A converter control method and system for a new energy converter

Abstract

This disclosure provides a commutation control method for a new energy converter, comprising: establishing an equivalent switching vector in the current direction of an initial switching vector; identifying the switching states of multiple IGBTs between the initial switching vector and the target switching vector; and obtaining the inserted switching vector through a bit-by-bit logic operation method. The equivalent switching vector utilizes the anti-parallel diodes of the IGBTs to create identical current paths. This disclosure eliminates pulses caused by deadbands, is easy to implement, requires less switching load, and does not increase the number of switching actions. Using the equivalent switching vector, switching actions can be performed safely without causing short circuits in complementary switches and reducing voltage spikes during switching state transitions. Furthermore, this method does not increase the number of switching actions and has broad engineering application prospects.

Description

Technical Field

[0001] This disclosure relates to the field of power system operation and control technology, and in particular to a converter control method and system for a new energy converter. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] Renewable energy converters have wide applications in industrial drives and renewable energy generation, especially in medium-voltage high-power systems. Renewable energy converters have a relatively small number of components and can effectively balance capacitor voltages over a wide range of fundamental frequencies and modulation indices. However, the complementary switching in renewable energy converters requires PWM dead time to prevent breakdown, which can lead to large voltage spikes. These dead-time-induced spikes can have an amplitude of several output voltage levels, while their duration is the same as the dead time. In the long run, large voltage spikes can cause partial discharges, the effects of which can accumulate and lead to insulation failures. Industry and academia agree that limiting voltage spikes and corresponding partial discharges is crucial.

[0004] Voltage spikes caused by dead zones are difficult to mitigate by improving bus design or adding buffers, and voltage spike filters increase the cost of high-power applications. For renewable energy converters, it is difficult to reduce or eliminate voltage spikes by creating commutation paths, and these spikes can alter the current and voltage stress on power devices. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this disclosure provides a commutation control method and system for a new energy converter, which suppresses induced voltage spikes during the commutation process of the new energy converter, eliminates pulses caused by dead zones, is easy to implement, requires less computational burden, does not increase the number of switching actions, and has broad prospects for engineering applications.

[0006] To achieve the above objectives, the present disclosure adopts the following technical solution:

[0007] The first aspect of this disclosure provides a commutation control method for a new energy converter.

[0008] A commutation control method for a new energy converter includes:

[0009] Obtain the initial switching vector and output voltage level of the renewable energy converter.

[0010] Establish the equivalent switching vector of the initial switching vector in the current direction;

[0011] Find the switching states of multiple IGBTs between the initial switching vector and the target switching vector;

[0012] The inserted switch vector is obtained based on the equivalent switch vector and switch state, and through bit-by-bit logic operation.

[0013] The inserted switch vector is input to the new energy converter controller to complete the commutation process.

[0014] Furthermore, the equivalent switching vector utilizes the anti-parallel diodes of the IGBT to create the same current path.

[0015] Furthermore, the equivalent switching vector is obtained by performing a bitwise XOR operation on the initial switching vector and the current vector created by the integrated IGBT and the anti-parallel diode.

[0016] Furthermore, the switching states of the plurality of IGBTs are specifically the switching vector between the initial switching vector and the target switching vector.

[0017] Furthermore, the switch vector is obtained by a bitwise XOR operation between the initial switch vector and the target switch vector.

[0018] Furthermore, the control method provides a commutation path by controlling the IGBT switch.

[0019] Furthermore, the switching path is executed within one bridge arm.

[0020] The second aspect of this disclosure provides a converter control system for a new energy converter.

[0021] A converter control system for a new energy converter includes:

[0022] The data acquisition module is configured to acquire the initial switching vector and output voltage level of the renewable energy converter;

[0023] The equivalent vector module is configured to establish an equivalent switching vector of the initial switching vector in the current direction.

[0024] The switching vector module is configured to find the switching states of multiple IGBTs between the initial switching vector and the target switching vector;

[0025] The logic operation module is configured to obtain the inserted switch vector based on the equivalent switch vector and the switch state, and through a bit-by-bit logic operation method.

[0026] The third aspect of this disclosure provides a medium having a program stored thereon, which, when executed by a processor, implements the steps of a new energy converter converter control method as described in the first aspect of this disclosure.

[0027] The fourth aspect of this disclosure provides an electronic device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of a new energy converter converter control method as described in the first aspect of this disclosure.

[0028] Compared with the prior art, the beneficial effects of this disclosure are:

[0029] The commutation method described in this disclosure uses bitwise logical operations to implement the commutation steps. Using this method, the switching vector during the commutation steps can be directly obtained without pre-programming specific commutation steps.

[0030] This disclosure eliminates pulses caused by deadbands, is easy to implement, requires less switching overhead, and does not increase the number of switching actions. Using an equivalent switching vector, switching actions can be performed safely without causing short circuits in complementary switches and reducing voltage spikes during switching state transitions. Furthermore, this method does not increase the number of switching actions and has broad engineering application prospects. Attached Figure Description

[0031] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0032] Figure 1 This is a schematic diagram of the topology of the new energy converter provided in Embodiment 1 of this disclosure.

