Generator core fault detection method and system

Abstract

The present invention discloses a generator core fault detection method and system for identifying whether a fault exists in a suspected fault location of a generator core. The method includes: installing a local magnetic circuit at the suspected fault location to establish a measurement magnetic circuit; exciting the measurement magnetic circuit to bring the measurement magnetic circuit to a predetermined saturation state and maintaining the state for a predetermined time; collecting thermographic information from the measurement magnetic circuit; and generating a fault determination result based on the thermographic information. Compared with conventional iron loss methods, implementing the present invention significantly reduces the power required for the measurement power supply, making it easy to implement within a nuclear power plant and eliminating the need to transport large and heavy testing equipment. Furthermore, the method is simple and efficient, and can accurately determine whether a fault exists in the core. This effectively reduces the time, effort, and cost of iron loss testing.

Description

[Technical Field]

[0001] The present invention relates to the technical field of electrical maintenance, and in particular to a method and system for detecting faults in a generator core. [Background technology]

[0002] Stator cores are important components of large generators and are typically manufactured by laminating hundreds of thousands of 0.35mm or 0.5mm thick fan-shaped silicon steel plates. If poor insulation occurs between the core laminations, the magnetic field acting during operation will cause large eddy current losses between the laminations, resulting in localized overheating and resulting in damage to the core or stator bars, resulting in significant losses. Therefore, insulation diagnosis of core laminations is an important task in generator inspection and repair.

[0003] Currently, the main diagnostic methods used for inspection and repair are the iron loss method and the ELCID (Electromagnetic Core Imperfection Detector) method.

[0004] The iron loss method intuitively reflects the temperature rise at the fault location, making it possible to assess the severity of the fault. However, iron loss testing of large generators often requires an MVA-class power supply, which is difficult to implement within a power plant. It also requires the transportation of large amounts of test equipment weighing several tons and the connection of dozens of excitation cables, and there is a risk of the fault location overheating and burning, resulting in secondary damage. Furthermore, the excitation cables have a large diameter, requiring personnel to enter the stator hole to measure the temperature. Furthermore, iron loss testing must be performed with the rotor removed, which increases costs and risks.

[0005] In contrast, the ELCID method requires only a few kVA of power, making it easy to obtain within a power plant. Its high sensitivity prevents secondary damage to the fault location. The probe used in the ELCID method is very small and precise, allowing it to be carried by a robot and used to enter the generator without removing the rotor. However, the ELCID method only provides q-axis current, which does not directly reflect temperature rise. While the ELCID method can accurately detect whether a core fault exists, the fault location determined by the ELCID method is often inaccurate. Therefore, when the q-axis current exceeds the standard, a supplementary iron loss test is generally required to determine whether the core fault location can operate safely, before a final determination of the presence or absence of a fault can be made. Furthermore, in practice, the iron loss test may pass even if the q-axis current exceeds the standard, resulting in a significant waste of time, effort, and expense. Summary of the Invention [Problem to be solved by the invention]

[0006] The technical problem that the present invention aims to solve is to provide a method and system for detecting faults in a generator core, which addresses at least one drawback existing in the prior art. [Means for solving the problem]

[0007] The technical means adopted by the present invention to solve the technical problems are as follows:

[0008] A method for detecting a fault in a generator core is provided for determining whether a fault exists in a suspected fault location in the generator core, the method comprising the steps of:

[0009] S1: A local magnetic circuit is installed at the suspected fault location to construct a magnetic circuit for measurement.

[0010] S2: The measuring magnetic circuit is excited to bring the measuring magnetic circuit into a predetermined saturated state, which is maintained for a predetermined time.

[0011] S3: Collect thermographic information of the measurement magnetic circuit, and generate a fault determination result based on the thermographic information.

[0012] Preferably, installing a local magnetic circuit at the suspected fault location of S1 includes connecting gear teeth on both sides adjacent to the suspected fault location with pre-installed magnetic circuit components.

[0013] Preferably, the pre-installed magnetic circuit component includes a magnetic circuit component body and an excitation winding provided on the magnetic circuit component body for applying magnetic field energy to the measurement magnetic circuit, and two contact surfaces of the magnetic circuit component body are in close contact with surfaces of gear teeth on both sides of the suspected fault location, respectively.

