Method, device and storage medium for simplifying stator turn-to-turn short-circuit model of synchronous condenser

Abstract

The present invention discloses a method, device and storage medium for simplifying a stator turn-to-turn short-circuit model of a synchronous condenser, and relates to the technical field of motor fault diagnosis. First, the existing resistance, inductance and other parameters in a dual-branch synchronous condenser are used to simplify multiple branch equations of each phase into a single-branch equation, and then the motor parameters and characteristics after the fault are used to simplify multiple fault branches of the dual-branch turn-to-turn short-circuit fault into a single-branch fault loop; through the dual-branch turn-to-turn short-circuit model simplification method proposed by the present invention, the stator and rotor voltage and current of the synchronous condenser remain unchanged before and after the simplification, so the stator turn-to-turn short-circuit fault characteristics shown in the voltage and current parts will not be affected, and the calculation process for diagnosing the dual-branch stator turn-to-turn short-circuit fault of the synchronous condenser can be simplified under the premise of ensuring that the voltage and current remain unchanged, which is convenient for analyzing the fault characteristics and reducing the complexity and calculation amount of subsequent diagnosis.

Description

Technical Field

[0001] The present invention relates to a field, and in particular to a method, a device and a storage medium for simplifying a stator turn-to-turn short-circuit model of a synchronous phase regulator. Background Art

[0002] In order to solve the serious imbalance of energy and load distribution and the demand for ultra-high voltage direct current transmission system (UHVDC), ultra-high voltage direct current transmission technology has been widely used. However, its dynamic reactive power support is insufficient, and the problems of converter commutation failure and voltage drop are more prominent. As a reactive power compensation device, the synchronous condenser can be regarded as a synchronous motor without mechanical load. It can not only provide short-circuit capacity for the power system, but also has strong reactive power output characteristics. In ultra-high voltage direct current projects, large-capacity grid-connected synchronous condensers can suppress commutation faults at the DC receiving end and reduce transient overvoltages at the DC sending end. Therefore, installing a synchronous condenser at the converter station at the sending and receiving ends of a multi-circuit ultra-high voltage direct current project can improve the stability of the system.

[0003] The stator side of the synchronous condenser will be subjected to greater stress, which can easily lead to weakening of the insulation of the winding. Long-term development will lead to insulation breakdown of the system and turn-to-turn short circuit. Further deterioration of the fault will produce phase-to-phase short circuit or ground short circuit, causing serious power accidents. Therefore, diagnosing the fault during the stator turn-to-turn short circuit fault is of great significance to the stability of the system. The synchronous condensers currently put into operation usually have a double branch on the stator side. However, it is relatively complicated to directly analyze and diagnose the fault of the double-branch synchronous condenser, especially when combined with the diagnosis method based on the motor model, which will generate a relatively large computational burden. For this reason, a simplified method, device and storage medium for the stator turn-to-turn short circuit model of the synchronous condenser are proposed. The double-branch fault model can be simplified, which can greatly reduce the complexity of fault diagnosis research, reduce the computational amount of the fault diagnosis algorithm based on the motor model, and improve the applicability of the algorithm. Summary of the invention

[0004] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide a simplified method, device and storage medium for the stator inter-turn short-circuit model of a synchronous phase regulator, which solves the technical problem that the process of diagnosing the fault of a dual-branch synchronous phase regulator in the prior art is relatively complicated, thereby generating a large computational burden.

[0005] The object of the present invention can be achieved by the following technical solution: a method for simplifying the stator turn-to-turn short-circuit model of a synchronous condenser, the method comprising the following steps:

[0006] By using the existing resistance and inductance parameters in the dual-branch synchronous phase regulator, the multiple branch equations of each phase are simplified into a single branch equation. Then, by using the parameters and characteristics of the dual-branch synchronous phase regulator after the fault, the multiple fault branches of the dual-branch turn-to-turn short-circuit fault are simplified into a single branch fault loop.