[0033] Figure 2 This is a schematic diagram of the current path and output voltage generated when the switching vector changes from state 4B to state 3B. Detailed Implementation

[0034] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0035] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0036] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0037] Where there is no conflict, the embodiments and features described herein can be combined with each other.

[0038] Example 1:

[0039] like Figure 1 As shown, Embodiment 1 of this disclosure provides a commutation control method for a new energy converter, including the following:

[0040] Obtain the initial switching vector and output voltage level of the renewable energy converter.

[0041] Establish the equivalent switching vector of the initial switching vector in the current direction;

[0042] Find the switching states of multiple IGBTs between the initial switching vector and the target switching vector;

[0043] The inserted switch vector is obtained based on the equivalent switch vector and switch state, and through bit-by-bit logic operation.

[0044] The inserted switch vector is input to the new energy converter controller to complete the commutation process.

[0045] Furthermore, the equivalent switching vector utilizes the anti-parallel diodes of the IGBT to create the same current path.

[0046] Furthermore, the equivalent switching vector is obtained by performing a bitwise XOR operation on the initial switching vector and the current vector created by the integrated IGBT and the anti-parallel diode.

[0047] Furthermore, the switching states of the plurality of IGBTs are specifically the switching vector between the initial switching vector and the target switching vector.

[0048] Furthermore, the switch vector is obtained by a bitwise XOR operation between the initial switch vector and the target switch vector.

[0049] Furthermore, the control method provides a commutation path by controlling the IGBT switch.

[0050] Furthermore, the switching path is executed within one bridge arm.

[0051] Specifically:

[0052] The structure of the new energy converter, which includes six pairs of complementary switches, is shown in the attached figure. Figure 1 As shown. Generally, the switch is an IGBT with an integrated anti-parallel diode. Table 1 lists the applicable switch vectors and output voltage levels. The switch vector is a binary code representing the switch state. The new energy converter has two floating capacitors per phase and a total of three split DC capacitors. During the transition, S1 and... S2 and …S6 and Complementary switches must never be activated simultaneously. In practice, when complementary switches need to change their on / off states, a dead time must be inserted, thus delaying the activation action and prioritizing the deactivation action.

[0053] Table 1 Applicable Switching States for New Energy Converters

[0054]

[0055]

[0056] The switching between state 4B and state 3B under positive current direction is described as an example. Of course, there are similar commutation paths in other states.

[0057] Step one: Turn off the switch with the anti-parallel diode to ensure the supplied current path remains unchanged. From Figure 2 As can be seen from this, the switch and In step one, the IGBT is turned off. Due to the presence of the diode, the current path remains unchanged, resulting in the same output voltage as the initial switching vector. This step lasts for 2 microseconds to ensure the IGBT is fully turned off.

[0058] Step two, turn on the complementary part of the switch that was turned off in step one. Because S5 was already closed in step one. Turn on switches S1, S2, and... Simultaneously, switch S3, which provides the same current path as the target switching vector using a diode, is turned off. If the turn-off and turn-on operations can occur simultaneously, the current commutation path will seamlessly switch from the initial path to the target path. This step also lasts for 2 microseconds to ensure that the turn-off operation can be completed.

[0059] Finally, the target switching vector is applied and input to the controller of the renewable energy converter to complete the commutation process. In this example, the switch... In the final step, it is turned on. Besides this example, all other switch combinations can also find the commutation path for the renewable energy converter under both positive and negative current conditions. The same process applies to all state switching.

[0060] Two commutation steps are inserted between the initial switching vector and the target switching vector, and the commutation path differs for different state transitions. To simplify the implementation of the commutation scheme, this patent proposes a bit-by-bit logic operation method to implement the commutation steps. Using this method, the switching vector during the commutation steps can be obtained directly without pre-programming specific commutation steps.

[0061] Using this method, the switching vectors in steps one and two can be obtained as follows:

[0062] "

[0063] 1. Obtain the equivalent switching vector SV0 of the initial switching vector SV0 in the current direction. Since SV0 utilizes the anti-parallel diode of the IGBT to create the same current path, we can obtain:

[0064]

[0065] in, This indicates a bitwise XOR operation;

[0066] SV dp The current vector created for the integrated IGBT and anti-parallel diode is determined by the output current i. o Direction determines:

[0067]

[0068] 2. Find the switching vector SV between the initial switching vector SV0 and the target switching vector SV3. sw Applying binary arithmetic, SV sw It can be represented as:

[0069]

[0070] in, This indicates a bitwise XOR operation;

[0071] 3. The switching vector in step one is defined as SV1, from which we can obtain:

[0072] SV x =SV′0&SV sw

[0073] SV1 = SV0 & (~SV) x )

[0074] Where & represents bitwise AND operation; ~ represents bitwise NOT operation;

[0075] 4. The switching vector in step two is defined as SV2, from which we can obtain:

[0076]

[0077] SV2 = SV y &SV3

[0078] in, The bitwise XOR operation is represented by '&'; the bitwise AND operation is represented by '&'.

[0079] Therefore, the inserted switching vector SV2 can be obtained. The target switching vector is then input to the controller of the renewable energy converter to complete the commutation process.

