JPS6231597B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a commutatorless motor, and particularly to a control device for a commutatorless motor applied to the field of numerical control.

FIG. 1 is a block diagram of a control device for a DC motor applied to conventional numerical control. In the figure, 1 is a subtracter that subtracts the output b of the position detecting means 7 described later from the position command a, 2 is a subtracter that subtracts the output d of the speed detecting means 6 described later from the position error c which is the output of the subtracter 1, 3 is an amplifier for driving the DC motor 4. 5 is a resolver mechanically coupled to the rotor of the DC motor 4 to detect the position or speed of a saddle, etc. 6 is a speed detection means for detecting the speed based on the output of the resolver 5; 7 is also a resolver This is a position detecting means for detecting a position based on the output of 5.

In FIG. 1, the DC motor 4 has brushes and a commutator, which can be a cause of failure. Therefore, regular maintenance and inspection are required to maintain stable operation. This, combined with the labor shortage and rising labor costs in recent years, has become a major problem for users who continuously use a large number of DC motors. If an attempt is made to use a commutatorless motor instead of a DC motor in order to eliminate this drawback, the following control block diagram may be considered.

FIG. 2 is a conventional control block diagram based on FIG. 1, in which a commutatorless motor is used in the field of numerical control. In the figures, elements with the same numbers as in FIG. 1 indicate the same elements. 8 is a non-commutated motor, and 9 is a distributor that detects the rotation angle of the rotor of the non-commutated motor. 10 is the distributor 9
11 is an amplifier that amplifies the output of the subtracter 2 based on the output of the distributor output amplifier 10.

In Fig. 2, as a result of using a non-commutator motor, there are no brushes, commutators, etc. like in a DC machine, but a distributor is newly required, and a resolver output is used as in the present invention. Therefore, the distributor could not function properly. Therefore, the surroundings of the machine are a little complicated.

FIG. 3 is a block diagram of a known method in which not only the rotation angle but also the speed of the rotor is detected using a distributor of a non-commutated motor. In the figures, elements with the same numbers as in FIGS. 1 and 2 indicate the same elements. Reference numeral 12 denotes speed detection means for detecting speed based on the distributor 9.

In FIG. 3, although it is possible to detect the rotation angle and speed of the rotor, highly accurate speed control is not possible. Therefore, it is actually difficult to control the position on the numerically controlled axis. If one attempts to perform position control using numerical control in order to eliminate this drawback, the following control block shown in FIG. 4 can be considered.

FIG. 4 is a conventional control block diagram based on FIG. 3, in which a commutatorless motor is used in the field of numerical control. Figures 1 to 3 in the figure
Elements with the same numbers as those shown in the figures indicate the same elements. In order to control the position on the numerically controlled axis, a resolver 5 and other position detectors are newly required as shown in the figure, and the function of the distributor is performed using the resolver output as in the present invention. I couldn't do it. Therefore, as in the case of FIG. 2, the surroundings of the machine become complicated. Also Tokukai Akira
As described in No. 53-140524, it is known to detect and control the rotation angle using a resolver in a commutatorless motor.

Therefore, an object of the present invention is to enable the rotation angle, speed, and position on the numerical control axis of the rotor to be shared by the output obtained from one resolver in the control of a non-commutated motor used for numerical control. This is intended to be detected using a special circuit configuration.

FIG. 5 is a control block diagram of one embodiment of the present invention, and elements having the same numbers as in FIGS. 1 to 4 indicate the same elements. In FIG. 5, 13 is the resolver 5.
This is a rotor rotation angle detection means for detecting the rotation angle of the rotor based on the output of the rotor, and is a characteristic element of the present invention. Reference numeral 14 denotes an amplifier for amplifying the output of the subtracter 2 based on the output of the rotor rotation angle detection means to drive the commutatorless motor.

