JPS62287163A - Resolver speed detecting circuit - Google Patents

Abstract

PURPOSE:To perform speed detection with high accuracy by detecting the rotating speed of an electric motor, etc., by using the output of a resolver. CONSTITUTION:A reference signal generating circuit 1 generates exciting signal generating clock pulses for resolver exciting signal generation and count pulses for a counter circuit 61. The exciting signal generating clock pulses are inputted to an exciting circuit 2, which generates sine wave signals V1sinomegat and V1cosomegat to excite the resolver 3. A sine wave KV1sin(omegat-thetar) corresponding to the position thetar of the rotor of the resolver 3 is induced at the rotor winding. A zero-cross circuit 41 generates the zero-cross pulse signal t1 of the leading edge of the sine wave signal, the circuit 61 count the counting pulses with the signal t1 to generate a sample pulse when counting up to a counted value corresponding to time t0=pi/omega, and its counting contents are reset. The sine signal is sampled and held 51 with this sample pulse to obtain an output proportional to speed information.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Industrial Application Field] The present invention relates to a resolver speed detection system in which the rotational speed of a motive device, etc. can be detected by the output of a resolver in an electric servo device. Regarding circuits.

[Conventional technology]

Generally, for example, in order to control the speed of an electric motor, it is necessary to detect the rotational speed of the electric motor. Conventionally, a tacho generator, an optical encoder f, etc. have been used to detect the rotational speed of an electric motor in this way.

[Problem that the invention seeks to solve]

However, since the above-mentioned tachogenerator is a type of generator, it has the disadvantage that it is made up of a variety of wear parts, which causes deterioration over time and generates noise due to sparks and the like. Also, optical encoders do not have sufficient reliability because they use components that change over time, such as photodiodes.

For this reason, there has been a desire for a speed detection method that can provide sufficient reliability even against changes over time.

Therefore, an object of the present invention is to solve the above-mentioned conventional problems,
An object of the present invention is to provide a highly reliable resolver speed detection circuit that detects the rotational speed of an electric motor or the like using the output of a highly reliable resolver used as a position detector.

[Means for solving problems]

The resolver speed detection circuit according to the present invention includes (1) a reference signal generation circuit that generates a resolver excitation signal generation lock pulse and a counting cell 7; An excitation circuit that outputs a first two-phase sine wave signal and a second sine wave signal induced on the secondary side of the resolver detect the rising or falling zero loss and generate a zero cross pulse signal. The generated cross circuit and the above-mentioned spill loss/? A counter circuit having a 'Bt4e that starts counting the counting cell 7 based on the pulse damage signal and generates a sample pulse signal and resets the counting contents when a predetermined count value is reached; - A sample and hold circuit is provided which samples and holds the second sine wave signal using the signal and outputs speed information.

Furthermore, the resolver speed detection circuit according to the present invention includes (2):
A resolver excitation signal generation lock cell 7 and a reference signal generation circuit that generates a count/base pulse are inputted to the excitation signal generation lock cell 7.
An excitation circuit that outputs a phase sine wave signal and a zero cross point of a second sine wave signal induced on the secondary side of the resolver are detected,
A zero cross circuit that generates a rising cross pulse signal and a falling pulse signal, and the rising cross/mother pulse signal are used to start counting the count and pulse, and when a predetermined count value is reached. and a first sample pulse signal having a function of generating a first sample pulse signal and resetting counting contents.
The counter circuit and the falling 9-pulse cross pulse signal start counting the count and 2 pulses, and when a predetermined count value is reached, a second sample and 2 pulse signal is generated, and the counting contents are a second counter circuit having a function of resetting the W;

a first sample and hold circuit that samples and holds the second sine wave signal using a sample pulse signal of l;
a second sample and hold circuit that samples and holds the second sine wave signal using the second sample and two pulse signals, and subtracts the second sample and hold 11J from the first sample and hold value; It is characterized by comprising an addition circuit that outputs speed information.

[Effect]

In explaining the operation of the resolver speed detection circuit according to the present invention, the theory underlying the present invention will first be explained.

