A general reconfigurable simulation system for power electronic converters

Abstract

The application discloses a general reconfigurable simulation system of a power electronic converter, comprising: a dynamic element module, which is used for solving a dynamic element state equation according to a forward Euler method to obtain a dynamic element state variable, and sending the dynamic element state variable to a switch module according to a preset selection instruction; the switch module is used for constructing a general matrix model for a bridge arm switch of the converter, processing the dynamic element state variable through the general matrix model, and generating a switch voltage and a switch state instruction; a neutral point voltage solving module, which is used for constructing a neutral point voltage model for a three-phase rectification or inversion circuit according to the switch voltage and the switch state instruction, and solving to obtain a neutral point voltage; and a power supply module, which is used for providing different power supply voltages for the neutral point voltage solving module, wherein the power supply voltages include three-phase alternating voltages and a direct current voltage. The technical problems that the simulation adjustment flexibility is poor in different scenes, the modeling is complicated due to the increase of system element complexity, and the simulation compilation is time-consuming in the prior art are solved.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to a general reconfigurable simulation system for power electronic converters. Background Technology

[0002] The proportion of non-renewable energy generation, such as thermal power, will gradually decrease. Future power systems will rely primarily on wind and solar power, which will be transmitted through power electronic devices such as three-phase converters. In building a new power system dominated by new energy sources, the trend towards power electronics in the power system is irreversible, and three-phase converters will be widely used in future power systems. Real-time simulation technology has a wide range of applications. From the perspective of the energy and power sector alone, real-time simulation of three-phase converters is an effective tool for studying and understanding the characteristics of renewable energy and power electronic equipment, as well as for power system analysis and fault prevention. This technology can effectively simulate the real-time dynamics and interactions of systems or processes, and can test and evaluate the performance of systems under real-world conditions without the need to build physical prototypes.

[0003] Existing real-time simulation modeling methods are typically designed for different power electronic devices and topologies. When the type of power electronic device or topology changes, the design is redesigned according to the new topology or operating parameters. Then, the mathematical model is rewritten and compiled into a hardware language, and finally, real-time simulation is performed on an FPGA.

[0004] However, existing technologies are typically designed for specific power electronic topologies and operating conditions, resulting in a lack of model flexibility. Once the power system's topology or operating parameters change, the model may need to be redesigned, limiting its applicability across different system configurations and conditions. Furthermore, as the complexity of power electronic systems increases, traditional modeling methods often involve numerous manual calculations and steps, making the modeling process cumbersome and error-prone. This not only increases the time cost of model building but also places higher technical demands on designers. Simulating mathematical models on FPGAs usually requires compilation before execution. For complex systems or large-scale power electronic topologies, this compilation process can be very time-consuming, leading to extended waiting times for simulation results after topology changes when performing simulations on different topologies. Summary of the Invention

[0005] This application provides a general reconfigurable simulation system for power electronic converters, which solves the technical problems of poor flexibility in simulation adjustment for different scenarios, cumbersome modeling due to increased complexity of system components, and time-consuming compilation for multiple simulations in the existing technology.

[0006] In view of this, this application provides a general reconfigurable simulation system for power electronic converters, including: a dynamic element module, a switching module, a neutral point voltage solving module, and a power supply module;

[0007] The dynamic element module is used to solve the dynamic element state equation according to the forward Euler method to obtain the dynamic element state quantity, and send the dynamic element state quantity to the switch module according to the preset selection instruction. The dynamic element state quantity includes inductor current and capacitor voltage.

[0008] The switching module is used to construct a general matrix model for the bridge arm switches of the converter, process the dynamic element state variables through the general matrix model, and generate switching voltage and switching state commands. The switching modes of the general matrix model include full control mode, no control mode, thyristor semi-control mode and switch reverse parallel mode.

[0009] The neutral point voltage solving module is used to construct a neutral point voltage model for a three-phase rectifier or inverter circuit based on the switching voltage and the switching state command, and solve for the neutral point voltage.

