Loss and cost optimization design method for power electronic part of hybrid distribution network interconnection device

Abstract

The application provides a hybrid distribution network interconnection device power electronic part loss and cost optimization design method, which is based on a power electronic equipment topology structure, considers various losses of IGBT and anti-parallel diodes, determines dominant losses, considers an action process of the power electronic equipment, obtains various dominant losses based on a function generated by fitting an IGBT output characteristic curve, and obtains a function expression of the dominant losses based on electrical parameters and IGBT parameters; based on the power electronic equipment topology structure and a working mechanism, the number of various dominant losses in a normal working state is determined, and a loss model of the power electronic equipment is further constructed; electrical parameters of the power electronic equipment and the distribution network and IGBT parameters corresponding to various types are brought into the loss model of the power electronic equipment, energy of a single power frequency cycle loss is calculated through integration, and then average loss power of the power electronic equipment is obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical equipment, and particularly relates to a loss and cost optimization design method for a power electronic part of a hybrid distribution network interconnection device. BACKGROUND

[0002] Traditional distribution network flexible interconnection devices mainly include electromagnetic devices mainly with phase-shifting transformers and power electronic devices mainly with back-to-back converters. The electromagnetic devices have the advantage of low cost but low control accuracy, while the power electronic devices can improve the control accuracy but increase the cost and loss of the devices. In view of the contradiction between the two, some researchers have proposed an electromagnetic hybrid flexible interconnection device combining the two. Although the overall cost and loss can be reduced by optimizing the capacity of the electromagnetic part and the power electronic part, the capacity of the power electronic part cannot be infinitely reduced due to the need for fine adjustment, and therefore, the cost and loss optimization design of the power electronic part is of great significance to actual engineering. The main cost and loss of the power electronic part come from power semiconductor devices, and medium and high power converters usually use IGBT as switching devices, and therefore, comprehensive optimization and selection of IGBT are beneficial to the comprehensive optimization design of the loss and cost of the power electronic part of the electromagnetic hybrid device.

[0003] IGBT, as a high-performance power semiconductor device, plays a crucial role in the field of power electronics. With the advancement of technology, IGBTs provide high-speed switching operations while facing challenges in terms of loss and cost. Calculating the loss usually requires modeling the IGBT device, and current modeling of IGBT mainly focuses on physical models. Physical models are usually constructed using software simulation methods, which can provide accurate device transient voltage and current waveforms. However, they also have serious drawbacks: (1) a large number of difficult-to-obtain device manufacturing parameters, such as doping concentration and carrier lifetime, are required; (2) the simulation calculation is large, and in order to simulate the switching process, the simulation step is very short (usually less than 10 ns); (3) in transient simulation, the simulator needs to be iteratively solved, and the rapid voltage jump caused by device switching can easily cause non-convergence problems in iterative calculation. SUMMARY

[0004] The present application provides a loss and cost optimization design method for a power electronic part of a hybrid distribution network interconnection device, which provides an IGBT loss calculation method with simple characteristic parameter acquisition and strong operability, and comprehensively considers the loss and manufacturing cost to comprehensively optimize the device design scheme.

[0005] This solution includes IGBT output characteristic curve fitting, IGBT loss model construction, and comprehensive optimization design considering both loss and cost. Using equipment operating parameters, IGBT characteristic parameters, and IGBT market price as inputs, the solution calculates equipment loss and cost through a mathematical model of loss and cost. After normalizing the output loss and cost values, different or equal weights are assigned to them, resulting in a comprehensive score for design schemes using different IGBTs. The scheme with the lowest score is the optimal one. The loss calculation scheme provided by this invention requires parameters that can be obtained from manufacturer datasheets, making it highly operable. Furthermore, based on the calculated loss and cost, the weighting coefficients of both can be flexibly adjusted to meet different optimization design needs, thus adapting to various practical application scenarios.

