoring circuit of the first invention as a first state monitoring circuit, and the state monitoring circuit of the second invention as a second state monitoring circuit.
According to a third aspect of the present invention, there is further provided a current control device for reducing the current command value from a maximum value to a current limit value in a predetermined decreasing pattern when one or both of the first state monitoring circuit and the second state monitoring circuit operate. Equipped with a limit value generation circuit,
A fourth invention further switches the current command value from an output value of a speed control loop to an external current command value when one or both of the first state monitoring circuit and the second state monitoring circuit operate. The external current command value includes a current command value switching circuit that reduces the maximum value of the current command value to a new external current command value in a predetermined decrease pattern,
The fifth invention further switches the current command value from an output value of a speed control loop to an external current command value when one or both of the first state monitoring circuit and the second state monitoring circuit operate. The external current command value is reduced from the maximum value of the current command value to a new external current command value in a predetermined decreasing pattern, and when the new external current command value is reached, the position command value of the position control loop is set to zero. A switching / control circuit for switching, and setting a counter value of a deviation counter of the position control loop to zero,
The sixth invention further switches the current command value from an output value of a speed control loop to an external current command value when one or both of the first state monitoring circuit and the second state monitoring circuit operate. The external current command value is reduced from the maximum value of the current command value to a new external current command value in a predetermined decreasing pattern, and when the new external current command value is reached, the speed command value of the speed control loop is reduced to zero. Equipped with a switching / control circuit for switching,
A seventh invention further switches the current command value from an output value of a speed control loop to an external current command value when one or both of the first state monitoring circuit and the second state monitoring circuit operate. The external current command value is reduced from the maximum value of the current command value to a new external current command value in a predetermined decreasing pattern, and when the new external current command value is reached, the brake added to the servomotor is turned on. A switching / control circuit is provided.
[0009]
According to the first aspect, the contact stop state is detected based on the position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop. Further, according to the second aspect, the hit stop state is detected based on the detected speed of the servomotor, the speed deviation of the speed control loop, and the current command value of the current control loop. Further, the third to seventh inventions include a first state monitoring circuit for detecting the contact stop state of the first invention, a second state monitoring circuit for detecting the contact stop state of the second invention, When the first state monitoring circuit or the second state monitoring circuit operates, the current control loop operates so that the current command value is operated at a value sufficiently smaller than the maximum acceleration and deceleration current of the servomotor.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
In the following description of the embodiments of the present invention, components having the same functions as those of the conventional servo controller shown in FIG.
FIG. 1 is a block diagram showing a servo controller according to a first embodiment of the present invention. The servo controller 20 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, , A state monitoring circuit 21.
[0011]
The state monitoring circuit 21 shown in FIG. 1 includes first to third comparators, a timer, and an AND element, and detects a position detection value obtained via the pulse generator 2 of the servo motor 1 and a position deviation of the deviation counter 11. A current command value, which is the output of the speed controller 12, is input, the first comparator detects that the change in the position detection value has become zero, and determines that the position deviation has exceeded a predetermined value. The third comparator and the timer detect that a predetermined time has elapsed while the current command value remains at the maximum current value of the servomotor 1 by the second comparator, and the first comparator, the second comparator, The AND operation of each operation of the timer is performed by an AND element. That is, when the condition of the AND element is satisfied, the contact stop state is set. The set time of the timer is adjusted based on the maximum acceleration time of the servo motor 1.
[0012]
FIG. 2 is a block diagram showing a servo controller according to a second embodiment of the present invention. The servo controller 30 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, , A state monitoring circuit 31.
The state monitoring circuit 31 shown in FIG. 2 includes first to third comparators, a timer, and an AND element, and detects a speed detection value and a speed obtained through the pulse generator 2 and the speed detector 13 of the servo motor 1. A speed deviation of the controller 12 and a current command value which is an output of the speed controller 12 are input, the first comparator detects that the detected speed value has become zero, and the speed deviation is a predetermined value. Is detected by a second comparator, and a third comparator and a timer detect that a predetermined time has elapsed while the current command value remains at the maximum current value of the servo motor 1, and the first comparator, The AND operation of the operations of the second comparator and the timer is performed by an AND element. That is, when the condition of the AND element is satisfied, the contact stop state is set. The set time of the timer is adjusted based on the maximum acceleration time of the servo motor 1.
[0013]
FIG. 3 is a block diagram showing a servo controller according to a third embodiment of the present invention. The servo controller 40 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, The state monitoring circuit 21 of the first embodiment, the state monitoring circuit 31 of the second embodiment, and the current limit value generation circuit 41 are provided.
[0014]
The current limit value generating circuit 41 shown in FIG. 3 includes an OR element that detects that one or both of the state monitoring circuit 21 and the state monitoring circuit 31 has operated, and an operation of the voltage regulator 12 by the operation of the OR element. A pattern generation circuit for reducing the current command value of the output of the output limiting unit 12b from the maximum value to the current limit value (I _L ) in a predetermined decreasing pattern.