[0010] The power supply module is used to provide different power supply voltages for the neutral point voltage solving module. The power supply voltage includes three-phase AC voltage and DC voltage, and the amplitude, step size, frequency and initial value of the power supply voltage can be adjusted.

[0011] Preferably, the switch module is specifically used for:

[0012] Construct a general matrix model for the bridge arm switches of the converter;

[0013] The switching mode of the general matrix model is determined based on the control signal, and the dynamic element state variables are analyzed through the general matrix model to generate switching voltage and switching state commands.

[0014] The switching modes include full control mode, no control mode, thyristor semi-control mode, and switch reverse parallel mode.

[0015] Preferably, the neutral point voltage solving module is specifically used for:

[0016] Based on the switching voltage and the switching state command, construct a neutral point voltage model for a three-phase rectifier or inverter circuit;

[0017] With three phases on, the neutral point voltage model is solved to obtain the full conduction voltage;

[0018] In the case of three-phase non-fully conducting, a two-phase switch conduction model is constructed and the neutral point voltage model is solved to obtain the non-fully conducting voltage.

[0019] The fully on voltage and the non-fully on voltage constitute the neutral point voltage.

[0020] Preferably, the power module is further used for:

[0021] Select initial values ​​for the three-phase AC voltage;

[0022] Select the three-phase amplitude and DC voltage amplitude for the power supply voltage.

[0023] Preferably, it further includes: a connection relationship module;

[0024] The connection module is used to connect the dynamic element module, the switch module, the neutral point voltage calculation module, and the power supply module to realize closed-loop communication and electrical quantity interaction, and generate a connection mathematical model.

[0025] Preferably, the dynamic element module includes 12 dynamic elements;

[0026] The switching module includes 12 selectable switches, which include diode switches, fully controlled switches, and semi-controlled thyristor switches.

[0027] The power module includes a three-phase AC power supply, two DC power supplies, and a gain module.

[0028] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0029] This application provides a general reconfigurable simulation system for power electronic converters, comprising: a dynamic element module, a switching module, a neutral point voltage solving module, a power supply module, and a connection relationship module; the dynamic element module is used to solve the state equations of dynamic elements according to the forward Euler method to obtain the state quantities of dynamic elements, and send the state quantities of dynamic elements to the switching module according to preset selection instructions. The state quantities of dynamic elements include inductor current and capacitor voltage; the switching module is used to construct a general matrix model for the bridge arm switches of the converter, process the state quantities of dynamic elements through the general matrix model, and generate switching voltage and switching state instructions. The switching modes of the general matrix model include fully controlled mode, uncontrolled mode, thyristor semi-controlled mode, and switch reverse parallel mode; the neutral point voltage solving module is used to construct a neutral point voltage model for a three-phase rectifier or inverter circuit according to the switching voltage and switching state instructions, and solve for the neutral point voltage; the power supply module is used to provide different power supply voltages for the neutral point voltage solving module. The power supply voltages include three-phase AC voltage and DC voltage, and the amplitude, step size, frequency, and initial value of the power supply voltage are all adjustable.

[0030] This application provides a general reconfigurable simulation system for power electronic converters, which adapts to the modeling needs of various scenarios and types of components based on multiple general modules. When different converter topologies need to be changed for simulation, the simulated converter topology can be altered by changing the signals triggering different modules, adjusting state variables, and changing switch combination states. This process can be applied to converter simulations of complex power electronic systems in different scenarios. Furthermore, since topology transformation only involves parameter adjustment and does not require recompilation and reprogramming, it avoids the time-consuming and laborious problems caused by multiple simulation compilations. Therefore, this application can solve the technical problems of poor flexibility in simulation adjustments for different scenarios, cumbersome modeling due to increased system component complexity, and time-consuming multiple simulation compilations in existing technologies. Attached Figure Description

[0031] Figure 1 A schematic diagram of the structure of a general reconfigurable simulation system for power electronic converters provided in this application embodiment;

[0032] Figure 2 A schematic diagram of the basic circuit model of the switch provided in the embodiments of this application;

[0033] Figure 3 A schematic diagram of the fully controlled switch circuit model provided in the embodiments of this application.