[0007] Furthermore, the simplified model resistance and inductance are calculated using the resistance and inductance of the synchronous phase-converting dual-branch motor:

[0008]

[0009] Among them, R s_I is the simplified phase resistance; L AA_I , L BB_I and L CC_I is the simplified ABC phase self-inductance; M Af_I , M Bf_I and M Cf_I is the simplified mutual inductance of phases ABC and the field winding; M BA_I is the simplified mutual inductance of phase A; and M AB_I is the simplified mutual inductance of phase B; M CA_I is the simplified mutual inductance of phase A, and M AC_I is the simplified mutual inductance of phase C; M CB_I is the simplified mutual inductance of phase B, M BC_I is the simplified mutual inductance of phase C; M AB_I is the simplified mutual inductance between phase A and phase B; M AB_I is the simplified mutual inductance between phases A and B;

[0010] R s_II is the actual resistance of each branch; L A1A1 , L B1B1 and L C1C1 is the actual self-inductance of branch A1, branch B1, and branch C1; M A1f , M A2f , M B1f , M B1f , M C1f and M C2f is the mutual inductance of the actual A1 branch, A2 branch, B1 branch, B2 branch, C1 branch, C2 branch and the excitation winding; M A2A1 is the mutual inductance between branch A1 and branch A2; M B2B1 is the mutual inductance between branch B1 and branch B2; M C2C1 is the mutual inductance between branches C1 and C2; M A2B1 is the mutual inductance between branch B1 and branch A2; M B2C1 is the mutual inductance between branch C1 and branch B2; M C2A1 It is the mutual inductance between branch A1 and branch C2.

[0011] Furthermore, the simplified short-circuit resistance and the simplified short-circuit ratio are calculated by using the fault resistance and the short-circuit ratio after the fault:

[0012] μ=α-β

[0013] R k_I =R k_II +[α+3β-(α+β) 2 ]R s_II / 2

[0014] Among them, μ is the simplified short-circuit ratio; α and β are the short-circuit ratios of the two branches in the same phase; R k_I is the simplified short-circuit resistance; R k_II is the actual short-circuit resistance.

[0015] Furthermore, the simplified short-circuit resistance, simplified inductance and simplified short-circuit ratio are substituted into the traditional single-branch fault voltage equation.

[0016]

[0017] in

[0018] u I =[u A_I u B_I u C_I u k_I u f_I ] T

[0019] i I =[i A_I i B_I i C_I i k_I i f_I ] T

[0020]

[0021]

[0022] Among them, u A_I ,u B_I and u C_I is the three-phase voltage; u k_I is the short-circuit winding voltage; u f_I is the excitation voltage; i A_I ,i B_I and i C_I is the three-phase current; i k_I is the short-circuit winding current; i f_I is the excitation current; R k_I is the short-circuit winding resistance; Rf_I is the excitation resistance, L ff is the self-inductance of the excitation winding; thereby simplifying the stator double-branch turn-to-turn short-circuit model of the synchronous phase regulator.

[0023] A device comprising:

[0024] one or more processors;

[0025] A memory for storing one or more programs;

[0026] When the one or more programs are executed by the one or more processors, the one or more processors implement the method for simplifying the stator turn-to-turn short-circuit model of the synchronous phase condenser as described above.

[0027] A storage medium containing computer executable instructions, wherein the computer executable instructions are used to perform the above-mentioned method for simplifying the stator turn-to-turn short-circuit model of a synchronous condenser when executed by a computer processor.

[0028] Beneficial effects of the present invention:

[0029] During use of the present invention, the existing resistance, inductance and other parameters in the dual-branch synchronous phase regulator are first used to simplify the multiple branch equations of each phase into a single branch equation, and then the motor parameters and characteristics after the fault are used to simplify the multiple fault branches of the dual-branch inter-turn short-circuit fault into a single branch fault loop; through the dual-branch inter-turn short-circuit model simplification method proposed by the present invention, the stator and rotor voltages and currents of the synchronous phase regulator remain unchanged before and after the simplification, so the stator inter-turn short-circuit fault characteristics shown in the voltage and current parts will not be affected, and the calculation process of the dual-branch stator inter-turn short-circuit fault diagnosis of the synchronous phase regulator can be simplified under the premise of ensuring that the voltage and current remain unchanged, which is convenient for the analysis of the fault characteristics and reduces the complexity and calculation amount of subsequent diagnosis, and simplifies the dual-branch stator inter-turn short-circuit fault of the synchronous phase regulator into a traditional single-branch model, simplifies the analysis process of the dual-branch fault, and reduces the calculation burden of the model-based fault diagnosis strategy; the applicability of the existing fault diagnosis strategy can be improved, and the existing single-branch diagnosis strategy can be applied to the dual-branch fault diagnosis process in combination with the simplification method. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 It is a circuit topology schematic diagram of a double-branch phase regulator and a single-branch phase regulator of the present invention;

