A method and device for setting parameters of a main loop of a distributed direct current energy consumption device

Abstract

The present application relates to offshore wind power DC transmission technology field, disclose a kind of distributed DC energy consumption device main circuit parameter setting method and device.The present application with the ratio of the rated voltage of distributed DC energy consumption device corresponding DC transmission system and power module long-term average voltage as the lower limit value of power module quantity, the quantity of power module is set according to the value;According to the rated voltage, rated power and margin coefficient of system, and total module number, calculate the upper limit value of energy consumption resistance, and the value of energy consumption resistance is set according to the value;The average current value of each power module is calculated when the most serious fault occurs, and the maximum cycle of allowing power module to be put into and withdrawn is set, and the ratio of the product of average current value and maximum cycle and the peak value of power module capacitor voltage fluctuation peak is used as the lower limit value of DC capacitor, and the value of the DC capacitor is set according to the value.The present application can quickly realize the optimization setting of the main circuit parameter of DC energy consumption device based on distributed scheme.

Description

Technical Field

[0001] This invention relates to the field of offshore wind power DC transmission technology, and in particular to a method and apparatus for setting the main circuit parameters of a distributed DC energy consumption device. Background Technology

[0002] For offshore wind power flexible DC transmission systems, when a fault occurs in the AC grid at the receiving end, the output power of the converter station at the receiving end will decrease. Since the power of the wind farm is difficult to respond quickly, if the surplus power is maintained, the DC voltage will continue to rise until the system trips.

[0003] DC power dissipation devices are crucial physical components for fault ride-through in the event of an AC grid failure at the receiving end. Currently proposed DC power dissipation devices can be broadly categorized into three types based on their main circuit structure: centralized, distributed, and semi-centralized. Centralized devices employ a series-connected valve power dissipation circuit, where numerous switching devices are directly connected in series. Distributed devices utilize modular distributed power dissipation resistor circuits, avoiding the direct series connection of numerous switching devices, with power dissipation resistors distributed within each module. Semi-centralized devices employ a modular multilevel converter-type centralized power dissipation resistor circuit.

[0004] Distributed solutions are currently the primary approach for DC energy-consuming devices in practical engineering applications. During the application of this distributed solution, it is necessary to rationally configure the various parameters of the main circuit of the distributed DC energy-consuming device. Therefore, a method is needed to quickly optimize the parameters of the main circuit of the distributed DC energy-consuming device. Summary of the Invention

[0005] This invention provides a method and apparatus for setting the main circuit parameters of a distributed DC energy-consuming device, solving the technical problem of how to quickly optimize the setting of the main circuit parameters of a distributed DC energy-consuming device.

[0006] The first aspect of this invention provides a method for setting the main circuit parameters of a distributed DC energy-consuming device. The distributed DC energy-consuming device is composed of multiple cascaded power modules. Each power module includes a mechanical switch, a first diode, a second diode, a DC capacitor, a unidirectional power electronic switch, and an energy-consuming resistor. One end of the mechanical switch, the cathode of the first diode, and the anode of the second diode are connected. The other end of the mechanical switch, the anode of the first diode, and one end of the energy-consuming resistor are connected to the cathode of the DC capacitor. The cathode of the second diode, the collector of the unidirectional power electronic switch, and the anode of the unidirectional power electronic switch are connected to the anode of the DC capacitor. The emitter of the unidirectional power electronic switch and the other end of the energy-consuming resistor are connected. The method includes:

[0007] The long-term average voltage of the power module is determined based on the voltage level of the switching devices of the power module. The rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device is obtained. The ratio of the rated voltage to the long-term average voltage is used as the lower limit of the number of power modules. The number of power modules is set according to the lower limit of the number of power modules.

[0008] Determine the redundancy of the power modules, determine the total number of modules based on the set number of power modules and the redundancy, obtain the rated power and margin coefficient of the corresponding DC transmission system, calculate the upper limit value of the energy consumption resistor based on the rated voltage, the total number of modules, the rated power and the margin coefficient, and set the value of the energy consumption resistor based on the upper limit value of the energy consumption resistor;

[0009] Determine the peak value of the voltage fluctuation peak of the power module capacitor. Calculate the average current value flowing through each power module when the most severe fault occurs based on the peak value, the rated voltage, and the set value of the energy-consuming resistor. Set the maximum period during which the power module can be put into and taken out of the system. Use the ratio of the product of the average current value and the maximum period to the peak value as the lower limit value of the DC capacitor. Set the value of the DC capacitor based on the lower limit value of the DC capacitor.

