Method and device for acquiring main loop parameters of half-bridge sub-module type direct-current energy consumption device

Abstract

The invention provides a main loop parameter acquisition method and device for a half-bridge sub-module type direct current energy consumption device, and relates to the field of fault ride-through of an offshore wind power flexible direct current system, and the method comprises the steps: determining a resistor model according to the resistance value and resistance energy tolerance of a centralized unloading resistor; an IGCT model and a diode model are determined according to the direct current voltage peak value and the current peak value corresponding to the half-bridge sub-module; according to the rated direct-current voltage and the actual working withstand voltage of the direct-current power transmission system corresponding to the half-bridge sub-module type direct-current energy consumption device, the final set number corresponding to the half-bridge sub-modules is determined by combining a preset half-bridge sub-module redundancy rate; and obtaining an average current value corresponding to the half-bridge sub-module, and determining the capacitance value of the sub-module capacitor according to the average current value, the maximum period of input and quit corresponding to the half-bridge sub-module and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module so as to determine the capacitor model. By adopting the modular structure, the voltage change rate is reduced, and the performance of the energy consumption device is improved.

Description

Technical Field

[0001] The present application relates to the field of fault ride-through of an offshore wind power flexible direct current system, and in particular to a method and device for acquiring main circuit parameters of a half-bridge submodule type direct current energy consuming device. Background Art

[0002] For offshore wind farms connected to the grid via flexible direct current transmission, when a fault occurs in the receiving grid, the active power that the grid-side converter can deliver to the grid decreases, while the active power transmitted by the wind farm-side converter remains unchanged. The system generates surplus power, which causes the DC voltage on the DC line to rise rapidly, affecting the safe operation of the system. The current main option is to install a DC energy dissipation device to ensure the safe operation of the system when the receiving grid fails. Traditional DC energy dissipation devices use power devices directly connected in series, which has problems such as difficulty in voltage equalization of switching devices and large DC voltage fluctuations.

[0003] The power device series valve section is replaced by a switch valve group composed of half-bridge sub-modules in series. The modular structure reduces the voltage change rate and improves the performance of the energy dissipation device. In the application of this solution, it is necessary to reasonably set the various parameters of the main circuit of the corresponding half-bridge sub-module DC energy dissipation device. Therefore, the optimization setting of the main circuit parameters of the half-bridge sub-module DC energy dissipation device is an urgent problem to be solved. Summary of the invention

[0004] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, one purpose of the present application is to propose a method for obtaining the main circuit parameters of a half-bridge sub-module type DC energy consumption device, wherein the half-bridge sub-module type DC energy consumption device is composed of a plurality of half-bridge sub-modules cascaded and connected in series with a centralized unloading resistor, and each half-bridge sub-module includes two insulated gate controlled thyristors IGCT, two diodes and a sub-module capacitor. The method includes: obtaining the centralized unloading resistor resistance value and the resistor energy tolerance corresponding to the half-bridge sub-module type DC energy consumption device, and determining the resistor model according to the centralized unloading resistor resistance value and the resistor energy tolerance; obtaining the current peak value corresponding to the half-bridge sub-module according to the target resistor resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the on-off period, and determining the IGCT model and the diode model according to the DC voltage peak value and the current peak value. ; Determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consuming device and the actual working withstand voltage, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with the preset half-bridge sub-module redundancy rate; obtain the average current value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistor model, the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consuming device and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

[0006] The second objective of the present application is to provide a main circuit parameter acquisition device for a half-bridge sub-module type DC energy consumption device.

[0007] The third objective of the present application is to provide an electronic device.

[0008] A fourth object of the present application is to provide a non-transitory computer-readable storage medium.

[0009] A fifth object of the present application is to provide a computer program product.

