JPS591399Y2 - Abnormality detection device for rotor connection conductors - Google Patents

Description

[Detailed description of the invention] This invention detects abnormalities in a plurality of connecting conductors arranged on a rotor of a rotor of a rotating electric machine, for example, connecting a rotating armature and a rotating rectifier. It is related to the device.

For rotors with rotating rectifiers, detection is performed when one of the many parallel protective fuses installed in each arm blows out, or if no fuse is installed, detection is performed when one diode is damaged. The purpose is to detect overcurrent due to

As a method for detecting a fuse blowout in a rotary rectifier of a rotary exciter, there has been known a method as disclosed in Patent Application Publication No. 45-23449.

In this method, the current flowing through the diode is detected by a detection element, and a signal from the detection element is selected and made conductive to the alarm device.

A synchronous pulse controller was required for this signal selection.

This is because the voltage induced in the detection element is affected by the current flowing through multiple connected conductors, resulting in a complex waveform even when each conductor is normal, and when a fuse blows, its appearance varies depending on the blowing conditions, making it even more difficult to distinguish. Therefore, some method of signal selection was required.

However, in this method, the selected time of the synchronous pulse is affected by changes in the internal phase angle due to changes in the output of the rotating electrical machine, and the current flow time shifts, making the device complex and making it extremely difficult to put it into practical use. It was.

This invention eliminates the above-mentioned drawbacks of the conventional device and provides a device that can detect abnormalities in a simple manner and even in connection conductors with various configurations.

As an example of a rotor to which this invention is applied, a fuse blowout detection device for a rotary rectifier will be described.

FIG. 1 shows a principle diagram of a brushless excitation device having a rotary rectifier.

Reference numeral 1 indicates a synchronous machine, 2 indicates an armature of a stator of the synchronous machine, 3 indicates a rotating field of the synchronous machine, and 4 indicates a rotor directly connected to the synchronous machine and the brushless exciter machine.

5 is a rotating rectifier, 6 is an AC exciter, and the stator field 7 is
and a rotating armature 8.

Reference numeral 9 denotes a sub-exciter, which includes a rotating field 10 made of a permanent magnet and an armature 11 of a stator.

12 is an automatic voltage regulator that adjusts the DC field current to the AC exciter 6, and 13 is a plurality of connecting conductors that connect the armature 8 of the AC exciter 6 and the rotary rectifier 5.

FIG. 2 is an explanatory diagram showing an outline of the rotor portion of the AC exciter 6 shown in FIG.

The armature 8 is human-wired and has two parallel circuits for each phase, which are grouped together for each phase by a phase ring 14.

The rotary rectifier 5 is a three-phase full-wave connection, IS-3P.
-6A (1 series of diodes 5a for each phase are made into 3 parallel circuits, +.

It has a total of 6 arms).

The connecting conductor 13 is connected to the phase ring 14 for each phase and the diode 5a2 circuit (+ side and one side), and is configured with three conductors for each phase.

Although details of the rectifier are omitted in FIG. 2, a fuse for protection is connected in series to each diode 5a.

In the device configured as described above, when the rotor 4 is rotated and an excitation current is passed through the field 7, a three-phase alternating current is generated in the armature 8.

This alternating current is rectified by a rotating rectifier 5 and supplied to a rotating field 3 of a synchronous machine.

Although alternating current flows through the connecting conductor 13, the rectifier 5 conducts current at an electrical angle of 120 degrees (half-wave 18
Therefore, the position of the detection element that detects the induced voltage due to this current flowing on the fixed side of the connecting conductor 13 must naturally be in the current flowing region around the rotor.

Furthermore, in order to set the detection element, it is necessary to know this energized region.

However, the energization range changes depending on the design details of the AC exciter 6 and the connecting conductor 13, and is complicated due to a large number of parameters.

Figure 3 shows the relationship between the armature of the AC exciter and the connecting conductors.

The field 7 has a plurality of magnetic poles 15, and in the rotating armature 8, an armature coil 16 having a certain phase band has one end connected to the phase ring 14.
The other end is connected to the neutral ring 17.

The number of connection conductors 13 is generally determined by the configuration of the rectifier circuit, and is regularly distributed on the rotor axis.

FIG. 4 shows a cross-sectional view of an example of the arrangement of the connecting conductor portions.