[0010] According to one aspect of the invention, determining the redundancy of the power module includes:

[0011] Set the redundancy rate of the power module;

[0012] The redundancy of the power modules is calculated based on the redundancy rate and the number of power modules configured.

[0013] According to one achievable method of the first aspect of the present invention, setting the redundancy rate of the power module includes:

[0014] The redundancy rate should be set to a value within 10%.

[0015] According to one achievable method of the first aspect of the present invention, obtaining the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device includes:

[0016] When the corresponding DC transmission system adopts a symmetrical single-pole connection, the voltage between the corresponding poles is obtained as the rated voltage; when the corresponding DC transmission system adopts a symmetrical double-pole connection, the voltage between the corresponding pole and ground is obtained as the rated voltage; when the corresponding DC transmission system adopts a high-low valve group connection, the DC voltage of the corresponding single valve group is obtained as the rated voltage.

[0017] And, obtaining the rated power of the corresponding DC transmission system includes:

[0018] When the corresponding DC transmission system adopts a symmetrical single-pole connection, the power between the corresponding poles is obtained as the rated power; when the corresponding DC transmission system adopts a symmetrical double-pole connection, the power between the corresponding pole and ground is obtained as the rated power; when the corresponding DC transmission system adopts a high-low valve group connection, the power of the corresponding single valve group is obtained as the rated power.

[0019] According to one aspect of the invention, the calculation of the upper limit value of the energy-consuming resistance based on the rated voltage, the total number of modules, the rated power, and the margin factor includes:

[0020] The upper limit value of the energy-consuming resistor is calculated using the following formula:

[0021]

[0022] In the formula, R max U represents the upper limit of the energy-consuming resistor. N The rated voltage is N, k is the margin factor, and N is the zero-tolerance ratio. total P represents the total number of modules. N The rated power is [the power rating].

[0023] According to a method achievable according to a first aspect of the invention, calculating the average current flowing through each power module when the most severe fault occurs, based on the peak value, the rated voltage, and the value of the set energy-consuming resistor, includes:

[0024] The average current flowing through each power module during the most severe fault is calculated using the following formula:

[0025]

[0026] In the formula, I sm ΔU represents the average current flowing through each power module when the most severe fault occurs. sm For the peak value, U N R is the rated voltage, and R is the value of the set energy-consuming resistor.

[0027] According to one aspect of the present invention, setting the number of power modules according to the lower limit value of the number of power modules includes:

[0028] The number of power modules is defined as the lower limit of the number of power modules.

[0029] Setting the value of the energy-consuming resistor according to the upper limit value of the energy-consuming resistor includes:

[0030] The upper limit value of the energy-consuming resistor is taken as the value of the energy-consuming resistor;

[0031] And / or, setting the value of the DC capacitor according to the lower limit value of the DC capacitor includes:

[0032] The lower limit value of the DC capacitor is used as the value of the DC capacitor.

[0033] A second aspect of the present invention provides a main circuit parameter setting device for a distributed DC energy dissipation device. The distributed DC energy dissipation device is composed of multiple cascaded power modules. Each power module includes a mechanical switch, a first diode, a second diode, a DC capacitor, a unidirectional power electronic switch, and an energy-dissipating resistor. One end of the mechanical switch, the cathode of the first diode, and the anode of the second diode are connected. The other end of the mechanical switch, the anode of the first diode, and one end of the energy-dissipating resistor are connected to the cathode of the DC capacitor. The cathode of the second diode, the collector of the unidirectional power electronic switch, and the anode of the unidirectional power electronic switch are connected to the anode of the DC capacitor. The emitter of the unidirectional power electronic switch and the other end of the energy-dissipating resistor are connected. The device includes:

[0034] The first setting module is used to determine the long-term average voltage of the power module according to the voltage level of the switching device of the power module, obtain the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device, use the ratio of the rated voltage to the long-term average voltage as the lower limit value of the number of power modules, and set the number of power modules according to the lower limit value of the number of power modules.