[0010] To achieve the above-mentioned purpose, the first embodiment of the present application proposes a method for obtaining the main circuit parameters of a half-bridge sub-module type DC energy consumption device, wherein the half-bridge sub-module type DC energy consumption device is composed of a plurality of half-bridge sub-modules cascaded and connected in series with a centralized unloading resistor, and each half-bridge sub-module includes two insulated gate controlled thyristors IGCT, two diodes and a sub-module capacitor, characterized in that the method comprises: obtaining the centralized unloading resistor resistance value and the resistor energy tolerance corresponding to the half-bridge sub-module type DC energy consumption device, and determining the resistor model according to the centralized unloading resistor resistance value and the resistor energy tolerance; obtaining the current peak value corresponding to the half-bridge sub-module according to the target resistor resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the initiation and deactivation period, and determining the IGCT model and Diode model; determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consuming device and the actual working withstand voltage, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with the preset half-bridge sub-module redundancy rate; obtain the average current value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistor model, the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consuming device and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

[0011] To achieve the above-mentioned purpose, the second embodiment of the present application proposes a main circuit parameter acquisition device for a half-bridge sub-module type DC energy consumption device, including: a first setting module, used to obtain the resistance value and resistance energy tolerance of a centralized unloading resistor corresponding to the half-bridge sub-module type DC energy consumption device, and determine the resistor model according to the resistance value and resistance energy tolerance of the centralized unloading resistor;

[0012] The second setting module is used to obtain the current peak value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the switching period, and determine the IGCT model and the diode model according to the DC voltage peak value and the current peak value;

[0013] A third setting module is used to determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage and the actual working withstand voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with a preset half-bridge sub-module redundancy rate;

[0014] The fourth setting module is used to obtain the average current value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistance model, the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

[0015] To achieve the above-mentioned purpose, the third aspect embodiment of the present application proposes an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to implement the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device as described in the first aspect embodiment of the present application.

[0016] To achieve the above-mentioned purpose, the fourth aspect embodiment of the present application proposes a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to implement the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device as described in the first aspect embodiment of the present application.

[0017] To achieve the above-mentioned purpose, the fifth aspect embodiment of the present application proposes a computer program product, including a computer program, which, when executed by a processor, implements the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device as described in the first aspect embodiment of the present application.

[0018] The present application achieves at least the following beneficial effects: the present application replaces the series valve section of the power device with a switch valve group composed of half-bridge sub-modules in series, adopts a modular structure to reduce the voltage change rate, and improves the performance of the energy consuming device. The proposed method for setting the main circuit parameters of the half-bridge sub-module type DC energy consuming device can realize the optimized setting of the main circuit parameters of the half-bridge sub-module type DC energy consuming device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 It is a schematic diagram of an exemplary implementation of a method for acquiring main circuit parameters of a half-bridge sub-module type DC energy consumption device shown in the present application.

[0021] Figure 2 It is a schematic diagram of the topological structure of a half-bridge sub-module type DC energy consumption device shown in the present application.

[0022] Figure 3It is a schematic diagram of a main circuit parameter acquisition device of a half-bridge sub-module type DC energy consumption device shown in the present application.

[0023] Figure 4 It is a schematic diagram of an electronic device shown in one embodiment of the present application.

[0024] Figure 5 It is a schematic diagram of another main circuit parameter acquisition device of a half-bridge sub-module type DC energy consumption device shown in the present application. DETAILED DESCRIPTION

[0025] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0026] Figure 1 is a schematic diagram of an exemplary implementation of a method for obtaining main circuit parameters of a half-bridge sub-module type DC energy consumption device shown in the present application, such as Figure 1 As shown, the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device includes the following steps:

[0027] S101, obtaining a centralized unloading resistor value and a resistor energy tolerance corresponding to a half-bridge sub-module type DC energy dissipation device, and determining a resistor model according to the centralized unloading resistor value and the resistor energy tolerance.

[0028] Figure 2 is a schematic diagram of the topological structure of a half-bridge submodule type DC energy consumption device shown in the present application, such as Figure 2 As shown, the half-bridge sub-module type DC energy dissipation device is composed of multiple half-bridge sub-modules cascaded, and the last half-bridge sub-module is connected in series with a centralized unloading resistor. Each half-bridge sub-module includes two insulated gate controlled thyristors IGCT as main switching devices T1 and T2, two diodes D1 and D2 are reversely connected in parallel at both ends of the IGCT, and a sub-module capacitor, whose capacitance value is C sm , the centralized unloading resistor is R.

[0029] In the present application, the scheme is mainly used to determine the parameters of each component of the main circuit of the half-bridge sub-module type DC energy consumption device.