[0032] Figure 2 It is a schematic diagram of the change of three-phase current before and after a fault in the dual-branch model of the present invention;

[0033] Figure 3 It is a schematic diagram of the change of three-phase current before and after the fault of the simplified model of the present invention;

[0034] Figure 4 It is a schematic diagram of the change of short-circuit current before and after a fault in the dual-branch model of the present invention;

[0035] Figure 5 It is a schematic diagram of the change of short-circuit current before and after the fault of the simplified model of the present invention. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] like Figure 1 As shown, a simplified method for the stator turn-to-turn short-circuit model of a synchronous condenser is provided, and the method includes the following steps:

[0038] By using the existing resistance and inductance parameters in the dual-branch synchronous phase regulator, the multiple branch equations of each phase are simplified into a single branch equation. Then, by using the parameters and characteristics of the dual-branch synchronous phase regulator after the fault, the multiple fault branches of the dual-branch turn-to-turn short-circuit fault are simplified into a single branch fault loop.

[0039] It should be further explained that, in the specific implementation process, the simplified model resistance and inductance are calculated using the resistance and inductance of the dual-branch motor of the synchronous phase condenser:

[0040]

[0041] Among them, R s_I is the simplified phase resistance; L AA_I , L BB_I and L CC_I is the simplified ABC phase self-inductance; M Af_I , M Bf_I and M Cf_I is the simplified mutual inductance of phases ABC and the field winding; M BA_I is the simplified mutual inductance of phase A; and M AB_I is the simplified mutual inductance of phase B; M CA_I is the simplified mutual inductance of phase A, and M AC_Iis the simplified mutual inductance of phase C; M CB_I is the simplified mutual inductance of phase B, M BC_I is the simplified mutual inductance of phase C; M AB_I is the simplified mutual inductance between phase A and phase B; M AB_I is the simplified mutual inductance between phases A and B;

[0042] R s_II is the actual resistance of each branch; L A1A1 , L B1B1 and L C1C1 is the actual self-inductance of branch A1, branch B1, and branch C1; M A1f , M A2f , M B1f , M B1f , M C1f and M C2f is the mutual inductance of the actual A1 branch, A2 branch, B1 branch, B2 branch, C1 branch, C2 branch and the excitation winding; M A2A1 is the mutual inductance between branch A1 and branch A2; M B2B1 is the mutual inductance between branch B1 and branch B2; M C2C1 is the mutual inductance between branches C1 and C2; M A2B1 is the mutual inductance between branch B1 and branch A2; M B2C1 is the mutual inductance between branch C1 and branch B2; M C2A1 It is the mutual inductance between branch A1 and branch C2.

[0043] It should be further explained that, in the specific implementation process, the simplified short-circuit resistance and the simplified short-circuit ratio are calculated by using the fault resistance and the short-circuit ratio after the fault:

[0044] μ=α-β

[0045] R k_I =R k_II +[α+3β-(α+β) 2 ]R s_II / 2

[0046] Among them, μ is the simplified short-circuit ratio; α and β are the short-circuit ratios of the two branches in the same phase; R k_I is the simplified short-circuit resistance; R k_II is the actual short-circuit resistance.

[0047] It should be further explained that, in the specific implementation process, the simplified short-circuit resistance, simplified inductance and simplified short-circuit ratio are introduced into the voltage equation of the traditional single-branch fault.

[0048]

[0049] in

[0050] u I =[u A_I u B_I u C_I u k_I u f_I ] T

[0051] i I =[i A_I i B_I i C_I i k_I i f_I ] T

[0052]

[0053]

[0054] Among them, u A_I ,u B_I and u C_I is the three-phase voltage; u k_I is the short-circuit winding voltage; u f_I is the excitation voltage; i A_I ,i B_I and i C_I is the three-phase current; i k_I is the short-circuit winding current; i f_I is the excitation current; R k_I is the short-circuit winding resistance; R f_I is the excitation resistance, L ff is the self-inductance of the excitation winding; thereby achieving the simplification of the stator double-branch turn-to-turn short-circuit model of the synchronous phase condenser, thereby achieving the simplification of the stator double-branch turn-to-turn short-circuit model of the synchronous phase condenser.