[0035] The second setting module is used to determine the redundancy of the power modules, determine the total number of modules based on the set number of power modules and the redundancy, obtain the rated power and margin coefficient of the corresponding DC transmission system, calculate the upper limit value of the energy consumption resistor based on the rated voltage, the total number of modules, the rated power and the margin coefficient, and set the value of the energy consumption resistor based on the upper limit value of the energy consumption resistor.

[0036] The third setting module is used to determine the peak value of the voltage fluctuation peak of the power module capacitor, calculate the average current value flowing through each power module when the most serious fault occurs based on the peak value, the rated voltage and the set energy-consuming resistor value, set the maximum period for the power module to be put into and taken out, use the ratio of the product of the average current value and the maximum period to the peak value as the lower limit value of the DC capacitor, and set the value of the DC capacitor based on the lower limit value of the DC capacitor.

[0037] According to one achievable embodiment of the second aspect of the present invention, the second setting module includes:

[0038] The first setting unit is used to set the redundancy rate of the power module;

[0039] The first calculation unit is used to calculate the redundancy of the power modules based on the redundancy rate and the number of power modules configured.

[0040] According to one achievable method of the second aspect of the present invention, the first setting unit is specifically used for:

[0041] The redundancy rate should be set to a value within 10%.

[0042] According to one achievable embodiment of the second aspect of the present invention, the first setting module includes:

[0043] The first acquisition unit is used to acquire the corresponding inter-pole voltage as the rated voltage when the corresponding DC transmission system adopts a symmetrical single-pole connection; acquire the corresponding pole-to-ground voltage as the rated voltage when the corresponding DC transmission system adopts a symmetrical double-pole connection; and acquire the DC voltage of the corresponding single valve group as the rated voltage when the corresponding DC transmission system adopts a high-low valve group connection.

[0044] And, the second setting module includes:

[0045] The second acquisition unit is used to acquire the corresponding inter-pole power as the rated power when the corresponding DC transmission system adopts a symmetrical single-pole connection; to acquire the corresponding pole-to-ground power as the rated power when the corresponding DC transmission system adopts a symmetrical double-pole connection; and to acquire the power of the corresponding single valve group as the rated power when the corresponding DC transmission system adopts a high-low valve group connection.

[0046] According to one achievable embodiment of the second aspect of the present invention, the second setting module includes:

[0047] The second calculation unit is used to calculate the upper limit value of the energy-consuming resistor according to the following formula:

[0048]

[0049] In the formula, R max U represents the upper limit of the energy-consuming resistor. N The rated voltage is N, k is the margin factor, and N is the zero-tolerance ratio. total P represents the total number of modules. N The rated power is [the power rating].

[0050] According to one achievable embodiment of the second aspect of the present invention, the third setting module includes:

[0051] The third calculation unit is used to calculate the average current flowing through each power module when the most severe fault occurs, according to the following formula:

[0052]

[0053] In the formula, I sm ΔU represents the average current flowing through each power module when the most severe fault occurs. sm For the peak value, U N R is the rated voltage, and R is the value of the set energy-consuming resistor.

[0054] According to one achievable embodiment of the second aspect of the present invention, the first setting module includes:

[0055] The second setting unit is used to set the lower limit value of the number of power modules as the number of power modules;

[0056] The second setting module includes:

[0057] The third setting unit is used to set the upper limit value of the energy-consuming resistor as the value of the energy-consuming resistor;

[0058] And / or, the third setting module includes:

[0059] The fourth setting unit is used to set the lower limit value of the DC capacitor as the value of the DC capacitor.

[0060] A third aspect of the present invention provides a main circuit parameter setting device for a distributed DC energy consumption device, comprising:

[0061] A memory for storing instructions; wherein the instructions are used to implement the method for setting the main circuit parameters of the distributed DC energy consumption device as described in any of the above-mentioned ways;

[0062] A processor for executing instructions in the memory.

[0063] The fourth aspect of the present invention provides a computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, it implements the method for setting the main circuit parameters of a distributed DC energy consumption device as described in any of the above embodiments.