[0014] Preferably, the magnetic circuit component body includes a cross beam and first and second side posts extending outward from both ends of the cross beam, and the effective cross-sectional areas of the cross beam, first and second side posts are equal to or greater than the area of ​​the tips of the gear teeth.

[0015] Preferably, step S2 includes collecting the induced voltage at the suspected fault location, adjusting the input voltage of the excitation winding having a predetermined frequency so that the induced voltage at the suspected fault location becomes equal to a predetermined saturation voltage of the measuring magnetic circuit, and maintaining this for a predetermined time.

[0016] Preferably, the pre-installed magnetic circuit components further include a measuring coil for measuring the induced voltage.

[0017] Accordingly, collecting the induced voltage at the suspected fault location in S2 includes collecting the measured voltage of the measuring coil and calculating the induced voltage at the suspected fault location based on the number of turns of the measuring coil and the measured voltage.

[0018] The formula for the induced voltage is Us=Ut / N2.

[0019] In the formula, Us is the induced voltage, Ut is the measurement voltage, and N2 is the number of turns of the measurement coil.

[0020] Preferably, in S2, the formula for the predetermined saturation voltage is Ub=Bb*(4.44*fb*St).

[0021] Ub is a predetermined saturation voltage, Bb is a predetermined saturation magnetic induction strength in the magnetic circuit for measurement, fb is the predetermined frequency, and St is the contact area between the magnetic circuit component body and the gear teeth.

[0022] Preferably, generating a fault determination result based on the thermographic information in S3 includes extracting temperature features from the thermographic information to determine whether or not a region whose temperature is higher than a fault temperature exists in the generator core portion in the measurement magnetic circuit, and if so, determining that a fault exists in the generator core, and if not, determining that no fault exists in the generator core.

[0023] The present invention further provides a generator core fault detection system for identifying whether a fault exists in a suspected fault location of a generator core, the system including: pre-installed magnetic circuit components for constructing a measurement magnetic circuit; an excitation unit for exciting the constructed measurement magnetic circuit to bring the measurement magnetic circuit to a predetermined saturated state and maintaining this state for a predetermined time; a thermography collection unit for collecting thermography information of the measurement magnetic circuit; and a judgment unit for generating a fault judgment result based on the thermography information.

[0024] Preferably, the pre-installed magnetic circuit components include an excitation winding and a measurement coil, and the excitation unit includes a high-frequency power supply for applying an input voltage to the excitation winding, a voltage collector for measuring the measurement voltage of the measurement coil, and an excitation control unit for controlling the output voltage of the high-frequency power supply based on the measurement voltage to bring the measurement magnetic circuit into a predetermined saturated state and maintain this for a predetermined period of time. [Effects of the Invention]

[0025] The present invention has at least the following beneficial effects: A fault detection method for a generator core is provided. This method first installs a local magnetic circuit at a suspected fault location to establish a measurement magnetic circuit, and then excites the measurement magnetic circuit. A low-power power supply can be used for the excitation. Even in this case, the measurement magnetic circuit can be driven to a predetermined saturation state. After a predetermined period of time, thermography information of the measurement magnetic circuit is collected. Finally, a fault determination result is generated based on the thermography information. Compared with the conventional iron loss method, the implementation of this invention significantly reduces the power required for the measurement power supply, making it easy to implement within a nuclear power plant and eliminating the need to transport large and heavy testing equipment. Furthermore, this method is simple and efficient, and can accurately determine whether a fault exists in the core. This effectively reduces the time, workload, and cost of iron loss testing.

[0026] The present invention will be further described below in combination with the drawings and examples. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a flowchart of the generator core fault detection method provided in the present invention. [Figure 2] Figure 2 is a schematic structural diagram of a core in a certain nuclear power plant. [Figure 3] FIG. 3 is a schematic structural diagram of a pre-installed magnetic circuit component in the present invention. [Figure 4] FIG. 4 is a schematic structural diagram of the generator core fault detection system provided in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] In order to make the technical features, objects and effects of the present invention more clearly understood, specific embodiments of the present invention will now be described in detail with reference to the drawings.

[0029] It should be noted that the flowcharts shown in the figures are merely illustrative and do not necessarily include all the contents and operations / steps, nor do they necessarily have to be performed in the order described. For example, some operations / steps may be separated, or some operations / steps may be integrated or partially integrated. Therefore, the order of actual execution may be changed according to actual circumstances.