FIG. 6 is a control block diagram of one embodiment of FIG. 5 in more detail. In this figure, the same numbers as in FIGS. 1 to 5 indicate the same elements. 21 is an excitation oscillator for the resolver 5, and the oscillator output is transmitted to the speed detection means 6, the position detection means 7,
It serves as one input of the rotor rotation angle detection means 13. The speed detecting means 6 inputs the output of the oscillator 21 and the output of the resolver 5 and extracts the speed. The position detecting means 7 similarly receives the output of the oscillator 21 and the output of the resolver 5 to obtain the position, and this is already known. Next, the rotor rotation angle detection means 13
One embodiment of this will be described. 22 is a waveform shaper that shapes the output of the resolver 5;
is the output of the waveform shaper to 1/3 of the resolver excitation waveform.
A first delay circuit 24 is a second delay circuit for delaying the output of the waveform shaper by 2/3 cycles of the resolver excitation waveform. 2
5 is a first pulse generator that emits an output when the output of the waveform shaper 22 rises, 26 is a second pulse generator that emits an output when the output of the first delay circuit 23 rises, and 27 is the output of the second delay circuit 24. This is a third pulse generator that outputs an output at the rising edge of . 28 sets the excitation waveform of the resolver 5 to the first
A first sampling and hold circuit 29 samples the excitation waveform of the resolver 5 at the output of the pulse generator 25 of the second pulse generator 26.
A second sampling and holding circuit 30 samples the output of the third pulse generator 27, and a third sampling and holding circuit 30 samples the excitation waveform of the resolver 5 at the output of the third pulse generator 27.
Next, one embodiment of the amplifier 14 will be described. 31 is a first circuit that multiplies the output of the first sampling and hold circuit 28 and the output of the subtracter 2;
32 is a second multiplier that multiplies the output of the second sampling and hold circuit 29 and the output of the subtracter 2; 33 is a multiplier that multiplies the output of the third sampling and hold circuit 30 and the output of the subtracter 2; This is the third multiplier that multiplies . Numerals 34, 35, and 36 amplify the outputs of the first multiplier, second multiplier, and third multiplier, respectively, and supply current to the three-phase armature windings of the commutatorless motor 8. It is a vessel.

FIG. 7 is a diagram showing waveforms of important parts in FIG. 6. In the figure, the waveform of f is the same as the output waveform of the oscillator 21, and has a frequency of, for example, 10 KHz, and To is the time of one cycle. g
The waveform is the output waveform of the early resolver 5, and while the resolver is rotating, the period is _T1 , which is different from the period To of the excitation frequency, as shown in the figure. h is the output of the waveform shaper 22, i is the first delay circuit output, and j is the second delay circuit output. k is the first pulse generator 25 output, as shown
Occurs at times t ₁₁ , t ₂₁ , t ₃₁ , t ₄₁ . In the figure, a ₁ , a ₂ , a ₃ , a ₄ ...... are t ₁₁ , respectively
These are outputs sampled by the first sampling and hold circuit 28 at times t ₂₁ , t ₃₁ , t ₄₁ . 1 is the output of the second pulse generator 26 and is generated at times t ₁₂ , t ₂₂ , t ₃₂ , . . . as shown. In the figure, b ₁ , b ₂ , b ₃ , ...... are each
These are outputs sampled by the second sampling and hold circuit 29 at times t ₁₂ , t ₂₂ , t ₃₂ , . . . . m is the output of the third pulse generator 27 and is generated at times t ₁₃ , t ₂₃ , t ₃₈ . . . as shown in the figure. In the figure, c ₁ , c ₂ , c ₃ , ...... are respectively
These are outputs sampled by the third sampling and hold circuit 30 at times t ₁₃ , t ₂₃ , t _{33 ,} . . . .

FIG. 8 shows the sampling values a ₁ shown in FIG. 7,
a ₂ , a ₃ , a ₄ , ...... and b ₁ , b ₂ , b ₃ , ...... and c ₁ ,
This is a diagram plotting c ₂ , c ₃ , ..., respectively. In the figure, p, g, and r are the outputs of the first sampling and holding circuit 28, the second sampling and holding circuit 29, and the third sampling and holding circuit 30, respectively, and as shown in the figure, when the rotor of the resolver 5 rotates once, It draws a sine curve of one period with a phase shift of 120 degrees. That is, if the rotor rotation angle detection means 13 of the present invention is used, 120
This makes it possible to extract sine curves whose phases are shifted by degrees. Therefore, it is possible to detect the rotation angle of the rotor of a non-commutated electric motor, and it becomes possible to have the three functions of position detection means, speed detection means, and rotor rotation angle detection means with one resolver. .

FIG. 9 is a control block diagram of another embodiment of the present invention, in which elements with the same numbers as in FIG. 6 indicate the same elements. In FIG. 9, numeral 37 is an adder that inverts the signs of the output of the multiplier 31 and the output of the multiplier 32 and adds them. Compared to FIG. 6, the second delay circuit 24, the third pulse generator 27, the third
Sampling hold circuit 30, third multiplier 33
It is possible to have a configuration in which . The reason is that the output u of the multiplier 31, the output v of the multiplier 32,
There is a relationship u+v+w=o between the outputs w of the multiplier 32, and two of u, v, and w, for example, u, v
This is because if w is known, other w can be obtained computationally.

