KR0158087B1 - Driving apparatus for a commutatorless dc motor - Google Patents

Abstract

The spike voltage g is generated when the energization phase is changed by rectification for the purpose of accurately recognizing the counter electromotive voltage signal without affecting the spike voltage and improving the stable operation. The counter voltage signal h, which represents the zero cross point of the counter voltage, is generated from rectification to the next rectification, which is later than the spike voltage g. Therefore, the last one of the signals given between the occurrence of the current rectification (t ₁ ) to the next occurrence of the rectification (t ₂ ) is recognized as a valid counter electromotive voltage signal, and the influence of the spike voltage (g) is eliminated. do.

Description

Driving device of DC motor without commutator

1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a waveform diagram showing a counter electromotive voltage signal and a rectification control signal in the configuration of FIG.

3 is an explanatory diagram for explaining the determination of the commutation cycle.

4 is a flowchart of a control device of the configuration of FIG.

FIG. 5 is a flowchart of the control device of FIG. 1, and is connected to FIG.

* Explanation of symbols for main parts of the drawings

1-3: drive coil, 4-9: switching transistor

11 control device 12-14 comparator

15, 17: resistance

The present invention relates to a drive device for a DC motor without a commutator. In the drive device which detects the rotor position by using the counter voltage generated in the drive coil of the DC motor without a commutator and controls the rectification of the drive current to the drive coil, the spike voltage generated in the drive coil in the case of rectification is Adversely affect the rotor position detection.

In the rotor position detection circuit of a commutator-less motor described in Japanese Patent Application Laid-Open No. 58-25038, an integral circuit with a spike voltage superimposed with a spike voltage is integrated in an integrating circuit, the integrated output is compared with a zero potential, and a logic circuit is interposed. To generate a rectification control signal.

According to the above-described prior art, since the spike voltage is also integrated with the counter electromotive force signal, an error occurs at the zero cross position of the counter electromotive force signal, which causes a problem in that the safe operation of the motor does not occur due to the incorrect position detection. .

The present invention has been made on the basis of the above-described aspect, and an object thereof is to provide a drive device for a commutator-free DC motor capable of accurate position detection and improved safety driving without being influenced by a spike voltage.

In the present invention, a counter electromotive voltage signal generating means for applying a counter electromotive voltage signal, which represents a zero cross point of a pulse-formed counter electromotive voltage by comparing a counter electromotive voltage generated in a drive coil of a DC motor without a commutator with a neutral point potential of the drive coil, is provided. In the drive device of a rectifier-free DC motor for rectifying control of the drive coils by controlling the switching element in accordance with the counter electromotive voltage signal, a counter electromotive force signal applied from the occurrence of the current rectification to the occurrence of the next rectification. In the output of the generating means, by means of a driving device of a commutator-free DC motor having a recognizing means for recognizing the last given as a valid counter electromotive voltage signal, and for rectifying control of the drive coil in accordance with the recognized effective counter electromotive voltage signal, To achieve the above object.

Further, in the present invention, the counter electromotive voltage for imparting a counter electromotive voltage signal, which represents a zero cross point of the counter electromotive voltage, pulse-formed by comparing the counter electromotive voltage generated in the drive coil of the DC motor without a commutator with the neutral point potential of the drive coil. A drive device for a rectifier-free DC motor which has a signal generating means and performs rectification control of a driving coil by controlling a switching element in accordance with a counter electromotive voltage signal, which is provided from the occurrence of the current rectification to the occurrence of the next rectification. The actual zero cross time for recognizing the last given end of the output of the counter electromotive voltage signal generating means as a valid counter electromotive voltage signal and giving the time from the generation of the current rectification to the generation of the effective counter electromotive voltage signal as the actual zero cross time. The detection means and the counter electromotive force signal effective in the generation of this rectification are negative. A target zero cross time setting means for setting a target zero cross time to be set in accordance with the current rectifying cycle, and a difference between the target zero cross time and the actual zero cross time so that an effective counter voltage signal is generated at the target zero cross time. The rectifier cycle determining means for determining the next rectification cycle by the proportionality and integration according to the difference described above, and by the drive device of the commutator-free DC motor to control the rectification of the drive coil in accordance with the determined rectification cycle, Achieve the purpose. In the above configuration, when the actual zero cross time detecting means cannot give the output of the counter electromotive force signal generating means from the occurrence of the current rectification to the occurrence of the next rectification, the current rectification period is actually zero crossed. It can be configured to give as time.

Further, the target zero croch time setting means sets the target zero cross time in a time width up to the j th time that divides the current rectification cycle by k equals, and the rectifying cycle determining means

Formula

Where Tin is the integral of the next commutation cycle, Ki is the integral tn- ₁ is the difference between target zero cross time and actual zero cross time, Tin- ₁ is the integral value of the current rectification cycle, Tn is the next rectification cycle, and Kp is the proportional constant. can do.