[0015]
FIG. 4 shows an example of the waveform of the pattern generation circuit. FIG. 4A shows an example in which the maximum current value of the servomotor 1 is reduced stepwise to a current limit value (I _L ). FIG. 4C shows an example in which the maximum current value of the servomotor 1 is linearly reduced to a current limit value (I _L ). FIG. _L ), and in any case, the current limit value (I _L ) is set to a value sufficiently smaller than the maximum acceleration and deceleration currents, which are the maximum current values of the servo motor 1. A value corresponding to the current value of the servo motor 1 necessary to press the stopper with a constant thrust is used.
[0016]
FIG. 5 is a block diagram showing a servo controller according to a fourth embodiment of the present invention. The servo controller 50 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, The status monitoring circuit 21 of the first embodiment, the status monitoring circuit 31 of the second embodiment, and a current command value switching circuit 51 are provided.
[0017]
The current limit value generating circuit 51 shown in FIG. 5 includes an OR element for detecting that one or both of the state monitoring circuit 21 and the state monitoring circuit 31 has operated, and an operation of the current control loop 14 by the operation of the OR element. a switch for switching the current command value from the output values of the voltage regulator 12 to an external current instruction value (I _S), a pattern to be reduced at a predetermined reduction pattern from the output value of the voltage regulator 12 to an external current instruction value (I _S) A generating circuit.
[0018]
FIG. 6 shows a waveform example of the pattern generation circuit. FIG. 6A shows an example in which the maximum current value of the servomotor 1 is reduced stepwise to the external current command value (I _S ). ) is (an example reduced to I _S, FIG. 6 (c) linearly external current command value from the maximum current value of the servo motor 1 is an external current command value to a primary delay wave shape from the maximum current value of the servo motor 1 (I _S) is an example of reducing to an external current command value in either case (I _S), the maximum acceleration is a maximum current value of the servo motor 1, and sufficiently smaller than the deceleration current, for example Bumping stop At times, the value is set to a value corresponding to the current value of the servo motor 1 necessary for pressing the work against the stopper with a constant thrust.
[0019]
FIG. 7 is a block diagram of a servo controller according to a fifth embodiment of the present invention. The servo controller 60 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, The status monitor circuit 21 of the first embodiment, the status monitor circuit 31 of the second embodiment, a switching / control circuit 61, and a switch 62 are provided.
[0020]
The switching / control circuit 61 shown in FIG. 7 has the same function as the current command value switching circuit 51 of the fourth embodiment, and changes the external current command value (I _S ) in one of the decreasing patterns shown in FIG. The comparator detects that it has reached the final external current command value (I _S ) (see FIG. 6), and when the comparator operates, sets the position command value of the deviation counter 11 to zero. The operation is switched at 62 and the accumulated pulse of the deviation counter 11 is set to zero.
[0021]
FIG. 8 is a block diagram showing a servo controller according to a sixth embodiment of the present invention. The servo controller 70 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, The status monitor circuit 21 of the first embodiment, the status monitor circuit 31 of the second embodiment, a switching / control circuit 71, and a switch 72 are provided.
[0022]
The switching / control circuit 71 shown in FIG. 8 has the same function as the current command value switching circuit 51 of the fourth embodiment, and changes the external current command value (I _S ) in one of the decreasing patterns shown in FIG. When the comparator reaches the final external current command value (I _S ) (see FIG. 6), the speed command value of the speed controller 12 is reduced to zero when the comparator operates. The switching operation is performed by the changeover switch 72.
[0023]
FIG. 9 is a block diagram showing a servo controller according to a seventh embodiment of the present invention. The servo controller 80 includes a deviation counter 11, a speed controller 12, a speed detector 13, a current control loop 14, The status monitor circuit 21 of the first embodiment, the status monitor circuit 31 of the second embodiment, and a switching / control circuit 81 are provided. Further, the servomotor 1 is provided with a mechanical brake 1a.
[0024]
The switching / control circuit 81 shown in FIG. 9 has the same function as the current command value switching circuit 51 of the fourth embodiment, and changes the external current command value (I _S ) in one of the decreasing patterns shown in FIG. Then, the comparator detects that it has reached the final external current command value (I _S ) (see FIG. 6), and operates the mechanical brake 1a when the comparator operates.
[0025]
【The invention's effect】
According to the present invention, the hit stop state can be detected based on the position detection value of the servomotor, the position deviation or speed detection value of the position control loop, the speed deviation and the current command value of the current control loop, and the stop stop state can be detected accordingly. When the current is detected, the current command value of the current control loop is operated with a value sufficiently smaller than the maximum acceleration and deceleration current of the servo motor. Therefore, apply this servo motor and servo controller to mechanical equipment such as a transporter and a mechanical feed. It is suitable.
[Brief description of the drawings]
FIG. 1 is a block diagram of a servo controller showing a first embodiment of the present invention; FIG. 2 is a block diagram of a servo controller showing a second embodiment of the present invention; FIG. FIG. 4 is a block diagram of a servo controller showing an embodiment. FIG. 4 is an operation explanatory diagram of FIG. 3. FIG. 5 is a block diagram of a servo controller showing a fourth embodiment of the present invention. FIG. 7 is a block diagram of a servo controller according to a fifth embodiment of the present invention; FIG. 8 is a block diagram of a servo controller according to a sixth embodiment of the present invention; FIG. 10 is a block diagram of a servo controller showing an embodiment. FIG. 10 is a block diagram of a servo controller showing a conventional example.
DESCRIPTION OF SYMBOLS 1 ... Servo motor, 1a ... Brake, 2 ... Pulse generator, 10, 20, 30, 40, 50, 60, 70, 80 ... Servo controller, 11 ... Deviation counter, 12 ... Speed adjuster, 13 ... Speed detector, 14: current control loop, 21, 31: state monitoring circuit, 41: current limit value generation circuit, 51: current command value switching circuit, 61, 71, 81: switching / control circuit, 62, 72: switching switch.