[0064] As can be seen from the above technical solutions, the present invention has the following advantages:

[0065] This invention uses the ratio of the rated voltage of the DC transmission system corresponding to the distributed DC energy dissipation device to the long-term average voltage of the power module as the lower limit value for the number of power modules, and sets the number of power modules according to this lower limit value; calculates the upper limit value of the energy dissipation resistor based on the system's rated voltage, rated power, margin coefficient, and total number of modules, and sets the value of the energy dissipation resistor according to this upper limit value; calculates the average current value flowing through each power module when the most severe fault occurs, sets the maximum allowed period for power module activation and deactivation, and uses the ratio of the product of the average current value and the maximum period to the peak value of the power module capacitor voltage fluctuation as the lower limit value for the DC capacitor, and sets the value of the DC capacitor according to this lower limit value; this invention can quickly realize the optimized setting of the main circuit parameters of the DC energy dissipation device based on the distributed scheme, and the setting method is simple and convenient. Attached Figure Description

[0066] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0067] Figure 1 This is a schematic diagram of the topology of a distributed DC power consumption device;

[0068] Figure 2 A flowchart illustrating a method for setting main circuit parameters of a distributed DC energy consumption device, provided as an optional embodiment of the present invention;

[0069] Figure 3 The diagram below shows the structural connection of a main circuit parameter setting device for a distributed DC energy consumption device, provided as an optional embodiment of the present invention.

[0070] Figure label:

[0071] R-SM1 - First power module; R-SM2 - Second power module; R-SM n - nth power module; S1 - mechanical switch; D1 - first diode D1; D2 - second diode; C - DC capacitor; S2 - unidirectional power electronic switch; R i - Power consumption resistor; 1- First setting module; 2- Second setting module; 3- Third setting module. Detailed Implementation

[0072] This invention provides a method and apparatus for setting the main circuit parameters of a distributed DC energy-consuming device, which solves the technical problem of how to quickly optimize the setting of the main circuit parameters of a DC energy-consuming device based on a distributed scheme.

[0073] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0074] A schematic diagram of the topology of the distributed DC power consumption device targeted by the method and apparatus of this application is shown below. Figure 1 As shown. This distributed DC power consumption device consists of multiple cascaded power modules, for example... Figure 1 As shown, from the first power module R-SM1, the second power module R-SM2 to the nth power module R-SM n They are cascaded together. Each power module includes a mechanical switch S1, a first diode D1, a second diode D2, a DC capacitor C, a unidirectional power electronic switch S2, and a power-consuming resistor R. i One end of the mechanical switch S1, the cathode of the first diode D1, and the anode of the second diode D2 are connected; the other end of the mechanical switch S1, the anode of the first diode D1, and the energy-consuming resistor R are connected. i One end of the diode is connected to the negative terminal of the DC capacitor C. The negative terminal of the second diode D2 and the collector of the unidirectional power electronic switch S2 are connected to the positive terminal of the DC capacitor C. The emitter of the unidirectional power electronic switch S2 and the energy-dissipating resistor R are connected to the positive terminal of the DC capacitor C. i The other end is connected.

[0075] Please see Figure 2 , Figure 2 A flowchart of a method for setting main circuit parameters of a distributed DC energy consumption device according to an embodiment of the present invention is shown.

[0076] The present invention provides a method for setting the main circuit parameters of a distributed DC energy consumption device, including steps S1-S3.

[0077] Step S1: Determine the long-term average voltage of the power module based on the voltage level of the switching devices of the power module, obtain the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device, use the ratio of the rated voltage to the long-term average voltage as the lower limit value of the number of power modules, and set the number of power modules according to the lower limit value of the number of power modules.

[0078] One feasible approach is to pre-store a list of relationships between switching device voltage levels and the long-term average voltage of the power module in a database. This allows the long-term average voltage value of the power module to be matched from the list based on the switching device voltage level. Another feasible approach is to pre-determine and save the long-term average voltage value of the power module based on the switching device voltage level, so that it can be retrieved directly from the saved location during this step. The correspondence between the switching device voltage level and the long-term average voltage of the power module is set according to the actual situation.

[0079] In one feasible manner, obtaining the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device includes:

[0080] When the corresponding DC transmission system adopts a symmetrical single-pole connection, the voltage between the corresponding poles is obtained as the rated voltage; when the corresponding DC transmission system adopts a symmetrical double-pole connection, the voltage between the corresponding pole and ground is obtained as the rated voltage; when the corresponding DC transmission system adopts a high-low valve group connection, the DC voltage of the corresponding single valve group is obtained as the rated voltage.

[0081] The ratio of the rated voltage to the long-term average voltage is used as the lower limit for the number of power modules, which means that the number of power modules installed in a distributed DC energy consumption device should meet the following requirements:

[0082]

[0083] In the formula, N set Indicates the number of power modules installed, U N V represents the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device. ave This is the long-term average voltage of the power module.

[0084] As one feasible approach, the number of power modules can be determined by setting a minimum number of power modules, which can minimize the configuration cost of the device.

[0085] Step S2: Determine the redundancy of the power modules, determine the total number of modules based on the set number of power modules and the redundancy, obtain the rated power and margin coefficient of the corresponding DC transmission system, calculate the upper limit value of the energy dissipation resistor based on the rated voltage, the total number of modules, the rated power and the margin coefficient, and set the value of the energy dissipation resistor based on the upper limit value of the energy dissipation resistor.

[0086] In one feasible manner, determining the redundancy of the power module includes:

[0087] Set the redundancy rate of the power module;

[0088] The redundancy of the power modules is calculated based on the redundancy rate and the number of power modules configured.

[0089] In a specific implementation, the product of the redundancy rate and the number of power modules can be rounded up to obtain the redundancy quantity. Furthermore, the sum of the redundancy capacity and the number of power modules is used as the total number of modules.

[0090] In other feasible methods, the actual redundancy quantity can be determined based on the actual conditions of multiple existing offshore wind power DC transmission systems, and the average / median value of the actual redundancy quantity can be saved so that the value of the redundancy quantity can be directly extracted from the corresponding saved location when the method is executed.

[0091] In one feasible manner, setting the redundancy rate of the power module includes:

[0092] The redundancy rate should be set to a value within 10%.

[0093] In specific implementation methods, a redundancy rate of 5% or 8% is generally adopted.

[0094] In one feasible manner, obtaining the rated power of the corresponding DC transmission system includes:

[0095] When the corresponding DC transmission system adopts a symmetrical single-pole connection, the power between the corresponding poles is obtained as the rated power; when the corresponding DC transmission system adopts a symmetrical double-pole connection, the power between the corresponding pole and ground is obtained as the rated power; when the corresponding DC transmission system adopts a high-low valve group connection, the power of the corresponding single valve group is obtained as the rated power.

[0096] In one feasible method, the upper limit of the energy-consuming resistance is calculated according to the following formula:

[0097]

[0098] In the formula, R max U represents the upper limit of the energy-consuming resistor. N The rated voltage is N, k is the margin factor, and N is the zero-tolerance ratio. total P represents the total number of modules. N The rated power is [the power rating].

[0099] According to this embodiment, the setting value of the energy-consuming resistor should meet the following requirements:

[0100]

[0101] In the formula, R set This is the set value for the energy-consuming resistor.

[0102] Among other possible methods, for The value is rounded down to the nearest integer, and the resulting value is used as the upper limit of the energy-consuming resistor.

[0103] As a specific implementation method, the upper limit value of the energy-consuming resistor is used as the value of the energy-consuming resistor.

[0104] Step S3: Determine the peak value of the voltage fluctuation peak of the power module capacitor. Calculate the average current value flowing through each power module when the most severe fault occurs based on the peak value, the rated voltage, and the set value of the energy-consuming resistor. Set the maximum period during which the power module can be put into and taken out of the system. Use the ratio of the product of the average current value and the maximum period to the peak value as the lower limit value of the DC capacitor. Set the value of the DC capacitor based on the lower limit value of the DC capacitor.

[0105] The peak value of the capacitor voltage fluctuation of the power module can be determined based on existing power module commissioning and decommissioning test data. However, this embodiment does not impose any limitations on this.

[0106] The maximum allowed cycle for power module activation and deactivation is determined by the allowable temperature rise of the switching device within one operating cycle.

