DE2102981B2 - CIRCUIT ARRANGEMENT FOR THE FORMING OF AN ANGLE OF ROTATION INTO A PROPORTIONAL DC VOLTAGE - Google Patents

Description

a) an encoding stage (11) whose input zugswechselspannung the three rotor output signals (A, B, C) and a loading ^'5 (U receives ₀₎ and at the output of the three first logic signals (a, b, c) with such polarities can be tapped that den.11 combination defines a sextant (S) of the rotor rotation angle (<i);

b) a first logic circuit (13) connected downstream of the coding stage (11). which, as a function of the first three logic signals (ti, b. c ), supplies six indicator _{signals (F 0.} F _1. F _1. F,. F _4. F ₅ ) for marking the sextant of the rotor rotation angle (a);

c) a voltage level generator (14) controlled by the indicator signals. the sextant marked by the indicator signals at its output for jtΛ.η supplies a different DC voltage (K ₁ );

d) a ^{second logic circuit (16) acted upon by the indicator signals | j} * n and the rotor output signals, at the output of which an alternating voltage ( U ₁ ,) can be tapped, which is opposite the reference alternating voltage by a certain phase angle {(->) is offset, which corresponds to the deflection of the rotor rotation angle within its sextant;

e) a Phasenmeßstufe (17), wclcheram input the output voltage (l _'H) of the second logic circuit (16) and the reference alternating voltage (U are fed ₀₎ and at the output of a said phase angle ((·>) proportional DC voltage (V ₂ ) can be tapped;

a summing stage (18) in which the direct voltage marking the sextant of the rotor rotation angle and the direct voltage corresponding to said phase angle are added to a direct voltage (V) representing the rotor rotation angle.

2. Circuit arrangement according to claim 1, characterized in that the second logical Circuit (16) has the following features:

g) a first selection circuit (61, 62, 63. k ", K ₇ , K ₈ ) which, under control of the indicator _{signals (F 0} to F ₅ ), optionally lets one of the three rotor output signals (/ 1. ß. C) through;

h) a phase shifter (64, 65, 66. K ₉ , K ₁₀ ). which, under control by the indicator signals, rotates the rotor output signal passed by the first selection circuit either leading or lagging by 90;

i) a second selection circuit (K ,, to K ₅ ) which, under control by the indicator signals, selectively one of the six possible and by the factor | 3 passes divided difference signals between two of the three rotor output signals;

j) such a control of the two selection circuits and of the phase shifter by the indicator signals that the vector sum of the output signals of the phase shifter and the second selection circuit ( ± j L 1 and L ₄ ) formed at a summing amplifier "(10 ) with respect to the reference alternating voltage ((' ₀ ) "is offset by the said phase angle (H) .

3. Circuit arrangement according to claim 2, characterized in that the phase shifter consists of a W phase rotation device (64) and a downstream inverter (65) which is controlled by a switching device \ K _{controlled by indicator signals (/ '". F:.} F ₄₎ ,. K ₁ ,,) can optionally be bridged.

4. Circuit arrangement according to claim 2 or 3, characterized in that the / wide selection circuit contains six differential amplifiers [A _n to A ^) , each of which receives two of the rotor output signals M. B. C) and each of which receives one of a separate indicator signal (F ,, to F,) controllable switch (K “hi-K ₅ ) is connected downstream.

The invention relates to a circuit arrangement for reshaping the angular position of the rotor of a synchronous machine with three against each other, each by 120 staggered tube winding ^ ;, in a dem Rotoid rotation angle proportional DC voltage, from where the angular position is derived from the three alternating voltages that can be tapped off at the rotor windings which, as rotor output signals, each have a phase shift of 120 relative to one another. The intended field of application of the invention is an analog computer in which the angle of rotation a synchronous machine is a parameter that is included in the calculation.

In a synchronous machine of the type mentioned above, the stator which excites the rotor windings can be fed with an alternating current of, for example, 400 Hz. When the rotor of a receiving machine of the same construction is fed by currents which is removed via three conductors from three terminals of a synchronous transmission machine the rotor of the receiving machine adjusts itself electrically according to the rotation of the transmission machine a. In order to receive a direct voltage proportional to the angle of rotation of the transmission machine It is sufficient to pass the rotor of a precision potentiometer through the rotor of the receiving machine to drive. In this way, however, only a mediocre accuracy can be achieved, because a synchronous receiving machine has a very weak moment and the lowest resistance moment prevents the theoretically exact setting from being achieved. The accuracy of such Setting is thus limited to, for example, +2, which is insufficient for many abundances.