The spike voltage occurs when the energized phase changes due to rectification.

The counter electromotive force signal, which represents the zero cross point of the counter electromotive voltage, is generated from the rectification to the next rectification and is later than the spike voltage. Therefore, the last one of the counter electromotive force signal generating means provided during the generation of the current rectification to the next generation of rectification is recognized as the effective counter electromotive voltage signal, so that the counter electromotive force signal can be accurately recognized without being affected by the spike voltage. .

According to the invention of claim 2, in accordance with the proportional and integral operation according to the difference between the target zero cross time at which the valid counter voltage signal is to be applied and the actual zero cross time at which the valid counter voltage signal is actually applied, the target zero cross time The commutation period is adjusted to generate a valid counter voltage signal.

EXAMPLE

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a counter electromotive voltage signal Z _A , Z _B , Z _C and a rectification control signal A _U , A _L , B _{U in the} configuration of FIG. 1. , B _L , C _U , and C _L ).

In Fig. 1, (1, 2, 3) denotes a commutator for controlling the rectification of the drive coils 1 to 3 of the drive coils 4, 5, 6, 7, 8, and 9 of the DC motor without a commutator. It is a switching transistor. In the switching transistors 4 to 9, the power supply 10 is applied to the collector and the emitter circuit, and the rectification control signals A _U to C _L are applied to the base from the control device 11. . The switching transistors 4 to 9 are turned on and off in accordance with the rectification control signals A _U and C _L , whereby driving currents to the driving coils 1 to 3 are rectified and are not shown. The permanent magnet rotor is rotated.

In the state of rotation, the counter electromotive voltage is applied in the drive coils 1-3.

(12, 13, 14) are comparators, and the comparators 12-14 are resistors constituting the counter voltage from the drive coils 1-3 and the virtual neutral point of the drive coils 1-3. 16 and 17, the neutral point potential and the like are input to give the control device 11 pulse-shaped counter electromotive force signals Z _A to Z _C. The counter electromotive voltage signals Z _A to Z _C represent zero cross points of the counter electromotive voltage at which the rising section and the falling section are induced in the driving coils 1 to 3. The spike voltages generated in the case of rectification are superimposed on the counter electromotive voltage induced in the drive coils 1 to 3, and the spike voltages a and b are shown in the counter electromotive voltage signals Z _A to Z _C as shown in FIG. , c, d, e, f) will appear. The spike voltage (a) is generated by switching from the states of A _U = 1 and B _L = 1 to the states of B _L = 2 and C _U = 1. The same is true for other spike voltages.

The control apparatus 11 has the following function. The control device 11 is the last of the rising section or falling section of the counter electromotive voltage signal Z _A to Z _C applied from the comparators 12 to 14 during the current rectification to the next generation of the rectification. The rising section of the effective counter voltage signal (Z _A to Z _C ) is recognized from the occurrence of current rectification by recognizing that given to the rising or falling section of the effective counter voltage signal (Z _A to Z _C ). The time until the partial or falling section is detected as the actual zero cross time (t _act ). The controller 11 is provided with the rising section or the falling section of the counter electromotive voltage signals Z _A to Z _C from the comparators 12 to 14 between the generation of the current rectification and the generation of the next rectification. If not, the current rectification period is detected as the actual zero cross time t _act . This occurs when the rectifying timing is an introduction phase of 30 degrees or more with respect to the counter electromotive voltage signals Z _A to Z _C.

The controller 11 sets a target zero cross time t _act indicating a target time so as to give a rising section portion or a falling section portion of the counter electromotive force signal effective from the occurrence of the current rectification.

Here, (j / k) · T _n-1 is set according to the time width up to the jth obtained by k equalizing the current rectification period T _n-1 . The target zero cross time t _act is normally set to be the center of the commutation period as j = ₁ , k = ₂ . To change the values of j and k, you can change them arbitrarily. The controller 11 is a difference between the target zero cross time t _ref and the actual zero cross time t _act . t _n-1 = t _ref -t _act to integrate the integral of the next commutation period (T _in ),

Where k ₁ is the integral constant and T _in-1 is the integral value of the rectification cycle. The controller 11 is a car ( t _n-1 ) and the next rectification period (T _n ) according to the integral value (T _in ) of the next rectifier,

Here, K _p is a proportional integer, and thus determined by proportional operation. The control apparatus 11 includes a reverse voltage signal (Z _A ~ Z _C) commutation control signal (A _U ~ C _L) for distribution, and distribution of the rectified control signal ((A _U ~ C _L) depending on the state of Is output to the switching transistors 4 to 9 at the next rectification timing.

