KR102544604B1 - Method for detection of fault of synchronous machine - Google Patents

Abstract

A method for diagnosing a synchronous machine failure is disclosed. The method for diagnosing failure of the synchronous machine includes measuring an AC voltage and an AC current applied to a rotor of the synchronous machine, calculating an equivalent impedance using the measured AC voltage and the AC current, and comparing the equivalent impedance with a reference impedance. and determining whether or not an error has occurred in the synchronizer according to a comparison result between the equivalent impedance and the reference impedance.

Description

Synchronous machine failure diagnosis method and apparatus {METHOD FOR DETECTION OF FAULT OF SYNCHRONOUS MACHINE}

It relates to a method and apparatus for diagnosing synchronous machine failure.

A synchronous machine is an alternating current electric machine that rotates at synchronous speed in normal operation, and can operate as a generator or as a motor depending on design or control. Specifically, the synchronous machine has a stator and a rotor that can rotate inside the stator. When the rotor is rotated at synchronous speed using a turbine, three-phase voltage is generated in the three-phase windings of the stator, and the synchronous machine operates as a generator. When a three-phase voltage is applied to the three-phase windings of the stator, a rotating magnetic field rotating at a constant synchronous speed is generated inside the stator, and the rotor rotates in response to this, so that the synchronous machine operates as a motor. The insulation formed in the turns of the field winding is subject to mechanical stress (due to the high-speed rotation of the rotor), electrical stress or thermal stress and is susceptible to deterioration. Also, the damper bar may be damaged by transient currents and high-speed rotation. In addition, in the case of a brushless synchronous machine, a diode of a rectifier may be short-circuited or open due to mechanical, electrical, or thermal stress caused by high-speed rotation of a rotor. Such defects cause deterioration in performance and shortened lifespan of the synchronous machine. Therefore, it is necessary to diagnose these defects at an early stage to maintain and manage the synchronizer. As a method for diagnosing such a defect, there are an offline test performed after the operation of the synchronous machine is stopped by cutting off the power applied to the synchronous machine, and an online test performed without stopping the operation of the synchronous machine. Offline tests include visual inspection, pole drop test, recurrent surge oscillography (RSO), and the like, and online tests include a method using a magnetic flux sensor on the surface of the stator. However, these methods have problems in that the synchronizer must be disassembled, cannot be applied depending on the design method or type of the synchronizer, or accuracy and reliability are relatively low. In addition, there are many cases where it is impossible to measure whether a fault such as a field winding short circuit has occurred depending on the operating state of the synchronous machine, so it is difficult to accurately diagnose whether or not a synchronous machine fault has occurred with only the above-described method.

It is a task to solve the problem of providing a method and device for diagnosing synchronous machine failures that can diagnose defects in the field winding, damper bar or rectifier diode of the synchronous machine without disassembly or before disassembly of the synchronous machine with convenient, easy and high diagnostic sensitivity and reliability. do.

In order to solve the above problems, a synchronous machine failure diagnosis method and apparatus are provided.

A method for diagnosing a synchronous machine failure includes measuring an AC voltage and an AC current applied to a rotor of a synchronous machine, calculating an equivalent impedance using the measured AC voltage and AC current, and comparing the equivalent impedance with a reference impedance. and determining whether or not an error has occurred in the synchronizer according to a comparison result between the equivalent impedance and the reference impedance.

Determining whether or not the synchronous machine has an abnormality according to the comparison result between the equivalent impedance and the reference impedance includes determining that damage has occurred to a damper bar provided in the rotor when the equivalent impedance is greater than the reference impedance Step and When the equivalent impedance is less than the reference impedance, at least one of determining that a short circuit has occurred in the field winding provided in the rotor may be included.

The synchronizer may include a synchronizer of a different excitation method or a self excitation method.

A method for diagnosing a failure of a synchronous machine including an excitation stator and a rotor, wherein the rotor includes an excitation rotor, a rectification unit connected to the excitation unit and including at least one diode, and a synchronous rotor connected to the rectification unit, A step of applying an alternating current to the stator of the excitation part, comparing the obtained waveform of voltage or current with a reference waveform to determine whether distortion has occurred in the waveform of the voltage or current, or measuring the field winding equivalent impedance of the stator of the excitation part, , comparing this with the impedance in a steady state, and determining whether distortion has occurred in the voltage or current waveform based on the comparison result.

The method for diagnosing a synchronous machine failure may further include rotating the rotor at a predetermined angle according to a user's manipulation or a predefined setting, and then stopping the rotor.

The synchronous machine failure diagnosis apparatus obtains information on an AC voltage and an AC current applied to a storage unit storing a reference impedance and a rotor of the synchronous machine, calculates an equivalent impedance using the AC voltage and the AC current, and It may include a processor that compares the equivalent impedance with a reference impedance and determines whether or not an error has occurred in the synchronizer according to a comparison result between the equivalent impedance and the reference impedance.