[0030] The blocks shown in the figures only represent functional entities that do not necessarily correspond to physically separate entities, i.e., they may be implemented in software form, in one or more hardware modules or integrated circuits, or in different networks and / or processor and / or microcontroller devices.

[0031] Referring to Fig. 1, the present invention provides a fault detection method for a generator core for determining whether a fault exists at a suspected fault location of the generator core, the method including steps S1, S2, and S3.

[0032] Step S1 includes installing a local magnetic circuit at a suspected fault location to construct a magnetic circuit for measurement.

[0033] In some embodiments, installing a local magnetic circuit at the suspected fault location in step S1 includes establishing a magnetic circuit for measurement by connecting gear teeth on both sides adjacent to the suspected fault location with pre-installed magnetic circuit components 2. Specifically, as shown in FIG. 2, for example, if the suspected fault location 111 is located on gear tooth 11b or a yoke portion in the radial direction of gear tooth 11b, pre-installed magnetic circuit components 2 may be installed on gear teeth 11a and 11c located on both sides adjacent to gear tooth 11b. Note that gear teeth refer to the respective protruding portions on gears used for meshing.

[0034] 2, in some embodiments, the pre-installed magnetic circuit component 2 includes a magnetic circuit component body 21 and an excitation winding 22 provided in the magnetic circuit component body 21 to impart magnetic field energy to the magnetic circuit for measurement. Two contact surfaces of the magnetic circuit component body 21 are in close contact with the surfaces of the gear teeth on both sides of the suspected fault location, respectively.

[0035] Furthermore, the smaller the effective cross-sectional area of ​​the measurement magnetic circuit, the easier and faster the measurement magnetic circuit will saturate. However, if the measurement magnetic circuit saturates too quickly, the core will heat up too quickly, affecting measurement accuracy. Furthermore, the maximum effective cross-sectional area of ​​the measurement magnetic circuit is limited by the area of ​​the tooth tip plane of the gear teeth. To prevent the measurement magnetic circuit from saturating too quickly during measurement, in some embodiments, the magnetic circuit component body 21 may be a C-shaped column, as shown in FIG. 3 . The C-shaped column includes a cross beam 211 and first and second side columns 212 and 213 extending outward from both ends of the cross beam 211. In addition, the excitation winding 22 can be wound around the first side column 212. The effective cross-sectional areas of the cross beam 211, first side column 212, and second side column 213 are equal to or greater than the tooth tip area of ​​the gear teeth. Preferably, the end faces of the first and second side columns 212 and 213 are aligned with the tooth tip plane of the gear teeth.

[0036] In this embodiment, the role of the pre-installed magnetic circuit component 2 is to reduce the excitation power required for core fault detection by constructing a measurement magnetic circuit with a relatively small effective cross-sectional area and magnetic circuit. The specific principle is as follows.

[0037] Refer to Figure 3. In the present invention, after constructing a magnetic circuit for measurement using pre-installed magnetic circuit components 2, the circuit at the fault location corresponds to a coil with one turn. In addition, the parameters have the following relationship:

[0038]

number

[0039] S1 is the first excitation power, U1 is the first excitation voltage, f1 is the first frequency, wt is the gear tooth width, lt is the gear tooth length, B1 is the first magnetic induction strength, I1 is the first excitation current, lc is the iron core width of the magnetic circuit component body 21, hc is the iron core height of the magnetic circuit component body 21, ht is the gear tooth height, and H1 is the first magnetic field strength.

[0040] Refer to Figure 2. In the related art, when measuring by the iron loss method, the parameters of the circuit at the fault location have the following relationship:

[0041]

number

[0042] S2 is the second excitation power, U2 is the second excitation voltage, f2 is the second frequency, lu is the effective length of the iron core, hy is the height of the yoke part of the core, B2 is the second magnetic induction strength, I2 is the second excitation current, D1 is the outer diameter of the iron core, and H2 is the second magnetic field strength.

[0043] When the frequencies, magnetic induction strengths, and magnetic field strengths of both are the same (i.e., f1=f2, B1=B2, H1=H2), as is clear from equations (1) and (2), the ratio of the power supply power between the method of the present invention and the iron loss method is as follows:

[0044]

number

[0045] In some examples, for a certain model, D1 is 2.99 m, yoke height hy is 0.525 m, lu is 6.4 m, ht is 0.215 m, lc is 0.232 m, hc is 0.1 m, wt is 0.058 m, and lt is 0.1 m. By substituting this into equation (3), it is found that the ratio of power supply power between the method of the present invention and the iron loss method is 0.00032. In this example, compared to the iron loss method, the present invention allows the power supply power for measurement to be reduced to 1 / 3125 of the original power supply power.