[0030] First, the centralized unloading resistor value corresponding to the half-bridge submodule type DC energy dissipation device is obtained, wherein the calculation formula corresponding to the centralized unloading resistor value is:

[0031]

[0032] In the above formula, R represents the resistance of the centralized unloading resistor, U R represents the average operating voltage of the centralized unloading resistor, P represents the rated capacity of the centralized unloading resistor, where U R =k1U, k1 represents the voltage margin coefficient of the energy dissipation resistor, and U represents the rated DC voltage of the half-bridge sub-module type DC energy dissipation device corresponding to the DC transmission system.

[0033] Among them, k1 can be set according to actual conditions.

[0034] Furthermore, the calculation formula corresponding to the resistance energy tolerance is:

[0035] Q=PT max K

[0036] In the above formula, Q represents the resistance energy tolerance, P represents the rated capacity of the centralized unloading resistor, and T max It indicates the maximum continuous operation time of the DC energy consumption device, and K indicates the energy margin coefficient.

[0037] Furthermore, when determining the resistor model based on the centralized unloading resistor resistance value and the resistor energy tolerance, a first mapping relationship between the pre-stored candidate centralized unloading resistor resistance value, the candidate resistor energy tolerance and the candidate resistor model is obtained; based on the centralized unloading resistor resistance value and the resistor energy tolerance, the first mapping relationship is queried to determine the resistor model.

[0038] S102, according to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the switching on and off period, obtain the current peak value corresponding to the half-bridge sub-module, and determine the IGCT model and the diode model according to the DC voltage peak value and the current peak value.

[0039] According to the resistor model selected above, the resistance value corresponding to the selected resistor model is obtained as the target resistance value. In the energy consumption mode, the discharge current needs to flow through T2 in the submodule, and the calculation formula corresponding to the current peak is:

[0040] I max =U dcmax / R1

[0041] In the above formula, I max Indicates the peak current, U dc max It represents the DC voltage peak value corresponding to the half-bridge submodule type DC energy consumption device during the switching period, R1 represents the target resistance value corresponding to the resistor model, where U dc max =k2U, k2 is the IGCT overvoltage margin coefficient, and U represents the rated DC voltage of the half-bridge sub-module type DC energy consumption device corresponding to the DC transmission system.

[0042] Furthermore, the IGCT model is determined based on the DC voltage peak and current peak. Specifically, a second mapping relationship between pre-stored IGCT tolerance current level parameters, IGCT voltage level and candidate IGCT models is obtained, and the second mapping relationship is queried based on the DC voltage peak and current peak to determine the IGCT model.

[0043] For example, if I is calculated max It is 1318A. According to the current situation, the power device of the submodule can be selected as a 3300V / 1500A welding type power device or a 4500V / 2000A crimping type insulated gate bipolar transistor.

[0044] Furthermore, since the diode is anti-parallel connected to the main switching device, the voltage parameters are consistent with the main switching device, so the diode model is determined based on the DC voltage peak and current peak. Specifically: obtain the third mapping relationship between the pre-stored diode tolerance current level parameters, the diode voltage level and the candidate diode model, and query the third mapping relationship based on the DC voltage peak and current peak to determine the diode model.

[0045] S103, determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage and the actual working withstand voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with the preset half-bridge sub-module redundancy rate.

[0046] After the IGCT model is selected, the actual working withstand voltage of the selected IGCT model is determined. Specifically, a list of the relationship between the IGCT model and the actual working withstand voltage of the switch device can be pre-stored in the database, so that the actual working withstand voltage value of the switch device can be matched from the list according to the IGCT model. The actual working withstand voltage value of the switch device can also be determined in advance according to the IGCT model and saved, so that it can be directly obtained from the saved location when executing this step.

[0047] According to the rated DC voltage and actual working withstand voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy dissipation device, the corresponding setting quantity of the half-bridge sub-module is determined, wherein the corresponding setting quantity of the half-bridge sub-module should meet the following requirements:

[0048]

[0049] In the above formula, N represents the number of half-bridge submodules, U represents the rated DC voltage of the DC transmission system corresponding to the half-bridge submodule type DC energy consumption device, and U r Indicates the actual working withstand voltage corresponding to the IGCT model.

[0050] In the present application, the lower limit value of the number of half-bridge sub-modules is obtained as the most basic number of half-bridge sub-modules to minimize the configuration cost of the device.

[0051] Furthermore, a preset half-bridge sub-module redundancy rate is obtained, and the redundant number corresponding to the half-bridge sub-module is determined based on the set number lower limit value combined with the preset half-bridge sub-module redundancy rate, and the sum of the lower limit value of the set number of half-bridge sub-modules and the redundant number is used as the final set number corresponding to the half-bridge sub-module.