The processor determines that damage has occurred to the damper bar provided in the rotor when the equivalent impedance is greater than the reference impedance, or shorts the field winding provided in the rotor when the equivalent impedance is less than the reference impedance. It can be judged that this has occurred.

The synchronizer may include a synchronizer of a different excitation method or a self excitation method.

An apparatus for diagnosing failure of a synchronous machine includes a processor for diagnosing whether a synchronous machine is out of order and an output unit for outputting a diagnosis result of the processor, wherein the synchronous machine includes a stator and a rotor of an excitation part, and the rotor includes a rotor of an excitation part and the excitation part. A rectifier connected to and including at least one diode, and a synchronous rotor connected to the rectifier, wherein the processor determines whether a waveform of a voltage or current applied to the exciter stator is distorted, and the voltage or When distortion occurs in the current waveform, it may be determined that the at least one diode is open.

The processor obtains a voltage or current waveform applied to the synchronous unit rotor, and compares the obtained voltage or current waveform with a reference waveform to determine whether distortion has occurred in the voltage or current waveform, or the excitation unit It is possible to measure the equivalent impedance of the field winding of the stator, compare it with the impedance in a normal state, and determine whether distortion has occurred in the voltage or current waveform based on the comparison result.

The processor may rotate the rotor at a predetermined angle and then stop the rotor according to a user's manipulation or a predefined setting.

According to the above-described synchronous machine failure diagnosis method and device, the effect of being able to diagnose defects in the field winding, damper bar, or rectifier diode of the synchronous machine with convenience, ease, and high diagnostic sensitivity and reliability without or before disassembly of the synchronous machine can be obtained. can

According to the above-described method and apparatus for diagnosing failure of a synchronous machine, it is possible to obtain an effect of diagnosing by off-line whether a rectifier diode of a brushless synchronous machine is open without performing costly and time-consuming disassembly of the synchronous machine.

According to the above-described synchronous machine failure diagnosis method and apparatus, there is an effect of being able to easily and accurately diagnose whether or not the damper bar is open, which was impossible except for visual inspection.

According to the above-described synchronous machine failure diagnosis method and apparatus, it is possible to easily diagnose short circuit of the synchronous machine field winding or open damper bar with higher diagnostic sensitivity and reliability than visual inspection, shared voltage test, or repeated surge oscillogram method. advantage can be obtained.

According to the above-described synchronous machine failure diagnosis method and apparatus, it is possible to diagnose whether a field winding is short-circuited, whether a damper bar is broken, or whether a diode is open can be diagnosed off-line simply and at low cost, thereby increasing the convenience and economy of use and maintenance of the synchronous machine. The effect of being able to promote and improve can also be obtained.

1 is a schematic diagram of one embodiment of a synchronizer and diagnostic device.
FIG. 2 is a diagram for explaining an embodiment of a process of diagnosing a synchroniser of a different excitation method and whether or not it is out of order.
3 is a diagram showing an example of an equivalent circuit in the case of applying an AC voltage to a synchronous rotor through a slip ring.
4 is a circuit diagram of an embodiment of a self-excited synchronizer.
5 is a flow chart of one embodiment of a synchronizer diagnosis method.
6 is a flowchart of another embodiment of a synchronizer diagnosis method.

In the entire specification below, the same reference numerals refer to the same components unless otherwise specified. A term with an added 'unit' used below may be implemented in software or hardware, and depending on an embodiment, one 'unit' is implemented as one physical or logical component, or a plurality of 'units' are implemented as one unit. It is possible to implement a physical or logical component, or one 'unit' to implement a plurality of physical or logical components.

When a part is said to be 'connected' to another part throughout the specification, it may mean a physical connection or an electrical connection depending on the part and the other part. In addition, when a part 'includes' another part, this does not exclude another part other than the other part unless otherwise stated, and another part may be further included according to the designer's choice. means there is

Terms such as 'first' or 'second' are used to distinguish one part from another, and do not mean sequential expressions unless otherwise specified. In addition, singular expressions may include plural expressions, unless there is a clear exception from the context.

Hereinafter, various embodiments of a synchronous machine and a synchronous machine failure diagnosis apparatus will be described with reference to FIGS. 1 to 4 .

1 is a schematic diagram of one embodiment of a synchronizer and diagnostic device.

