JPS5822592A - Speed controlling method for motor and device thereof - Google Patents

Abstract

PURPOSE:To enable to start the motor at the shortest time by a method wherein the integrated value of the integrated part obtained from the difference of speed in a steady state is recorded, and the integral value on record is used as an integral value when the proportional value is turned to zero due to the speed difference of the motor which is subsequently started. CONSTITUTION:A microcomputer circuit 6 reads the speed N of the motor 2 and compares it with command Nc when a command value Nc, a normal/reverse revolution command 16 and a starting command 17 are given, and calculates the error value (proportional value) in proportion to the difference of the above comparison. Also, an integral value is calculated based on the above error value, and a chopping duty signal 12 and a normal and reverse revolution signal 13 is given to a driving circuit 7 on the basis of the above calculation. When the motor 2 is started and the command value Nc and the motor speed N are equalized, the integral value is corrected so that the value of the integral part becomes the steady state value. Accordingly, the hunting, overshooting and undershotting can be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a motor speed control method and a speed control device thereof, which includes a command speed generator such as an encoder that measures the rotation of an operating shaft, and which drives the motor at a predetermined speed. The present invention relates to a motor speed control method and a speed control device for a motor equipped with a switching element.

Conventionally, in order to precisely control the speed of a DC motor, a proportional control method has been commonly used, in which a finger speed generator such as an encoder is attached to the motor or drive shaft, and the output is fed back to keep the speed constant. .

However, in this method, since the deviation component between the speed command value and the actual speed detected by a finger speed generator such as an encoder is fed back, it is impossible to reduce the deviation component to zero. An error occurred.

One way to solve this problem is to add integral control to feed back the amount obtained by integrating the deviation component to proportional control that provides feedback proportional to the deviation between the speed command value and motor speed. be.

On the other hand, as the load on the motor increases, the number of information devices increases, and the moment of inertia of the motor shaft or the load I/Lux to be subjected to the motor shaft becomes increasingly diverse.

In this case, with conventional equipment, the motor is directly connected to the equipment and the control loop gain, constant of the integral term, etc. are adjusted in each case to ensure that the speed is as smooth as possible without overshoot or undershoot at startup. I tried to stand up.

Also, if the power supply voltage that drives the motor changes, this is equivalent to a change in the gain of the control group, so the gain is adjusted each time. This was something that needed to be added.

In view of the above two points, the present invention has the following features in speed control:
Even if the load, inertia of the load, or voltage applied to the motor changes, it can be started at a constant speed in the shortest possible time, and there is no overshoot or vibration during startup.
It is an object of the present invention to provide a method for controlling the speed of a motor and a speed control device thereof.

The feature of the motor speed control method according to the present invention is that a motor equipped with a finger speed generator for speed measurement on the operating axis is driven at an arbitrary speed according to a speed command, and at least the speed command value and the motor speed are In a motor controlled by feedback, which includes a proportional term based on the difference between the speed command value and the motor speed, and an integral term obtained by time-integrating the difference between the speed command value and the motor speed, record the integral value of the integral term during steady state. Keep it
The present invention provides a motor speed control method in which the integral term is set to the recorded integral value when the proportional term becomes zero at the next startup.

Further, the feature of the motor speed control device according to the present invention is that it is composed of a motor having a finger speed generator for measuring the speed on the operating axis, and a control circuit that applies a variable voltage to the motor terminal. consists of a microcomputer that calculates and processes an arbitrary speed command and the speed from a circuit that detects the speed from the output of the finger speed generator, and a drive circuit that operates based on the output of this microcomputer. By recording the motor terminal voltage at speed, a microcomputer calculates the motor terminal voltage at steady speed based on the recorded voltage at the next startup, and controls the motor using this command. in the speed control device.

Next, before explaining embodiments of the present invention, for easy understanding, the basic technical idea of the present invention and
The invention will now be described in detail.

First, let's consider elements related to speed control.

First, there is (a) speed command value Nc.

This is the target value that controls the speed of the motor to a certain value.

Next, there is the motor speed N obtained from a finger speed generator such as an encoder that detects the speed of the motor shaft.