[0107] In one feasible approach, the average current flowing through each power module during the most severe fault can be estimated using the following formula:

[0108]

[0109] In the formula, I sm ΔU represents the average current flowing through each power module when the most severe fault occurs. sm For the peak value, U N R is the rated voltage, and R is the value of the set energy-consuming resistor.

[0110] The ratio of the product of the average current value and the maximum period to the peak value is used as the lower limit value of the DC capacitor, that is, the setting value of the DC capacitor should satisfy:

[0111]

[0112] In the formula, C set This indicates the setting value of the DC capacitor, where ΔT is the maximum period.

[0113] In one specific implementation, the lower limit value of the DC capacitor is used as the value of the DC capacitor. In other implementations, considering a certain margin, the lower limit value of the DC capacitor is rounded up, and the resulting value is used as the value of the DC capacitor.

[0114] The present invention also provides a main circuit parameter setting device for a distributed DC energy consumption device, which can be used to execute the main circuit parameter setting method for a distributed DC energy consumption device described in any of the above embodiments of the present invention.

[0115] Please see Figure 3 , Figure 3 The diagram shows a structural connection block diagram of a main circuit parameter setting device for a distributed DC energy consumption device according to an embodiment of the present invention.

[0116] This invention provides a main circuit parameter setting device for a distributed DC energy consumption device, comprising:

[0117] The first setting module 1 is used to determine the long-term average voltage of the power module according to the voltage level of the switching device of the power module, obtain the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device, use the ratio of the rated voltage to the long-term average voltage as the lower limit value of the number of power modules, and set the number of power modules according to the lower limit value of the number of power modules.

[0118] The second setting module 2 is used to determine the redundancy of the power modules, determine the total number of modules based on the set number of power modules and the redundancy, obtain the rated power and margin coefficient of the corresponding DC transmission system, calculate the upper limit value of the energy consumption resistor based on the rated voltage, the total number of modules, the rated power and the margin coefficient, and set the value of the energy consumption resistor based on the upper limit value of the energy consumption resistor.

[0119] The third setting module 3 is used to determine the peak value of the voltage fluctuation peak of the power module capacitor, calculate the average current value flowing through each power module when the most serious fault occurs based on the peak value, the rated voltage and the set energy-consuming resistor value, set the maximum period for power module to be put into and taken out, use the ratio of the product of the average current value and the maximum period to the peak value as the lower limit value of the DC capacitor, and set the value of the DC capacitor based on the lower limit value of the DC capacitor.

[0120] In one feasible implementation, the second setting module 2 includes:

[0121] The first setting unit is used to set the redundancy rate of the power module;

[0122] The first calculation unit is used to calculate the redundancy of the power modules based on the redundancy rate and the number of power modules configured.

[0123] In one feasible implementation, the first setting unit is specifically used for:

[0124] The redundancy rate should be set to a value within 10%.

[0125] In one feasible implementation, the first setting module 1 includes:

[0126] The first acquisition unit is used to acquire the corresponding inter-pole voltage as the rated voltage when the corresponding DC transmission system adopts a symmetrical single-pole connection; acquire the corresponding pole-to-ground voltage as the rated voltage when the corresponding DC transmission system adopts a symmetrical double-pole connection; and acquire the DC voltage of the corresponding single valve group as the rated voltage when the corresponding DC transmission system adopts a high-low valve group connection.

[0127] And, the second setting module 2 includes:

[0128] The second acquisition unit is used to acquire the corresponding inter-pole power as the rated power when the corresponding DC transmission system adopts a symmetrical single-pole connection; to acquire the corresponding pole-to-ground power as the rated power when the corresponding DC transmission system adopts a symmetrical double-pole connection; and to acquire the power of the corresponding single valve group as the rated power when the corresponding DC transmission system adopts a high-low valve group connection.

[0129] In one feasible implementation, the second setting module 2 includes:

[0130] The second calculation unit is used to calculate the upper limit value of the energy-consuming resistor according to the following formula:

[0131]

[0132] In the formula, R max U represents the upper limit of the energy-consuming resistor. N The rated voltage is N, k is the margin factor, and N is the zero-tolerance ratio. total P represents the total number of modules. N The rated power is [the power rating].