Synchronizer 100 is a device that can be operated as a generator or electric motor, for example, to generate electric power by rotating a rotor (120 in FIG. 2, 150 in FIG. 4, etc.) through external power (eg, a turbine, etc.) And / or by applying a three-phase voltage to the windings (for example, three-phase windings (111A, 111B of FIG. 2)) of the stator (110 in FIG. 2, 140 in FIG. 4, etc.) to generate a rotating magnetic field, the rotor 120, 150) is a device that can rotate. The synchronizer 100 may include a brush synchronizer (other exciter synchronizer) or may include a brushless synchronizer (self exciter synchronizer) according to embodiments. In addition, if necessary, the synchronous machine 100 may be electrically connected to the power source 90 to receive electric energy necessary for generating magnetic flux. In this case, the electrical energy may be supplied, for example, to the windings 111A and 111B or 122 of FIG. 2 of the stators 110 and 140 or the rotors 120 and 150 .

A sensor 80 may be further installed in the synchronizer 100 . The sensor 80 may sense and collect information about the synchronizer 100 and may transmit the collected information to the diagnosis device 200 by being communicatively connected to the diagnosis device 200 by wire or wirelessly. Synchronizer 100 may include one or more sensors 80 depending on the embodiment. According to an embodiment, each sensor 80 is configured to properly measure a value to be measured (eg, characteristics of an electrical signal input to the synchronizer 100, such as applied voltage or current). ) may be installed inside or outside the Information obtained by the sensor 80 may be transmitted to the diagnostic device 200 in the form of an electrical signal.

The diagnosis device 200 may receive one or more pieces of information transmitted from the sensor 80 and determine whether or not an abnormality of the synchronizer 100 has occurred (ie, whether a failure or damage has occurred) based on this. For example, the diagnosis device 200 determines whether the field winding 122 is short-circuited based on the received information, diagnoses whether the damper bar (124 in FIG. 2) is open, and/or the rectifier (see FIG. 4). 152), whether one or more diodes (152A to 152F in FIG. 4) are open or not can be determined.

According to an embodiment, the diagnosis apparatus 200 may include a processor 210, a storage unit 220, and an output unit 230 as shown in FIG. 1 . In addition, if necessary, the diagnostic device 200 may include an input unit (not shown) capable of receiving commands or data according to a user's manipulation or predefined settings, or another external terminal device (not shown, for example, a computer device). It is also possible to further include a communication unit (not shown) for transmitting a command or data to a terminal device by communicating with a smartphone or the like) or receiving a command or data from the terminal device.

The processor 210 may determine whether or not an error occurs in the synchronizer 100 based on information about the synchronizer 100 received from the sensor 80 . Also, the processor 210 may use data (eg, a reference impedance (Zr) or a reference waveform) stored in the storage unit 220 to determine whether an abnormality has occurred. More specifically, the processor 210 calculates the equivalent impedance (Zeq) for the synchronizer 100 using the applied voltage and current received from the sensor 80 and calculates the equivalent impedance (Zeq) with the reference impedance (Zr). Compare, and if the equivalent impedance (Zeq) and the reference impedance (Zr) are the same or close according to the comparison result, it is determined that no abnormality has occurred, and if the equivalent impedance (Zeq) is greater than the reference impedance (Zr), the synchronous machine 100 It may be implemented to determine that damage has occurred to the damper bar 124 and, conversely, to determine that a short circuit has occurred in the field winding 122 if the equivalent impedance Zeq is smaller than the reference impedance Zr. In addition, the processor 210 compares the waveform of the input voltage (or input current) input to the synchronizer 100 with the reference waveform pre-stored in the storage 220, and according to the difference between the waveform of the input voltage and the waveform of the reference voltage. It may be designed to determine that a short has occurred across diodes 152A-152F. The processor 210 may control the power supply 80 or the synchronizer 100 as needed. For example, the processor 210 transfers a control signal to the power supply 80 directly or to a switch element (or switch device) between the power supply 80 and the synchronizer 100 so that power of an arbitrary or specific waveform is synchronized ( 100), or the rotors 120 and 150 of the synchronous machine 100 may be controlled to start or stop rotation.

According to an embodiment, the processor 210 may include, for example, a central processing unit (CPU), a micro controller unit (MCU), a micro processor (Micom), an application processor (AP), , Application Processor), electronic control unit (ECU), and/or other electronic devices capable of generating various arithmetic processing and control signals. These devices, for example, may be implemented using one or more semiconductor chips, etc., and perform the above-described operation by driving a program (which may be referred to as an app, application, or software) stored in the storage unit 220. It may have been designed to do so.

The storage unit 220 may temporarily or non-temporarily store data necessary for the operation of the processor 210 (for example, a reference impedance (Zr) or a reference waveform) or at least one program. Here, the application stored in the storage unit 220 may be directly written or modified by a designer and stored in the storage unit 220, or may be provided, installed, and updated from the outside through a memory device, etc., and/or Alternatively, it may be obtained or updated through an electronic software distribution network accessible through a wired or wireless communication network. The storage unit 220 may include, for example, at least one of a main memory device and an auxiliary memory device, and these may be implemented using semiconductors or magnetic disks.