[0052] For example, assuming that the redundancy rate is 10%, the lower limit of the number of half-bridge sub-modules is 20:

[0053] 1. Redundancy rate R = 10% = 0.1

[0054] 2. Number of half-bridge submodules N = 20

[0055] 3. Redundancy number C = ceil (0.1 * 20) = 2

[0056] 4.Total number of modules M = C + N = 2 + 20 = 22

[0057] Therefore, according to the set redundancy rate and the number of half-bridge sub-modules, the number of redundant modules is 2 and the total number of modules is 22.

[0058] S104, according to the target resistance value corresponding to the resistance model, the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, obtain the average current value corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

[0059] According to the target resistance value corresponding to the resistor model, the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, the average current value corresponding to the half-bridge sub-module is obtained, where the calculation formula of the average current value is:

[0060]

[0061] In the above formula, I sm It represents the average current value flowing through the half-bridge submodule, corresponding to the most serious fault. U represents the rated DC voltage of the DC transmission system corresponding to the half-bridge submodule type DC energy consumption device. ΔU sm It represents the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and R1 represents the target resistance value corresponding to the resistor model.

[0062] The peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module can be determined based on existing power module switching test data.

[0063] Furthermore, the capacitance value of the submodule capacitor is determined according to the average current value, the maximum cycle of the input and output of the half-bridge submodule and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge submodule. The setting of the capacitance value should satisfy:

[0064]

[0065] In the above formula, C sm Indicates the capacitance value of the submodule capacitor, I sm represents the average current value flowing through the half-bridge submodule, ΔT represents the maximum cycle of the half-bridge submodule, ΔU sm It represents the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, wherein the maximum cycle of the input and output corresponding to the half-bridge sub-module is determined by the allowable temperature rise of the switching device within one working cycle.

[0066] In the present application, a certain margin is taken into consideration, the lower limit value of the DC capacitor is rounded up, the obtained value is used as the capacitance value of the submodule capacitor, and the capacitor model is determined based on the capacitance value.

[0067] The present application replaces the series valve section of the power device with a switch valve group composed of half-bridge sub-modules in series, adopts a modular structure to reduce the voltage change rate and improve the performance of the energy consuming device. The proposed method for setting the main circuit parameters of the half-bridge sub-module type DC energy consuming device can realize the optimized setting of the main circuit parameters of the half-bridge sub-module type DC energy consuming device.

[0068] Figure 3 is a schematic diagram of a main circuit parameter acquisition device of a half-bridge sub-module type DC energy consumption device shown in the present application, such as Figure 3 As shown, the main circuit parameter acquisition device 300 of the half-bridge sub-module type DC energy consumption device includes:

[0069] The first setting module 301 is used to obtain the resistance value and resistance energy tolerance of the centralized unloading resistor corresponding to the half-bridge sub-module type DC energy consumption device, and determine the resistor model according to the resistance value and resistance energy tolerance of the centralized unloading resistor.

[0070] The second setting module 302 is used to obtain the current peak value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the on-off period, and determine the IGCT model and the diode model according to the DC voltage peak value and the current peak value.

[0071] The third setting module 303 is used to determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage and the actual working withstand voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with the preset half-bridge sub-module redundancy rate.

[0072] The fourth setting module 304 is used to obtain the average current value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistance model, the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

[0073] In order to implement the above embodiment, the present application embodiment also proposes an electronic device 400, such as Figure 4 As shown, the electronic device 400 includes: a processor 401 and a memory 402 that is communicatively connected to the processor, the memory 402 stores instructions that can be executed by at least one processor, and the instructions are executed by at least one processor 401 to implement the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device as shown in the above embodiment.

[0074] Furthermore, Figure 5 is a schematic diagram of another main circuit parameter acquisition device of a half-bridge sub-module type DC energy consumption device shown in the present application, such as Figure 5 As shown, the main circuit parameter acquisition device of the half-bridge submodule type DC energy consumption device includes:

[0075] The memory includes memory 1 and memory 2.

[0076] Memory 1 is used to store processor instructions; wherein the instructions are used to implement a method for setting the main circuit parameters of a half-bridge sub-module type DC energy consumption device, including the selection of a centralized unloading resistor, the selection of a main switching device IGCT and a rectifier diode, the setting of the number of half-bridge sub-modules, and the setting of the capacitance value of the half-bridge sub-module.

[0077] Memory 2 stores parameters that need to be preset, including the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module DC energy dissipation device, the voltage margin coefficient of the energy dissipation resistor, the rated capacity of the centralized unloading resistor, the energy margin coefficient, the maximum continuous input time of the energy dissipation device, the overvoltage margin coefficient, the redundancy rate, the resistance value of the candidate centralized unloading resistor, the first mapping relationship between the energy tolerance of the candidate resistor and the candidate resistor model, the IGCT tolerance current level parameter, the second mapping relationship between the IGCT voltage level and the candidate IGCT model, the diode tolerance current level parameter, the third mapping relationship between the diode voltage level and the candidate diode model, the allowable temperature rise of the switching device, and the power module input and output test data.

[0078] The processor includes a first setting module, a second setting module, a third setting module, and a fourth setting module.

[0079] The first setting module is used to obtain the centralized unloading resistor value and the resistor energy tolerance corresponding to the half-bridge sub-module type DC energy dissipation device, and determine the resistor model according to the centralized unloading resistor value and the resistor energy tolerance.

[0080] The second setting module is used to obtain the current peak value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the operation period, and determine the IGCT model and the diode model according to the DC voltage peak value and the current peak value.

[0081] The third setting module is used to determine the actual working tolerance voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage and the actual working tolerance voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with the preset half-bridge sub-module redundancy rate.

[0082] The fourth setting module is used to obtain the average current value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistance model, the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

[0083] The first setting module includes a first acquisition unit, which receives and executes the energy dissipation resistor selection instruction from the memory 1, firstly acquires the rated DC voltage U, the energy dissipation resistor voltage margin coefficient k1 and the centralized unloading resistor rated capacity P of the half-bridge sub-module type DC energy dissipation device corresponding to the DC power transmission system pre-stored in the memory 2, and the first calculation unit calculates the centralized unloading resistor resistance according to the following formula:

[0084] R=(k1U) 2 / P

[0085] The value is returned to the memory 2, and the first setting unit sets the unloading resistor value according to the calculated unloading resistor value. Then, the first acquisition unit acquires the energy margin coefficient K and the maximum continuous input time T of the energy consumption device from the memory 2. max , the second calculation unit calculates the resistance energy tolerance according to the following formula:

[0086] Q=PT max K

[0087] The second setting unit searches for a match in the first mapping relationship between the candidate centralized unloading resistor values, the candidate resistor energy tolerance and the candidate resistor models pre-stored in the memory 2 according to the centralized unloading resistor resistance value and the resistor energy tolerance, determines the optimal resistor selection closest to the calculated value, and determines the target resistor value corresponding to the selected resistor model.

[0088] The second setting module includes a second acquisition unit, which receives and executes the main switch device IGCT and the rectifier diode selection instruction from the memory 1, obtains the rated DC voltage U of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device pre-stored in the memory 2, the IGCT overvoltage margin coefficient k2 and the target resistance value R1 returned to the memory 2 by the second setting unit, and the third calculation unit calculates the discharge current peak value according to the following formula:

[0089] I max =k2U / R1

[0090] The third setting unit searches for a match in the second mapping relationship between the IGCT withstand current level parameter, the IGCT voltage level and the candidate IGCT model pre-stored in the memory 2 according to the calculated value, obtains the closest optimal IGCT selection, and sets the actual working withstand voltage U of the matched switching device to r The value is returned to the memory 2. Since the diode is anti-parallel connected to the main switch device, the voltage parameter is consistent with the main switch device, and the third setting unit determines the diode model according to the third mapping relationship between the diode withstand current level parameter, the diode voltage level and the candidate diode model pre-stored in the memory 2 according to the calculated value.

