JPS6226074B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a non-contact detection device that non-contact detects a plurality of measured quantities on the rotor side of a brushless rotating machine.

Recently, there has been an increasing demand for rotating machines without brushes, including brushless synchronous machines. This is due to a maintenance-free orientation that reduces maintenance and inspections. Detection of various electrical quantities on the rotor side of a brushless synchronous machine, such as the voltage and current of the field circuit, or the temperature of each part, has so far been hardly carried out. In rare cases, a slip ring is temporarily installed and the current is guided to the stationary side using brushes for detection, or a non-contact method is used using a rotating transformer method that uses the rotor side alternating current winding as the primary circuit. was. However, although the former is a brushless machine, it cannot be said to be completely brushless because it uses a brush for detection. Furthermore, since this method is used during tests in factories, the rotor side is operated in a blind state in actual operating conditions. At present, there are no electrical accidents on the rotor side of brushless machines, and there is no practical problem, but in order to improve rotor control performance, it is effective to know information on the rotor side. Therefore, the latter type of rotary transformer is used.This rotary transformer has a rotor side coil that is concentric with the shaft, is attached to the rotor, and is magnetically coupled to a detection element provided on the rotor side. Because it is necessary to detect This increases the axial length of the machine, increases its dimensions, and is often difficult to assemble and install, which increases the cost of the machine and is particularly unsuitable for high-speed rotating machines.

An object of the present invention is to provide a highly reliable non-contact detection device that has a simple and compact structure and can accurately detect a large number of measured quantities on a rotor without contact. do.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 3. A rotor 2 rotating in response to a stator 1 of the alternating current generator receives the output of an alternating current exciter armature winding 3 through a rotary rectifier 4 by DC exciting an alternating current exciter field winding 3 a. A so-called brushless excitation method is used in which the generator field winding 5 is excited with direct current after the current is converted into direct current. FIG. 1 shows a device for non-contact detection of current and voltage in a DC circuit in this system. The rotor 2 includes a voltage detection winding 6 that forms a parallel circuit with the field coil 5 of the DC circuit and is connected via a resistor 6a, and a current detection winding 7 that forms part of the DC circuit. be. These detection windings 6 and 7 are the second
As shown in the drawings and FIG. 3, they are arranged around the circumference of a part of the rotor 2 at approximately the same axial position. And on the stator side, these detection windings 6,
A detection sensor 8 is provided at a position where it can be sequentially magnetically coupled to the sensor 7 during rotation. This sensor 8 has a magnetic circuit 8a
A coil 8b is wound around the coil 8b, and the induced electromotive force due to changes in the amount of magnetic flux is used as the output amount. In addition to these, a position detector 9 that can detect the rotational direction position of the rotor is provided. A signal selection circuit 11 receives the detection signal output from the detection sensor 8, the signal from the position detector 9, and the signal from the switching circuit 10, and selects and outputs only a predetermined signal; and an amplification circuit 12 receives the signal. A signal evaluation circuit 13 is provided for evaluating and displaying the peak value of the output signal.

Next, the operation and effects of the above configuration will be explained.

While the rotor 2 is rotating, the sensor 8 on the stator side is magnetically coupled to each of the detection windings 6 and 7 in sequence, and detects a pulsed signal having a peak value proportional to the respective excitation current. . In the case of the configuration shown in FIGS. 2 and 3, there is only one voltage detection winding 6 and one current detection winding 7 on the circumference of the rotor 2, so the rotor 2 Two types of signals are alternately detected once each during one rotation. The signal selection circuit 11 selects the signal from the position detector 9 and the switching circuit 10.
Depending on the signal from the amplifier 12, one of the two types of signals is selected and sent to the amplifier 12. Figure 4 shows a time chart of this situation. In this figure, the [A] signal is a signal from the detection sensor 8, and a signal A for the voltage detection winding 6 and a signal B for the current detection winding 7 appear alternately.
The [B] signal is a signal from the position detector 9, and is a pulse once per rotation. The signals [C] and [D] are sent to the switching circuit 1 in synchronization with the signal [B] of the position detector 9.
These are rectangular wave discrimination signals a and b whose period is divided into two by the signal from 0, C is a signal for discriminating the signal A for the voltage detection winding, and [D] is the signal for the current detection winding. This is a signal that distinguishes signal ro. The signal selection circuit 11 calculates the AND of the [A] signal and the [C] or [D] signal, and outputs the output signal [E].
Or roll [F].