Furthermore, there is (c) a voltage component corresponding to the load torque and the back electromotive force of the motor, and this component is designated as Σke.

The output voltage Vout of the motor based on these is expressed by the following equation.

Vo,,t =01 (Nc N)+Σk e
-----...-fl) The first term on the right side of equation (1) is called the proportional term, and if the difference between speed N and speed command value (hereinafter referred to as command value) Nc is large, That is, when accelerating,
Motor output voltage V. 1, which is the dominant value in t, becomes zero when the speed N becomes equal to the command value Nc. Note that G1 is a constant for this term, which is determined by the gain and the like.

Therefore, at startup, the above term becomes a dominant large value and accelerates the motor.

The second term on the right-hand side above is equivalent to the previous value, including when performing digital control of the voltage component corresponding to the load torque and back electromotive force of the motor. Assuming that Σken-1, the current Σken is given by the following equation.

Σk e n−Σk e n−1+K d −
--(2) Here, K d is a value related (proportional) to (NC-N) (an integrand value regarding an integral term).

In such control, the first term on the right side of equation (1) functions to generate acceleration torque, and becomes zero in a steady state.

Further, as described above, the second term is a term corresponding to the load torque and the back electromotive force of the motor, and is integrated during acceleration, and has a certain value Σke1 in a steady state.

From this result, if the value of Σke is equal to the steady-state value Σke1 at the end of acceleration, the speed becomes stable immediately.

In addition, the power generation constant of the DC motor is 1 (n (V/ rpm
), the steady state speed of the motor is Nlrpm (motor steady speed), the armature resistance of the motor is R (Ω), the load torque is Tt (Kq-m), and the torque constant is K t (K
q·m/A), the voltage yt required to maintain the current in a steady state is given by the following equation.

V t =Kn −N□+ (R, xTt) /K t
−・−・−(31 Now, for simplicity, let Kd, which changes in proportion to (NC-N), be a constant value Kdl, that is, let Kd=Kdl in equation (2), and let the acceleration time be tl. Then, the integral term in equation (1) is expressed by the following equation at the end of acceleration.

Σke=J(dlX't -=... be.

Kn-N, + (T'(, XTt) /, t=Kd
l X t, ・(51If the acceleration is α1, it becomes as follows.

Kn −N+ (R, XTl)/Kt = Kd I X
(N/α+) ・(6) From this equation (6), Kdl
The following equation is obtained.

Kd 1 ==(ffil(r<n+ (n,+'rz
) /N−Kt )−・−・−・−(7) In other words, going back to the beginning, Kdl regarding the integral term Σke in equation (1) mentioned earlier is, as in equation (7) above, ( 9) -m- It is determined if the acceleration α1 and the load l and the torque Tt are known.

This corresponds to the load, and the load inertia is measured at the acceleration α1,
By calculating Kdl commensurate with this, changes in load inertia can be accommodated.

In general, permanent magnet motors are mainstream as motors for information devices, and the load has a large inertial load, and the load torque Tl is small compared to the inertial load. In such a case, in the steady state, the term contributing to the back electromotive force, that is, the previous (6)
It is only necessary to consider the first term on the left side of the equation, and by combining equation (7),
Kdl is expressed as follows.

Kdl-α1・Kn ・・・・・・・・・(8) From the above, the simplest way to incorporate load response into speed control is to measure the acceleration α, as in equation (8) above. Therefore, if Kd related to the integral term in equation (1) is corrected and started, stable startup will be completed in the shortest possible time, and the value Σke of the integral term at this time will be approximately equal to the value corresponding to the back electromotive force in the steady state. The motor speed N, which is equal to Σke1, immediately becomes the steady speed N1.

(10) This situation will be explained with reference to FIG. In other words, Fig. 1 is a starting characteristic diagram, and the broken line in the figure is K related to the integral term.
The solid line shows the case where d is not corrected, and the solid line shows the case where d is corrected.

In the example shown in FIG. 1, the motor speed rises quickly due to a decrease in load inertia or an increase in power supply voltage.