[0091] The third setting module includes a third acquisition unit, which receives and executes the half-bridge sub-module number setting instruction from the memory 1, obtains the system rated DC voltage U and the actual working withstand voltage U of the switching device returned by the third setting unit to the memory 2. r , the fourth calculation unit calculates the lower limit of the number of half-bridge sub-modules according to the following formula:

[0092]

[0093] The fourth setting unit sets the number of half-bridge submodules according to the lower limit value. Then, the third acquisition unit acquires the set redundancy rate from the memory 2, the fifth calculation unit calculates the redundant number of the half-bridge submodules according to the redundancy rate and the number of the set half-bridge submodules, rounds up the product of the redundancy rate and the number of the set half-bridge submodules, takes the obtained value as the redundant number, and sums the redundant number and the number of the set half-bridge submodules, and the fifth setting unit sets the total number of the half-bridge submodules according to the total number obtained by the fifth calculation unit.

[0094] The fourth setting module includes a fourth acquisition unit, which receives and executes the submodule capacitance value setting instruction from the memory 1, obtains the system rated voltage U, the target resistance value R1 corresponding to the resistor model, and obtains the peak value ΔU of the power module capacitance voltage fluctuation peak according to the power module input and output test data stored in the memory 2 sm The sixth calculation unit calculates the average current value I flowing through each power module when the most serious fault occurs according to the following formula: sm ,

[0095]

[0096] Then, the fourth acquisition unit determines the maximum period ΔT allowed for the power module to be put into operation and withdrawn according to the corresponding list of the allowable temperature rise of the switching device in one working cycle and the maximum period allowed for the power module to be put into operation and withdrawn stored in the memory 2, and the seventh calculation unit calculates the lower limit value C of the DC capacitance according to the following formula: sm And round up:

[0097]

[0098] The sixth setting unit sets the value of the DC capacitor according to the DC capacitor lower limit value, and determines the capacitor model based on the capacitance value.

[0099] In order to implement the above embodiment, the embodiment of the present application also proposes a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to implement the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device as shown in the above embodiment.

[0100] In order to implement the above embodiment, the embodiment of the present application also proposes a computer program product, including a computer program, which, when executed by a processor, implements the main circuit parameter acquisition method of the half-bridge sub-module type DC energy consumption device as shown in the above embodiment.

[0101] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0102] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0103] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for obtaining main circuit parameters of a half-bridge sub-module type DC energy consumption device, wherein the half-bridge sub-module type DC energy consumption device is formed by cascading multiple half-bridge sub-modules and connecting them in series with a centralized unloading resistor, and each of the half-bridge sub-modules includes two insulated gate controlled thyristors (IGCTs), two diodes and a sub-module capacitor, characterized in that: The method comprises: Obtaining the centralized unloading resistor value and the resistor energy tolerance corresponding to the half-bridge sub-module type DC energy dissipation device, and determining the resistor model according to the centralized unloading resistor value and the resistor energy tolerance; According to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the switching period, the current peak value corresponding to the half-bridge sub-module is obtained, and the IGCT model and the diode model are determined according to the DC voltage peak value and the current peak value; Determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the number of settings corresponding to the half-bridge sub-module according to the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device and the actual working withstand voltage, and determine the final number of settings corresponding to the half-bridge sub-module based on the lower limit of the number of settings combined with a preset half-bridge sub-module redundancy rate; According to the target resistance value corresponding to the resistance model, the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, the average current value corresponding to the half-bridge sub-module is obtained, and according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, the capacitance value of the sub-module capacitor is determined, and the capacitor model is determined based on the capacitance value.

2. The method according to claim 1, characterized in that The calculation formula corresponding to the resistance value of the centralized unloading resistor is: R=U R 2 / P In the above formula, R represents the resistance of the centralized unloading resistor, U R represents the average operating voltage of the centralized unloading resistor, P represents the rated capacity of the centralized unloading resistor, where U R =k1U, k1 represents the voltage margin coefficient of the energy dissipation resistor, and U represents the rated DC voltage of the half-bridge sub-module type DC energy dissipation device corresponding to the DC transmission system.

3. The method according to claim 2, characterized in that The calculation formula corresponding to the resistance energy tolerance is: Q=PT max K In the above formula, Q represents the resistance energy tolerance, P represents the rated capacity of the centralized unloading resistor, and T max It represents the longest continuous input time of the half-bridge submodule type DC energy consumption device, and K represents the energy margin coefficient.

4. The method according to claim 3, characterized in that The determining of the resistor model according to the resistance value of the centralized unloading resistor and the resistor energy tolerance includes: Acquire a pre-stored first mapping relationship between candidate centralized unloading resistor values, candidate resistor energy tolerance, and candidate resistor models; Based on the resistance value of the centralized unloading resistor and the energy tolerance of the resistor, the first mapping relationship is queried to determine the resistor model.

