RU1780055C - Method and apparatus for spotting turn-to-turn short circuits in electrical windings - Google Patents

Abstract

Usage: when controlling the windings of electrical machines and devices. SUMMARY OF THE INVENTION: the device comprises an oscillating circuit 1, an oscillator amplifier 3, an output amplifier 4, an indication device 5, a connection device 6, a quality factor 7. 2-6-7-3-4-5. 2 s.p. and 1 s.p. of f-ly, 3 ill.

Description

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Figure 1 The invention relates to electrical engineering, in particular to devices for determining damage to electrical windings, and can be used to monitor the health of windings of electrical machines and apparatuses. The purpose of the invention is to increase the sensitivity and simplify the device. Figure 1 shows a structural diagram of a device that implements the proposed method; Figs. 2 and 3 show a structural diagram and a structurally-principal diagram of a variant of the device that implements its proposed method. Figure 1-3 shows: 1 - oscillatory circuit, including capacitors and inductance of the tested windings, 2 tested windings, 3 - the oscillator amplifier, 4 - output amplifier, 5 - indicating device, b - winding switching (switching) device and frequency-setting capacitors, 7-converter of negative resistance, Q factor of the tested windings (oscillatory circuit), 8 - converter and oscillator amplifier, 9, 10 input capacitance of the converter, 11, 12 - feedback resistors, 13, 14 - mixing resistors. The method including the operation of multiplying the quality factor of the circuit with the tested winding 2 is implemented using the negative resistance converter 7 (Fig. 1). When connecting the converter 7 with the inductance of the winding 2, the quality factor of the circuit 1 Q 4RoQp / (4Ro-ap / о), where RO is the feedback resistance 11 (Fig. 3); QP - working quality factor of the circuit without multiplication; p is the wave impedance of the circuit with the tested winding. The multiplication of the quality factor of the circuit is achieved under the condition 4Ro QpXL. In the device (Fig. 1) that implements the method, the tested windings 2 are connected to the negative resistance converter 7 and, together with the input capacitors of the converter, form a frequency-defining oscillatory circuit for the oscillator amplifier 3 with a Q factor, which increases the sensitivity of the oscillator-to-coil closure m, from the oscillator 3, the signal through the output amplifier 4 is supplied to the device 5 indicating the mode of the oscillator and switching (switching) of the windings 2 in the circuit 1. The embodiment of the converter negative resistance 7 is shown in Fig. 3, in this embodiment of the device the converter is aligned with the oscillator 3, which simplifies the device. The Q factor can be put into auto-generation mode provided. The negative converter includes an amplifier 8, input capacitances 9, 10, feedback resistors 11, 12, bias eesistors 13, 14. The windings 2 are connected to the converter via a switch 6 and together with the input capacitors 9, 10 form an oscillatory circuit. All elements as a whole form the quality factor of the tested sweeps. To check for the presence of round faults in the windings, for example, three-phase ones, by connecting the windings 2 in series to the input of the Q factor and adjusting the under-section resistor 11, a converter generation mode is created and the indicator giving the maximum generation amplitude is determined from indicator 5. If there is such a winding, then calibration of the device is performed on this winding. Then, a breakdown in generation or a noticeable decrease in readings when another winding is connected will indicate the presence of coil faults in the connected winding. If the indicator readings do not change when other windings are connected, then these windings have no defects, If there are coil faults in all windings (which is small probably) it will be difficult to obtain a lasing mode within the variation of the tuning resistor. The capabilities of the proposed method and device allow checking electrical machines and apparatuses without disassembling. The proposed method and device for its implementation allows to increase the sensitivity to coil closures with the comparative simplicity of the device. Formula and Acquisition 1. A method for detecting 3avibcrank turns in electric windings, according to which the mode of operation of the autos generator is measured, is included in the oscillatory canture of the oscillator controlled

winding, and the presence of windings is judged by a change in the mode of operation of the oscillator, characterized in that, in order to increase sensitivity, an operation is performed to multiply the quality factor of the controlled winding.

2. A device for determining winding short circuits in electrical windings, comprising a self-oscillator with an oscillatory circuit, an amplifier, a connecting device, an indicator, a test object and an oscillatory circuit connected to the first

and the second outputs of the connection device, respectively, the output of the oscillator is connected through an amplifier to an indicator, characterized in that that, in order to increase the sensitivity, a Q-factor is introduced into it, the output of which is connected to the input of the oscillator, and the input is the third output of the connection device.

3. The device according to claim 2, characterized in that, in order to simplify the device, the oscillator is combined with a quality factor.

FIG.