A non-magnetic ring 19 is shrink-fitted to the rotor shaft 18.

The connecting conductors 13 are arranged at equal intervals as shown in the figure, for example, through an insulating member 20, and are fixed with a fixing band 21 such as an epoxy glass band.

The energization of the armature coil 16 is determined by the relationship between the pole and the phase resistor.

The angle A between the phase belt center and the connecting conductor 13 (see Figure 3) is:
Number of poles, armature coil winding method, phase sequence, rotation direction, number of phases,
It is determined by the presence or absence of the phase ring 14, the number of connecting conductors 13, the arrangement method, etc.

An energization reference point on the fixed side facing the connection conductor 13 is determined by the angle A.

Next, the signal induced in the detection element is determined by determining the relationship between the current-carrying area of the connection conductor 13, the detection element installed at an arbitrary position within the current-carrying area, and the arrangement of the plurality of connection conductors 13.

However, the number of connecting conductors 13 is generally about 6 to 120, and this configuration changes depending on the design of the brushless exciter.

On the other hand, by creating an energization diagram, the relationship between the arrangement of the connection conductor 13 and the detection element can be determined.

FIG. 5 shows an example of a current flow diagram.

The vertical axis of the figure represents the arrangement angle of each conductor 13, and the horizontal axis represents the rotation angle.

Any one point on the horizontal axis represents one time, and the vertical axis represents the state of the rotor at that moment.

The part indicated by the opening of each phase conductor 13 represents the current-carrying region on the + side of the AC, and the part indicated by the eye represents the current-carrying area on the one side of the AC.

In other words, it shows the spatial and temporal relationships of each conductor 13.

Note that the reference point 0° for the arrangement angle of the connecting conductors 13 is fixed structurally, and as for the rotation angle, the power factor of the AC exciter is a nearly constant value due to the rectifier circuit system, so the armature coil The energized field pole and armature coil positions are determined.

Figure 5 shows an AC frequency of 300 l, rectifier circuit 1S10P-
The configuration is 6A, the number of connected conductors is 10 for each phase of U, V, W, and U, U, V, V, W, W, U, U...
. . . is a partially enlarged view of an energization diagram in the case of a phase-sequential belt order.

Horizontal lines ``■'' and ``■■'' shown in the figure indicate the positions of a pair of detection elements among at least one pair of detection elements disposed on the fixed part as an embodiment of the present invention.

The detection element, such as an I-type detection coil, detects the magnetic flux caused by the current of the rotating part conductors facing each other with a certain air gap, and induces a voltage.

The pair of detection elements may be placed at any position, but in FIG. 5 they are separated by 72 degrees.

In FIG. 5, the detection coil can detect conductor drift at the intersections of the detection element position lines (1) and (1) and the energized area lines of each phase conductor 13.

However, since the magnetic flux caused by the current is actually detected, it is affected by the current in each conductor near the detection element position line, so it is impossible to detect an abnormality by calculating the induced voltage due to each conductor using a single detection element. Very difficult.

However, as in this invention, in the case of the example shown in Figure 5, 72°
By installing separate detection elements at intervals of

If you examine the detection element position lines of (1) and (2), you will find that they follow exactly the same energization phenomenon, only the display number of the conductor changes over time.

That is, at the same time that position ■ and conductor ■ intersect, position line II and conductor ■3 intersect, and position line
At the same time when the conductor (2) and the conductor (2) intersect, the position line II and the conductor (2) intersect.

That is, just by changing the conductor number, the energization phenomenon, that is, the induced voltage of the detection element continuously detects the same waveform.

If the signals of this pair of detection elements are combined in reverse connection and canceled, it will theoretically be the same as there being no signal.

However, if there is an abnormality in the conductor (1) and no current flows, then the induced voltage waveform of the detection element at the (2) position will be significantly different from the normal one.

The induced voltage waveform of the II color position detection element measured at the same time remains normal, and the difference signal of the pair of detection elements (■, ■■) naturally differs significantly from the normal situation.

It should be noted that even if the 72° interval is slightly off, since detection is performed using magnetic flux, only a minute signal will appear as noise, but there is no problem compared to an excessive signal in the event of an abnormality, and it can be easily detected.

The spacing between a pair of detection elements varies depending on the conductor configuration, so
The necessary number of detection elements may be selected and arranged so that all conductors can be compared as described above.