The resolver used is one with two-phase excitation and one-phase output as shown in FIG. In Fig. 3, the resolver excitation Ti1i
The signal is converted into a two-phase sine wave signal V1slnω with a fixed phase ωt.
t, VIQ) Sωt, resolver output X? i,
X = K V I (sinωt'czθ, some ω and
s'mθ, )=KV1 sln (ω is 10r) (K
: turns ratio)...! 1). The output winding of the resolver and the position of the gland are θ.

is not necessarily zero when the resolver excitation phase ωt is zero.

θ, = ωr1 + δ (ω,: Resolper output angular circumferential velocity δ:
? , 7th period value) (2).

Next, to explain the invention of (1) above, in equation (3), (ω-ωr)11-δ=2nπ (n: integer)
...(4) Find X11 after To (=) from tl. According to equation (4), substituting equation (6) into equation (3), = KV1sin (2nπ-1--r rr )ω = KV1s1rl(π-''π) ω = KV, other 2π
(7) In equation (7), the resolver excitation angular velocity ω is larger by the amount of the resolver output angular velocity obtained. That is, if ω〉ω, 'sm2π;'' becomes (7
) formula is ω ω xt =KV1−ω.

=KV, TOURr-...<8) becomes. This Xl is proportional to the speed information.

? :When explaining the invention of (2) above to K, (3)
In the formula, (ω-or)t2-δ=(2n+1)π (n: integer)
......(9) from t2 to To('') Xl
seek. (9) From the ω formula, t2 = attack~monido...seeq t2+To =■zuseseee1...haiω-ωr ω q〃2 Substituting into the equation (3), =- KV1 earth two pi ・
・Purn・・riaω Similarly to equation (8), if we set ω〉ω in the equation (8), then
X2=-KVIToω, ・
...-U:+Here, if we subtract Xl and Xl and set 7 as Xo, then Xo=X1-X, =2KVl'roω,
... By performing a-O, speed information can be obtained in the cow wheel 1 of the invention (1) above.

[Example] FIG. 1 is a diagram showing an example of the invention of (1) above,
1 is a reference signal generation circuit, 2 is an excitation circuit, 3 is a resolver,
4 is a zero cross circuit, 42 is a gicross circuit, 51 is a sample hold circuit, 52 is a sample hold circuit, 53
is a sample hold circuit, r +Ir+ +++y
J ri M g 25-hh y
1st E1! 6. 7 represents a counter circuit, and 7 represents an adder circuit. The reference signal generating circuit 1 generates a lock pulse for generating an excitation signal for generating a resolver excitation signal and a counting pulse for a counter circuit 61 to be described later. The excitation signal generation lock 9 pulse is input to the excitation circuit 2, and the excitation circuit 2 generates the first sine wave signal vls for excitation of the resolver.
tnωt, vICO5ω[ are generated and the resolver 3 is excited. The rotor winding of the resolver 3 receives a signal corresponding to the rotor position information θ, that is, a second sine wave signal KV.
t ground (ω - θ) is induced. A zero cross circuit 4 generates a zero cross pulse signal t1 at the rising edge of the second sine wave signal. The counter circuit 6 receives the zero cross pulse signal 1. Start counting the 9th ruth,
When the count value of ω corresponding to 1'\1To = 'tc is reached, a sandal pulse signal is generated,
And reset the counting contents. Sample hold circuit 5
1 is by sampling and holding the second sine wave signal using the sample zero signal, x, =KV
An output proportional to the speed information of I TaO2 is obtained.

FIG. 2 shows an embodiment of the invention (2) above, and the same parts as those shown in FIG. 1 are given the same reference numerals and will be described. 1
1 is a reference signal generating circuit which generates an excitation signal generation lock signal for generating a resolver excitation signal and a count signal for counter circuits 62 and 63 to be described later. The excitation signal generation lock 9 pulse is input to the excitation circuit 2, and the excitation circuit 2 generates the first sine wave signal V1s+ for excitation of the laser/lupa.
nωt and V1CQSωt are generated to excite the resolver 3. The rotor winding of the resolver 3 contains rotor position information θ,
, that is, the second sine wave signal KV1sj
The zero cross circuit 42 receives the zero cross malus signal t at the rising edge of the second sine wave signal.
1 and falling spill Rossno! A pulse signal t2 is generated.