The output unit 230 may visually or audibly output the processing result of the processor 210 to the outside. For example, the output unit 230 may output the diagnosis result according to the process of the processor 210 manually according to a user's manipulation or automatically according to a predefined setting. The diagnosis result may include, for example, whether the field winding 122, the damper bar 124, and/or the diodes 152A to 152F are damaged. Depending on the embodiment, the output unit 230 may be integrally provided with the diagnostic device 200 or may be physically separated. The output unit 230 may include, for example, a display, a printer device, a speaker device, an image output terminal, a data input/output terminal, and/or a communication module, but is not limited thereto.

The diagnostic device 100 described above may be implemented singly or in combination with one or more devices capable of arithmetic processing. For example, the diagnosis device 100 may be a desktop computer, a laptop computer, a smart phone, a tablet PC, a smart watch, a navigation device, a portable game machine, a head mounted display (HMD) device, a digital television, a set top box, It may include artificial intelligence sound reproduction devices (artificial intelligence speakers), manned or unmanned vehicles (cars, buses, vehicles such as two-wheeled vehicles, robot vacuum cleaners, etc.), manned or unmanned aerial vehicles (drones, etc.), household or industrial robots or industrial machines, etc. However, it is not limited thereto, and in addition to these, a designer or user may include various information processing devices that can be considered according to circumstances or conditions.

Hereinafter, with reference to FIGS. 2 and 3, an embodiment of the synchronizer 101 of the other excitation type and a process of diagnosing the same will be described.

2 is a diagram for explaining an embodiment of a synchronous machine of the other excitation type and a process of diagnosing its failure, and FIG. 3 is an equivalent circuit in the case of applying an AC voltage to a synchronous machine rotor through a slip ring. It is a drawing showing an example.

Referring to FIG. 2 , the synchronizer 101 according to an embodiment may include a synchronizer of a different excitation type. The synchroniser 101 of the other excitation method may include, for example, a salient pole rotor 120 . For convenience of description, a process for diagnosing a failure of the synchronous machine 101 will be described based on the synchronous machine 101 having the salient pole rotor 120, but the type of the rotor 120 of the synchronous machine 101 is limited to this. it is not going to be As another example, the rotor 120 may include a cylindrical rotor, and the method for diagnosing the synchronous machine 101 described below may be applied to a synchronous machine having a cylindrical rotor in the same way or through some modification. . More specifically, the synchronous machine 101 includes a stator 110 having a space formed therein, stator windings 111A and 111B disposed in substantially parallel and isolated from each other at a predetermined angle or distance from the stator 110, and windings corresponding to each other. current flows in different directions), the rotor 120 provided to be rotatable around the rotation shaft 129 in the space inside the stator 110, and installed on the rotor 120 to generate DC magnetic flux It is fixed and installed around the field winding 122 and the rotating shaft 129 of the rotor 120, and is electrically connected to the field winding 122 of the rotor 120 and applied to the synchronous machine 101 from the power source 90 supply current to the field winding 122 or receive the current passing through the field winding 122, and the slip ring 127 generally formed in a spiral shape, and the slip ring 127 and the slip ring 127 according to the rotation of the slip ring 127 Electrically connected or disconnected, the current applied from the power source 90 through the cable 91A is provided to the slip ring 127, or the current transferred from the field winding 122 to the slip ring 127 is transferred to another cable 91B. ), etc., but may include brushes 128A and 128B fixed to the stator 110 as needed. As shown in FIG. 2, the rotor 120 may be provided with one or two or more (for example, four) poles 121, all or part of each pole 121. Each of the field windings 122 may be wound around dozens to hundreds of turns. In addition, a pole head 123 may be formed at an end of the pole 121 toward the stator 110, and a damper bar 124, a damper bar, a damper winding bar ( The damper winding bar)) may be buried or exposed and arranged in one or more rows. The damper bar 124 is installed outside the rotor 120 and enables the synchronous machine 101 to operate as an electric motor or stabilizes the operation of the synchronous machine 101. No voltage is applied to the damper bar 124, and current flows with the induced voltage instead. The damper bar 124 may be omitted according to embodiments. The synchronous machine 101 operates as an electric motor by rotating the rotor 120 by magnetic flux generated by current flowing through the stator windings 111A and 111B, or rotates the stator winding by rotating the rotor 120 by a turbine or the like. As current flows through (111A, 111B), it can operate as a generator.