[0133] In one feasible implementation, the third setting module 3 includes:

[0134] The third calculation unit is used to calculate the average current flowing through each power module when the most severe fault occurs, according to the following formula:

[0135]

[0136] In the formula, I sm ΔU represents the average current flowing through each power module when the most severe fault occurs. sm For the peak value, U N R is the rated voltage, and R is the value of the set energy-consuming resistor.

[0137] In one feasible implementation, the first setting module 1 includes:

[0138] The second setting unit is used to set the lower limit value of the number of power modules as the number of power modules;

[0139] The second setting module 2 includes:

[0140] The third setting unit is used to set the upper limit value of the energy-consuming resistor as the value of the energy-consuming resistor;

[0141] And / or, the third setting module 3 includes:

[0142] The fourth setting unit is used to set the lower limit value of the DC capacitor as the value of the DC capacitor.

[0143] The present invention also provides a main circuit parameter setting device for a distributed DC energy consumption device, comprising:

[0144] A memory is used to store instructions; wherein the instructions are used to implement the method for setting the main circuit parameters of the distributed DC energy consumption device as described in any of the above embodiments;

[0145] A processor for executing instructions in the memory.

[0146] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method for setting the main circuit parameters of a distributed DC energy consumption device as described in any of the above embodiments.

[0147] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the above-described device and module can be referred to the corresponding process in the foregoing method embodiments, and the specific beneficial effects of the above-described device and module can be referred to the corresponding beneficial effects in the foregoing method embodiments, and will not be repeated here.

[0148] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0149] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0150] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0151] If the integrated module is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0152] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for setting main circuit parameters of a distributed DC energy-consuming device, wherein the distributed DC energy-consuming device is composed of multiple cascaded power modules, each power module including a mechanical switch, a first diode, a second diode, a DC capacitor, a unidirectional power electronic switch, and an energy-consuming resistor, wherein one end of the mechanical switch, the cathode of the first diode, and the anode of the second diode are connected; the other end of the mechanical switch, the anode of the first diode, and one end of the energy-consuming resistor are connected to the cathode of the DC capacitor; the cathode of the second diode, the collector of the unidirectional power electronic switch, and the anode of the unidirectional power electronic switch are connected to the anode of the DC capacitor; and the emitter of the unidirectional power electronic switch is connected to the other end of the energy-consuming resistor, characterized in that... The method includes: The long-term average voltage of the power module is determined based on the voltage level of the switching devices of the power module. The rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device is obtained. The ratio of the rated voltage to the long-term average voltage is used as the lower limit of the number of power modules. The number of power modules is set according to the lower limit of the number of power modules. Determine the redundancy of the power modules, determine the total number of modules based on the set number of power modules and the redundancy, obtain the rated power and margin coefficient of the corresponding DC transmission system, calculate the upper limit value of the energy consumption resistor based on the rated voltage, the total number of modules, the rated power and the margin coefficient, and set the value of the energy consumption resistor based on the upper limit value of the energy consumption resistor; Determine the peak value of the voltage fluctuation peak of the power module capacitor. Calculate the average current value flowing through each power module when the most severe fault occurs based on the peak value, the rated voltage, and the set value of the energy-consuming resistor. Set the maximum period during which the power module can be put into and taken out of the system. Use the ratio of the product of the average current value and the maximum period to the peak value as the lower limit value of the DC capacitor. Set the value of the DC capacitor based on the lower limit value of the DC capacitor.

2. The method for setting the main circuit parameters of a distributed DC energy consumption device according to claim 1, characterized in that, Determining the redundancy of the power module includes: Set the redundancy rate of the power module; The redundancy of the power modules is calculated based on the redundancy rate and the number of power modules configured.

3. The method of claim 2, wherein, Setting the redundancy rate of the power module includes: The redundancy rate should be set to a value within 10%.

4. The method of claim 1, wherein, The process of obtaining the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device includes: When the corresponding DC transmission system adopts a symmetrical single-pole connection, the voltage between the corresponding poles is obtained as the rated voltage; when the corresponding DC transmission system adopts a symmetrical double-pole connection, the voltage between the corresponding pole and ground is obtained as the rated voltage; when the corresponding DC transmission system adopts a high-low valve group connection, the DC voltage of the corresponding single valve group is obtained as the rated voltage. And, obtaining the rated power of the corresponding DC transmission system includes: When the corresponding DC transmission system adopts a symmetrical single-pole connection, the power between the corresponding poles is obtained as the rated power; when the corresponding DC transmission system adopts a symmetrical double-pole connection, the power between the corresponding pole and ground is obtained as the rated power; when the corresponding DC transmission system adopts a high-low valve group connection, the power of the corresponding single valve group is obtained as the rated power.