That is, in the case of the broken line shown in the figure where Kd is not corrected, the motor speed N approaches the steady value and the proportional term at (N
Even if lN) becomes smaller, the value of the integral term Σke does not reach the steady value Σke1, so the motor speed N also does not reach the steady value, and the motor speed is not stabilized until time t2 when the integral term reaches the steady value.

On the other hand, in the method of correcting Kd related to the integral term shown by the solid line, if the motor speed N reaches Nsl within a certain time t81, the acceleration α1 becomes NS, /ls
, and if the time ts1 is chosen small enough, the value T((1
is corrected to Kdl, and the slope of Σke is made like the solid line.

(11) When N, Σk e also reaches the steady value Σk c 1,
Since the proportional term G, (Nl-N) becomes zero, the speed of the motor smoothly shifts to a steady state.

Therefore, the starting time of the motor can be significantly shortened at t, compared to t2 indicated by the broken line.

Next, FIG. 2 is a start-up characteristic diagram as well, and is an example in which the start-up time becomes longer due to an increase in the inertia of the load or a decrease in the power supply voltage.

That is, in the curve shown by the broken line in which K d related to the integral term is not corrected, the integral term Σke related to the voltage when the motor speed N reaches the steady value N1 is equal to the steady value Σkel
Become bigger.

In this case, the motor speed N becomes larger than the steady-state value N, reaching over 7 feet, and the integral term starts to decrease, but at the point where the speed N crosses the steady-state value N1, the value of the integral term,
When Σke becomes lower than the steady value Σke 1, undershoot occurs, but this decreases and settles down to the steady value at time t2.

For this, K d regarding the integral term is corrected (12
), as shown by the solid line, a certain time t after startup.
Since the acceleration α can be detected by measuring the change Ns1 in the motor speed N during the time ts,
Then, by correcting the integral term Kd to Kdl accordingly, the value Σke of the integral term at time t when the motor speed N reaches the steady value N becomes the steady value Σke1, so the motor's The speed settles down to a steady value N.

In this way, at startup, the acceleration α1 is detected and the integral term Σ
By correcting ke, vibration at startup can be suppressed and startup time can be shortened.

As methods for measuring acceleration in the above, there are two methods: a method of measuring changes in speed per unit time, and a method of detecting time at a unit speed.

FIG. 3 is an acceleration detection characteristic diagram showing a method of measuring speed changes in unit time.

That is, when the velocity Ns per unit time ts1 is measured, the acceleration α1 is obtained by the following equation.

α to N sl / t J ・・・・・・・・・
・(9) Figure 4 is an acceleration detection characteristic diagram showing the (1.3)-c, 1 method of detecting time at unit speed.

That is, when the time tS2 to reach the unit speed NS2 is measured, the acceleration α1 is obtained by the following equation.

α is Ns□/l, ・・・・・・・・・QO) Using the acceleration α obtained above, calculate and correct K d regarding the integral term using the equation (8) above. For example, even if the load inertia changes, it can be adequately coped with.

Furthermore, the following method is available as a method for shortening the startup time without performing correction calculations every time the system is started.

In this method, the correction calculation of the integral term Σke is performed and started at the very beginning when the power is turned on, as explained in FIG. 1.2.

Integral terms Σk e l and K d after time t1 when speed command value Nc and motor speed N become approximately equal are recorded. When the motor stops once and starts again, it is not necessary to measure the acceleration for correcting the integral term Σke explained in Figures 1 and 2, and the K d used for the -th start is is used to integrate the integral term Σke until the completion of startup.

When the start-up is completed, the current integral term Σke is compared with the value recorded the first time, and the K dO value is corrected and recorded based on the difference, and is used for the next start-up.

That is, if the current integrated value is larger than the initially recorded Σke, the value of Kd is too large, so the value of Kd is lowered and recorded.

In this way, as the number of activations increases, ideally the activation can be performed in the shortest possible time.

In a device that operates steadily, the first startup when the power is turned on changes the speed command value Nc to the steady value N and a smaller value N. Start it up in a short time and record the K d at that time.

This value of K d can be used for starting the steady speed N1 from the second time onwards.

This operation will be explained with reference to FIG. 5, which is a starting characteristic diagram.

Note that (a) is the -th time, and (b) is the second time.

Assuming that the steady speed is N1, the first time when the power is turned on is the steady speed N, and a speed N that is sufficiently lower than the steady speed N1. Activate the command.

(15) In this case as well, as shown in FIGS. 1 and 2, the acceleration α.

is detected, Kd is corrected, activated, and J(d is recorded.

Next, in the case of the second and subsequent steady startups, the integral term Σke is determined using the previous recorded start point Kd.

Generally, a motor drive circuit uses a current limiter or the like in consideration of the current capacity of the semiconductor, so the startup is almost constant torque startup.

However, since the rise of the motor speed N is almost linear, if we use K d recorded at the time of initial startup as is to find the integral term Σke, we can calculate the time t for completion of startup.
, then exactly Σ1(el).

Next, if you record the integral term Σke1 when the first startup is completed in Figures 1 and 2, the difference between the speed command value Nc and the speed N will become zero without integrating by Kd. Maximize the output voltage v, ut until (NC-
By recording Va ++ t in advance and setting it to Σ1(el) at the moment when N) becomes zero, the motor can be started in the shortest possible time.

(16) FIG. 6 is another starting characteristic diagram showing the second and subsequent starting.

Output at startup ■. , is not the value shown in Equation (1) above, but gives the maximum voltage v0° until (Nc N) becomes zero, and the difference between the speed command value Nc and the speed N becomes zero. Check.

If (Nc N) becomes zero, it means that startup is complete, so with Vout□ set to zero, the output voltage V. Let t be Σ1(el) obtained at the first startup. After startup, the output voltage Vout is set as shown in equation (1).

When this method is used as the integral term ΣkeQ (the final value of the integral term of provisional activation) when the first time is started at a low speed No. shown in FIG. 5, Σke of the following equation is used.

Σk e−Σk e OX (N+ /No)
・"=..."(II) As detailed above,
The device according to the present invention has the characteristics described above.

Next, an example of the motor speed control method of the present invention will be described.
(17) An embodiment of the speed control device will be described with reference to each figure.

Here, FIG. 7 is a configuration diagram of a speed control device according to an embodiment of the present invention, FIG. 8 is a configuration diagram of its speed detection circuit, and FIG. 9 is an operation explanatory diagram of the speed detection circuit. Figure 10 shows
The drive circuit diagram, FIG. 11 is an explanatory diagram of the operation of the drive circuit, FIG. 12 is an operation block diagram of the microcomputer, and FIG. 13 is a flowchart of a speed control method according to an embodiment of the present invention. 1 and 14 are flowcharts of a speed control method according to another embodiment.

First, in FIG. 7, 1 is a power supply, 2 is a motor, 3 is a load inertia and a load, 4 is an encoder related to a finger speed generator, a 5-digit speed detection circuit, 6 is a microcomputer, and 7 is a drive circuit. It is.

Still, 10 is the rotation signal which is the output of encoder 4, 1
1 is a speed signal (signal related to motor speed N) which is the output of the speed detection circuit 5, 12 is a duty signal, 13 is a forward/reverse signal, ]4 is a forward rotation output collar 15 is a reverse rotation output, 16. 17 is a start command, and Nc is a command value related to a speed command as described above.

Further, 20 to 23 are transistors, and 24 to 27 are diodes.

That is, a 1-1 type bridge circuit including transistors 20 to 23 and a bridge circuit including diodes 24 to 27 are connected to the power source 1.

In addition, the collector of the transistor 20゜22 and the cathode of the diode 24.26 are connected to the positive side of the power supply, and the emitter of the transistor 21.23 and the anode of the diode 25゜27 are connected to the negative side of the power supply. There is.

The emitter of the above transistor 20 is the transistor 2
1 collector and the anode of diode 24,
Together with the cathode 50, it is connected to one terminal of the motor 2, and the other terminals of the motor 2 are connected to the emitter of the transistor 22, the collector of the transistor 23, the anode of the diode 26, and the cathode of the diode 27.

Therefore, the shaft of the motor 2 is connected to the load 3 and the engine (19). The rotation signal 10 is input to the speed detection circuit 5.