[0034] Figure 4 A schematic diagram of an uncontrolled switching circuit model provided in an embodiment of this application.

[0035] Figure 5 A schematic diagram of a semi-controlled switching circuit model provided in the embodiments of this application.

[0036] Figure 6 A schematic diagram of a fully controlled switch and a freewheeling diode in reverse parallel switching circuit provided in an embodiment of this application. Detailed Implementation

[0037] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0038] For easier understanding, please refer to Figure 1 This application provides an embodiment of a general reconfigurable simulation system for power electronic converters, comprising: a dynamic element module, a switching module, a neutral point voltage solving module, and a power supply module.

[0039] The dynamic element module is used to solve the state equation of the dynamic element according to the forward Euler method to obtain the dynamic element state quantity. According to the preset selection command, the dynamic element state quantity is sent to the switching module. The dynamic element state quantity includes inductor current and capacitor voltage.

[0040] Furthermore, the dynamic element module of this embodiment includes 12 dynamic elements.

[0041] It should be noted that the dynamic elements in the dynamic element module of this embodiment mainly refer to inductors and capacitors. The state equations of the dynamic elements can be solved using the forward Euler method, and are expressed as follows:

[0042]

[0043] Where H1 is a matrix, which in this embodiment can be a 12×12 matrix, b1 is a row and column vector, and x n It is the dynamic component state quantity from the previous moment. This represents the state of the dynamic component at the current moment, which can be expressed as inductor current or capacitor voltage depending on the actual simulation requirements.

[0044] The dynamic element module includes a selection function. For each input state variable, there is a 13-branch conditional structure. Input 0 corresponds to the first branch, and the output is a column vector with 12 rows of 0s. Input 1 corresponds to the second branch, and the output of the second branch is the state variable input added to the first row. The remaining rows from the second to the twelfth row are inputs of 0s, and so on, for a total of 13 branches. The outputs of the conditional structures are accumulated after processing the state variables, thus achieving the effect that input 1 outputs to the first row, input 2 outputs to the second row. The output state variables can be adjusted according to simulation requirements, and then the switching module is affected by the state variables; the specifics are not elaborated here.

[0045] The switching module is used to build a general matrix model for the bridge arm switches of the converter. The general matrix model processes the dynamic component state variables and generates switching voltage and switching state commands. The switching modes of the general matrix model include fully controlled mode, uncontrolled mode, thyristor semi-controlled mode and switch reverse parallel mode.

[0046] Furthermore, the switch module is specifically used for:

[0047] Construct a general matrix model for the bridge arm switches of the converter;

[0048] The switching mode of the general matrix model is determined based on the control signal, and the state variables of dynamic components are analyzed through the general matrix model to generate switching voltage and switching state commands.

[0049] The switching modes include fully controlled mode, uncontrolled mode, thyristor semi-controlled mode, and switch reverse parallel mode.

[0050] Furthermore, the switching module of this embodiment includes 12 selectable switches, which include diode switches, fully controlled switches, and semi-controlled thyristor switches.

[0051] It should be noted that the switching module includes multiple modules. This embodiment analyzes the switching state using two switches as a pair. Each switch has four modes: fully controlled mode, uncontrolled mode, thyristor semi-controlled mode, and reverse parallel mode. The reverse parallel mode refers to the case where the fully controlled switch and the freewheeling diode are connected in reverse parallel. For the switching circuit diagram and parameters described by the general matrix model, please refer to... Figure 2 For each pair of bridge arms in the converter, the model is as follows: i a (Phase A current), V + (Voltage of positive terminal to ground), V - (Voltage to ground) is the input quantity, i1 (positive line current), i2 (positive line current), V a (Switch output voltage) is the output quantity, which can be expressed in a general matrix model as follows:

[0052]

[0053] in, These are the currents flowing through the positive and negative poles, respectively, and their values ​​are equal to i1 and i2.