5. The method according to claim 1 or 4, characterized in that: According to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the switching period, the current peak value corresponding to the half-bridge sub-module is obtained, and the calculation formula corresponding to the current peak value is: I max =U dcmax / R1 In the above formula, I max Indicates the current peak value corresponding to the half-bridge submodule, U dcmax represents the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the switching period, R1 represents the target resistance value corresponding to the resistor model, wherein U dcmax =k2U, k2 is the IGCT overvoltage margin coefficient, and U represents the rated DC voltage of the half-bridge sub-module type DC energy consumption device corresponding to the DC transmission system.

6. The method according to claim 5, characterized in that The determining of the IGCT model and the diode model according to the DC voltage peak value and the current peak value includes: Acquire a second mapping relationship between a pre-stored IGCT withstand current level parameter, an IGCT voltage level, and a candidate IGCT model; Acquire a third mapping relationship between a pre-stored diode withstand current level parameter, a diode voltage level, and a candidate diode model; querying the second mapping relationship according to the DC voltage peak value and the current peak value to determine the IGCT model; The third mapping relationship is queried according to the DC voltage peak value and the current peak value to determine the diode model.

7. The method according to claim 6, characterized in that In determining the lower limit of the number of settings corresponding to the half-bridge sub-modules according to the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device and the actual working withstand voltage, the number of settings corresponding to the half-bridge sub-modules should satisfy: In the above formula, N represents the number of half-bridge submodules, N is a natural number greater than 0, U represents the rated DC voltage of the DC transmission system corresponding to the half-bridge submodule type DC energy consumption device, U r Indicates the actual working withstand voltage corresponding to the IGCT model.

8. The method according to claim 6, characterized in that According to the target resistance value corresponding to the resistor model, the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, the average current value corresponding to the half-bridge sub-module is obtained, and the calculation formula of the average current value is: In the above formula, I sm represents the average current value flowing through the half-bridge submodule, U represents the rated DC voltage of the DC transmission system corresponding to the half-bridge submodule type DC energy consumption device, ΔU sm represents the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and R1 represents the target resistance value corresponding to the resistor model.

9. The method according to claim 8, characterized in that In determining the capacitance value of the submodule capacitor according to the average current value, the maximum cycle of the input and output corresponding to the half-bridge submodule, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge submodule, the capacitance value is calculated by the formula: In the above formula, C sm represents the capacitance value of the submodule capacitor, I sm represents the average current value flowing through the half-bridge submodule, ΔT represents the maximum input and output cycle corresponding to the half-bridge submodule, ΔU sm It represents the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, wherein the maximum cycle of the input and output corresponding to the half-bridge sub-module is determined by the temperature rise allowed by the switching device within one working cycle.

10. A main circuit parameter acquisition device for a half-bridge submodule type DC energy consumption device, characterized in that: include: A first setting module is used to obtain the resistance value and resistance energy tolerance of the centralized unloading resistor corresponding to the half-bridge sub-module type DC energy consumption device, and determine the resistor model according to the resistance value and the resistance energy tolerance of the centralized unloading resistor; The second setting module is used to obtain the current peak value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistor model and the DC voltage peak value corresponding to the half-bridge sub-module type DC energy consumption device during the switching period, and determine the IGCT model and the diode model according to the DC voltage peak value and the current peak value; A third setting module is used to determine the actual working withstand voltage corresponding to the IGCT model, determine the lower limit of the setting quantity corresponding to the half-bridge sub-module according to the rated DC voltage of the DC power transmission system corresponding to the half-bridge sub-module type DC energy consumption device and the actual working withstand voltage, and determine the final setting quantity corresponding to the half-bridge sub-module based on the lower limit of the setting quantity combined with a preset half-bridge sub-module redundancy rate; The fourth setting module is used to obtain the average current value corresponding to the half-bridge sub-module according to the target resistance value corresponding to the resistance model, the rated DC voltage of the DC transmission system corresponding to the half-bridge sub-module type DC energy consumption device, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitance value of the sub-module capacitor according to the average current value, the maximum cycle of input and output corresponding to the half-bridge sub-module, and the peak value of the capacitor voltage fluctuation peak corresponding to the half-bridge sub-module, and determine the capacitor model based on the capacitance value.

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