Speed signal 11 (N) which is the output of the speed detection circuit 5 mentioned above
is input to the microcomputer circuit 6.

Furthermore, a command value Nc, a forward/reverse command 16° start command 17 are input to the microcomputer circuit 6 from an external device.

The microcomputer circuit 6 outputs a duty signal 12 that determines the duty when the transistors 20 to 23 are subjected to chopping control, and a forward/reverse signal 13 that generates forward rotation torque and reverse rotation torque in the motor 2, and the drive circuit 7 is entered.

The normal rotation output 14 which is the output of the drive circuit 7 described above is l
・Base 2 and reverse output 15 of transistor 20.23 are:
They are connected to the bases of transistors 21 and 22, respectively.

The operations related to the above configuration are as follows (20) be.

The microcomputer circuit 6 receives a command value Nc and a forward/reverse command 16. When the start command 17 is given, the speed N of the motor 2 is taken in from the speed detection circuit 5, compared with the command value Nc, and an error value (the proportional term mentioned earlier) is calculated according to the difference.

Still, the above integral term is calculated using the error value, and based on these, the voltage to be applied to the motor 2 is determined, and the duty signal 12 is output as the chopping duty, and the rotation direction of the motor 2 is determined. It is determined and the forward/reverse rotation signal 13 is output.

As a result, the drive circuit 7 operates, and in the case of forward rotation, turns on the transistors 20 and 23 in accordance with the duty signal 12, causing the motor 2 to rotate.

At the beginning of the startup, the motor speed N is low, so the command value N
Since the difference with c is large and the value of the integral term Σke is also sufficiently small, the duty signal 12 that turns on the motor 2 is determined by the equation (G in equation 11; (N c - N )) and becomes a large duty signal. to accelerate motor 2.

(21) When the motor 2 approaches the command value Nc, Gz (Nc N
) becomes small, the integral term Σke increases, and at the time when starting is completed, the command value Nc and the motor speed N become equal.

Exactly at this point, the value Σke of the integral term becomes the steady value Σke1
Since the integral term is corrected so that the motor 2 smoothly reaches the steady speed N1.

Next, each of the above blocks will be explained in more detail.

An example of the speed detection circuit 5 includes a counter 5J and a latch 52 as shown in FIG.

In the figure, a rotation signal 1o from the encoder 4 is input to a clock input of a counter 51, an enable signal 53 for a certain period of time is input to an enable terminal of the counter 51, and a reset signal 54 is input to a reset terminal.

The outputs SO to Sn of the counter 51 are input to the latch 52, and the output of the latch 52 is taken out as a speed signal 11 related to the motor speed N to the microcombi (22).

A strobe signal 55 is input to the latch 52 .

In this operation, as shown in the time chart of FIG. 9, the counter 51 performs an opening operation when the enable signal 53 is received, and outputs the rotation signal 10 to the outputs SO to Sn.

Next, the strobe signal 55 of the latch 52 causes the output 5 to
The content of the signal related to o-sn is latched by the latch 52, and at the next moment, the counter 51 is reset by the reset signal 54 to prepare for the next count.

Therefore, the rotation signal 10 during the enable signal 53 for a certain fixed period of time is also counted, and a value proportional to the motor speed is obtained as the speed signal N.

Next, the drive circuit 7 is composed of an inverter gate 71 and AND gates 72 and 73, as shown in FIG.

The duty signal 12 is connected to the negative power of the AND gates 72 and 73 (23), and the forward/reverse signal 13 is connected to the power of the AND gate 72, and the inverter power is connected to the power of the AND gate 73.
The same forward/reverse signal 13 is connected through the terminals 1 and 71.

With this configuration, as shown in FIG. 11, the output of the AND gate 72 is such that the forward/reverse signal 13 is
Duty signal 12 appears only at level, and normal rotation output J
It becomes 4. Further, the output of the AND gate 73 becomes the reverse rotation output 15 because the duty signal 12 appears only when the forward/reverse rotation signal 13 is at the "'0" level.

Therefore, the microcomputer 6 mentioned earlier has a central processing unit, R, A, M (Random Access Memo January).