3 is an explanatory diagram for explaining the determination of the commutation period. In the figure, g is a spike voltage and h is a valid counter voltage signal. In generating time point (t ₁₎ of the rectifier of a current time from the signal (g) and (h) it is given between the following occurs: the point of meeting the rectifier (t _2), the signal (h) that occurred last is recognized as a valid counter voltage signal .

Generating time point Inverse total pressure (h) available from (t ₁₎ of the rectification of the current time is the detection of the actual zero-cross time (t _act) to be actually given. Based on the current rectification period T _n-1 , a target zero cross time t _ref , which is a target time to which a valid counter electromotive voltage signal h is to be given, is set. The difference between the target zero cross time (t _ref ) and the actual zero cross time (t _act ) t _n-1 ) is computed so that the effective counter electromotive voltage signal h is given to the target zero cross time t _ref . t _n-1 ) determines the next settling time (t _n ) from common sense.

The rectification control signals A _U to C _L are respectively distributed in accordance with the states 1 to 6 of the counter electromotive voltage signals Z _A to Z _C. In the state (1) of the counter electromotive voltage signal (Z _A to Z _C ), that is, Z _A to Z _C = (0, 0, 1), the rectifier control signal A _U = 0, B _L = 0, C _U = 1, A _L = 1, B _U = 0, C _L = 0 is distributed, and in the state (2) of Z _A to Z _C = (0, 1, 0), the rectifier control signal A _U = 0, B _L = 0, C _U = 0, A _L = 0, B _U = 1, C _L = 1 is distributed, and in the state (3) of Z _A to Z _C = (0, 1, 1), the commutation control signal A _U = 0, B _L = 0, C _U = 0, A _L = 1, B _U = 1, C _L = 0 are distributed, and in the state (4) of Z _A to Z _C = (1, 0, 0), rectification control signal A _U = 1, B _L = 1, C _U = 0, A _L = 0, B _U = 0, C _L = 0 were distributed, and in the state (5) of Z _A to Z _C = (1, 0, 1) Rectification control signal A _U = 0, B _L = 1, C _U = 1, A _L = 0, B _U = 0, C _L = 0 are divided, and Z _A ~ Z _C = (1, 1, 0) In state (6), rectification control signals A _U = 1, B _L = 0, C _U = 0, A _L = 0, B _U = 0, and C _L = 1 are distributed.

The distributed rectification control signals A _U to C _L are applied to the switching transistors 4 to 9 so that rectification is generated.

4 and 5 are flow charts of the control device 11 of the configuration of FIG. 1, and the terminals A and B in FIG. 5 are connected to the terminals having the same reference numerals in FIG. The operation of the above configuration will be described below using FIG. 4 and FIG. 5 together.

The DC motor without commutator is started by synchronous operation, accelerated to a state in which the counter electromotive voltage is stably output, and then switched to the operation according to the above configuration. In the beginning of switching, the control apparatus 11 sets a constant rectification period in step 30, and switches the predetermined rectification control signals A _U to C _L in the next step 31 to the switching transistors 4 to 9. ), And the operation based on the counter electromotive voltage signals Z _A to Z _C is started.

The control apparatus 11 sets next commutation timing from the commutation period in step 32, resets and starts the internal timer in step 33 to start the measurement of the actual zero cross time t _act , and the step At 34, a flag for indicating the occurrence of a counter electromotive voltage signal is returned. Accordingly, step 35 is entered to determine whether the rising section or the falling section of the counter electromotive voltage signals Z _A to Z _C has occurred. If a spike voltage is generated, the spike voltage g shown in FIG. 3 is first detected, and the flow goes from step 35 to step 36, the internal timer recognizes the detection time, and the actual zero cross time t _act ).

The internal timer continues the time count as it is. In a next step 37, a flag indicating whether or not a counter electromotive voltage signal is generated is set, and then in step 38 it is determined whether or not a rectification timing is present. If it is not the rectifying timing, the flow returns to step 35 from step 38. If the rising section portion or the falling section portion of the counter electromotive voltage signals Z _A to Z _C is not generated in step 35, the flow immediately enters step 38 in step 35. If a valid counter electromotive voltage signal h is generated after the spike voltage g, the flow goes from step 35 to step 36 where the internal timer recognizes the detection time and the actual zero cross time previously stored t _act. Instead, remember this as the actual zero cross time (t _act ). Since the effective counter voltage signal h occurs after the spike voltage g, the actual remaining zero cross time t _act is the time from the occurrence of rectification until the valid counter voltage signal h is given. Will be displayed.

Control device 11 is recognized, into rectification control signal (A _U ~ C _L) depending on the state of the current reverse voltage signal (Z _A ~ Z _C) in step 39 that the commutation timing in step 38 Is distributed to the switching transistors 4-9. This results in new rectification. In step 39 of step 39, it is determined whether or not a flag indicating whether or not a counter electromotive force signal is generated is set. If the flag indicating whether or not the counter electromotive force signal is generated is not set, the current rectification period is stored as the actual zero cross time t _{act in} step 41, and then the next time in steps 42 and 43 is performed. Advance to the determination of the commutation cycle. This occurs when the rectifying timing is an introduction phase of 30 ° or more with respect to the counter electromotive voltage signals Z _A to Z _C.