[0055] It should be further explained that, in a specific implementation process, a device includes:

[0056] one or more processors;

[0057] A memory for storing one or more programs;

[0058] When the one or more programs are executed by the one or more processors, the one or more processors implement the method for simplifying the stator turn-to-turn short-circuit model of the synchronous phase condenser as described above.

[0059] It should be further explained that, in a specific implementation process, a storage medium containing computer executable instructions, when the computer executable instructions are executed by a computer processor, is used to execute the method for simplifying the stator turn-to-turn short-circuit model of a synchronous phase regulator as described above.

[0060] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A simplified method for the stator turn-to-turn short-circuit model of a synchronous condenser, characterized in that: Methods include the following: By using the existing resistance and inductance parameters in the dual-branch synchronous phase condenser, the multiple branch equations of each phase are simplified into a single branch equation. Then, by using the parameters and characteristics of the dual-branch synchronous phase condenser after the fault, the multiple fault branches of the dual-branch turn-to-turn short-circuit fault are simplified into a single branch fault loop. The simplified model resistance and inductance are calculated using the resistance and inductance of the synchronous phase-converting dual-branch motor: Among them, R s_I is the simplified phase resistance; L AA_I , L BB_I and L CC_I is the simplified ABC phase self-inductance; M Af_I , M Bf_I and M Cf_I is the simplified mutual inductance of phases ABC and the field winding; M BA_I is the simplified mutual inductance of phase A; and M AB_I is the simplified mutual inductance of phase B; M CA_I is the simplified mutual inductance of phase A, and M AC_I is the simplified mutual inductance of phase C; M CB_I is the simplified mutual inductance of phase B, M BC_I is the simplified mutual inductance of phase C; M AB_I is the simplified mutual inductance between phase A and phase B; M AB_I is the simplified mutual inductance between phases A and B; R s_II is the actual resistance of each branch; L A1A1 , L B1B1 and L C1C1 is the actual self-inductance of branch A1, branch B1, and branch C1; M A1f , M A2f , M B1f , M B1f , M C1f and M C2f is the mutual inductance of the actual A1 branch, A2 branch, B1 branch, B2 branch, C1 branch, C2 branch and the excitation winding; M A2A1 is the mutual inductance between branch A1 and branch A2; M B2B1 is the mutual inductance between branch B1 and branch B2; M C2C1 is the mutual inductance between branches C1 and C2; M A2B1 is the mutual inductance between branch B1 and branch A2; M B2C1 is the mutual inductance between branch C1 and branch B2; M C2A1 is the mutual inductance between branch A1 and branch C2; Using the fault resistance after the fault and the short-circuit ratio after the fault, calculate the simplified short-circuit resistance and the simplified short-circuit ratio: Among them, μ is the simplified short-circuit ratio; α and β are the short-circuit ratios of the two branches in the same phase; R k_I is the simplified short-circuit resistance; R k_II is the actual short-circuit resistance; Substitute the simplified short-circuit resistance, simplified inductance and simplified short-circuit ratio into the traditional single-branch fault voltage equation: in in, u A_I , u B_I and u C_I is the three-phase voltage; u k_I is the short-circuit winding voltage; u f_I is the excitation voltage; i A_I , i B_I and i C_I is the three-phase current; i k_I is the short-circuit winding current; i f_I is the excitation current; R k_I is the short-circuit winding resistance; R f_I is the excitation resistance, L ff The self-inductance of the excitation winding is used to simplify the stator double-branch turn-to-turn short-circuit model of the synchronous phase regulator.

2. A device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method for simplifying the stator turn-to-turn short-circuit model of a synchronous condenser as claimed in claim 1.

3. A storage medium containing computer executable instructions, characterized in that: When the computer executable instructions are executed by a computer processor, they are used to perform the method for simplifying the stator turn-to-turn short-circuit model of a synchronous condenser as claimed in claim 1 .

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