It consists of R, OM (read only memory), input/output, etc., and operates according to a program recorded in ROM.

FIG. 12 shows its operational blocks.

After receiving the command value Nc, start command 17, and forward/reverse command 16 from an external device, read the motor speed N and compare the speeds. From the difference between the command value Nc and the motor (24) speed N, the previous (1) Calculate the proportional term Gl (Nc N), which is the first term on the right side of the equation, calculate the acceleration from the velocity at a certain time, calculate the integral term, calculate the duty, and determine the forward/reverse direction. , and outputs a duty signal 12 and a forward/reverse signal 13.

2, an example of the operation of the present invention will first be described with reference to the flowchart of FIG.

First, when the power is turned on, the flowchart starts.

First, the unit time ts1 related to the reference time for measuring acceleration α1 and K d related to the integral term of equation (1) above.
Set the value of

The command value Nc, motor speed, speed N, l(,w) related to the appropriate reversal command are read, a sufficiently small Nc2 is set for the speed command Nc, and the proportional term of the equation (]) is calculated.

Then, it is checked whether the difference between the speed setting value Nc2 of the temporary start and the motor speed N is zero, that is, whether the motor speed N has reached the speed Nc2, and (25) it is determined that the speed Nc2 has not been reached. For example, check whether the time since the start of startup is equal to the value ts1 set at the beginning,
If they are equal, the motor speed Ns at this time.

Divide the acceleration α from and correct Kd.

If the time from the start of activation is outside the set value, calculation of acceleration α1 and correction of Kd are not performed.

Next, Σk e is calculated as shown in equation (2) above to obtain the value of the integral term, and this value is stored in memory and used for the next repeated calculation.

Based on these results, the chopping duty Dt is calculated, the signal RO related to the motor rotation direction is determined, the duty signal 12 and the forward/reverse rotation signal 13 are output, and the process returns to input reading.

After repeating this process, if the motor speed N reaches the speed setting value Nc2, Kd and the value of the integral term Σke
Q is memorized, the chopping duty Dt is set to zero, and the motor is stopped.

When the motor stops, the process moves to the block shown within the dotted line of A in FIG. 13.

(96) Here, it is checked whether the start command 17 in Fig. 7 is input, and when the start command 17 is input, the speed command value Nc, the speed N, and the forward/reverse command RW are taken in, and the equation (1) above is Calculate the proportional term.

Then, it is checked whether the difference between the speed command value Nc and the motor speed N is zero, that is, whether the motor speed N has reached the steady speed N1. and store the new Σke.

Next, the chopping duty signal 12 and the forward/reverse rotation signal 13 are calculated and output, and the start command 17 is checked.

If there is a trench containing the signal related to start command 17, the above-described operation is repeated to continue the activation.

The startup is completed when the speed N reaches the steady value N1, so (
1) Calculate the equation, calculate and output the chopping duty signal 12 and forward/reverse rotation signal 13, and proceed to check the signal related to the original start command 17.

If the signal related to the start command 17 is off, (27) stop. The next time you start it up, do the same thing as above.

Next, although the first startup when the power is turned on is the same as that shown in FIG. This will be explained using the flowchart shown in the figure.

Check whether the signal related to the start command 17 is on or off, and if the same signal is received, read the speed command value Nc, motor speed N, and forward/reverse command 1%w, and the motor speed N becomes the speed command value Nc.
Check whether it has been reached.

This is equivalent to checking whether the motor has completed starting.

If the motor speed N has not reached the speed command value Nc, the chopping duty Dt is set to the maximum value, and a forward/reverse signal 1%o is determined and output.

Next, returning to the beginning, the signal related to the start command 17 is checked. If the same signal is received, the above operation is repeated and the motor speed N increases.

Motor speed N becomes equal to speed command value Nc (28) When the startup is completed, calculation of equation (1) is performed.

In the calculation of equation (1), for the integral term, Σke, which is a value obtained by multiplying Σke Q recorded when the power was turned on by Nc /Nc2, is used.

Next, the duty Dt is calculated and output, and the process returns to checking the original start command 17 signal.

If the signal is turned off, the duty Dt is set to zero and output, thereby stopping the motor.