It is known to remedy this disadvantage by means of a locking device. The reception machine can namely, under favorable conditions, carry a light visor with you, on which a local control drive device the control unit, for example the potentiometer runner, adjusts. Such a facility, which provides an accuracy of iü.5, corresponds to the usual practice today.

However, such a device has disadvantages, in particular it is relatively heavy and needs a relatively large amount of space. For example is ι., "'in a ship in which to evaluate the results given by an echo sounder require a correction of the ship's speed is, a measured value of this speed on the navigating bridge in the form of an angle of rotation synchronous machine available, which by the airspeed indicator is driven. Since the echo sounder / unearthed Computer in a narrow stowage space of the ship ·, uitei must be brought. is it desirable. / ui l'm-ii iiiiuii !! the angle of rotation of the synchronous machine in t, .ic proportional DC voltage a space-saving ! provision to be made.

s is therefore the object of the invention, the conversion an angle of rotation into a proportional DC voltage in a purely electrical way, because one uses electrical shah assemblies ■ can be designed with smaller dimensions than the moving ! i..he mechanical parts.

Based on a circuit arrangement of the type described at the outset, this object is achieved according to the invention solved by combining the following features:

, ti a coding stage, the input of which is the three rotor output signals and receives a reference AC voltage and at its output three first logical ones Signals with such polarity can be tapped, that their combination defines a sextant of the rotor rotation angle:

b) a first logical downstream of the coding stage Circuit which, depending on the three first logical signals, six indicator signals to mark the sextant of the rotor rotation angle delivers:

c) a voltage level generalor controlled by the indicator signals, which at its output a different DC voltage for each sextant marked by the indicator signals supplies;

d) one of the indicator signals and the rotor output signals applied second logic circuit, at the output of which an alternating voltage can be tapped, which is against the reference alternating voltage is offset by a certain phase angle, which corresponds to the deflection of the rotor rotation angle corresponds within his sextant;

e) a phase measuring stage, which has the output voltage of the second logic circuit at the input and the reference alternating voltage are supplied, and at the output one of the said DC voltage proportional to the phase angle can be tapped;

f) a summing step ". in which the sextants of the Roiordrehwinkel marking DC voltage and the said phase angle corresponding DC voltage added to a DC voltage representing the rotor rotation angle will.

In the invention, the angle to be reshaped is represented by two summands: η = S · 60 + (■). S 'is an integer between 0 and 5. The whole Krvis is thus divided into six sextants, so that a measure for the angle α is formed from the ordinal number of the sextant S and an overflow β.

The principle according to the invention consists in deriving logical signals by comparing three alternating voltages, which are obtained by combining the terminals of a synchronous machine in pairs, with which the sextant of the rotor rotation angle can be delineated. The first logic circuit adopts this definition. In the voltage step generator to the definition made is then accordingly the value Λ ..toportionalcs Gleieh voltage level set the same time via the / logic circuit and the Phasenmeßstufe wide generates a DC voltage corresponding to the t'berlauf (-> ie de exact rash. *. Rotor rotation angle within the defined sextant S ".

proportion.il is. By adding both DC voltages the output signal proportional to the entire rotation angle is then obtained

In an advantageous embodiment of the I rfmdung contains the second logic circuit a first selection circuit, which optionally one of the three rotor output signals punctures, as well as a phase shifter, optionally leading the rotor output signal passed by the first selection circuit or lagging 90 out of phase, and schheßhch a second selection circuit, which optionally one of the six possible and divided by the laki.ir ι 3 DilTerenzsignale between two of the three rotor output signals passes. The indicator signals determine the first logic circuit.

which signals are allowed to pass by the selection circuits and in which direction the Phase rotation of the phase shifter takes place

The selection circuits and the phase shifter are controlled by the indicator signals in such a way that the vector sum of the output signals of the phase shifter and the second selection circuit is offset from the reference AC voltage by said phase angle (ie by the partial angle (-)).

5 "> Further details of the invention are provided below explained using an exemplary embodiment with reference to the drawings.