Referring to FIG. 3, the equivalent circuit 130 for the above-described synchronous machine 101 is the resistance of the anode 131 to which voltage is applied and current is supplied, and the field winding 122 connected to the anode 131. A first resistor 132 representing , a first inductor 133 connected in series with the first resistor 132 and representing the leakage inductance of the field winding 122 , and a main magnetic flux connected in series with the first inductor 133 A second inductor 134 representing the magnetizing inductance of the path, a second resistor 135 connected in parallel with the second inductor 134 and representing the resistance of the damper bar, and a second resistor 135 connected in series to the second resistor 135 and A third inductor 136 connected in parallel with the inductor 134 and representing leakage inductance of the damper bar may be included. Here, the voltage applied to the anode 131 may be larger or smaller than the capacity of the synchronous machine 101 . For example, the voltage applied to the anode 131 may include a voltage of several to several tens of volts (V) capable of appropriately obtaining resolutions of voltage and current. In addition, the equivalent circuit 130 of the synchronous machine 101 can include a third resistor 137 and a fourth inductor 138 that can be set to a short circuit state 139, the third resistor 137 is 2 shows the resistance of the loop connected in parallel with the inductor 134, the second resistor 135 and the third inductor 136 and shorted in the field winding 122, and the fourth inductor 138 is the third resistor 137 It is connected in series with the second inductor 134, the second resistor 135 and the third inductor 136 in parallel, and means the inductance of the loop shorted in the field winding 122. The second inductor 134 , the third inductor 136 and the fourth inductor 138 are connected to the cathode 140 . In this case, if the voltage and current applied to the anode 131 are measured, the equivalent impedance Zeq of the equivalent circuit 130 with respect to the synchronous machine 101 can be calculated.

If an inter-turn short circuit occurs in the field winding 122, the resistance value of the first resistor 132, the inductance of the first inductor 133, and the inductance of the second resistor 134 decrease because the number of turns decreases. On the other hand, when there is an inter-turn defect, relatively small impedances by the third resistor 137 and the fourth inductor 138 are connected in parallel so that the equivalent impedance Zeq for the equivalent circuit 130 is relatively will decrease In other words, the equivalent impedance Zeq when a short circuit exists in the field winding 122 is the equivalent impedance Zeq when there is no short circuit in the field winding 122 (ie, the equivalent impedance Zeq in a steady state, or less than the reference impedance Zr). Therefore, the applied voltage and current applied to the synchronous machine 101 are measured, based on this, the equivalent impedance (Zeq) corresponding to the synchronous machine 101 is calculated, and the standard calculated experimentally or theoretically by the designer or user Compared to the impedance Zr, if the calculated equivalent impedance Zeq is relatively smaller than the reference impedance Zr, it can be determined that a turn-to-turn short circuit has occurred in the field winding 122.

Conversely, when all or part of the damper bar 124 is opened, the resistance value of the second resistor 135 and the inductance of the third inductor 136 relatively increase, but the other resistors 132, 134, and 137 and The values of the inductors 133, 134, and 138 hardly change and generally maintain their original values. Accordingly, the equivalent impedance Zeq of the equivalent circuit 130 with respect to the synchronous machine 101 is relatively increased. Therefore, as described above, the applied voltage and current applied to the synchronous machine 101 are measured, and based on this, the equivalent impedance (Zeq) corresponding to the synchronous machine 101 is calculated, and this is calculated when the synchronous machine 101 is in a steady state. If the calculated equivalent impedance Zeq is relatively greater than the reference impedance Zr as a result of the comparison, it may be determined that the damper bar 124 has been opened.

As described above, each part of the rotor 120, for example, the field winding 122 and / or the damper bar 124 using the equivalent impedance (Zeq) and the reference impedance (Zr) for the synchronous machine 101 It is possible to determine whether there is a malfunction. The above-described measurement of the applied voltage or applied current may be performed by the sensor 80, calculation of the equivalent impedance (Zeq) of the synchronous device 101, and comparison between the calculated equivalent impedance (Zeq) and the reference impedance (Zr). And, determination of normality according to comparison or determination of damaged components, for example, the field winding 122 and/or the damper bar 124, may be performed by the processor 200. The reference impedance Zr may be stored in the storage unit 210 prior to or during the determination process.

Since the above method induces a relatively high voltage in the shorted field loop, it is possible to measure normality with high sensitivity compared to the conventional method. In addition to the above-mentioned equivalent impedance (Zeq), various information such as the size and phase of current or impedance, active power, reactive power, or induced voltage of the synchronous stator 110 are employed to generate the synchronous machine through the same or partially modified process as the above method. It becomes possible to diagnose whether or not 101 is out of order.

Referring to FIG. 4, an embodiment of a self-excited synchronous machine 102 and a process of diagnosing whether or not there is a failure thereof will be described.

4 is a circuit diagram of an embodiment of a self-excited synchronizer.