Claims

In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
The position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop are input, and the change in the position detection value is zero and the position deviation exceeds a predetermined value. The servo controller further comprises a state monitoring circuit for outputting a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in this state.

In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
A speed detection value of the servo motor, a speed deviation of the speed control loop, and a current command value of the current control loop are inputted, and the speed detection value becomes zero and the speed deviation exceeds a predetermined value. A servo controller comprising: a state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in the state.

In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
The position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop are input, and the change in the position detection value is zero and the position deviation exceeds a predetermined value. Further, in this state, a first state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value,
A speed detection value of the servo motor, a speed deviation of the speed control loop, and a current command value of the current control loop are inputted, and the speed detection value becomes zero and the speed deviation exceeds a predetermined value. A second state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in a state,
A current limit value generation circuit that reduces the current command value from a maximum value to a current limit value in a predetermined decrease pattern when one or both of the first state monitoring circuit and the second state monitoring circuit operate;
A servo controller comprising:

In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
The position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop are input, and the change in the position detection value is zero and the position deviation exceeds a predetermined value. Further, in this state, a first state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value,
A speed detection value of the servo motor, a speed deviation of the speed control loop, and a current command value of the current control loop are inputted, and the speed detection value becomes zero and the speed deviation exceeds a predetermined value. A second state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in a state,
When one or both of the first state monitoring circuit and the second state monitoring circuit operate, the current command value is switched from the output value of the speed control loop to the external current command value, and the external current command value is the current A current command value switching circuit that reduces the maximum command value to a new external current command value in a predetermined decreasing pattern;
A servo controller comprising:

In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
The position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop are input, and the change in the position detection value is zero and the position deviation exceeds a predetermined value. Further, in this state, a first state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value,
A speed detection value of the servo motor, a speed deviation of the speed control loop, and a current command value of the current control loop are inputted, and the speed detection value becomes zero and the speed deviation exceeds a predetermined value. A second state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in a state,
When one or both of the first state monitoring circuit and the second state monitoring circuit operate, the current command value is switched from the output value of the speed control loop to the external current command value, and the external current command value is the current The command value is reduced from the maximum value of the command value to a new external current command value in a predetermined decreasing pattern, and when the new external current command value is reached, the position command value of the position control loop is switched to zero; A switching / control circuit for setting the counter value of a deviation counter of
A servo controller comprising:

In a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
The position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop are input, and the change in the position detection value is zero and the position deviation exceeds a predetermined value. Further, in this state, a first state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value,
A speed detection value of the servo motor, a speed deviation of the speed control loop, and a current command value of the current control loop are inputted, and the speed detection value becomes zero and the speed deviation exceeds a predetermined value. A second state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in a state,
When one or both of the first state monitoring circuit and the second state monitoring circuit operate, the current command value is switched from the output value of the speed control loop to the external current command value, and the external current command value is the current A switching / control circuit that reduces the maximum command value to a new external current command value in a predetermined decreasing pattern, and switches the speed command value of the speed control loop to zero when the new external current command value is reached;
A servo controller comprising:

In a control circuit of a servo controller that controls a servo motor by a position control loop, a speed control loop, and a current control loop,
The position detection value of the servomotor, the position deviation of the position control loop, and the current command value of the current control loop are input, and the change in the position detection value is zero and the position deviation exceeds a predetermined value. Further, in this state, a first state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value,
A speed detection value of the servo motor, a speed deviation of the speed control loop, and a current command value of the current control loop are inputted, and the speed detection value becomes zero and the speed deviation exceeds a predetermined value. A second state monitoring circuit that outputs a state signal to the outside when a predetermined time has elapsed while the current command value remains at the maximum value in a state,
When one or both of the first state monitoring circuit and the second state monitoring circuit operate, the current command value is switched from the output value of the speed control loop to the external current command value, and the external current command value is the current A switching / control circuit for reducing the maximum external command value to a new external current command value in a predetermined decreasing pattern, and applying a brake added to the servomotor when the new external current command value is reached;
A servo controller comprising: