A diesel generator harmonic excitation system design method and device

Abstract

The present invention relates to the field of diesel generators, and specifically discloses a diesel generator harmonic excitation system design method and device. In terms of the number of winding turns, parameters are preset, the parameters are extracted to calculate the excitation current, the harmonic excitation power and the magnetic circuit saturation are calculated based on the excitation current, and the number of winding turns is selected based on the harmonic excitation power and the magnetic circuit saturation. In terms of stator slot parameters, the stator slot width and slot depth are determined according to the number of winding turns, the number of winding coils and the winding wire gauge size, and the weight and loss of the stator yoke core are determined according to the stator slot width and slot depth. In terms of rotor parameters, the excitation loss is calculated based on the magnetic cross-section, and the rotor parameters are determined based on the excitation loss. The present invention reasonably determines the number of harmonic winding turns, the stator slot depth and the magnetic cross-section of the rotor teeth, reduces the increase in the weight and loss of the stator yoke core caused by the harmonic excitation method, reduces the excitation loss while ensuring sufficient harmonic power, is simple to operate, and has high work efficiency.

Description

Technical Field

[0001] The invention relates to the field of diesel generators, and in particular to a diesel generator harmonic excitation system design method and device. Background Art

[0002] Harmonic excitation is a new technology developed in the 1960s. It installs a harmonic winding on the generator stator to draw out the third harmonic power stored in the air gap magnetic field of the generator, and after rectification by the thyristor rectifier, it is used for excitation of the rotor body. The structural feature of the harmonic winding is that each coil of the harmonic winding is composed of three conductors in series, and the pitch of the third harmonic coil = 1 / 3 pole pitch. It is easy to know from the phasor analysis that the harmonic coil only induces the third harmonic potential and the harmonic potential of odd multiples of three, and the potential of the entire coil is 3 times the potential of a conductor, and no other harmonic potential is induced. In other words, the harmonic winding is specially used to obtain the third harmonic power. It is an independent power supply without interconnection with the main winding. (The fundamental wave and harmonics do not affect each other) The third harmonic current increases with the increase of the main current. The increase of the main current has a demagnetizing effect, which reduces the voltage. In order to stabilize the voltage, the excitation current must be increased; the third harmonic current automatically increases synchronously, which increases the excitation current and increases the voltage, thereby playing a role in stabilizing the voltage.

[0003] However, in practical applications, it is found that there are also some problems in the design and manufacture of diesel generator harmonic excitation systems:

[0004] 1. When harmonic excitation is used, the design of the host will be affected

[0005] (1) To obtain a larger harmonic power, a larger pole arc coefficient value must be selected, which will relatively reduce the magnetic cross-section of the rotor teeth, increase the excitation current, and thus increase its saturation degree. At the same time, it also reduces the winding coefficient of the excitation winding. However, if the excitation current is too large, the excitation loss will increase, which in turn increases the rotor temperature rise.

[0006] (2) To place the harmonic winding, the stator slots generally need to be deepened, which will inevitably increase the weight and loss of the stator yoke core.

[0007] (3) To obtain a symmetrical and balanced harmonic winding, the number of stator slots must be selected to a certain value, which often makes the design of the main engine not the best solution.

[0008] 2. Improper design of harmonic windings may sometimes result in insufficient harmonic power.

[0009] 3. The number of turns of the harmonic winding is not designed properly. Summary of the invention

[0010] In order to solve the above problems, the present invention provides a method and device for designing a harmonic excitation system of a diesel generator.

[0011] In a first aspect, the technical solution of the present invention provides a method for designing a harmonic excitation system of a diesel generator, comprising the following steps:

[0012] Extract the data from the electromagnetic calculation sheet of the diesel generator and calculate the required harmonic excitation rated power;

[0013] Preset harmonic winding parameters and set the value range of harmonic winding parameters; the harmonic winding parameters include winding current, winding turns and corresponding winding area;

[0014] Within the range of harmonic winding parameter values, extract the harmonic winding parameters multiple times according to a preset step size to calculate the excitation current;

[0015] Calculate harmonic excitation power and magnetic circuit saturation based on excitation current;

[0016] Determine whether the calculated harmonic excitation power meets the harmonic excitation rated power, and if so, save the corresponding magnetic circuit saturation and harmonic winding parameters;

[0017] Among all the saved magnetic circuit saturations and harmonic winding parameters, the harmonic winding parameter corresponding to the maximum magnetic circuit saturation is selected, and the number of winding turns of the harmonic winding parameter is the number of winding turns of the harmonic excitation system finally determined.

[0018] Furthermore, the winding current has a value range of 2 to 4A.

[0019] Furthermore, the method further comprises the following steps:

[0020] Determine the number of winding coils according to the number of winding turns;

[0021] Select winding wire gauge size;

[0022] Determine the stator slot width and slot depth according to the number of winding turns, the number of winding coils and the winding wire gauge size;

[0023] The weight and loss of the stator yoke core are determined according to the stator slot width and slot depth.

[0024] Furthermore, the method further comprises the following steps:

[0025] Select the rotor diameter and number of slots according to the slot fit, and obtain the magnetic cross section of the rotor teeth;

[0026] Under the obtained magnetic cross-section conditions, calculate the excitation loss;

[0027] Determine whether the harmonic excitation power meets the standard under the calculated excitation loss;

[0028] If the conditions are met, the corresponding magnetic cross section, rotor diameter and number of slots are saved;

[0029] Among all the saved magnetic conductive cross-sections, rotor diameters and slot numbers, the magnetic conductive cross-section, rotor diameter and slot number with the smallest excitation loss are selected as the final system parameters.

[0030] In a second aspect, the technical solution of the present invention provides a diesel generator harmonic excitation system design device, comprising:

[0031] Harmonic excitation rated power calculation module: extract the data in the electromagnetic calculation sheet of the diesel generator and calculate the required harmonic excitation rated power;

[0032] Harmonic winding parameter preset module: preset harmonic winding parameters and set the value range of harmonic winding parameters; the harmonic winding parameters include winding current, winding turns and corresponding winding area;

[0033] Excitation current calculation module: within the range of harmonic winding parameter values, the harmonic winding parameters are extracted multiple times according to the preset step length to calculate the excitation current;

[0034] Power / saturation calculation module: calculates harmonic excitation power and magnetic circuit saturation based on excitation current;

[0035] The first power judgment module is used to judge whether the calculated harmonic excitation power meets the harmonic excitation rated power. If so, the corresponding magnetic circuit saturation and harmonic winding parameters are saved.

[0036] Parameter determination module: among all the saved magnetic circuit saturations and harmonic winding parameters, the harmonic winding parameter corresponding to the maximum magnetic circuit saturation is selected, and the number of winding turns of the harmonic winding parameter is the number of winding turns of the harmonic excitation system finally determined.

[0037] Furthermore, the value range of the winding current preset by the harmonic winding parameter preset module is 2 to 4A.

[0038] Furthermore, the device also includes:

[0039] Winding coil number determination module: determines the number of winding coils according to the number of winding turns;

[0040] Winding wire gauge size selection module: select winding wire gauge size;

[0041] Stator slot parameter determination module: determines the stator slot width and slot depth according to the number of winding turns, the number of winding coils and the winding wire gauge size;

[0042] Stator yoke core determination module: determines the weight and loss of the stator yoke core according to the stator slot width and slot depth.

[0043] Furthermore, the device also includes:

[0044] Rotor parameter selection module: selects the rotor diameter and number of slots according to the slot matching, and obtains the magnetic cross-section of the rotor teeth;

[0045] Excitation loss calculation module: calculate the excitation loss under the obtained magnetic cross-section conditions;

[0046] The second power judgment module is used to judge whether the harmonic excitation power meets the standard under the calculated excitation loss;

[0047] Rotor parameter saving module: if the conditions are met, the corresponding magnetic cross section, rotor diameter and number of slots are saved;

[0048] Rotor parameter determination module: Among all the saved magnetic conductive sections, rotor diameters and slot numbers, the magnetic conductive section, rotor diameter and slot number with the smallest excitation loss are selected as the final system parameters.

[0049] The present invention provides a diesel generator harmonic excitation system design method and device, which has the following beneficial effects: preset parameters, according to the electromagnetic calculation of the generator, reasonably determine the number of harmonic winding turns, determine the stator slot depth, reduce the weight and loss of the stator yoke core caused by the harmonic excitation method, and design the magnetic conductive section of the rotor teeth to reduce the excitation loss while ensuring sufficient harmonic power. The present invention is simple to operate, has high working efficiency, and can reasonably design the diesel generator harmonic excitation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present application or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0051] Figure 1 It is a flow chart of a method for designing the number of winding turns in a method for designing a harmonic excitation system of a diesel generator provided in Embodiment 1 of the present invention.

[0052] Figure 2 It is a flow chart of a stator slot parameter design method in a diesel generator harmonic excitation system design method provided in Embodiment 1 of the present invention.

[0053] Figure 3 It is a flow chart of a rotor parameter design method in a diesel generator harmonic excitation system design method provided in Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0054] The present invention will be described in detail below with reference to the accompanying drawings and through specific embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following implementation modes.

[0055] Embodiment 1

[0056] The first embodiment provides a diesel generator harmonic excitation system design method, including the design of winding turns, stator slot parameters and rotor parameters.

[0057] like Figure 1 As shown, the design of the number of winding turns in this design method includes the following steps.

[0058] S101, extracting data from the electromagnetic calculation sheet of the diesel generator and calculating the required harmonic excitation rated power.

[0059] A preliminary calculation yields the required harmonic excitation rated power, calculated according to the following formula:

[0060] P=1.732*COSφ*U*I*η

[0061] Among them, P is power, U is voltage, I is current, η is efficiency, and COSφ is power factor.

[0062] S102, presetting harmonic winding parameters and setting a value range of the harmonic winding parameters; wherein the harmonic winding parameters include winding current, winding turns and corresponding winding area.

[0063] According to the design requirements, the harmonic winding parameters and the value range of the parameters are preset. For example, in a specific implementation, the value range of the winding current is 2 to 4A.

[0064] S103, within the harmonic winding parameter value range, extract the harmonic winding parameters multiple times according to a preset step size to calculate the excitation current.

[0065] Calculated according to the excitation current formula:

[0066] J=N*I / S

[0067] J is the excitation current, N is the number of turns, I is the winding current, and S is the winding area.

[0068] Extract data from the saved harmonic winding parameters and calculate the excitation current using the above formula. In specific implementation, after the initial extraction of parameters, the second calculation is performed based on the first extracted parameters according to the preset step size. For example, if the initial extracted winding current is 2A and the step size is 0.2A, the winding current is 2.2A in the second calculation.

[0069] The preset step size can be adjusted according to the magnetic circuit saturation. When the magnetic circuit saturation is small, a large step size is taken, and when the magnetic circuit saturation is large, a small step size is taken.

[0070] S104, calculating the harmonic excitation power and the magnetic circuit saturation based on the excitation current.

[0071] S105, determining whether the calculated harmonic excitation power meets the harmonic excitation rated power, and if so, saving the corresponding magnetic circuit saturation and harmonic winding parameters.

[0072] S106, selecting the harmonic winding parameter corresponding to the maximum magnetic circuit saturation from among all the stored magnetic circuit saturations and harmonic winding parameters, the number of winding turns of the harmonic winding parameter being the number of winding turns of the harmonic excitation system finally determined.

[0073] In this embodiment, the number of winding turns is selected based on the harmonic excitation power and the magnetic circuit saturation. Among all harmonic winding parameters whose harmonic excitation power satisfies the harmonic excitation rated power, the harmonic winding parameter corresponding to the maximum magnetic circuit saturation is selected. The number of winding turns of the harmonic winding parameter is the number of winding turns of the harmonic excitation system finally determined.

[0074] Through the above steps, the number of turns of the harmonic winding can be reasonably designed.

[0075] like Figure 2 As shown, the stator slot parameter design in this design method includes the following steps.

[0076] S201, determining the number of winding coils according to the number of winding turns.

[0077] In the above steps, the number of winding turns has been determined, and the number of roots to be removed first is determined based on the determined number of winding turns.

[0078] S202, select the winding wire gauge size.

[0079] Select winding wire gauge size based on national standards.

[0080] S203, determining the stator slot width and slot depth according to the number of winding turns, the number of winding coils and the winding wire gauge.

[0081] S204, determining the weight and loss of the stator yoke core according to the stator slot width and slot depth.

[0082] According to the above steps, the stator slot depth is reasonably designed to reduce the increase in stator yoke core weight and loss caused by the harmonic excitation method.

[0083] like Figure 3 As shown, the rotor parameter design in this design method includes the following steps.

[0084] S301, selecting a rotor diameter and a number of slots according to slot matching, and obtaining a magnetic conductive cross section of a rotor tooth.

[0085] It should be noted that the slot matching is adjusted in advance to ensure the symmetry and balance of the harmonic winding.

[0086] S302, calculating the excitation loss under the obtained magnetic conductive cross-section condition.

[0087] S303, judging whether the harmonic excitation power meets the standard under the calculated excitation loss.

[0088] S304: If the conditions are met, the corresponding magnetic cross-section, rotor diameter and number of slots are saved.

[0089] S305 , among all the saved magnetic conductive cross-sections, rotor diameters and slot numbers, select the magnetic conductive cross-section, rotor diameter and slot number with the minimum excitation loss as the final system parameters.

[0090] This embodiment minimizes excitation loss while ensuring sufficient harmonic power. By implementing the above steps, the magnetic conductive cross-section of the rotor teeth can be reasonably set to reduce excitation loss while ensuring sufficient harmonic power.

[0091] The diesel generator is manufactured according to the above-mentioned design parameters, the harmonic winding has a reasonable number of turns, the weight and loss of the stator yoke core are low, it has sufficient harmonic power, and the excitation loss is small.

[0092] Embodiment 2

[0093] Based on the first embodiment, the second embodiment provides a diesel generator harmonic excitation system design device, which is used to implement the diesel generator harmonic excitation system design method of the first embodiment.

[0094] The device of the second embodiment realizes the design of the number of winding turns, stator slot parameters and rotor parameters.

[0095] Specifically, the winding turns design includes the following functional modules.

[0096] Harmonic excitation rated power calculation module: extract the data in the electromagnetic calculation sheet of the diesel generator and calculate the required harmonic excitation rated power.

[0097] Harmonic winding parameter preset module: preset harmonic winding parameters and set the value range of harmonic winding parameters; harmonic winding parameters include winding current, winding turns and corresponding winding area. The value range of the winding current preset by this module is 2~4A.

[0098] Excitation current calculation module: within the range of harmonic winding parameter values, the harmonic winding parameters are extracted multiple times according to the preset step size to calculate the excitation current.

[0099] Power / saturation calculation module: Calculates harmonic excitation power and magnetic circuit saturation based on excitation current.

[0100] The first power judgment module is used to judge whether the calculated harmonic excitation power meets the harmonic excitation rated power. If so, the corresponding magnetic circuit saturation and harmonic winding parameters are saved.

[0101] Parameter determination module: among all the saved magnetic circuit saturations and harmonic winding parameters, the harmonic winding parameter corresponding to the maximum magnetic circuit saturation is selected, and the number of winding turns of the harmonic winding parameter is the number of winding turns of the harmonic excitation system finally determined.

[0102] Specifically, the stator slot parameter design includes the following functional modules.

[0103] Winding coil number determination module: determines the number of winding coils according to the number of winding turns.

[0104] Winding wire gauge size selection module: select the winding wire gauge size.

[0105] Stator slot parameter determination module: determines the stator slot width and slot depth according to the number of winding turns, the number of winding coils and the winding wire gauge size.

[0106] Stator yoke core determination module: determines the weight and loss of the stator yoke core according to the stator slot width and slot depth.

[0107] Specifically, the rotor parameters include the following functional modules.

[0108] Rotor parameter selection module: select the rotor diameter and number of slots according to the slot fit, and obtain the magnetic cross-section of the rotor teeth.

[0109] Excitation loss calculation module: calculate the excitation loss under the obtained magnetic cross-section conditions.

[0110] The second power judgment module is used to judge whether the harmonic excitation power meets the standard under the calculated excitation loss.

[0111] Rotor parameter saving module: if the conditions are met, the corresponding magnetic cross-section, rotor diameter and number of slots are saved.

[0112] Rotor parameter determination module: Among all the saved magnetic conductive sections, rotor diameters and slot numbers, the magnetic conductive section, rotor diameter and slot number with the smallest excitation loss are selected as the final system parameters.

[0113] The diesel generator harmonic excitation system design device of the present embodiment is used to implement the aforementioned diesel generator harmonic excitation system design method. Therefore, the specific implementation method of the device can be seen in the embodiment part of the basic diesel generator harmonic excitation system design method in the previous text. Therefore, its specific implementation method can refer to the description of the corresponding various parts of the embodiment, which will not be elaborated here.

[0114] In addition, since the diesel generator harmonic excitation system design device of this embodiment is used to implement the aforementioned diesel generator harmonic excitation system design method, its function corresponds to that of the aforementioned method and will not be described in detail here.

[0115] The above disclosure is only a preferred embodiment of the present invention, but the present invention is not limited thereto. Any non-creative changes that can be thought of by a person skilled in the art, as well as several improvements and modifications made without departing from the principle of the present invention, should fall within the protection scope of the present invention.

Claims

1. A diesel generator harmonic excitation system design method, characterized in that: The following steps are involved: Extract the data from the electromagnetic calculation sheet of the diesel generator and calculate the required harmonic excitation rated power; Preset harmonic winding parameters and set the value range of harmonic winding parameters; the harmonic winding parameters include winding current, winding turns and corresponding winding area; Within the range of harmonic winding parameter values, extract the harmonic winding parameters multiple times according to a preset step size to calculate the excitation current; Calculate harmonic excitation power and magnetic circuit saturation based on excitation current; Determine whether the calculated harmonic excitation power meets the harmonic excitation rated power, and if so, save the corresponding magnetic circuit saturation and harmonic winding parameters; Among all the saved magnetic circuit saturations and harmonic winding parameters, the harmonic winding parameter corresponding to the maximum magnetic circuit saturation is selected, and the number of winding turns of the harmonic winding parameter is the number of winding turns of the harmonic excitation system finally determined.

2. The diesel generator harmonic excitation system design method according to claim 1, characterized in that: The winding current ranges from 2 to 4A.

3. The diesel generator harmonic excitation system design method according to claim 1 or 2, characterized in that: The method further comprises the following steps: Determine the number of winding coils according to the number of winding turns; Select winding wire gauge size; Determine the stator slot width and slot depth according to the number of winding turns, the number of winding coils and the winding wire gauge size; The weight and loss of the stator yoke core are determined according to the stator slot width and slot depth.

4. The diesel generator harmonic excitation system design method according to claim 3 is characterized in that: The method further comprises the following steps: Select the rotor diameter and number of slots according to the slot fit, and obtain the magnetic cross section of the rotor teeth; Under the obtained magnetic cross-section conditions, calculate the excitation loss; Determine whether the harmonic excitation power meets the standard under the calculated excitation loss; If the conditions are met, the corresponding magnetic cross section, rotor diameter and number of slots are saved; Among all the saved magnetic conductive cross-sections, rotor diameters and slot numbers, the magnetic conductive cross-section, rotor diameter and slot number with the smallest excitation loss are selected as the final system parameters.

5. A diesel generator harmonic excitation system design device, characterized in that: include, Harmonic excitation rated power calculation module: extract the data in the electromagnetic calculation sheet of the diesel generator and calculate the required harmonic excitation rated power; Harmonic winding parameter preset module: preset harmonic winding parameters and set the value range of harmonic winding parameters; the harmonic winding parameters include winding current, winding turns and corresponding winding area; Excitation current calculation module: within the range of harmonic winding parameter values, the harmonic winding parameters are extracted multiple times according to the preset step length to calculate the excitation current; Power / saturation calculation module: calculates harmonic excitation power and magnetic circuit saturation based on excitation current; The first power judgment module is used to judge whether the calculated harmonic excitation power meets the harmonic excitation rated power. If so, the corresponding magnetic circuit saturation and harmonic winding parameters are saved. Parameter determination module: among all the saved magnetic circuit saturations and harmonic winding parameters, the harmonic winding parameter corresponding to the maximum magnetic circuit saturation is selected, and the number of winding turns of the harmonic winding parameter is the number of winding turns of the harmonic excitation system finally determined.

6. The diesel generator harmonic excitation system design device according to claim 5, characterized in that: The value range of the winding current preset by the harmonic winding parameter preset module is 2 to 4A.

7. The diesel generator harmonic excitation system design device according to claim 6, characterized in that: The device also includes, Winding coil number determination module: determines the number of winding coils according to the number of winding turns; Winding wire gauge size selection module: select winding wire gauge size; Stator slot parameter determination module: determines the stator slot width and slot depth according to the number of winding turns, the number of winding coils and the winding wire gauge size; Stator yoke core determination module: determines the weight and loss of the stator yoke core according to the stator slot width and slot depth.

8. The diesel generator harmonic excitation system design device according to claim 7, characterized in that: The device also includes: Rotor parameter selection module: selects the rotor diameter and number of slots according to the slot matching, and obtains the magnetic cross-section of the rotor teeth; Excitation loss calculation module: calculate the excitation loss under the obtained magnetic cross-section conditions; The second power judgment module is used to judge whether the harmonic excitation power meets the standard under the calculated excitation loss; Rotor parameter saving module: if the conditions are met, the corresponding magnetic cross section, rotor diameter and number of slots are saved; Rotor parameter determination module: Among all the saved magnetic conductive sections, rotor diameters and slot numbers, the magnetic conductive section, rotor diameter and slot number with the smallest excitation loss are selected as the final system parameters.

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