Referring to FIG. 4 , the synchronizer 102 according to an embodiment may include a self-excitation synchronizer. The self-excitation synchronous machine 102 is a synchronous machine provided to supply a DC voltage through an exciter 140 connected to a shaft of the self-excited synchronous machine 102 without brushes 128A and 128B. Specifically, the self-excitation synchronous device 120 may include an excitation unit 140, an excitor, a rectifying unit 150, and a synchronization unit 160. The excitation unit 140 is provided to supply DC voltage to the synchronous unit 160, and a three-phase current (for example, three-phase low current) is applied and an excitation stator (141, exciter stator) that generates a magnetic field according to the applied current. (field), and a three-phase AC voltage is induced by a magnetic field generated by the exciter stator 141, and an exciter rotor (142, exciter rotor (armature)) provided to rotate around a predetermined axis. . The rectifier 150 may receive the AC voltage induced by the excitation rotor 142 and convert the received AC voltage into DC power to transmit to the synchronous unit 160 . The rectifying unit 150 may rotate about the same axis as the female rotor 142 . The rectifier 150 may include a three-phase full-wave rectifier circuit having a plurality of diodes, for example, six diodes 150A to 150F. The synchronous unit 160 receives DC voltage from the rectifying unit 150, and the synchronous unit rotor 161 rotates around the same axis together with the excitation rotor 142 and the rectifying unit 150. , It may include a synchronous stator (162, machine stator (armature)) disposed outside the synchronous rotor 161 and generating three-phase current according to the rotation of the synchronous rotor 161. The excitation rotor 142, the rectifier 150, and the synchronous rotor 161 may be included in one rotor 170, and in this case, they may be physically interconnected. The female stator 141 and the synchronous stator 162 may be fixed without rotation.

Meanwhile, when the distorted waveform voltage or current C9 is applied to the field winding 161A of the synchronous rotor 161, the input voltage or current of the excitation stator 141 is also distorted. Therefore, by measuring the voltage or current applied to the field winding 141A of the excitation stator 141, defects in the diodes 150A to 150F may be diagnosed. Specifically, when a problem occurs in at least one diode 150A to 150F and is opened, the 60Hz component of the field voltage of the field winding 161A of the synchronization unit 160 decreases, and the current of the field winding 161A decreases. Since the 60Hz component of is correspondingly reduced, the 60Hz equivalent impedance based on the field winding 141A of the excitation stator 141 increases. Therefore, through the process of measuring the equivalent impedance of the field winding 141A of the excitation stator 141 and comparing it with the impedance in a steady state, it is possible to determine whether or not the input voltage or current to the excitation stator 141 is distorted, Based on this, it is possible to determine whether a problem occurs in the diodes 150A to 150F. Meanwhile, whether or not the waveform is distorted and the degree of distortion is different depending on which diode 150A to 150F is open. Therefore, if the position of the rotor 170, that is, the position of the excitation rotor 142, the rectifier 150, and the synchronous rotor 161 are repeatedly determined to determine whether or not the input voltage or current is distorted, the diode is opened. 150A to 150F exist, and which diode 150A to 150F among the plurality of diodes 150A to 150F is open.

Calculation of the equivalent impedance of the field winding 141A may be performed by the processor 210 described above. Information required for calculating the equivalent impedance of the field winding 141A or information on the voltage or current waveforms C1, C2, and C9 may be measured by at least one sensor 80 and transmitted to the processor 210. there is. Rotation control of the rotor 170 may also be performed by the processor 210 . In this case, when the diagnosis is initiated, the processor 210 directly compares the equivalent impedance and/or the voltage or current waveforms C1, C2, and C9 of the field winding 141A with respect to the rotor 170 in the initial position. After determining whether at least one of the diodes 150A to 150F is open, and sequentially controlling the rotor 170 to rotate at a predetermined angle, the equivalent impedance of the field winding 141A and / or the voltage or current waveform (C1 , C2 and C9 are compared to determine whether at least one of the diodes 150A to 150F is open. Of course, according to embodiments, rotation of the rotor 170 may be performed by a device other than the diagnosis device 200 .

Hereinafter, various embodiments of a method for diagnosing a synchronous machine failure will be described with reference to FIGS. 5 and 6 .

5 is a flow chart of one embodiment of a synchronizer diagnosis method.

As shown in FIG. 5, first, an alternating current voltage is applied to a rotor of a synchronous machine, for example, a synchronous machine of a different excitation type or a self-excitation type synchronous machine through a slip ring (400). The input voltage and current are measured, and based on this, an equivalent impedance (Zeq) for the synchronous machine is calculated (402).

The sequentially calculated equivalent impedance (Zeq) is compared with the previously measured or calculated reference impedance (Zr) in a steady state (404).

If the equivalent impedance (Zeq) is greater than the reference impedance (Zr) (YES in 408), it is determined that damage has occurred to the damper bar (410). As described above, when the damper bar is partially opened, the value of the second resistor and the third inductor of the equivalent circuit increases, but values of other elements are maintained, so the equivalent impedance Zeq increases. Accordingly, if the equivalent impedance Zeq is greater than the reference impedance Zr, it may be determined that the damper bar is damaged.