[0054] That is to say:

[0055]

[0056] in, For the aforementioned 12 rows and columns of state variables, b2 consists of four groups of i a V + V - The resulting 12-row, 12-column vector, H2, is composed of four identical 3×3 matrices as shown on the leftmost side of the above equation.

[0057] In a three-phase converter, the three phases ABC include switches S1, S2, S3, S4, S5, and S6, and the voltage values ​​output by the three pairs of switches, i.e., the switch voltage V. a V b V c This will be input into the neutral point voltage calculation module. b2 is expressed as:

[0058]

[0059] The topology mode of the switches in the switching module needs to be determined based on specific criteria. For details, please refer to [link to full control mode]. Figure 3Assuming the control signal is represented by g, i is the switching current (positive direction is the direction directly opposite the switch), and S is the switch, where S = 1 indicates the switch is on and S = 0 indicates the switch is off; the switching on and off is entirely determined by the control signal, and the specific mathematical model is as follows:

[0060]

[0061]

[0062] For uncontrolled mode, please refer to Figure 4 The opening and closing of the switch are related to the direction of the current. When the current is positive, the upper bridge arm conducts; when the current is negative, the lower bridge arm conducts. The specific mathematical model is expressed as follows:

[0063]

[0064] For thyristor semi-controlled mode, please refer to Figure 5 The switching on and off of the switch is related to both the current direction and the control signal. If the switch was in the on state in the previous moment, and the current is positive, the switch is on; if the current is reversed, the switch is off. If the switch was in the off state in the previous moment, and a trigger signal is present and the current is positive, the switch is on; if there is no trigger signal or the current is reversed, the switch remains off. The specific mathematical model is expressed as follows:

[0065]

[0066] in, These represent the switching states of switches S1 and S2 at the previous moment, respectively.

[0067] For the reverse parallel mode of the switches, please refer to Figure 6 The control signal g can control the switching on and off of the switch. When there is no control signal, the switching current can also flow through the freewheeling diode; in this case, if the current is forward, the upper bridge arm conducts; if the current is reverse, the lower bridge arm conducts. The specific mathematical model is expressed as follows:

[0068]

[0069] The neutral point voltage solving module is used to construct a neutral point voltage model for a three-phase rectifier or inverter circuit based on the switching voltage and switching state commands, and solve for the neutral point voltage.

[0070] Furthermore, the neutral point voltage solving module is specifically used for:

[0071] Construct a neutral point voltage model for a three-phase rectifier or inverter circuit based on the switching voltage and switching status commands;

[0072] With three phases on, the neutral point voltage model is solved to obtain the full conduction voltage;

[0073] In the case of three-phase non-fully conducting, a two-phase switch conduction model is constructed and the neutral point voltage model is solved to obtain the non-fully conducting voltage.

[0074] The fully conducting voltage and the non-fully conducting voltage constitute the neutral point voltage.

[0075] It should be noted that, assuming the neutral point is N and the grounding point is G, for a non-semi-controlled switch, i.e., when all three phases are conducting, the mathematical model for solving the neutral point voltage is expressed as follows:

[0076]

[0077] Among them, e a e b e c The amplitude of the three-phase voltage source input to the power module, at which time V NG This is the fully on voltage.

[0078] For topologies with semi-controlled switches, two phases may be conducting or not conducting. In this case, the neutral point voltage calculation is also related to the switch conduction and off-state conditions. We can analyze a model where two phases are conducting or not conducting, i.e., a two-phase conducting model. Let k represent the total number of switch pairs conducting.