[0006] The present invention specifically adopts the following technical solution:

[0007] A method for calculating power electronic losses in a hybrid distribution network interconnection device:

[0008] Based on the power electronic device topology, various losses of IGBTs and anti-parallel diodes are considered; and the dominant losses are determined.

[0009] Considering the operation process of power electronic equipment, based on the function generated by fitting the IGBT output characteristic curve, the functional expressions of various dominant losses based on electrical parameters and IGBT parameters are calculated.

[0010] Based on the topology and working mechanism of power electronic equipment, the quantity of various dominant losses under normal working conditions is determined, and a loss model of power electronic equipment is further constructed.

[0011] The electrical parameters of the power electronic equipment and the distribution network, as well as the corresponding IGBT parameters of various models, are input into the loss model of the power electronic equipment. The energy loss of a single power frequency cycle is calculated by integration, and then the average power loss of the power electronic equipment is obtained.

[0012] Furthermore, the various losses of the IGBT and the anti-parallel diode include: the IGBT's conduction loss, cutoff loss, turn-on loss, turn-off loss, and drive loss, and the anti-parallel diode's conduction loss, turn-on loss, reverse recovery loss, and cutoff loss; the dominant loss includes the IGBT's conduction loss P. Tcon Turn-on loss P Ton Turn-off loss P Toff And the on-state loss P of the anti-parallel diode. Dcon Reverse recovery loss P rr .

[0013] Furthermore, the electrical parameters of the power electronic equipment and distribution network include: active power, peak voltage, DC side voltage and current, power factor angle of the distribution network, grid angular frequency, and switching frequency.

[0014] Furthermore, the IGBT collector-emitter voltage U CE and current I C The typical curve is approximately fitted by the following function:

[0015]

[0016] The on-state loss of the IGBT is calculated as follows:

[0017]

[0018] The conduction loss of the anti-parallel diode is calculated as follows:

[0019]

[0020] Furthermore, the curve fitting is a linear fit based on the IGBT output characteristics.

[0021] A cost optimization design method for the power electronics section of a hybrid distribution network interconnection device: Based on the loss calculation method described above, the equipment loss is obtained. Then, the output loss value and cost value are normalized and assigned different or the same weights to obtain a comprehensive score for the design scheme using different IGBTs. The scheme with the lowest score is selected as the optimal scheme.

[0022] Furthermore, the calculation method for the overall score is as follows:

[0023]

[0024] In the formula X i P represents the overall score for each IGBT model, where α and β are the loss weight and cost weight, respectively. loss_i and P loss_max These are the losses and maximum losses of each IGBT model, M. i and M max These are the unit prices and maximum unit prices for each IGBT model.

[0025] Furthermore, a cost optimization design system for the power electronics component of a hybrid distribution network interconnection device, based on a computer system, is characterized by comprising: a loss calculation module, a cost acquisition module, and a comprehensive score calculation module;

[0026] The loss calculation module includes a loss model for power electronic equipment. The electrical parameters of the power electronic equipment and the distribution network, as well as the parameters of various types of IGBTs, are input into the loss model of the power electronic equipment. The energy lost in a single power frequency cycle is calculated by integration, thereby obtaining the average power loss of the power electronic equipment.

[0027] The cost acquisition module is used to input the unit price of various IGBT models;

[0028] The comprehensive score calculation module normalizes the loss value output by the loss calculation module and the cost value provided by the cost acquisition module, and assigns them different or the same weights to obtain the comprehensive score of the design scheme using different IGBTs.

[0029] Furthermore, the loss model of the power electronic device is obtained by: considering various losses of IGBTs and anti-parallel diodes based on the topology of the power electronic device; and determining the dominant loss.

[0030] Considering the operation process of power electronic equipment, based on the function generated by fitting the IGBT output characteristic curve, the functional expressions of various dominant losses based on electrical parameters and IGBT parameters are calculated.

[0031] Based on the topology and working mechanism of power electronic equipment, the quantity of various dominant losses under normal working conditions is determined, and further constructed to obtain the results.