The counter circuit 62 receives the rising zero cross pulse signal 1.
According to ゜, counting of the above-mentioned counting) 4 ruses is started, and the time T0=
When the count value corresponds to -, a sample pulse signal is generated and the contents of the count are reset. Similarly, the counter circuit 63 receives the falling zero cross pulse signal t2.
Accordingly, the above-mentioned counting starts counting the 9th pulse, and the time To=
When a count value corresponding to ωω is reached, a sample malus signal is generated and the count contents are reset. The sample hold circuit 52 uses the sample/zero signal output from the counter circuit 62 to
By sampling and holding the second sine wave signal, an output of xl''KVI TOω is obtained.Similarly, the second sine wave signal is By sampling and holding the sine wave signal, X, = -KVIT
0ω, I got a good idea. Then, in the adder circuit 7,
By executing step 2, an output proportional to the speed information xo = 2KV, T2O, is obtained.

As described above, each implementation of the present invention has the following characteristics.

(1) Resolver and 1j used as position detectors
Speed information can be obtained by a simple circuit configuration.

(2) According to the embodiment of the invention of (2) above, the above (
Speed information can be obtained in cow cycles with twice the output as in the invention of 1).

[Advantageous Effects of the Invention] As described above, according to the present invention, the rotational speed of an electric motor, etc. can be obtained by using the output of a resolver, which is a position detector, without using a conventional tough generator, optical encoder, etc. This provides excellent effects such as highly reliable speed detection.

[Brief explanation of the drawing]

1 and 2 are Pcock diagrams showing the configuration of an embodiment of the present invention, and FIG. 3 is a diagram showing the principle of a resolver used in the present invention. 1... Reference signal generation circuit, 2... Excitation circuit, 3...
・Resolver, 4)... Zero cross circuit, 42... Zero cross circuit, 5... Sample hold circuit, 52...
- Sample hold circuit, 53... Sample hold circuit, 61... Counter circuit, 62... Counter circuit, 63... Counter circuit, 7... Adder circuit.

Claims (2)

[Claims] (1) A reference signal generation circuit that generates excitation signal generation clock pulses and counting pulses; an excitation circuit that receives the excitation signal generation clock pulses and outputs a first two-phase sine wave signal for excitation of the resolver; a zero cross circuit that detects the rising or falling zero cross point of the second sine wave signal induced on the secondary side of the second sine wave signal and generates a zero cross pulse signal; a counter circuit that starts counting and has a function of generating a sample pulse signal and resetting the counting contents when a predetermined count value is reached; A resolver speed detection circuit comprising a sample and hold circuit that samples and holds and outputs speed information. (2) a reference signal generation circuit that generates excitation signal generation clock pulses and counting pulses; an excitation circuit that receives the excitation signal generation clock pulses and outputs a first two-phase sine wave signal for excitation of the resolver; A zero cross circuit that detects a zero cross point of a second sine wave signal induced on the secondary side of the sine wave signal and generates a rising zero cross pulse signal and a falling zero cross pulse signal, and the rising zero cross pulse signal, a first counter circuit having a function of starting counting the counting pulses, generating a first sample pulse signal when a predetermined count value is reached, and resetting the counting contents; and the falling zero cross pulse signal. a second counter circuit that starts counting the counting pulses, generates a second sample pulse signal when a predetermined count value is reached, and resets the counting contents; a first sample and hold circuit that samples and holds the second sine wave signal using the sample pulse signal; and a second sample and hold circuit that samples and holds the second sine wave signal using the second sample pulse signal. a hold circuit;
A resolver speed detection circuit comprising: an addition circuit that subtracts the second sample hold value from the first sample hold value and outputs speed information.