Conversely, if the equivalent impedance (Zeq) is smaller than the reference impedance (Zr) (No in 408, Yes in 412), it can be determined that a short circuit has occurred in the field winding (414). Specifically, when a short circuit occurs in the field winding, the third resistor and the fourth inductor of the above-described equivalent circuit are connected in parallel to reduce the equivalent impedance (Zeq), and accordingly become smaller than the reference impedance (Zr). Therefore, if the equivalent impedance (Zeq) is smaller than the reference impedance (Zr), it can be determined that the field winding has been damaged.

If the equivalent impedance (Zeq) is equal to or closer than the reference impedance (Zr) (No in 412), it can be determined that the damper bar or field winding is normal (416).

6 is a flowchart of another embodiment of a synchronizer diagnosis method.

As shown in FIG. 6 , a rotor of a synchronizer, for example, a self-excited synchronizer may be stopped at an initial position (420). The rotor may include an excitation rotor, a rectifying rotor, and a synchronous rotor.

Subsequently, an AC voltage may be applied to the excitation stator located outside the excitation rotor (422). When an AC voltage is applied to the excitation stator, a magnetic field is generated by the field winding provided in the excitation stator, and thus a three-phase voltage/current is induced in the winding of the excitation rotor. The induced three-phase voltage/current is transmitted to a rectifying unit including at least one diode, and the rectifying unit rectifies the induced three-phase voltage/current and applies it to the field winding of the synchronous unit rotor.

According to the embodiment, it is determined whether or not the waveform is distorted based on the distortion of the input voltage/input current of the field winding of the excitation stator generated in response to the distortion of the input voltage/input current input to the field winding of the synchronous rotor. may be This may be performed by comparing the 60Hz equivalent impedance based on the field winding of the excitation stator with a predetermined reference impedance (ie, impedance in a state where the diode is not damaged). Specifically, as a result of the comparison, if the equivalent impedance is greater than the reference impedance, it can be determined that distortion of the waveform has occurred.

If it is determined that the distortion of the waveform has occurred (YES in 424), it can be determined that the diode of the rectifier corresponding to the initial position of the rotor is open (426). For example, if the 60Hz equivalent impedance based on the field winding of the excitation stator is greater than the reference impedance, it may be determined that the diode of the rectifier is open. Conversely, when it is determined that no distortion of the waveform has occurred (No in 424), it can be determined that the diode of the rectifier corresponding to the initial position of the rotor is not in an abnormal state.

According to an embodiment, if it is determined whether or not the diode is damaged, the diagnosis procedure may be terminated (Yes in 428). According to another embodiment, the rotor rotates at a certain angle in at least one direction and then stops (428 No and 430), then the above-described AC voltage is applied (422, which can be omitted depending on the embodiment), and waveform distortion is determined. Step 424 and determination of diode damage 426 are sequentially performed in the same manner as described above. The rotor can continuously and repeatedly rotate and stop (428 and 430) according to the user's manual operation or predefined settings. In this case, rotation and stop of the rotor may be repeated until the diagnosis of whether all diodes of the rectifying unit are open is completed.

The synchronous machine failure diagnosis method according to the above-described embodiment may be implemented in the form of a program that can be driven by a computer device. Here, the program may include program commands, data files, and data structures alone or in combination. The program may be designed and manufactured using machine language codes or high-level language codes. The program may be specially designed to implement the above-described method, or may be implemented using various functions or definitions known and usable to those skilled in the art in the field of computer software. Also, here, the computer device may be implemented by including a processor or a memory capable of realizing program functions, and may further include a communication device as needed. In addition, a program for implementing the above-described synchronous machine failure diagnosis method may be recorded in a computer-readable recording medium. A computer-readable recording medium includes, for example, a solid state drive (SSD), semiconductor storage devices such as ROM, RAM, or flash memory, magnetic disk storage media such as hard disks or floppy disks, compact disks or DVDs, etc. It may include at least one type of physical device capable of storing a specific program executed according to a call of a computer, such as an optical recording medium, a magneto-optical recording medium such as a floptical disk, and a magnetic tape.

Although various embodiments of the apparatus and method for diagnosing abnormal synchronous machine failure have been described, the apparatus and method for diagnosing synchronous machine failure are not limited to the above-described embodiments. Various devices or methods that can be implemented by a person skilled in the art by modifying and transforming based on the above-described embodiments may also be examples of the above-described synchronous machine failure diagnosis device and method. For example, the described techniques may be performed in an order different from the methods described, and/or components of the described systems, structures, devices, circuits, etc. may be combined or combined in a different manner than the methods described, or other components or components may be used. An embodiment of the above-described apparatus and method may be substituted or substituted by equivalents.