[0046] In addition, in this embodiment, the excitation winding 22 and the circuit at the fault location form an electrical structure similar to a transformer, so the input voltage and input current of the excitation winding 22 have the following relationship:

[0047]

number

[0048] U3 is the input voltage of the excitation winding 22, N is the number of turns of the excitation winding 22, and I3 is the input current of the excitation winding 22.

[0049] As is clear from equation (4), when the excitation voltage and excitation current are stable, the input voltage U3 of the excitation winding 22 is directly proportional to the number of turns N, and the input current I3 of the excitation winding 22 is inversely proportional to the number of turns N. Therefore, during measurement, the number of turns can be adjusted based on the output voltage and current of the measurement power supply. For example, the higher the output voltage of the measurement power supply, the greater the number of turns.

[0050] Step S2 involves exciting the magnetic circuit for measurement, bringing it to a predetermined saturated state and maintaining that state for a predetermined time. The role of the excitation process is as follows: the magnetic circuit containing the suspected fault is brought to a predetermined saturated state similar to that observed during iron loss measurement. That is, the magnetic induction strength of the magnetic circuit is set to 1.4 T. Furthermore, the induced voltage generated at the fault location is made to match the induced voltage generated during iron loss measurement. This makes the heat generated at the fault location the same as that generated during iron loss measurement.

[0051] In some embodiments, step S2 includes collecting the induced voltage at the suspected fault location, adjusting the input voltage of the excitation winding 22 to have a predetermined frequency so that the induced voltage at the suspected fault location is equal to a predetermined saturation voltage of the magnetic circuit being measured, and maintaining this for a predetermined time.

[0052] In some embodiments, the pre-installed magnetic circuit component 2 further includes a measuring coil 23 for measuring the induced voltage. The measuring coil 23 can be installed on the second side pole 213. Accordingly, collecting the induced voltage at the suspected fault location in step S2 includes collecting the measured voltage of the measuring coil 23 and calculating the induced voltage at the suspected fault location based on the number of turns of the measuring coil 23 and the measured voltage. In some embodiments, both ends of the measuring coil 23 can be connected to a voltmeter to collect the measured voltage.

[0053] Since the circuit at the fault location corresponds to a coil with one turn and is wound around the same measurement magnetic circuit as the measurement coil, the formula for the induced voltage in step S2 is Us=Ut / N2 (4), where Us is the induced voltage, Ut is the measurement voltage, and N2 is the number of turns of the measurement coil 23.

[0054] Similarly, since the circuit at the fault location corresponds to a coil with one turn, when the magnetic circuit for measurement reaches a predetermined saturated state, the magnetic strength calculation formula B=U / (4.44*f*N*S) gives: The formula for the predetermined saturation voltage can be derived as follows: Ub=Bb*(4.44*fb*St) (5), where Ub is the predetermined saturation voltage, Bb is the predetermined saturation magnetic induction strength in the measuring magnetic circuit (typically 1.4 T), 4.44 is the induced electromotive force coefficient, fb is the predetermined frequency, and St is the contact area between the magnetic circuit component body 21 and the gear teeth.

[0055] As can be seen from the relevant data of the iron loss method, when measured, the fault location circuit at the fault location of the core has the following relationship:

[0056]

number

[0057] Iff is the fault current during the iron loss test, Uff is the induced voltage at the fault location during the iron loss test, R is the resistance of the circuit at the fault location, f3 is the third frequency, B3 is the third magnetic induction strength (generally 1.4T), and Sy is the area of ​​the yoke part of the core (i.e., the effective cross-sectional area of ​​the magnetic circuit).

[0058] From formula (6), we can obtain the formula for the induced voltage at the fault location during iron loss testing: Uff=4.44*fff*B3*Sy (7). To ensure that the induced voltage when the measurement magnetic circuit reaches a predetermined saturation state matches the induced voltage in the iron loss method, i.e., to satisfy Ub=Uff, we can see from formulas (5) and (7) that fb*St must be equal to fff*Sy. Here, since the measurement frequency in the iron loss method is generally set to 50Hz, the desired frequency can be set using the formula fb=50*Sy / St, where Sy is the cross-sectional area of ​​the yoke.