If a flag indicating whether or not a counter electromotive force signal is generated is set, step 42 immediately enters steps 42 and 43. The controller 11 sets the target zero cross time t _ref in step 42, and the difference between the target zero cross time t _ref and the actual zero cross time t _{act in} next step 43. ( based on t _n-1) to obtain the following integral difference (T _in) of the conference commutation period in accordance with the integral calculation tea ( t _n-1 ) and the next commutation period T _n is determined based on the proportional calculation based on the integral value T _in of the next commutation period. Then, the process returns to step 32.

In the above-described embodiment, the DC motor without the commutator is driven as an example by setting the target zero cross time and determining the next rectification period so that the counter electromotive voltage signal occurs at the target zero cross time. It goes without saying that the present invention can also be applied to other things that drive control based on the cross point.

As described above, according to the present invention, since the last one is recognized as an effective counter electromotive voltage signal from the counter electromotive voltage applied during the current rectification to the next generation of rectification, the spike voltage is not affected. Since the counter voltage signal can be recognized accurately, accurate position detection is possible and safety driving can be improved.

Further, the effective counter electromotive force signal is generated at the target zero cross time by proportional and integral delays according to the difference between the target zero cross time to be provided by the effective counter electromotive voltage signal and the actual zero cross time to which the effective counter electromotive voltage signal is actually applied. Since the commutation period is set to be retracted, the commutation period is adjusted in proportion to the difference between the actual zero cross time and the target zero cross time as well as the integration result of the difference between the actual zero cross time and the target zero cross time. When the difference between the time and the target zero-cross time, i.e., the phase difference is large, the response is good, and safe driving can be further achieved. In addition, when the counter voltage signal can be applied from the current rectification to the next rectification, the current rectification cycle is set to zero cross time. You can continue to rotate. In addition, since the target zero cross time can be set to the j-th width of the current rectification cycle by k equals, the advance amount can be easily changed according to the change of k and j, and the advance amount control according to the load becomes possible. .

Claims (4)

A counter electromotive voltage signal generating means for imparting a counter electromotive voltage signal indicating a zero cross point of the counter electromotive voltage pulse-formed by comparing the counter electromotive voltage generated in the drive coil of the DC motor without a commutator with the neutral point potential of the drive coil, In a drive device of a rectifier-free DC motor for rectifying control of a drive coil in accordance with a control of a switching element in accordance with a signal, in the output of the counter electromotive force signal generating means applied during the generation of the current rectification to the generation of the next rectification. And a recognizing means for recognizing the last given as a valid counter electromotive voltage signal, and controlling rectification of the drive coil in accordance with the recognized effective counter electromotive voltage signal. And a counter electromotive voltage signal generating means for imparting a counter electromotive voltage signal representing a zero cross point of the counter electromotive voltage, pulse-shaped as a comparison of the counter electromotive voltage generated in the drive coil of the motor without a commutator with the neutral point potential of the drive coil. In a drive device of a rectifier-free DC motor for rectifying control of a drive coil in accordance with a control of a switching element in accordance with a voltage signal, in the output of the counter electromotive force signal generating means applied during the generation of the current rectification to the generation of the next rectification. The actual zero cross time detecting means for giving the last time given to the effective counter voltage signal generation as the actual zero cross time, and the target zero cross time for which the counter voltage signal valid for this rectification generation is to be given are assigned to this rectifying cycle. A target zero cross time setting means set on the basis of Means for determining the difference between the target zero cross time and the actual zero cross time and determining the next rectification cycle according to the proportional / integral operation according to the difference so that a valid counter voltage signal occurs at the target zero cross time. And a rectifier for controlling the commutation of the drive coil according to the determined rectification cycle. 3. The method according to claim 2, wherein if the actual zero cross time detecting means cannot give an output of the counter electromotive force signal generating means from the time of occurrence of the current rectification to the next time of occurrence of rectification, the current rectification period is given as the actual zero cross time. Drive device for a DC motor without a commutator. 3. The rectifying cycle determining means according to claim 2, wherein the target zero cross time setting means sets the target zero cross time in a time width up to the j th time by dividing the current rectification period by k equals. Formula Where T _in is the integral of the next rectification cycle, K _i is the integral constant, T _n-1 is the difference between the target zero cross time and the actual zero cross time, T _in-1 is the integral of the current rectification cycle, T _n is the next rectification cycle, and K _p is the proportional constant. The drive device of the DC motor without a commutator, characterized in that determining the.