[0032] Furthermore, the calculation method for the comprehensive score is as follows:

[0033]

[0034] In the formula X i P represents the overall score for each IGBT model, where α and β are the loss weight and cost weight, respectively. loss_i and P loss_max These are the losses and maximum losses of each IGBT model, M. i and M max These are the unit prices and maximum unit prices for each IGBT model.

[0035] Compared to existing technologies, the computational model provided by this invention and its preferred solutions is simple, easy to calculate and apply, and the parameters required for calculating the switching device losses are derived from the manufacturer's datasheet, making it more operable. In a further solution, the cost of IGBTs is also considered, comprehensively optimizing the equipment losses and costs of the electromagnetic hybrid device, making it more suitable for practical engineering applications. Attached Figure Description

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0037] Figure 1 This is a schematic diagram of the power electronic device topology in an embodiment of the present invention;

[0038] Figure 2 The selected IGBT collector-emitter voltage U in this embodiment of the invention CE and current I C Line graph;

[0039] Figure 3 The waveforms shown are typical IGBT switching waveforms in embodiments of the present invention.

[0040] Figure 4 This is a graph showing the loss and cost scores when the loss weight is 1 and the cost weight is 0 in an embodiment of the present invention.

[0041] Figure 5 This is a graph showing the loss and cost scores when the loss weight is 0 and the cost weight is 1 in an embodiment of the present invention.

[0042] Figure 6 This is a graph showing the loss and cost scores when the loss weight is 0.5 and the cost weight is 0.5 in an embodiment of the present invention.

[0043] Figure 7 This is a graph showing the loss and cost scores in an embodiment of the present invention with a loss weight of 0.8 and a cost weight of 0.2.

[0044] Figure 8 This is a graph showing the loss and cost scores when the loss weight is 0.2 and the cost weight is 0.8 in an embodiment of the present invention.

[0045] Figure 9 This is a schematic diagram of the system model in an embodiment of the present invention. Detailed Implementation

[0046] In the following, specific embodiments of this application will be described in detail with reference to the accompanying drawings. Based on these detailed descriptions, those skilled in the art will be able to clearly understand and implement this application. Without departing from the principles of this application, features from various embodiments can be combined to obtain new implementations, or certain features from some embodiments can be substituted to obtain other preferred implementations.

[0047] To make the features and advantages of this patent more apparent and understandable, specific embodiments are provided below, along with accompanying drawings, for detailed explanation:

[0048] like Figure 9As shown, the overall design scheme provided by this invention includes IGBT output characteristic curve fitting, IGBT loss model construction, and comprehensive optimization design of loss and cost. Using equipment operating parameters, IGBT characteristic parameters, and IGBT market price as inputs, the equipment loss and cost are calculated through a loss and cost mathematical model. After normalizing the output loss and cost values, different or equal weights are assigned to them, resulting in a comprehensive score for design schemes using different IGBTs. The scheme with the lowest score is the optimal one.

[0049] The design of the present invention will be further described below through a specific example:

[0050] The power electronic equipment topology in this embodiment is as follows: Figure 1 As shown, it includes a front-end three-phase rectifier and a back-end three-phase inverter. The loss calculation model will be constructed in detail below.

[0051] The losses of an IGBT include its own conduction loss, cutoff loss, turn-on loss, turn-off loss, and drive loss, as well as the conduction loss, turn-on loss, reverse recovery loss, and cutoff loss of the anti-parallel diode. The dominant loss among these is the IGBT's conduction loss P. Tcon Turn-on loss P Ton Turn-off loss P Toff And the on-state loss P of the anti-parallel diode. Dcon Reverse recovery loss P rr The remaining losses are much smaller than the losses mentioned above and can be ignored.