FIG. 10 is a control block diagram of yet another embodiment. Elements with the same numbers as in FIGS. 6 and 9 mean the same elements. In FIG. 10, 38 is a multiplier that multiplies the output f of the excitation oscillator 21 and the output e of the subtracter 2. 39 is a first sampling and hold circuit that samples the output of the multiplier 38 using the output of the first pulse generator 25, and 40 samples the output of the multiplier 38 using the output of the second pulse generator 26. This is a second sampling and hold circuit that samples . Book 10
Comparing this figure with FIG. 9, the structure is that one multiplier is placed before the sampling and holding circuit in order to omit one, but they are essentially the same.

As explained above, according to the present invention, a special circuit is provided as a rotor rotation angle detection means for detecting the rotation angle of the rotor of a commutatorless motor based on a resolver, so that the rotation angle of the rotor can be detected by the resolver. This can be done easily and accurately. Therefore, if a commutatorless motor to which the present invention is applied is used for numerical control, the mechanical structure can be simplified and the inherent merits of a commutatorless motor, which does not have brushes or a commutator, can be fully utilized. be.

[Brief explanation of the drawing]

Fig. 1 is a control block diagram of a DC motor applied to conventional numerical control, Fig. 2 is a conventional control block diagram based on Fig. 1, and Fig. 3 is a control block diagram of a conventional non-commutator motor. FIG. 4 is a conventional control block diagram based on FIG. 3, FIG. 5 is a control block diagram of one embodiment of the present invention, FIG. 6 is a detailed control block diagram of FIG. 5, and FIG. FIG. 8 is a diagram showing the waveforms of the main parts in FIG. 6, FIG. 8 is a diagram showing the output values p, q, and r of the sampling and holding circuit in FIG. 7, and FIG. 9 is a diagram showing another embodiment which is a modification of FIG. 6. Control Block Diagram FIG. 10 is a control block diagram of another embodiment which is a modification of FIG. 9. 4...DC motor, 5...Resolver, 6...Speed detection means, 7...Position detection means, 8...Commutatorless motor, 9...Distributor, 10...Distributor output amplifier, 11 ... amplifier, 12 ... speed detection means,
13... Rotor rotation angle detection means, 14... Amplifier, 21... Excitation oscillator, 22... Waveform shaper,
23...first delay circuit, 24...second delay circuit,
25...First pulse generator, 26...Second pulse generator, 27...Third pulse generator, 28...First sampling and hold circuit, 29...Second sampling and holding circuit, 30...Third Sampling and holding circuit, 37... Adder, 38... Multiplier, 39... First sampling and holding circuit, 4
0...Second sampling and hold circuit.

Claims (1)

[Claims] 1. A waveform shaper that shapes the resolver output mechanically coupled to the rotor shaft of the non-commutated motor, and a first waveform shaper that delays the output of the waveform shaper by 1/3 period of the resolver excitation waveform. a delay circuit, a first pulse generator that emits an output when the output of the waveform shaper rises, a second pulse generator that emits an output when the output of the first delay circuit rises, and an excitation waveform of the resolver. a first sampling and holding circuit that samples the excitation waveform of the resolver using the output of the first pulse generator; and a second sampling and holding circuit that samples the excitation waveform of the resolver using the output of the second pulse generator. Control device for commutatorless motor. 2. A waveform shaper that shapes the resolver output mechanically coupled to the rotor shaft of the non-commutated motor, and a first delay circuit that delays the waveform shaper output by 1/3 cycle of the resolver excitation waveform. a second delay circuit that delays the resolver excitation waveform by 2/3 cycles;
a first pulse generator that emits an output when the waveform shaper output rises, a second pulse generator that emits an output when the first delay circuit output rises, and a second pulse generator that emits an output when the second delay circuit output rises; a third pulse generator that generates an output; a first sampling and hold circuit that samples the excitation waveform of the resolver using the output of the first pulse generator; and a third pulse generator that samples the excitation waveform of the resolver with the output of the first pulse generator A control device for a non-commutator motor, comprising a second sampling and holding circuit that samples the output of the resolver, and a third sampling and holding circuit that samples the excitation waveform of the resolver using the output of the third pulse generator. 3 a waveform shaper that shapes the resolver output mechanically coupled to the rotor shaft of the non-commutated motor; a first delay circuit that delays the waveform shaper output by 1/3 period of the resolver excitation waveform; a first pulse generator that emits an output when the waveform shaper output rises; a second pulse generator that emits an output when the first delay circuit output rises; and an excitation waveform output of the resolver and a speed error e. a first sampling and hold circuit that samples the multiplier output at the output of the first pulse generator; and a first sampling and hold circuit that also samples the output of the multiplier at the output of the second pulse generator. A control device for a non-commutator motor, comprising a second sampling and hold circuit.