After all, no matter how the connecting conductors change, even if they are not arranged at equal pitches, as long as they are regularly distributed and arranged, abnormal signals can be detected by using a composite signal by elucidating the energization phenomenon.

In FIG. 5, the distance between the pair of detection elements is the same wherever the distance is an integral multiple of 72°.

However, this interval varies depending on the number and arrangement of connected conductors.

FIG. 6 shows a diagram of the circuit configuration principle of this invention.

The connecting conductor 13 is fixed to the rotor shaft 18 and rotated.

A pair of detection elements 22 installed on the fixed side are connected to the connection conductor 1.
3 generates a signal when energized, and this pair of detection elements 22 are connected in a direction to cancel each other's signals, and are connected to an abnormal signal detection circuit 23 which is a voltage discrimination circuit.

The detection circuit 23 may be a simple circuit, for example, one that operates the alarm circuit 24 by a signal voltage of a certain value or more.

A circuit diagram according to an embodiment of this invention is shown in FIG.

The presence or absence of the signal from the rain detection element 22 is first checked by the signal detection circuit 25, and a composite signal obtained by synthesizing the peak values of the signals from the rain detection element 22 is input to the dead band circuit 26.

In this circuit 26, the rise signal is removed by a signal proportional to the field current from the field current signal circuit 29 of the AC exciter, and only the overvoltage signal that occurs during an abnormality is sent to the detection circuit 23 and alarm circuit 24. It will be done.

Note that, as shown in FIG. 2, the output from the rectifier circuit is connected to a load with inductance.

In this case, the connection conductor 13
The change in the current flowing through the circuit is delayed.

In order to compensate for this, by inserting a delay circuit such as a timer into the signal from the field current signal circuit 29, the dead zone circuit 26 can operate more reliably.

In addition, although the above embodiment describes the case of detecting an abnormality in the connecting conductor that carries alternating current between the brushless exciter and the rotary rectifier, the present invention is not limited to this, and for example, detecting an abnormality in the diode circuit connecting conductor 28 in FIG. It can also be applied to obtain the same effect.

As described above, this invention uses a detection circuit that arranges paired detection elements in combination and discriminates the signal voltage of the detection elements, and can be made with an extremely simple device at low cost. Even if the signal characteristics change due to a change in the number or a change in load, the synthesized signal does not change, but changes significantly in an abnormal state, so that a highly accurate and reliable abnormality detection device can be obtained.

[Brief explanation of the drawing]

Figure 1 is a principle diagram of a brushless exciter for a synchronous machine, Figure 2 is a schematic explanatory diagram of a rotor showing the connection conductor between the armature and rotary rectifier of the AC exciter in Figure 1, and Figure 3 is a diagram of the rotor. Fig. 2 is a diagram showing the relationship between the armature coil and the connecting conductor brought out by the armature coil, Fig. 4 is a cross-sectional front view of the connecting conductor portion of the rotor shown in Fig. 2, and Fig. 5 is an embodiment of this invention. FIG. 4 is an energization diagram of a connecting conductor to which a device according to the invention is applied, FIG. 6 is a diagram showing the principle of a circuit configuration according to this invention, and FIG. 7 is a circuit diagram of a device showing an embodiment of this invention. 4... Rotor, 7... Stator field,
3...Rotating armature, 13...Connection conductor, 18...Rotor shaft, 22...Detection element, 23...Abnormality Signal detection circuit, 24...
...Alarm circuit, 26...Dead band circuit, 29...
...Field current signal circuit. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] a plurality of connecting conductors distributed on the rotating body of the rotor and having parallel connections for connecting the rotating electric machine of the rotor and the rotary rectifier to supply current; at least one pair of detection elements forming a pair of detection elements; The above-mentioned detection device is installed at a location where both of the above-mentioned connection conductors are arranged on the fixed side with a predetermined distance apart from each other, are opposed to the above-mentioned connection conductor with an air gap in between, and generate the same signal upon detection when each of the above-mentioned connection conductors is normally energized. an abnormality signal detection circuit which inputs the detection signals of the pair of detection elements in a mutually canceling connection and outputs a signal when there is a difference between the two detection signals, and a signal from this detection circuit that indicates an abnormality. An abnormality detection device for a rotor connecting conductor, which is equipped with a display circuit and is configured to find the above-mentioned points using a current flow diagram.