[0052] IGBT collector-emitter voltage U CE and current I C Typical curves such as Figure 2 As shown, the curve can be approximately fitted to the following function:

[0053]

[0054] Based on the above formula, the on-state loss of the IGBT can be calculated as follows:

[0055]

[0056] Similarly, the conduction loss of the anti-parallel diode can be calculated as follows:

[0057]

[0058] A typical switching waveform of an IGBT is as follows: Figure 3 As shown, the overshoot of the turn-on current is mainly related to the reverse recovery current of the diode. In the interval 1-2, the current rises approximately linearly, and the rise time t... r The switching frequency is defined as f, which can be found in the chip datasheet.s The DC side voltage of the rectifier is U DC At this point, the collector current of the IGBT can be approximately expressed as:

[0059]

[0060] The turn-on loss of the IGBT in this range can be expressed as:

[0061]

[0062] In the 2-3 interval, the anti-parallel diode begins reverse recovery. At this time, the voltage drop of the anti-parallel diode is very small, and its conduction loss can be ignored. The collector current of the IGBT at this point can be approximated as:

[0063]

[0064] The turn-on loss of the IGBT in this range can be expressed as:

[0065]

[0066] In the 3-4 interval, the anti-parallel diode withstands reverse voltage, and the reverse recovery current gradually decreases to 0. Meanwhile, the collector-emitter voltage of the IGBT also decreases to the on-state voltage. At this time, the collector-emitter voltage and current of the IGBT, and the voltage and current of the anti-parallel diode, can be approximated as follows:

[0067]

[0068] The turn-on loss of the IGBT in the 3-4 interval can be expressed as:

[0069]

[0070] In summary, the IGBT turn-on loss during the entire turn-on process can be calculated as follows:

[0071]

[0072] Furthermore, the reverse recovery loss of the anti-parallel diode is expressed as follows:

[0073]

[0074] against Figure 3 The turn-off process shown can be divided into a collector-emitter voltage rise phase and a collector current fall phase. The time of the collector-emitter voltage rise phase is t. roff The collector current decreases over time t. f Then, the collector-emitter voltage during the rising phase and the collector current during the falling phase can be expressed as:

[0075]

[0076] The turn-off loss of the IGBT can then be expressed as:

[0077]

[0078] Let the active power be P. Since the rectifier is only responsible for stabilizing the DC bus voltage, it can be approximated as operating with unity power factor. Then, the input phase voltage and current of the three-phase rectifier can be expressed as:

[0079]

[0080] From the topology of the three-phase rectifier, it can be seen that at any given time, one IGBT in the same bridge arm is zero-voltage turn-on and zero-current turn-off, and the current flows through the anti-parallel diode of the IGBT during the conduction process; while the other IGBT is hard turn-on and hard turn-off, and the current flows from the collector to the emitter of the IGBT during the conduction process, and its anti-parallel diode does not have a reverse recovery process. Therefore, the two IGBTs in the same bridge arm only have one turn-on loss, one turn-off loss, one reverse recovery loss, one IGBT conduction loss, and one anti-parallel diode conduction loss. The three-phase rectifier consists of three bridge arms, so its total loss is 3 turn-on losses, 3 turn-off losses, 3 reverse recovery losses, 3 IGBT conduction losses, and 3 anti-parallel diode conduction losses. Substituting equation (14) into (2), (3), (10), (11), and (13) respectively, the loss of the three-phase rectifier can be expressed as:

[0081]

[0082] The output of the three-phase inverter is connected in series with the distribution network via a transformer for compensation. Therefore, reactive power from the distribution network is transferred to the three-phase inverter. The power factor angle of the distribution network is defined as follows: The output phase voltage and current of a three-phase inverter can then be expressed as:

[0083]

[0084] Similar to a three-phase rectifier, a three-phase inverter also consists of three bridge arms. Therefore, its total losses are 3 turn-on losses, 3 turn-off losses, 3 reverse recovery losses, 3 IGBT on-state losses, and 3 anti-parallel diode on-state losses. Substituting equation (16) into equations (2), (3), (10), (11), and (13) respectively, the losses of the three-phase inverter can be expressed as:

[0085]