In this way, the signal selection circuit 11 performs the above signal processing to select only the same signals,
The signal is sent to the amplifier 12. The signal evaluation circuit 13 also has a so-called detected value display function that creates and displays an analog signal or digital signal proportional to the so-called peak value from the negative peak value to the positive peak value or from 0 to the peak value of the input signal. are doing. Therefore, by interlocking with the switching circuit 10, the voltage or current of the field circuit on the rotor 2 can be measured.

It has been confirmed through experiments that the peak value of the pulsed signal detected by the sensor 8 is approximately proportional to the current flowing through the detection windings 6 and 7 on the rotor 2 side (however, the rotation speed is constant), so if the peak value of the signal is measured, there is no problem in detecting the voltage and current of the field circuit.

Next, another embodiment will be described with reference to FIG. This measures the temperature of each part of the rotor 2, and the output of the thermocouple 14, which is a detection element, is
After being powered up and impedance matched by a DC amplifier 15 provided on the rotor 2, it is connected to a temperature detection winding 16 and magnetically coupled to the sensor 8. The subsequent signal processing is the same as in the case of FIG. 1, so its explanation will be omitted.

In this way, the temperature of each part on the rotor 2 can be easily detected without contact. Note that the present invention is not limited to the embodiments described above and shown in the drawings, such as the number of signals to be detected may be any number, and a Hall generator may be used for the sensor 8.
Of course, various modifications can be made without changing the gist of the invention.

As explained above, according to the present invention, arbitrary signals are obtained from the plurality of signals obtained by the sensor 8 on the stator side which is magnetically coupled to the plurality of detection windings 6, 7, 16 on the rotor 2. Since only specific signals are discriminated and detected, a large number of measured quantities on the rotor 2 can be detected accurately with a simple and compact structure and in a non-contact manner. A highly reliable non-contact detection device can be obtained. Therefore, it is useful for early prediction and monitoring of abnormalities on the rotor 2, increases the reliability of the rotating electric machine, and since it is non-contact, maintenance and inspection are not required, and it can be applied regardless of the atmospheric environment. It has great practical effects.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing one embodiment of the non-contact detection device of the present invention, Fig. 2 is an elevational view showing the detection part thereof, Fig. 3 is a side view of Fig. 2, and Fig. 4 is its implementation. FIG. 5 is an explanatory diagram showing signal waveforms of each part of the example, and FIG. 5 is a block diagram showing main parts of another embodiment. 2...Rotor, 6, 7, 16...Detection winding,
8...Sensor, 9...Position detector, 10...Switching circuit, 11...Signal selection circuit, 12...Amplification circuit, 13...Signal evaluation circuit.

Claims (1)

[Claims] 1. In a device that non-contact detects multiple measured quantities on a rotor, a detection winding corresponding to each measured quantity is provided on the circumference of the rotor, and a detection winding corresponding to each measured quantity is provided on the stator side as the rotor rotates. , a sensor capable of sequentially magnetically coupling with the detection windings to detect the quantities to be measured is provided, and a position detector capable of detecting the position of the rotor is separately provided, and the signal from the position detector is used to detect the position of the rotor. , a non-contact device characterized by comprising a device that can distinguish and detect only any specific signal among the rotor-side signals detected by the sensor, and a signal evaluation device operated by the signal. Detection device.