[0059] As is clear from equation (5), when Bb, f, and St are all specific values, a specific theoretical value of Ub can be obtained. As can be seen, the control device can collect the measured voltages and calculate the induced voltage based on the induced voltage equation accordingly. The control device controls the induced voltage Us by adjusting the magnitude of the input voltage to the excitation winding 22. When the induced voltage Us becomes equal to Ub, this means that the measuring magnetic circuit has reached a predetermined saturation state. Therefore, the control device stops adjusting the input voltage to the excitation winding 22 and continues this for a predetermined time before executing step S3.

[0060] Step S3 includes collecting thermographic information of the measurement magnetic circuit and generating a fault determination result based on the thermographic information.

[0061] In some embodiments, generating a fault determination result based on the thermographic information in step S3 includes: extracting temperature features from the thermographic information to determine whether a region in the generator core portion within the measurement magnetic circuit has a temperature higher than the fault temperature; if a region in the generator core portion has a temperature higher than the fault temperature, this indicates that a fault exists in that region, and the internal resistance has increased, resulting in a greater amount of heat generation in that region than in other normal regions. Therefore, it is determined that a fault exists in that region; on the other hand, if no region in the generator core portion has a temperature higher than the fault temperature, this indicates that the amount of heat generation in the generator core portion within the measurement magnetic circuit is uniform, and it is determined that no fault exists in the generator core.

[0062] Referring to Fig. 4, the present invention further provides a generator core fault detection system for determining whether a fault exists at a suspected fault location of a generator core 1. The generator core fault detection system includes a pre-installed magnetic circuit component 2, an excitation unit 3, a thermography collection unit 4, and a judgment unit 5.

[0063] The pre-installed magnetic circuit components 2 are used to construct a magnetic circuit for measurement.

[0064] The excitation unit 3 is used to excite the constructed measurement magnetic circuit, bring the measurement magnetic circuit into a predetermined saturated state, and maintain this state for a predetermined period of time.

[0065] The thermography collection unit 4 is used to collect thermography information of the measuring magnetic circuit.

[0066] The judgment unit 5 is used to generate a fault judgment result based on the thermography information.

[0067] In some embodiments, as shown in FIG. 2 , the pre-installed magnetic circuit component 2 includes a magnetic circuit component body 21, an excitation winding, and a measurement coil. Two contact surfaces of the magnetic circuit component body 21 are used for close contact and connection with the surfaces of the gear teeth on both sides of the suspected fault location. The excitation winding 22 and the measurement coil 23 are each provided on the magnetic circuit component body 21. The excitation winding 22 is for applying magnetic field energy to the measurement magnetic circuit. The measurement coil 23 is used to collect induced voltage at the suspected fault location.

[0068] In some embodiments, the excitation unit 3 includes a high frequency power source, a voltage collector and an excitation control unit.

[0069] The high frequency power supply is a high frequency power supply for applying an input voltage to the excitation winding 22 .

[0070] The voltage collector is a voltage collector for measuring the measurement voltage of the measuring coil 23. Furthermore, the voltage collector may be a voltmeter.

[0071] The excitation control unit is used to control the output voltage of the high frequency power supply based on the measurement voltage, thereby bringing the measurement magnetic circuit into a predetermined saturated state and maintaining this state for a predetermined period of time.

[0072] The present invention has at least the following beneficial effects: A fault detection method for a generator core is provided. This method first installs a local magnetic circuit at a suspected fault location to establish a measurement magnetic circuit, and then excites the measurement magnetic circuit. A low-power power supply can be used for the excitation. Even in this case, the measurement magnetic circuit can be driven to a predetermined saturation state. After a predetermined period of time, thermography information of the measurement magnetic circuit is collected. Finally, a fault determination result is generated based on the thermography information. Compared with the conventional iron loss method, the implementation of this invention significantly reduces the power required for the measurement power supply, making it easy to implement within a nuclear power plant and eliminating the need to transport large and heavy testing equipment. Furthermore, this method is simple and efficient, and can accurately determine whether a fault exists in the core. This effectively reduces the time, workload, and cost of iron loss testing.