E i g. 1 shows the circle divided into sextants with an angle shown for example in sextant 3 ":

Fig. 2 shows a block diagram of the entire invention Circuit arrangement;

F i g. 3 is a block diagram of the invention Coding level:

F i j. 4 shows a block diagram of the first logic circuit according to the invention:

F i g. 5 shows a block diagram of the second logic circuit according to the invention;

F i g. 6 illustrates in a vector diagram the formation of the phase measuring stage phase-shifted alternating voltage.

As in Fig. 1, six sextants can be distinguished on the reference circle, which start with 0 to 5

are numbered. An angle ”as shown in FIG. 1 is specified. is formed by the sum of an integer number of sextants S = s ■ 60 with .s = 3 and an overflow θ , so that = s ■ 60 + θ results.

According to the illustration in FIG. 2, a synchronous machine 10 with three rotor windings arranged at 120 °, which is fed, for example, at a frequency of 400 Hz by a stator (not shown), supplies three alternating voltages T ₁ , T ₂ to three output terminals P. Q, R , T ₃ , from which three single-phase voltages A, ß, C are taken,

A between T, and T ₃ ,
B between T ₃ and T ₂ ,
C between T ₂ and T ₁ ,

where A, ß, C each represent the following values:

A = K sin « B = K sin (-i + 120")

C = K sin (»ζ + 240 °) with K = E ₀ cos <<> t.

It can also be written:

-A = K sin (/ i - 180 °)
- B = K sin (u - 60 °)
-C = K sin («+ 60 °)

Using a reference phase 12 supplied by the 400 Hz network, the synchronous sampling performed by a comparator 11 by an arrangement shown below in FIG. 3, logic signals a, b, c, the polarity of which changes + or - according to the value of s in accordance with the following table:

S. A. B. C. 0 + + - 1
-) ⁺ ₊ 3 _ + ' 4th - + + ⁺

With these three signals a, b, c , a logic 13 forms six logic functions F ₀ , Fi, ... F ₅ . of which only one in the sextant with the same index is equal to 0 and the five others are equal to 1: for example in the sextant 0. F _p = 0, F, = F ₂ ... F ₅ = 1. etc. The structure of the logic 13 is described below (see Fig. 4).

Each of the functions F ₀ ... F ₅ is received on the one hand in a voltage stage generator 14 which is fed by a DC reference voltage 15. The generator 14 supplies a voltage scale V ₁ = KS, where K is an integer, the value of which has the index of the voltage F, which is equal to zero

A logic 16 receives on the one hand the sinusoidal variables .4, BC on the other hand the functions F and supplies an alternating voltage U at the output, which forms an angle <-) with the reference alternating voltage U _0. The voltage U _h and the voltage U ₀ , which comes from the reference source 12 with 400 Hz, are fed to a phase measuring device 17, which on the other hand receives the reference voltage with 400 Hz U ₀ , which comes from a source 12 ' and a DC voltage at the output V ₁ = K ■ (-) yields.

A summation element 18, which receives the direct voltages Vl and Vl , supplies the voltage V on an output terminal 19, which is sought:

V = K (s ■ 60 "+ (-)) = K * <i.

The logic 16 is described with reference to FIG. 5 described. The phase measuring device 17 is any known device. For example, the voltages can be converted into logic signals, which are calibrated by classifying devices and fed to an exclusive OR circuit, which supplies square-wave pulses at the output with a width proportional to the phase shift (·). An integrator connected in series with the exclusive OR circuit supplies a direct voltage proportional to the angle (·).

In the same way, the summing device 18 can be any known device.

It is unnecessary to describe these known organs in detail because it makes the description unnecessary would be extended.

As shown in FIG. 3, the comparator 11 comprises at the input three transformer transformers 21, 22. 23, the primary winding of which is between the terminals of the synchronous _{machine T 1} and T, (size A), T ₃ and T ₂ (size β). T ₂ and T, (size O

is switched.