5. The method of claim 1, wherein, The calculation of the upper limit value of the energy-consuming resistance based on the rated voltage, the total number of modules, the rated power, and the margin factor includes: The upper limit value of the energy-consuming resistor is calculated using the following formula: In the formula, R max U represents the upper limit of the energy-consuming resistor. N The rated voltage is N, k is the margin factor, and N is the zero-tolerance ratio. total P represents the total number of modules. N The rated power is [the power rating].

6. The method of claim 1, wherein, The calculation of the average current flowing through each power module when the most severe fault occurs, based on the peak value, the rated voltage, and the value of the set energy-consuming resistor, includes: The average current flowing through each power module during the most severe fault is calculated using the following formula: where I sm represents the average current value flowing through each power module at the time of the most severe fault, ΔU sm is the peak value, U N is the rated voltage, and R is the value of the energy dissipation resistor provided.

7. The method for setting the main circuit parameters of a distributed DC energy consumption device according to claim 1, characterized in that, Setting the number of power modules according to the lower limit value of the number of power modules includes: The number of power modules is defined as the lower limit of the number of power modules. Setting the value of the energy-consuming resistor according to the upper limit value of the energy-consuming resistor includes: The upper limit value of the energy-consuming resistor is taken as the value of the energy-consuming resistor; And / or, setting the value of the DC capacitor according to the lower limit value of the DC capacitor includes: The lower limit value of the DC capacitor is used as the value of the DC capacitor.

8. A main circuit parameter setting device for a distributed DC energy dissipation device, wherein the distributed DC energy dissipation device is composed of multiple cascaded power modules, each power module including a mechanical switch, a first diode, a second diode, a DC capacitor, a unidirectional power electronic switch, and an energy dissipation resistor, wherein one end of the mechanical switch, the negative terminal of the first diode, and the positive terminal of the second diode are connected; the other end of the mechanical switch, the positive terminal of the first diode, and one end of the energy dissipation resistor are connected to the negative terminal of the DC capacitor; the negative terminal of the second diode, the collector of the unidirectional power electronic switch, and the positive terminal of the DC capacitor are connected; and the emitter of the unidirectional power electronic switch and the other end of the energy dissipation resistor are connected, characterized in that... The device includes: The first setting module is used to determine the long-term average voltage of the power module according to the voltage level of the switching device of the power module, obtain the rated voltage of the DC transmission system corresponding to the distributed DC energy consumption device, use the ratio of the rated voltage to the long-term average voltage as the lower limit value of the number of power modules, and set the number of power modules according to the lower limit value of the number of power modules. The second setting module is used to determine the redundancy of the power modules, determine the total number of modules based on the set number of power modules and the redundancy, obtain the rated power and margin coefficient of the corresponding DC transmission system, calculate the upper limit value of the energy consumption resistor based on the rated voltage, the total number of modules, the rated power and the margin coefficient, and set the value of the energy consumption resistor based on the upper limit value of the energy consumption resistor. The third setting module is used to determine the peak value of the voltage fluctuation peak of the power module capacitor, calculate the average current value flowing through each power module when the most serious fault occurs based on the peak value, the rated voltage and the set energy-consuming resistor value, set the maximum period for the power module to be put into and taken out, use the ratio of the product of the average current value and the maximum period to the peak value as the lower limit value of the DC capacitor, and set the value of the DC capacitor based on the lower limit value of the DC capacitor.

9. A main circuit parameter setting device for a distributed DC energy consumption device, characterized in that, include: A memory for storing instructions; wherein the instructions are used to implement the method for setting the main circuit parameters of the distributed DC energy consumption device as described in any one of claims 1-7; A processor for executing instructions in the memory.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the method for setting the main circuit parameters of a distributed DC energy-consuming device as described in any one of claims 1-7.

Images