[0079] k = S1 + S2 + S3 + S4 + S5 + S6

[0080] 'a' indicates whether phase A is conducting: a = S1 + S2;

[0081] b indicates whether phase A is conducting: b = S3 + S4;

[0082] c indicates whether phase A is conducting: c = S5 + S6;

[0083] The neutral point voltage can then be calculated as follows:

[0084]

[0085] At this time V NG This is a non-conducting voltage. Here, if k≤1, meaning either single-phase conduction or no conduction, and single-phase conduction alone cannot form a circuit, then V... NG =0. The voltage at full conduction and the voltage at non-full conduction are the neutral point voltages.

[0086] The power supply module provides different power supply voltages for the neutral point voltage calculation module. The power supply voltages include three-phase AC voltage and DC voltage. The amplitude, step size, frequency and initial value of the power supply voltage can all be adjusted.

[0087] Furthermore, the power module is also used for:

[0088] Select initial values ​​for the three-phase AC voltage;

[0089] Select the three-phase amplitude and DC voltage amplitude for the power supply voltage.

[0090] Furthermore, the power supply module of this embodiment includes a three-phase AC power supply, two DC power supplies, and a gain module.

[0091] It should be noted that the gain module allows for free adjustment of the amplitude, and the AC power module also allows setting the step size, frequency, and initial value. Through a selection mechanism, parameters are input to the dynamic component module according to the actual simulation requirements. Combined with the influence of the connection module, when using three-phase AC power, the three-phase power supply values ​​are also directly input to the neutral point voltage calculation module. Three-phase rectifier-inverter topologies all require solving for the neutral point voltage.

[0092] The initial values ​​for the three-phase AC power supply of the power module can be selected, i.e., the three-phase initial values:

[0093]

[0094] Selection of three-phase amplitude and DC voltage amplitude:

[0095]

[0096] The power supply module inputs the power supply values ​​required for simulation into the neutral point voltage solution module and the connection relationship module.

[0097] Furthermore, it also includes: a connection relationship module;

[0098] The connection module is used to connect the dynamic element module, the switch module, the neutral point voltage solver module, and the power supply module to achieve closed-loop communication and electrical quantity interaction, and generate a connection mathematical model.

[0099] It should be noted that the connection module connects the preceding dynamic element module, switching module, power supply module, and neutral point voltage calculation module, and inputs the calculated output quantities into the dynamic element and switching module to form a closed loop. Its mathematical model is as follows:

[0100] x4n+1=H4*b+a4

[0101] H4 is also a 12×12 matrix. b4, the input to this module, is obtained by combining the outputs from the preceding dynamic element module, switch module, neutral point voltage solver module, and power supply module through a selection module. a4 is input from the power supply module through the selection module. The final result is... After passing through the selection module, the data is input to the dynamic element module b1 and the switch module b2, such as... Figure 1 b1_4 and b2_4.

[0102] It should be noted that the neutral point voltage calculated by the neutral point voltage calculation module in this embodiment is sent to the connection relationship module. The connection relationship module is used to realize the communication and electrical connections between various modules in the system, ensuring the interaction and data transmission of electrical quantities. For details, please refer to [link to relevant documentation]. Figure 1 The connection relationship is shown.

[0103] The calculations for the dynamic component module, the sinusoidal AC power supply for the power module, and various control signals all require initial values. To save the time required for each interactive re-execution during online compilation, the initial call is changed to a user-defined reset call. This allows for switching topologies during online execution without stopping the process; simply changing different parameters and initial values ​​during execution is sufficient to switch topologies directly.

[0104] Combination Figure 1 It can be seen that the output parameters of the dynamic element module are input to the switch module and the connection relationship module; the switch voltage and switch status command in the output parameters of the switch module are input to the neutral point voltage calculation module and the connection relationship module, and the switch status command also acts on the dynamic element module; the neutral point voltage calculated by the neutral point voltage calculation module is directly input to the connection relationship module; the connection relationship module receives information from all modules and then feeds it back to the dynamic element module and the switch module; the power supply module mainly provides the input power signal to the neutral point voltage calculation module.