[0080] Example 2.

[0081] A converter control system for a new energy converter includes:

[0082] The data acquisition module is configured to acquire the initial switching vector and output voltage level of the renewable energy converter;

[0083] The equivalent vector module is configured to establish an equivalent switching vector of the initial switching vector in the current direction.

[0084] The switching vector module is configured to find the switching states of multiple IGBTs between the initial switching vector and the target switching vector;

[0085] The logic operation module is configured to obtain the inserted switch vector based on the equivalent switch vector and the switch state, and through a bit-by-bit logic operation method.

[0086] Example 3.

[0087] A medium having a program stored thereon, which, when executed by a processor, implements the steps of a new energy converter converter control method as described in the first aspect of this disclosure.

[0088] Example 4.

[0089] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of a new energy converter converter control method as described in the first aspect of this disclosure.

[0090] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, systems, or computer program products. Therefore, this disclosure can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, this disclosure 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 and optical storage) containing computer-usable program code.

[0091] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. 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, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0092] 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 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0093] 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 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0094] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0095] The above description is merely a preferred embodiment of this disclosure and is not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A method for commutation control of a new energy converter, comprising: obtaining an initial switching vector and an output voltage level of the new energy converter; An initial switching vector is established, and an equivalent switching vector in the direction of the current is established An equivalent switching vector in the direction of the current is established Since The same current path is created using the anti-parallel diode of the IGBT, resulting in: wherein denotes a bitwise XOR operation; Current vector created for the integrated IGBT and antiparallel diode by the output current Direction decision: ； finding switching states of a plurality of IGBTs between the initial switching vector and a target switching vector, wherein the switching states of the plurality of IGBTs are switching vectors between the initial switching vector and the target switching vector; In particular: find the switching vector between the initial switching vector and the target switching vector Apply binary operations, represented as:​ wherein denotes a bitwise XOR operation; inserting two commutation steps between the initial switching vector and the target switching vector, and the commutation paths are different for different state switches; wherein, step one, closing the switches with anti-parallel diodes; step two, opening the complementary part of the switches closed in step one; According to the equivalent switching vector and switching state, and through the bit-by-bit logical operation method, the inserted switching vector is obtained; specifically, the switching vector of step one is defined as , and the following is obtained: wherein denotes a bitwise AND operation; denotes a bitwise NOT operation; The switching vector of step two is defined as , which gives: wherein represents a bitwise XOR operation; represents a bitwise AND operation; From this, the inserted switching vector ; completing the commutation control according to the inserted switching vectors.

2. The method of claim 1, wherein the method further comprises: The equivalent switching vector uses the anti-parallel diodes of the IGBTs to create the same current path.

3. The method of claim 1, wherein the method further comprises: The equivalent switching vector is obtained by performing a bitwise XOR operation on the initial switching vector and the current vector created by the integrated IGBTs and anti-parallel diodes.

4. The method of claim 1, wherein the method further comprises: The switching vector is obtained by performing a bitwise XOR operation on the initial switching vector and the target switching vector.

5. The method of claim 4, wherein the method further comprises: The control method provides a commutation path by controlling the IGBT switches.

6. The method of claim 5, wherein the method further comprises: The commutation path is performed within one bridge arm.

7. A new energy converter commutation control system, characterized by, comprising: a data acquisition module configured to obtain an initial switching vector and an output voltage level of the new energy converter; An equivalent vector module configured to establish an equivalent switching vector in the current direction of an initial switching vector, the initial switching vector The equivalent switching vector in the current direction Since Using the anti-parallel diode of the IGBT to create the same current path, we get: wherein denotes a bitwise XOR operation; Current vector created for the integrated IGBT and antiparallel diode by the output current Direction determination: ； a switching vector module configured to find switching states of a plurality of IGBTs between the initial switching vector and a target switching vector, wherein the switching states of the plurality of IGBTs are switching vectors between the initial switching vector and the target switching vector; Specifically: Find the initial switching vector and target switch vector Switching vectors between Applying binary operations, Represented as: wherein denotes a bitwise XOR operation; a logic operation module configured to obtain the inserted switching vectors according to the equivalent switching vectors and the switching states by a bitwise logic operation method; inserting two commutation steps between the initial switching vector and the target switching vector, and the commutation paths are different for different state switches; wherein, step one, closing the switches with anti-parallel diodes; step two, opening the complementary part of the switches closed in step one; According to the equivalent switching vector and switching state, and through the bit-by-bit logical operation method, the inserted switching vector is obtained; specifically, the switching vector of step one is defined as , and the following is obtained: wherein denotes a bitwise AND operation; denotes a bitwise NOT operation; The switching vector of step two is defined as , which gives: wherein represents a bitwise XOR operation; represents a bitwise AND operation; From this, the inserted switching vector is obtained.

8. A computer-readable storage medium having stored thereon a program, characterized in that, the program is executed by the processor to realize a new energy converter commutation control method according to any one of claims 1-6.

9. An electronic device comprising a memory, a processor, and a program stored on the memory and executable on the processor, characterized in that, The processor executes the program to realize a new energy converter commutation control method according to any one of claims 1-6.

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