80: sensor 90: power
100: Synchronizer 101: Synchronizer of other excitation type
102: self-excited synchronous machine 110: stator
120: rotor 121: pole
122: field winding 123: pole head
124: damper bar 127: slim ring
128A, 128B: brush 140: female part
141: female stator 142: female rotor
150: rectification unit 160: synchronization unit
161: synchronous rotor 162: synchronous stator
200: diagnostic device 210: processor
220: storage unit 230: output unit

Claims (12)

Measuring AC voltage and AC current applied to the rotor of the synchronous machine;
calculating an equivalent impedance using the measured AC voltage and AC current;
comparing the equivalent impedance to a reference impedance; and
Determining whether or not an error has occurred in the synchronizer according to a comparison result between the equivalent impedance and the reference impedance;
The step of determining whether or not an error has occurred in the synchronizer according to the comparison result between the equivalent impedance and the reference impedance,
determining that damage has occurred to a damper bar provided in the rotor when the equivalent impedance is greater than the reference impedance; and
Including the step of determining that a short circuit has occurred in the field winding provided in the rotor when the equivalent impedance is smaller than the reference impedance.
A method for diagnosing synchronous machine failures. delete According to claim 1,
The synchronous machine failure diagnosis method comprising a synchronous machine of a different excitation method or a self-excitation synchronous machine. A method for diagnosing a failure of a synchronous machine including an excitation stator and a rotor, wherein the rotor includes an excitation rotor, a rectification unit connected to the excitation unit and including at least one diode, and a synchronous rotor connected to the rectification unit,
(a) applying an alternating current to the excitation stator of the excitation unit;
(b) acquiring a voltage or current waveform applied to the synchronous rotor and comparing the acquired voltage or current waveform with a reference waveform to determine whether distortion has occurred in the voltage or current waveform; and
(c) determining that the at least one diode is open when distortion occurs in the waveform of the voltage or current;
When distortion does not occur in the waveform of the voltage or current, repeating steps (a) to (c) after rotating the rotor at a predetermined angle and then stopping,
A method for diagnosing synchronous machine failures. A method for diagnosing a failure of a synchronous machine including an excitation stator and a rotor, wherein the rotor includes an excitation rotor, a rectification unit connected to the excitation unit and including at least one diode, and a synchronous rotor connected to the rectification unit,
(a) applying an alternating current to the excitation stator of the excitation unit;
(b) measuring the equivalent impedance of the field winding of the excitation stator, comparing the equivalent impedance with the impedance in a steady state, and determining whether a voltage or current waveform is distorted based on the comparison result; and
(c) determining that the at least one diode is open when distortion occurs in the waveform of the voltage or current;
When distortion does not occur in the waveform of the voltage or current, repeating steps (a) to (c) after rotating the rotor at a predetermined angle and then stopping,
A method for diagnosing synchronous machine failures. delete a storage unit for storing a reference impedance; and
Information on AC voltage and AC current applied to the rotor of the synchronous machine is acquired, equivalent impedance is calculated using the AC voltage and AC current, the equivalent impedance is compared with a reference impedance, and the equivalent impedance and the AC current are calculated. A processor for determining whether or not an error has occurred in the synchronizer according to a comparison result between reference impedances;
the processor,
When the equivalent impedance is greater than the reference impedance, it is determined that damage has occurred to the damper bar provided in the rotor,
When the equivalent impedance is smaller than the reference impedance, it is determined that a short circuit has occurred in the field winding provided in the rotor.
Synchronizer failure diagnosis device. delete According to claim 7,
The synchronous machine fault diagnosis device including a synchronous machine of a different excitation type or a self-exciting type synchronous machine. a processor for diagnosing whether the synchronizer is out of order; and
Including; an output unit for outputting a diagnosis result of the processor;
The synchronous machine includes an excitation stator and a rotor, and the rotor includes an excitation rotor, a rectification unit connected to the excitation unit and including at least one diode, and a synchronous rotor connected to the rectification unit,
The processor determines whether distortion occurs in the waveform of the voltage or current applied to the synchronous unit rotor, and if distortion occurs in the waveform of the voltage or current, determines that the at least one diode is open,
the processor,
A voltage or current waveform applied to the synchronous rotor is acquired, and the acquired voltage or current waveform is compared with a reference waveform to determine whether distortion has occurred in the voltage or current waveform, or
Measure the impedance of the field winding of the excitation stator, compare it with the impedance in a settled state, determine whether distortion has occurred in the voltage or current waveform based on the comparison result,
The processor rotates the rotor at a predetermined angle and then stops it, and then determines whether distortion occurs in the voltage or current waveform. If distortion occurs in the voltage or current waveform, the at least one diode Repeatedly performing an operation determined to be open,
Synchronizer failure diagnosis device. delete delete

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