[0086] In the above embodiment, the active power P of the electromagnetic mixing device is 30kW and the peak voltage V of the rectifier is... r311V, inverter peak voltage V inv The DC side voltage of the rectifier is 290V. DC The voltage is 800V, the DC side current of the rectifier is 37.5A, and the power factor angle of the distribution network is... The parameters are π / 6, the grid angular frequency ω0 is 100π, and the switching frequency is 5kHz. Different IGBT parameters are substituted into the loss models of the rectifier and inverter described above. The energy loss per power frequency cycle is calculated by integration, thus obtaining the average power loss of the rectifier and inverter. In this embodiment, 40 types of IGBTs are selected for loss calculation, and the results are shown in Table 1.

[0087] Table 1 Power loss and efficiency of power electronics components for different IGBT models

[0088]

[0089] Table 1 (Continued) shows the power loss and efficiency of the power electronics components for different IGBT models.

[0090]

[0091] The cost difference is mainly reflected in the selling price of IGBTs. Therefore, a cost model can be obtained by surveying the selling prices of different IGBT models. As shown in equation (18), by assigning the same or different weights to the obtained loss and cost calculation results, a comprehensive optimization design with various tendencies can be obtained. In the equation, X i P represents the overall score for each IGBT model, where α and β are the loss weight and cost weight, respectively. loss_i and P loss_max These represent the losses of various IGBT models and the maximum losses among 40 IGBT types, M. i and M max The unit prices of each IGBT model and the maximum unit price among the 40 IGBT models are respectively. Substituting the relevant data into equation (18), the calculation results are shown in Table 2.

[0092]

[0093] Table 2. Results of Comprehensive Optimization Design

[0094]

[0095] The calculation results are obtained by assigning different or the same weights to the loss and cost values, respectively. Figure 4 to Figure 8 As shown, the IGBT sequence sorting method is the same as the IGBT model sorting in Table 1.

[0096] In the embodiment, when the loss weight is 1 and the cost weight is 0, IGBTs are selected, such as... Figure 4As shown, the IKY120N120CH7 has a power loss of 1113.851W, a transmission efficiency of 96.28%, and a unit price of 70.48 yuan.

[0097] When the loss weight is 0 and the cost weight is 1, IGBTs are selected. Figure 5 As shown, the CRG40T120AK3S has a power loss of 1372.598W, a transmission efficiency of 95.42%, and a unit price of 13.22 yuan.

[0098] If the weights for loss and cost are each 0.5, the preferred IGBT model is as follows: Figure 6 As shown, the CRG40T120AK3S has a power loss of 1372.598W, a transmission efficiency of 95.42%, and a unit price of 13.22 yuan.

[0099] If the loss weight is 0.8 and the cost weight is 0.2, the preferred IGBT model is as follows: Figure 7 As shown, the model is IKW50N120CS7, with a power loss of 1166.878W, a transmission efficiency of 96.11%, and a unit price of 38.52 yuan.

[0100] If the loss weight is 0.2 and the cost weight is 0.8, the preferred IGBT model is as follows: Figure 8 As shown, the CRG40T120AK3S has a power loss of 1372.598W, a transmission efficiency of 95.42%, and a unit price of 13.22 yuan.

[0101] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0102] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure One One or more processes and / or boxes Figure One A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure One One or more processes and / or boxes Figure One The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure One One or more processes and / or boxes Figure One The steps of the function specified in one or more boxes.

[0105] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0106] The above description is a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

[0107] This patent is not limited to the above-described preferred embodiments. Anyone can derive other various forms of hybrid power distribution network interconnection device power electronic component loss and cost optimization design methods based on the inspiration of this patent. All equivalent changes and modifications made within the scope of the patent application of this invention shall fall within the scope of this patent.