A fourth transformer 20 with terminals 7 ₀ . T ₀ receives a reference voltage of 400 Hz U ₀ . The four transformers have their asymmetrical secondary windings with a terminal to ground and each have an output terminal f ₀ . / ,. t ₂ . / ,. A reference voltage E _{0 is} received at r ₀ , (, "delivers E ₀ sin- !, f ₂ delivers E ₀ sin (α + 120) Λ, delivers E _o sin (« + 240).
These four tensions are each divided by four

Classifying devices 24. 25. 26. 27 formed into square waves. The outputs of the classifying devices 25. "" 6. Π are each connected to the "Signal" input of the bistable flip-flops 30.31.32. These three bistable flip-flops 30, 31, 32 have a control "Frci-

that is connected in parallel with the output of a monostable multivibrator 29. which is downstream of a monostable flip-flop 28. which is acted upon by the output of the classic device 24. For a 400 Hz supply, the monostable multivibrator 28 has a relaxation time of the order of 600 as. while the monostable multivibrator 29 has a relaxation time of the order of 50 [is .

The bistable flip-flops 30. 31.32 deliver on delivery

output the logical signals a. b, c.

The operation of the facility is as follows: The monostable flip-flop 28, which has a positive edge which comes from the classifying device 24 when the voltage £ passes through zero.

causes the flip-flop 29 to tilt back: The flip-flop 29 therefore delivers a rectangular pulse, the duration of which extends between the time 600 and 650 μ * after the reference voltage has passed.

that is, symmetrically frames the point in time 625 ij.s, which represents H / T 4 at 400. This means that the logical signals «■ / '. c. in the area of the passage through the maximum of the corresponding sinusoidal clamping linger can be removed.

The outline of the representation in FIG. 4 is the logic 13 constructed in the following way:

The signals ah c arrive at three terminals. each with a, b. c and which are multiplied to six branches in parallel. which deliver the functions at the output:

F ₀ = a + h ■ c
F ₁ = if ~ / T * c

F ₂ = (TTjLiA.
F ₁ = a · b · Γ
F ₄ = F + ~ 7 (I.
F ₅ = <; · C · b

for branch 0.
for branch 1.
for the 2nd branch 2.
for the 2nd branch 3.
for branch 4.
for the branch5.

With reference to the table above and with the agreement + = 1. - = 0 results for ^ en Sextants 0

F ₀ = 0 and F ₁ ... F .. = 1

and for the sextant 1

F .. = 0 and F ... F, ... F. = I and so on.

The branch 0 comprises a logical OR-switch-HUm 41, which receives α and b , and a logical Ü ^ ÜD-switch 42, which receives c , and the output of 41.

Branch 1 contains an AND circuit 43, which receives at its two inputs, and an AND circuit 44, which receives b and c , and the output of 4: 1.

The branch 2 comprises an OR circuit ung 45 which receives α and c, and an AND Schaltuni-46 which mt b aufnim, an d the output of 45th

The branch comprises: an AND circuit 47, which receives c aiii of its two inputs, and a Ό N D circuit 48, which receives α and b , and the beginning of 47.

Branch 4 comprises an OR j circuit 49 , which receives b and c , and an AND circuit 50 which receives α , and the output of 49.

Branch 5 comprises an AND circuit 51 which receives b at its two inputs, and a Ϊ N D circuit 52 which receives α and r, and the output of 51 ... "

ii g. 5 shows that part of the circuit arrangement according to the invention which forms an alternating voltage U ₉ from the alternating voltages tapped off by the rotor and the logic r-connections F ₀ to F ₅ , which is offset by the phase angle θ with respect to the reference _{alternating voltage L 0.} Like the vector diagram of FIG. 6 shows, this is sent to the Pi.asenmeßgerat 17 <I · i g. 2) applied alternating voltage U _e by vector addition of an alternating voltage ± jU and an alternating voltage U ₄ . achieved.

The variable U ₁ is optionally one of the values A. ö. T, which, depending on the defined sextant:> via one of the three contacts K _f . K ₇ and K ₈ will be passed on. K ₆ is controlled by the output of an AND-Schaltune61, which is added by the functions F _n and F, ^. K i is controlled by an AND circuit 62 which _{receives F 1} and F ₄ , and K ₈ is controlled by an AND circuit 63 which receives _{F 2} and F _5. The signal U ₁ obtained at c 1 is phase-shifted by 90 by a circuit 64.

For the sextants 1, 3 and 5, the phase ac \ of the obtained signal U _{1 must be} reversed. This phase reversal is carried out by an inverter circuit 65 connected in series with the circuit 64, which in the case of

ίο the sextants 1, 3 and 5 is inserted by a relay _{whose normally open contact K 9 is} at the output of circuit 65 and whose normally closed contact K _{10 is} at the input of circuit 65. This relay is controlled by the output of an AND circuit 66.