[0073] It is understood that the above examples merely illustrate preferred embodiments of the present invention, and although they have been described with relative specificity and detail, they should not be construed as limiting the scope of the present invention. It should also be noted that those skilled in the art may freely combine the above technical features and make slight modifications and improvements without departing from the concept of the present invention, and all of these fall within the scope of protection of the present invention. Therefore, all equivalent conversions and modifications made based on the scope of the claims of the present invention shall also fall within the scope of the claims of the present invention.

Claims

1. A generator core fault detection method for identifying whether or not a fault exists in a suspected fault location of a generator core, comprising: S1: A step of installing a local magnetic circuit at the suspected fault location to construct a measurement magnetic circuit; S2: A step of exciting the measuring magnetic circuit to bring the measuring magnetic circuit into a predetermined saturated state and maintaining this for a predetermined time; S3: collecting thermography information of the measurement magnetic circuit and generating a fault determination result based on the thermography information.

2. 2. The generator core fault detection method according to claim 1, wherein in step S1, installing a local magnetic circuit at the suspected fault location includes connecting gear teeth on both sides adjacent to the suspected fault location with pre-installed magnetic circuit components.

3. 3. The generator core fault detection method according to claim 2, wherein the pre-installed magnetic circuit component includes a magnetic circuit component body and an excitation winding provided on the magnetic circuit component body to impart magnetic field energy to the measurement magnetic circuit, and two contact surfaces of the magnetic circuit component body are in close contact with surfaces of gear teeth on both sides of the suspected fault location, respectively.

4. 4. The generator core fault detection method according to claim 3, wherein the magnetic circuit component body includes a cross beam and first and second side columns extending outward from both ends of the cross beam, and the effective cross-sectional areas of the cross beam, the first and second side columns are equal to or greater than the tip areas of the gear teeth.

5. 4. The generator core fault detection method according to claim 3, wherein step S2 includes collecting induced voltages at the suspected fault location, adjusting an input voltage of an excitation winding having a predetermined frequency so that the induced voltage at the suspected fault location becomes equal to a predetermined saturation voltage of the measuring magnetic circuit, and maintaining this for a predetermined time.

6. the pre-installed magnetic circuit component further includes a measuring coil for measuring the induced voltage; collecting the induced voltage at the suspected fault location in step S2 includes collecting a measured voltage of the measurement coil, and calculating the induced voltage at the suspected fault location based on the number of turns of the measurement coil and the measured voltage; The formula for the induced voltage is Us = Ut / N2, 6. The generator core fault detection method according to claim 5, wherein Us is the induced voltage, Ut is the measured voltage, and N2 is the number of turns of the measuring coil.

7. In step S2, the formula for the predetermined saturation voltage is Ub=Bb*(4.44*fb*St), 7. The generator core fault detection method according to claim 6, wherein Ub is a predetermined saturation voltage, Bb is a predetermined saturation magnetic induction strength in the measurement magnetic circuit, fb is the predetermined frequency, and St is a contact area between the magnetic circuit component body and the gear teeth.

8. The generator core fault detection method according to any one of claims 1 to 7, characterized in that generating a fault determination result based on the thermography information in step S3 includes extracting temperature features from the thermography information and determining whether or not an area whose temperature is higher than a fault temperature exists in the generator core portion in the measurement magnetic circuit, and if so, determining that a fault exists in the generator core, and if not, determining that no fault exists in the generator core.

9. A generator core fault detection system for identifying whether or not a fault exists in a suspected fault location of a generator core, comprising: Pre-installed magnetic circuit components for constructing a measurement magnetic circuit; an excitation unit for exciting the constructed measurement magnetic circuit to bring the measurement magnetic circuit into a predetermined saturated state and maintain the state for a predetermined time; a thermography collection unit for collecting thermography information of the measuring magnetic circuit; a judgment unit for generating a fault judgment result based on the thermography information.

10. the pre-installed magnetic circuit components include an excitation winding and a measuring coil; The excitation unit includes: a high frequency power source for applying an input voltage to the excitation winding; a voltage collector for measuring a measured voltage of the measuring coil; 10. The generator core fault detection system according to claim 9, further comprising: an excitation control unit for controlling the output voltage of the high-frequency power supply based on the measured voltage, thereby bringing the measurement magnetic circuit into a predetermined saturated state and maintaining that state for a predetermined time.

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