Claims

1. A method for calculating the loss of a power electronic part of a hybrid distribution network interconnection device, characterized in that: based on the topology of the power electronic device, considering various losses of IGBT and anti-parallel diode; and determining the dominant loss; considering the action process of the power electronic device, based on the function generated by fitting the IGBT output characteristic curve, calculating the various dominant losses based on the function expression of the electrical parameters and the IGBT parameters; based on the topology and working mechanism of the power electronic device, determining the number of various dominant losses in the normal working state, and further constructing the loss model of the power electronic device; the electrical parameters of the power electronic device and the distribution network and the corresponding IGBT parameters of each type are brought into the loss model of the power electronic device, the energy of the single power frequency cycle loss is calculated by integration, and then the average loss power of the power electronic device is obtained; The various losses of the IGBT and the anti-parallel diode include: the on-state loss, the off-state loss, the turn-on loss, the turn-off loss and the driving loss of the IGBT, and the on-state loss, the turn-on loss, the reverse recovery loss and the off-state loss of the anti-parallel diode; the dominant losses include the on-state loss P Tcon , the turn-on loss P Ton , the turn-off loss P Toff of the IGBT, and the on-state loss P Dcon , the reverse recovery loss P rr of the anti-parallel diode; IGBT collector voltage U CE and current I C Typical curves are approximately fitted to the following functions: the on-state loss of the IGBT is calculated as follows: the on-state loss of the anti-parallel diode is calculated as follows: the device loss is calculated, and after the output loss value and the cost value are normalized, different or the same weights are assigned to obtain the comprehensive score of the design scheme using different IGBTs, and the lowest score is taken as the optimal scheme; the calculation method of the comprehensive score is as follows: In the formula, X i is the comprehensive score of each type of IGBT, and α and β are the loss weight and cost weight, respectively, P loss_i and P loss_max are the loss of each type of IGBT and the maximum loss, respectively, M i and M max are the unit price of each type of IGBT and the maximum unit price, respectively.

2. The method of claim 1, wherein: The electrical parameters of the power electronic device and the distribution network include active power, voltage peak value, DC side voltage and current, distribution network power factor angle, grid angular frequency, and switching frequency.

3. The method of claim 1, wherein: The curve fitting is a linear fitting based on the IGBT output characteristics.

4. A system for cost-optimized design of a power electronics section of a hybrid distribution-grid interconnection device, based on a computer system, characterized in that It includes: a loss calculation module, a cost acquisition module, and a comprehensive score calculation module; and the loss calculation module realizes loss calculation based on any one of claims 1-3; the loss calculation module includes a loss model of the power electronic device, the electrical parameters of the power electronic device and the distribution network and the corresponding IGBT parameters of each type are brought into the loss model of the power electronic device, the energy of the single power frequency cycle loss is calculated by integration, and then the average loss power of the power electronic device is obtained; the cost acquisition module is used to input the unit price of various types of IGBTs; the comprehensive score calculation module assigns different or the same weights to the loss value output by the loss calculation module and the cost value provided by the cost acquisition module after normalization, and obtains the comprehensive score of the design scheme using different IGBTs. 5.The cost optimization design system of the power electronic part of the hybrid distribution network interconnection device according to claim 4, characterized in that: the loss model of the power electronic device is obtained in the following way: based on the topology of the power electronic device, considering various losses of IGBT and anti-parallel diode; and determining the dominant loss; considering the action process of the power electronic device, based on the function generated by fitting the IGBT output characteristic curve, calculating the various dominant losses based on the function expression of the electrical parameters and the IGBT parameters; based on the topology and working mechanism of the power electronic device, determining the number of various dominant losses in the normal working state, and further constructing the loss model of the power electronic device.

6. The system for cost optimization design of hybrid distribution internet-of-things device power electronics part according to claim 4, wherein: The calculation method of the comprehensive score is as follows: where X i is the comprehensive score of each type of IGBT, and α and β are the loss weight and cost weight, respectively, P loss_i and P loss_max are the loss of each type of IGBT and the maximum loss, respectively, M i and M max are the unit price of each type of IGBT and the maximum unit price, respectively.

Images