[0105] This application provides a general reconfigurable simulation system for power electronic converters, which adapts to the modeling needs of various scenarios and types of components based on multiple general modules. When different converter topologies need to be changed for simulation, the simulated converter topology can be altered by changing the signals triggering different modules, adjusting state variables, and changing switch combination states. This process can be applied to converter simulations of complex power electronic systems in different scenarios. Furthermore, since topology transformation only involves parameter adjustment and does not require recompilation and reprogramming, it avoids the time-consuming and laborious problems caused by multiple simulation compilations. Therefore, this application can solve the technical problems of poor flexibility in simulation adjustments for different scenarios, cumbersome modeling due to increased system component complexity, and time-consuming multiple simulation compilations in existing technologies.

[0106] 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 units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0107] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0108] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0109] If the integrated unit is implemented as a software functional unit 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 this application, 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 for executing all or part of the steps of the methods described in the various embodiments of this application through a computer device (which may be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0110] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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 this application.

Claims

1. A general-purpose reconfigurable simulation system for power electronic converters, characterized in that, include: Dynamic element module, switch module, neutral point voltage solver module, and power supply module; The dynamic element module is used to solve the dynamic element state equation according to the forward Euler method to obtain the dynamic element state quantity, and send the dynamic element state quantity to the switch module according to the preset selection instruction. The dynamic element state quantity includes inductor current and capacitor voltage. The switching module is used to construct a general matrix model for the bridge arm switches of the converter, process the dynamic element state variables through the general matrix model, and generate switching voltage and switching state commands. The switching modes of the general matrix model include fully controlled mode, uncontrolled mode, thyristor semi-controlled mode, and switch reverse parallel mode. The switching module is specifically used for: Construct a general matrix model for the bridge arm switches of the converter; The switching mode of the general matrix model is determined based on the control signal, and the dynamic element state variables are analyzed through the general matrix model to generate switching voltage and switching state commands. The switching modes include full control mode, no control mode, thyristor semi-control mode, and switch reverse parallel mode; The neutral point voltage solving module is used to construct a neutral point voltage model for the three-phase rectifier or inverter circuit based on the switching voltage and the switching state command, and to solve for the neutral point voltage. Specifically, the neutral point voltage solving module is used for: Based on the switching voltage and the switching state command, construct a neutral point voltage model for a three-phase rectifier or inverter circuit; With all three phases on, the neutral point voltage model is solved to obtain the full conduction voltage; In the case of three-phase non-fully conducting, a two-phase switch conduction model is constructed and the neutral point voltage model is solved to obtain the non-fully conducting voltage. The fully on voltage and the non-fully on voltage constitute the neutral point voltage; The power supply module is used to provide different power supply voltages for the neutral point voltage solving module. The power supply voltage includes three-phase AC voltage and DC voltage, and the amplitude, step size, frequency and initial value of the power supply voltage can be adjusted.

2. The universal reconfigurable simulation system for power electronic converters according to claim 1, characterized in that, The power module is also used for: Select initial values ​​for the three-phase AC voltage; Select the three-phase amplitude and DC voltage amplitude for the power supply voltage.

3. The universal reconfigurable simulation system for power electronic converters according to claim 1, characterized in that, Also includes: Connection relationship module; The connection module is used to connect the dynamic element module, the switch module, the neutral point voltage calculation module, and the power supply module to realize closed-loop communication and electrical quantity interaction, and generate a connection mathematical model.

4. The universal reconfigurable simulation system for power electronic converters according to claim 1, characterized in that, The dynamic element module includes 12 dynamic elements; The switching module includes 12 selectable switches, which include diode switches, fully controlled switches, and semi-controlled thyristor switches. The power module includes a three-phase AC power supply, two DC power supplies, and a gain module.

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