As described above, according to the present invention according to the above-mentioned embodiments, by performing temporary startup once when the power is turned on, startup can be performed in the shortest possible time during steady state startup, and furthermore, it is possible to start up in the shortest possible time during steady state startup. Therefore, it is possible to obtain a speed control method and a speed control device that eliminate overshoot and undershoot during startup and enable startup in the shortest possible time.

Taking all of the above into account, the present invention can prevent knocking and overshoot during startup due to changes in load inertia or changes in motor drive power.
This invention eliminates undershoots and can be expected to start up in the shortest possible time, and can be said to be an invention with excellent practical effects.

[Brief explanation of the drawing]

Fig. 1.2 is a starting characteristic diagram, Fig. 3.4 is an acceleration detection characteristic diagram according to an embodiment of the present invention, and Figs. 5 and 6 are a starting characteristic diagram according to each embodiment of the present invention. FIG. 7 is a configuration diagram of a speed control device according to an embodiment of the present invention, FIG. 8 is a configuration diagram of its speed detection circuit, FIG. 9 is an explanatory diagram of the operation of the speed detection circuit, and FIG. , its drive circuit diagram, Figure 11, is:
FIG. 12 is an operational block diagram of the microcomputer, and FIGS. 13 and 14 are flowcharts of the speed control method according to each embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Power supply, 2... Motor, 3... Load inertia and load, 4... Encoder, 5... Speed detection circuit,
6...Microcomputer, 7...Drive circuit, 20-23...Transistor, 24-27...Diode, Nc...Speed command value, Nc2...Temporary startup speed setting value, N ...Motor speed, N1...Motor steady speed, G...Constant determined by gain, etc., α1.
...Acceleration, Σk e...Value of integral term, Σ1(eO・
...Final value of the integral term at temporary start, Σke1...Value of the integral term at steady motor speed, Kd...Integrand value regarding the integral term, Dt...Duty of chopping, RIWI
RIO...Forward/reverse signal. Agent Patent attorney Kosaku Fukuda (and 1 other person) (31) No. 10 No. 2 Prisoner No. 3 No. 40' is2 Moro No. S Oral funeral Otsu-ku No. 8 z Yq Mouth 53 % S? L

Claims (1)

[Claims] 1. A motor equipped with a finger speed generator for speed measurement on its operating axis is driven at an arbitrary speed by a speed command, and at least a proportional term due to the difference between the speed command value and the motor speed is , in which the motor is controlled by feedback of an integral term that is the time-integrated difference between the speed command value and the motor speed, the integral value of the integral term at a steady speed is recorded, and the following A method for controlling the speed of a motor, characterized in that when the proportional term becomes zero at startup, the integral term is set to the recorded integral value. 2. In the product described in claim 1, the acceleration is measured at the next startup, and the startup time is calculated based on this, so that the integral term becomes equal to the recorded value at this startup time. A method for controlling the speed of a motor. 3. In the item described in claim 1, the speed feedback is performed until the motor speed becomes equal to the speed command value.The motor is accelerated to the maximum, and the speed feedback is enabled until the motor speed becomes equal to the speed command value, and , a motor speed control method in which the integral term is set to the recorded value. 4. In the device described in claim 1, when the power is turned on, a speed command sufficiently lower than the steady speed is given to temporarily start, and the integral term at the time of completion of the start is recorded, and the steady speed is determined. A method for controlling the speed of a motor, which calculates the value of an integral term at a steady speed based on the recorded integral value upon completion of starting the motor, and uses this value as the value of the integral term. 5. It consists of a motor that has a finger speed generator on its operating axis to measure the speed, and a control circuit that applies a variable voltage to the motor terminal, and the control circuit can receive any speed command and the finger speed generator. It consists of a microcomputer that calculates and processes the speed from the speed detection circuit from the output of the motor, and a drive circuit that operates based on the output of this microcomputer, and records the motor terminal voltage at steady speed. A speed control device for a motor, characterized in that the motor terminal voltage at a steady speed is calculated by a microcomputer based on the recorded voltage at the next startup, and the motor is controlled using this command.