. 5 which receives the functions F ₀ , F ₂ and F _4.

At the common connection of contacts K _c) and K | ₀ , the quantity ij'U is obtained, which is applied to the input e _{4 of} an amplifier 70 via a resistor 67.

The variable U ₄ is obtained from the difference between two of the signals A, B and C, which are formed by six amplifiers A ₀ to / I ₅ with two inputs. The inputs are designated with e ₂ and c, respectively. A ₀ receives B and C [A ₁ receives A and C:

A ₂ receives A and ö; A ₃ receives B and C; A ₄ receives A and C; A ₅ receives A and B.

The output of each amplifier is in series with a normally closed contact K ₀ ... K ₅ , which is operated by the functions F _n ... F * . This contact is closed when the function F controlling it has the value zero. The common connection of the contacts K ₀ to K ₅ is connected via a resistor 68 to the input c _{4 of} the amplifier 7 (1. The input e ₄ is connected to a condenser.

sator 69 to ground to suppress harmonics, which can occur in the signals mentioned.

The scheme according to FIG. 5 is to be understood symbolically in reality the switches are electronic, off building blocks built on integrated circuits.

The following is the mode of operation of the in FIG. f explained logic circuit:

Three alternating voltages appear at inputs A, B and C:

AH sin (i

B = H sm (, i + 120)
C = fi sin (.. + 240)

The quantity H is here synonymous with E ₀ ■ cos i'tt. One of the voltages A. B and C wire is each selected as the variable U ₁ , while the other two voltages represent the variables U ₂ and U _3. An alternating voltage is now to be _{generated for U 4}

the. which is proportional to cos (-):

L ₄ = E ₀ · cos <■> t ■ cos H

Such an alternating voltage can be obtained by taking the difference between U ₂ and U ₃ . U ₂ can be written in the following form

U ₁ = - - E ₀ ■ COSmf I., Sin <-> - i— COS θ Ί

I) _{3 can be} broken down into the following! Write form:

U ₃ = -E ₀ - cos / ji 1_2

^ r cossi. 2 j

The element sin <■> is eliminated in the difference U ₂ - U _3. So one can get a U ₄ that fulfills the above requirements:

UU
U ₄ = = E ₀ · coso / · cos <-).

Such a U ₃ appears at the common output #er switches K ₀ to K _{5 of} the circuit according to FIG. 5.

If you turn the phase of the signal U ₁ by 90 °, you get:

JU ₁ = E ₀ sin «it ■ sin (-)

The vector sum of U ₄ and j U ₁ is:

U _e = E ₀ (cos int ■ cos θ + sin at (■))
= E ₀ cos ((D t - (-))

The signal Uf appearing at the output of the amplifier 70 thus forms the angle θ with the reference voltage

The logic circuit shown in Fig. 5 delivers the desired signal IZ ₈ when the switches K ₁ to K ₈ to are controlled so that in the various sextants S, the quantities A. B and C to the inputs C ₁ . C ₂ and t'i are placed as shown in the table below:

5

S. 'Ί B. C. 0 A. A. C. 1 B. A. B. 2 C. C. B. 3 A. C. A. 4th B. B. A. 5 C.

After generating a proportional to the phase angle tionalcn DC voltage in device 17 and addition of this DC voltage with that of the voltage levels generator 14 supplied and the relevant sextant corresponding DC voltage level receives may a very precise analog signal for the rotor rotation angle. With voltage levels of 1.2V each which are calibrated to an accuracy of 0.1 mV, what you can do without great difficulty results in you a total of 7.2 V for 360 °. Eil tenths of a degree corresponds to an amplitude of 2 mV The resolving power of the circuit arrangement according to the invention is therefore excellent.

1 sheet of drawings

Claims (1)

2 * J02 981 Patent claims: 1, circuit arrangement for reshaping the angular position of the rotor of a synchronous machine with three against each other, each offset by 120 ^ Rotor windings in a proportion to the rotor rotation angle? DC voltage, the angular position is derived from the three alternating voltages that can be transferred to the rotor windings, each having a phase shift of 120 'from one another as rotor output signals, characterized by the combination of the following features: