Multi-vector control method and system for three-level inverter based on sector reconstruction

Abstract

The present application relates to control software technology, in particular to a kind of sector reconstruction-based three-level inverter multi-vector control method and system.First, run multi-vector control algorithm, obtain original vector sequence and original action time.According to hamming distance constraint reordering, the hamming distance of adjacent voltage vectors is not greater than 1, to obtain safe vector sequence.Then check the action time, and the time less than the minimum safe pulse width threshold is forced to rise.Subsequently, time window compensation is carried out, and the action time of the vector not raised is compressed in equal proportion, so that the sum is equal to the switching period, to obtain the final action time.Finally, pulse width modulation pulse is generated based on safe vector sequence and final action time and issued, which can improve the safety, reliability and output power quality of inverter operation.

Description

Technical Field

[0001] This invention relates to the field of control software technology, and in particular to a multi-vector control method and system for a three-level inverter based on sector reconstruction. Background Technology

[0002] Multi-vector control methods for three-level inverters are widely used in high-performance power electronics. In existing technologies, such as CN112821816A, dangerous direct PN switching can be avoided by constraining the absolute value of the change in each phase of adjacent switch states to no more than 1 during the vector selection phase. Furthermore, as described in CN115133798A, a fixed switching frequency can be achieved while reducing common-mode voltage by synthesizing virtual vectors through discrete space vector modulation and designing a fixed switching sequence.

[0003] However, the existing technologies still have the following shortcomings: First, they only use safety constraints as the selection criteria for vectors, without reordering and optimizing existing vector sequences, making it difficult to minimize switching losses while ensuring safety. Second, they lack a systematic processing mechanism for extremely narrow pulses; when the calculated vector action time is less than the minimum safe pulse width of the power device, direct transmission can lead to drive failure or output distortion. Therefore, a sequence optimization and narrow pulse suppression method that balances hardware safety and modulation performance is urgently needed. Summary of the Invention

[0004] This invention addresses the problem in existing technologies that cannot simultaneously ensure hardware security and modulation performance by providing a multi-vector control method and system for three-level inverters based on sector reconstruction.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: In a first aspect, the present invention provides a multi-vector control method for a three-level inverter based on sector reconstruction, comprising: acquiring the original vector sequence and its corresponding original action time; The original vector sequence is reordered based on the Hamming distance constraint to obtain the reordered safe vector sequence. The Hamming distance is the number of phases with different states in the three-phase switching states of any two voltage vectors. The Hamming distance constraint requires that the Hamming distance between any two adjacent voltage vectors in the safe vector sequence is not greater than 1. A threshold check is performed on the time-subtracted action time of each voltage vector in the safety vector sequence. The time-subtracted action time of those voltage vectors that are less than the minimum safety pulse width threshold is forcibly increased to the minimum safety pulse width threshold to obtain the stretched action time. The time of action after stretching is compensated by time window. The time of action of the voltage vector that is not forcibly boosted is compressed proportionally so that the sum of the time of action of all voltage vectors is equal to the switching cycle, and the final time of action is obtained. A pulse width modulation pulse is generated based on the security vector sequence and the final action time, and then sent to the driving circuit.

[0006] Optionally, obtain the original vector sequence and its corresponding original action time, including: A multi-vector control algorithm is run to obtain the set of voltage vectors to be used in the current control cycle. The set of voltage vectors includes at least two voltage vectors, each corresponding to a set of three-phase switch states. Obtain the action time corresponding to each voltage vector in the voltage vector set, wherein the sum of each action time is equal to the switching cycle, and the arrangement order of each voltage vector in the voltage vector set constitutes the original vector sequence.

[0007] Optionally, the original vector sequence is reordered based on Hamming distance constraints to obtain a reordered safe vector sequence, including: Extract all non-repeating voltage vectors from the original vector sequence to form a candidate vector set; Using voltage vectors in the candidate vector set as nodes and Hamming distance between any two voltage vectors as edge weights, the shortest path through all nodes is solved to obtain the sequence with the minimum sum of Hamming distances between adjacent nodes, which is used as the initial safe sequence. Determine whether there are adjacent voltage vector pairs with a Hamming distance greater than 1 in the initial safety sequence. If so, insert an intermediate vector between the adjacent voltage vector pairs with a Hamming distance greater than 1, so that the Hamming distance between all adjacent voltage vectors in the inserted sequence is not greater than 1, and obtain the safety vector sequence. The duration of the inserted intermediate vector is assigned to a preset value, and the corresponding time is subtracted from the duration of the original two adjacent voltage vectors, so that the sum of the durations of all voltage vectors is equal to the switching cycle.

[0008] The method further includes, after inserting an intermediate vector between adjacent voltage vector pairs with a Hamming distance greater than 1, deducting the duration of the intermediate vector from the duration of the original two adjacent voltage vectors proportionally, and ensuring that the remaining duration of the original two adjacent voltage vectors is reduced proportionally after the deduction, so that the volt-second integral vector sum of the original two adjacent voltage vectors before and after the insertion of the intermediate vector remains unchanged in space.

[0009] The intermediate vector is selected from the following two types of vectors: a zero vector in which all three-phase switch states are 0, or a transition vector in which the Hamming distance to the two adjacent voltage vectors is 1.

[0010] Optionally, a threshold check is performed on the time-subtracted action time of each voltage vector in the safety vector sequence, and the time-subtracted action time of those less than the minimum safe pulse width threshold is forcibly increased to the minimum safe pulse width threshold to obtain the stretched action time, including: A preset minimum safe pulse width threshold is provided, wherein the minimum safe pulse width threshold is greater than or equal to the minimum reliable turn-on pulse width of the power switch. Iterate through each voltage vector in the safety vector sequence and obtain the action time corresponding to the voltage vector after time subtraction; If the time-deducted duration is greater than or equal to the minimum safe pulse width threshold, then the stretched duration of the voltage vector is set to be equal to the time-deducted duration. If the duration of action after time deduction is less than the minimum safe pulse width threshold, then the duration of action after stretching the voltage vector is set to be equal to the minimum safe pulse width threshold.

[0011] Optionally, time window compensation is performed on the stretched action time by proportionally compressing the action time of the voltage vectors that were not forcibly boosted, so that the sum of the action times of all voltage vectors equals the switching cycle, thus obtaining the final action time, including: Calculate the sum of the duration increments of all forced boosted voltage vectors, where the duration increment is the difference between the minimum safe pulse width threshold and the duration after time subtraction. The sum of the effective times of all voltage vectors that were not forcibly boosted, after time subtraction, is obtained as the total compressible time. If the total compressible time is greater than zero, then the compression ratio factor is calculated. The compression ratio factor is equal to the ratio of the total compressible time minus the sum of the action time increments to the total compressible time. The final duration of each voltage vector that is not forcibly boosted is set as the compression factor multiplied by the duration of the voltage vector after time subtraction. The final duration of action of each voltage vector that will be forcibly boosted is set as the minimum safe pulse width threshold.

[0012] This also includes: If the total compressible time is equal to zero, then the final action time of all voltage vectors in the safety vector sequence is scaled proportionally so that the sum of the final action times of all voltage vectors is equal to the switching period.

[0013] Optionally, a pulse width modulation pulse is generated based on the security vector sequence and the final action time, and sent to the driving circuit, including: The three-phase switching state of each voltage vector in the security vector sequence is converted into a comparison value for the corresponding phase; The duration of each voltage vector is determined based on the final action time; Write the comparison value and the duration into the comparison register of the pulse width modulation peripheral; The drive pulse is generated by the pulse width modulation peripheral to control the turn-on and turn-off of the power switch.

[0014] Secondly, the present invention provides a multi-vector control system for a three-level inverter based on sector reconfiguration, comprising: The raw information acquisition module is used to acquire the raw vector sequence and its corresponding raw action time; The vector sequence rearrangement module is used to rearrange the original vector sequence based on the Hamming distance constraint to obtain the rearranged safe vector sequence. The Hamming distance is the number of phases with different states in the three-phase switching states of any two voltage vectors. The Hamming distance constraint requires that the Hamming distance between any two adjacent voltage vectors in the safe vector sequence is not greater than 1. The action time stretching module is used to perform threshold verification on the action time of each voltage vector in the safety vector sequence after time subtraction, and to forcibly increase the action time after time subtraction that is less than the minimum safety pulse width threshold to the minimum safety pulse width threshold, so as to obtain the stretched action time. The action time compensation module is used to perform time window compensation on the action time after stretching. By proportionally compressing the action time of the voltage vector that was not forcibly boosted, the sum of the action times of all voltage vectors is made equal to the switching cycle, thus obtaining the final action time. The modulation pulse generation module is used to generate a pulse width modulation pulse based on the security vector sequence and the final action time, and send it to the driving circuit.

[0015] By implementing this invention, it is possible to obtain the original vector sequence and its corresponding original action time; accurately obtain the original vector and time parameters required for inverter control, ensure that subsequent optimization is based on real control requirements, avoid modulation failure due to data loss or deviation, and provide a data foundation for safe vector sorting and narrow pulse processing.

[0016] By implementing this invention, the original vector sequence can be reordered based on Hamming distance constraints to obtain a reordered safe vector sequence. This avoids the hardware risks of direct switching of PN transistors from the source, reduces the frequency of switching action and switching losses, and achieves optimal sequence while ensuring hardware safety, compared to the traditional method of only selecting vectors. This balances safety and control efficiency.

[0017] By implementing this invention, it is possible to perform threshold verification on the time-subtracted action time of each voltage vector in the safety vector sequence, and to forcibly increase the time-subtracted action time of those less than the minimum safe pulse width threshold to the minimum safe pulse width threshold, thereby obtaining the stretched action time; completely solve the problems of drive failure and output waveform distortion caused by narrow pulses, ensure reliable turn-on and turn-off of power switching transistors, avoid hardware damage risks, and improve the inverter's operational stability and output waveform quality.

[0018] By implementing this invention, time window compensation can be achieved for the stretched action time. By proportionally compressing the action time of the voltage vector that was not forcibly boosted, the sum of the action times of all voltage vectors is made equal to the switching cycle, thus obtaining the final action time. While repairing narrow pulses, the total control cycle remains unchanged, ensuring volt-second balance and accurate output vector direction, avoiding modulation errors caused by time imbalance, and balancing hardware safety and control accuracy.

[0019] By implementing this invention, it is possible to generate pulse width modulation pulses based on the safety vector sequence and the final action time, and send them to the drive circuit; to fully connect the control algorithm and hardware drive, so that the effects of sequence optimization and narrow pulse suppression are directly reflected in the power device control, ensuring the stable, efficient and safe operation of the inverter.

[0020] In summary, by implementing this invention, hardware safety protection and modulation performance optimization can be achieved simultaneously in the control of three-level inverters. This not only eliminates dangerous switching states and drive failures and waveform distortions caused by narrow pulses, but also minimizes switching losses, ensures volt-second balance and stable switching cycles, and comprehensively improves the inverter's operational safety, reliability, and output power quality to adapt to high-performance power electronics application scenarios. Attached Figure Description

[0021] Figure 1 A flowchart illustrating the multi-vector control method for a three-level inverter based on sector reconstruction provided by this invention; Figure 2 A schematic diagram of the structure of the three-level inverter multi-vector control system based on sector reconstruction provided by the present invention.

[0022] In the attached diagram, the components represented by each number are as follows: The module includes: 11 for acquiring raw information, 12 for rearranging vector sequences, 13 for stretching action time, 14 for compensating action time, and 15 for generating modulation pulses. Detailed Implementation

[0023] Example 1, as Figure 1 As shown, this embodiment of the invention provides a multi-vector control method for a three-level inverter based on sector reconstruction, including: S100: Obtain the original vector sequence and its corresponding original action time; S200: Reorder the original vector sequence based on the Hamming distance constraint to obtain the reordered safe vector sequence, wherein the Hamming distance is the number of phases with different states in the three-phase switching states of any two voltage vectors, and the Hamming distance constraint requires that the Hamming distance between any two adjacent voltage vectors in the safe vector sequence is not greater than 1; S300: Perform threshold verification on the original action time of each voltage vector in the safety vector sequence, and force the original action time that is less than the minimum safety pulse width threshold to be increased to the minimum safety pulse width threshold to obtain the stretched action time; S400: Perform time window compensation on the stretched action time by proportionally compressing the action time of the voltage vector that was not forcibly boosted, so that the sum of the action times of all voltage vectors equals the switching cycle, and obtain the final action time. S500: Generate a pulse width modulation pulse based on the security vector sequence and the final action time, and send it to the driving circuit.

[0024] In step S100 of this embodiment, obtaining the original vector sequence and its corresponding original action time includes: A multi-vector control algorithm is run to obtain the set of voltage vectors to be used in the current control cycle. The set of voltage vectors includes at least two voltage vectors, each corresponding to a set of three-phase switch states. Obtain the action time corresponding to each voltage vector in the voltage vector set, wherein the sum of each action time is equal to the switching cycle, and the arrangement order of each voltage vector in the voltage vector set constitutes the original vector sequence.

[0025] In step S100 of this application embodiment, the purpose of the above step is to provide initial control data for the multi-vector control method of three-level inverter based on sector reconstruction, determine all voltage vectors used for modulation in the current control cycle, the original action time of each voltage vector, and the initial arrangement order of the vectors, and lay the foundation for subsequent vector sequence reordering, action time threshold verification, time window compensation, and modulation pulse generation.

[0026] To achieve the above objectives, a multi-vector control algorithm must first be run to obtain the set of voltage vectors to be used in the current control cycle. This set of voltage vectors includes at least two voltage vectors, each corresponding to a set of three-phase switch states. According to the preset multi-vector control logic, combined with the current operating conditions of the inverter and the control objectives, all voltage vectors that need to participate in voltage synthesis in this control cycle are calculated to form a voltage vector set. This set contains at least two voltage vectors, and each voltage vector uniquely corresponds to a set of three-phase switch states. The three-phase switch states are used to characterize the on and off combinations of the power switches of each phase of the inverter.

[0027] For example, after running the multi-vector control algorithm in the current control cycle, the set of voltage vectors to be used is obtained. This set contains three voltage vectors: voltage vector V1, voltage vector V2, and voltage vector V3. The three-phase switch states corresponding to voltage vector V1 are P, O, and N; the three-phase switch states corresponding to voltage vector V2 are O, O, and N; and the three-phase switch states corresponding to voltage vector V3 are O, N, and N.

[0028] The preset multi-vector control logic is a control algorithm pre-written into the inverter controller, used to calculate the required voltage vector based on the current operating conditions. Specifically, the controller collects feedback signals such as motor speed, current, DC-side voltage, and midpoint potential in real time, substitutes them into the deadbeat-free model predictive control algorithm, and calculates the voltage vector and its duration to be output in the current cycle according to volt-second balance and midpoint balance requirements, directly obtaining the voltage vector set.

[0029] The deadbeat-free model predictive control algorithm is based on a mathematical model of a three-level inverter and a motor. Using the stator voltage equation and current prediction formula, it directly and analytically calculates the voltage vector and its corresponding duration that minimizes the current tracking error before the start of the next control cycle. The deadbeat-free model predictive control algorithm first establishes a deadbeat constraint on the current, ensuring that the predicted current at the next moment equals the given current. Then, combined with the total duration constraint of the switching cycle, it solves for the set of voltage vectors that meet the output requirements and the original duration of each vector. This eliminates the need for traversal optimization, resulting in fast calculation and high tracking accuracy.

[0030] Specifically, the deadbeat-free model predictive control algorithm is built into the controller and does not require external acquisition. During operation, the controller collects feedback quantities such as inverter three-phase current, DC side voltage, and motor position in real time, substitutes them into the stator voltage equation and current prediction formula, and directly performs analytical calculations according to the deadbeat constraint of the current to obtain the voltage vector set and the original action time of each vector for the current control cycle. The entire process is automatically executed by the controller chip.

[0031] Then, it is necessary to obtain the action time corresponding to each voltage vector in the voltage vector set, wherein the sum of each action time is equal to the switching cycle, and the arrangement order of each voltage vector in the voltage vector set constitutes the original vector sequence.

[0032] Based on the calculation results of the multi-vector control algorithm, the duration for which each voltage vector in the voltage vector set needs to be continuously output within the switching cycle is determined, i.e., the original operating time. The sum of the original operating times of all voltage vectors equals the set switching cycle.

[0033] For example, if the switching period is set to 100 microseconds, and the voltage vector set includes voltage vector V1, voltage vector V2, and voltage vector V3, the calculated original action time corresponding to voltage vector V1 is 30 microseconds, the original action time corresponding to voltage vector V2 is 50 microseconds, and the original action time corresponding to voltage vector V3 is 20 microseconds. 30 microseconds plus 50 microseconds plus 20 microseconds equals 100 microseconds, which satisfies the requirement that the sum of the action times equals the switching period.

[0034] The switching period is a fixed duration of one complete pulse width modulation cycle of the three-level inverter, determined by the controller clock and preset PWM peripheral parameters. For example, if the switching frequency is set to 10kHz, the switching period is equal to 1 divided by 10kHz, which is 100 microseconds. The controller directly reads this fixed value as the total duration of the current control cycle.

[0035] Finally, the natural order of the voltage vectors in the voltage vector set is directly adopted as the initial vector sequence without optimization and safety constraints, i.e., the original vector sequence.

[0036] For example, the natural order of voltage vectors in the voltage vector set is voltage vector V1, voltage vector V2, voltage vector V3, which constitutes the original vector sequence of this control cycle.

[0037] In step S200 of this embodiment, the original vector sequence is reordered based on Hamming distance constraints to obtain a reordered secure vector sequence, including: Extract all non-repeating voltage vectors from the original vector sequence to form a candidate vector set; Using voltage vectors in the candidate vector set as nodes and Hamming distance between any two voltage vectors as edge weights, the shortest path through all nodes is solved to obtain the sequence with the minimum sum of Hamming distances between adjacent nodes, which is used as the initial safe sequence. Determine whether there are adjacent voltage vector pairs with a Hamming distance greater than 1 in the initial safety sequence. If so, insert an intermediate vector between the adjacent voltage vector pairs with a Hamming distance greater than 1, so that the Hamming distance between all adjacent voltage vectors in the inserted sequence is not greater than 1, and obtain the safety vector sequence. The duration of the inserted intermediate vector is assigned to a preset value, and the corresponding time is subtracted from the duration of the original two adjacent voltage vectors, so that the sum of the durations of all voltage vectors is equal to the switching cycle.

[0038] In step S200 of this application embodiment, the purpose of the above step is to reorder the original vector sequence based on the Hamming distance constraint and insert intermediate vectors to obtain a safe vector sequence in which the Hamming distance between adjacent voltage vectors is not greater than 1, while keeping the sum of the action time of all voltage vectors equal to the switching period, so as to provide a vector sequence that meets the hardware safety requirements for subsequent action time processing.

[0039] To achieve the above objective, it is first necessary to extract all non-repeating voltage vectors from the original vector sequence to form a candidate vector set; That is, traverse every voltage vector in the original vector sequence, remove duplicate voltage vectors, and combine all the remaining unique voltage vectors to form a candidate vector set containing only non-repeating voltage vectors.

[0040] For example, if the original vector sequence is voltage vector V1, voltage vector V2, voltage vector V3, then the non-repeating voltage vectors V1, V2, and V3 are extracted to form a candidate vector set.

[0041] Next, using the voltage vectors in the candidate vector set as nodes and the Hamming distance between any two voltage vectors as edge weights, the shortest path through all nodes is solved to obtain the sequence with the minimum sum of Hamming distances between adjacent nodes, which is used as the initial safe sequence. Each voltage vector in the candidate vector set is treated as an independent node. The Hamming distance between the voltage vectors corresponding to any two nodes is calculated. The Hamming distance is the number of phases that are different in the three-phase switching states of the two voltage vectors. The Hamming distance is used as the edge weight between the two nodes. All nodes are traversed by the shortest path algorithm to obtain the vector arrangement order with the smallest sum of Hamming distances between adjacent nodes. This vector arrangement order is the initial safe sequence.

[0042] For example, the candidate vector set is voltage vector V1, voltage vector V2, and voltage vector V3. The Hamming distance between voltage vector V1 and V2 is 1, the Hamming distance between voltage vector V2 and V3 is 1, and the Hamming distance between voltage vector V1 and V3 is 2. Solving for the shortest path yields the initial safe sequence of voltage vector V1, voltage vector V2, and voltage vector V3, with the sum of the Hamming distances between adjacent nodes being 2.

[0043] Then, it is determined whether there are adjacent voltage vector pairs with a Hamming distance greater than 1 in the initial safety sequence. If so, an intermediate vector is inserted between the adjacent voltage vector pairs with a Hamming distance greater than 1, so that the Hamming distance between all adjacent voltage vectors in the inserted sequence is not greater than 1, and the safety vector sequence is obtained. That is, check the Hamming distance value of each pair of adjacent voltage vectors in the initial safety sequence one by one. When it is found that there is a pair of adjacent voltage vectors with a Hamming distance greater than 1, insert an intermediate vector in the middle of the pair of adjacent voltage vectors. After insertion, the Hamming distance of the two pairs of adjacent voltage vectors before and after the position is not greater than 1. After all the positions that do not meet the constraints are processed, the final safety vector sequence is obtained.

[0044] For example, the initial safe sequence is voltage vector V1 and voltage vector V3, with a Hamming distance of 2 between them. After inserting the intermediate vector V2, the sequence becomes voltage vector V1, voltage vector V2, and voltage vector V3. The Hamming distance between voltage vector V1 and V2 is 1, the Hamming distance between voltage vector V2 and V3 is 1, and the Hamming distance between all adjacent voltage vectors is no greater than 1. This sequence is the safe vector sequence.

[0045] Furthermore, the duration of the inserted intermediate vector is allocated to a preset value, and the corresponding time is subtracted from the duration of the original two adjacent voltage vectors, so that the sum of the durations of all voltage vectors is equal to the switching cycle.

[0046] This involves setting a fixed preset duration for the inserted intermediate vector. According to preset rules, the total duration equal to the preset duration of the intermediate vector is deducted from the original durations of the two original adjacent voltage vectors before and after it. The sum of the durations of all voltage vectors after this deduction is consistent with the switching cycle. For example, if the switching cycle is 100 microseconds, the durations of the original adjacent voltage vectors V1 and V3 are 50 microseconds each. An intermediate vector V2 is inserted and assigned a preset duration of 10 microseconds. 5 microseconds are deducted from V1 and V3, resulting in a final duration of 45 microseconds for V1, 10 microseconds for V2, and 45 microseconds for V3, totaling 100 microseconds, which is equal to the switching cycle.

[0047] In step S200 of this application embodiment, after inserting an intermediate vector between adjacent voltage vector pairs with a Hamming distance greater than 1, the method further includes: deducting the action time of the intermediate vector from the action time of the original two adjacent voltage vectors proportionally, and after the deduction, the remaining action time of the original two adjacent voltage vectors is reduced proportionally, so that the volt-second integral vector sum of the original two adjacent voltage vectors before and after inserting the intermediate vector remains unchanged in space.

[0048] In step S200 of this application embodiment, the purpose of the above step is to ensure that the volt-second integral vectors of the original two adjacent voltage vectors before and after the insertion of the intermediate vector remain unchanged in space, while maintaining the sum of the action time of all voltage vectors equal to the switching period.

[0049] To achieve the above objectives, it is necessary to first calculate the required duration of the intermediate vector, then determine the ratio of the original durations of the two adjacent voltage vectors, and subtract the corresponding durations from the original durations of the two adjacent voltage vectors according to the same ratio, so that the remaining durations of the two adjacent voltage vectors after subtraction are completely consistent with the ratio of their original durations. This ensures that the spatial direction of the volt-second integral vector sum does not change, and that the sum of the durations of all voltage vectors is still equal to the switching cycle.

[0050] For example, with a switching cycle of 100 microseconds, the original two adjacent voltage vectors are voltage vector A and voltage vector B. The original duration of voltage vector A is 40 microseconds, and the original duration of voltage vector B is 60 microseconds, with an original duration ratio of 2:3. An intermediate vector C is inserted and its duration is allocated to 10 microseconds. Following the same 2:3 ratio, 4 microseconds are subtracted from voltage vector A and 6 microseconds from voltage vector B. The remaining duration of voltage vector A is 36 microseconds, and the remaining duration of voltage vector B is 54 microseconds, with the remaining duration ratio still 2:3. The volt-second integral vector and spatial direction remain unchanged before and after the insertion of the intermediate vector. The total duration of voltage vector A, voltage vector B, and intermediate vector C remains 100 microseconds, equal to the switching cycle.

[0051] In step S200 of this application embodiment, the intermediate vector is selected from the following two types of vectors: a zero vector in which all three-phase switch states are 0, or a transition vector in which the Hamming distance to the two adjacent voltage vectors is 1.

[0052] In step S200 of this application embodiment, the purpose of the above step is to select an intermediate vector that meets the safety switching requirements between adjacent voltage vector pairs that are inserted with a Hamming distance greater than 1, so as to ensure that the Hamming distance between adjacent voltage vectors after insertion is not greater than 1, satisfy the safety switching constraints of the inverter switching state, and avoid dangerous direct switching.

[0053] To achieve the above objectives, the intermediate vector must first be selected within the aforementioned range. The intermediate vector can only be selected from two types of vectors: the first is the zero vector where all three-phase switching states are 0, and the second is the transition vector where the Hamming distance between the intermediate vector and the two adjacent voltage vectors is equal to 1. After selection, it can be ensured that the switching of adjacent vectors only involves single-phase single-state changes.

[0054] For example, adjacent voltage vectors V1 (three-phase switch states P, O, N) and V3 (three-phase switch states O, N, O) have a Hamming distance of 2. A zero vector with all three phases in switch state O is selected as the intermediate vector. This zero vector has a Hamming distance of 1 with both V1 and V3, satisfying the constraint requirement. As another example, adjacent voltage vectors V_A (switch states P, P, O) and V_B (switch states O, N, N) have a Hamming distance of 3. A transition vector V_M (switch states O, P, O) with a Hamming distance of 1 from both V_A and V_B is selected as the intermediate vector. After insertion, the Hamming distance between all adjacent vectors is no greater than 1, meeting the safety vector sequence requirement.

[0055] In step S300 of this embodiment, a threshold check is performed on the time-subtracted action time of each voltage vector in the safety vector sequence, and the time-subtracted action time of those less than the minimum safe pulse width threshold is forcibly increased to the minimum safe pulse width threshold to obtain the stretched action time, including: A preset minimum safe pulse width threshold is provided, wherein the minimum safe pulse width threshold is greater than or equal to the minimum reliable turn-on pulse width of the power switch. Iterate through each voltage vector in the safety vector sequence and obtain the action time corresponding to the voltage vector after time subtraction; If the time-deducted duration is greater than or equal to the minimum safe pulse width threshold, then the stretched duration of the voltage vector is set to be equal to the time-deducted duration. If the duration of action after time deduction is less than the minimum safe pulse width threshold, then the duration of action after stretching the voltage vector is set to be equal to the minimum safe pulse width threshold.

[0056] In step S300 of this application embodiment, the purpose of the above step is to perform threshold verification on the original action time of each voltage vector in the safety vector sequence, and to force the original action time that is less than the minimum safety pulse width threshold to be increased to the minimum safety pulse width threshold, so as to obtain the stretched action time, avoid the occurrence of extremely narrow pulses that the power switching tube cannot respond reliably, and ensure the safe and stable operation of the drive circuit and power devices.

[0057] To achieve the above objectives, it is first necessary to preset a minimum safe pulse width threshold, wherein the minimum safe pulse width threshold is greater than or equal to the minimum reliable turn-on pulse width of the power switch. Based on the hardware electrical parameters of the power switch used, a fixed minimum safe pulse width threshold is preset. This minimum safe pulse width threshold must be greater than or equal to the minimum reliable turn-on pulse width that the power switch can normally turn on and off, ensuring that the pulse width meets the hardware physical constraints.

[0058] For example, the minimum reliable turn-on pulse width of the selected power switch is 2 microseconds, so the preset minimum safe pulse width threshold is 2 microseconds. This minimum safe pulse width threshold meets the requirement of being greater than or equal to the minimum reliable turn-on pulse width of the power switch.

[0059] Then, each voltage vector in the safety vector sequence is traversed, and the effective time corresponding to the voltage vector after time subtraction is obtained; That is, according to the arrangement order of the safety vector sequence, each voltage vector in the sequence is accessed one by one, and the effective time of each voltage vector after time subtraction is read and recorded in the current control cycle to complete the full sequence coverage data acquisition.

[0060] For example, the safety vector sequence contains three voltage vectors: voltage vector V1, voltage vector V2, and voltage vector V3. After traversing them sequentially, the original action time of voltage vector V1 is found to be 3 microseconds, the original action time of voltage vector V2 is 1 microsecond, and the original action time of voltage vector V3 is 5 microseconds.

[0061] If the time-deducted duration is greater than or equal to the minimum safe pulse width threshold, then the stretched duration of the voltage vector is set to be equal to the time-deducted duration. The action time of the current voltage vector after time subtraction is compared with the minimum safe pulse width threshold. When the original action time is greater than or equal to the minimum safe pulse width threshold, the original action time is retained and used as the action time of the stretched voltage vector.

[0062] For example, the minimum safe pulse width threshold is 2 microseconds, and the original action time of voltage vector V1 is 3 microseconds. Since 3 microseconds is greater than 2 microseconds, the action time of voltage vector V1 after stretching is set to 3 microseconds.

[0063] If the duration of action after time deduction is less than the minimum safe pulse width threshold, then the duration of action after stretching the voltage vector is set to be equal to the minimum safe pulse width threshold.

[0064] The action time of the current voltage vector after time subtraction is compared with the minimum safe pulse width threshold. When the original action time is less than the minimum safe pulse width threshold, the action time of the voltage vector is forcibly increased to the minimum safe pulse width threshold, and this is used as the action time of the stretched voltage vector.

[0065] For example, the minimum safe pulse width threshold is 2 microseconds, and the original action time of voltage vector V2 is 1 microsecond. Since 1 microsecond is less than 2 microseconds, the action time of voltage vector V2 after stretching is set to 2 microseconds.

[0066] In step S400 of this embodiment, time window compensation is performed on the stretched action time. This is achieved by proportionally compressing the action time of the voltage vectors that were not forcibly boosted, so that the sum of the action times of all voltage vectors equals the switching cycle, thus obtaining the final action time. This includes: Calculate the sum of the duration increments of all forced boosted voltage vectors, where the duration increment is the difference between the minimum safe pulse width threshold and the duration after time subtraction. The sum of the effective times of all voltage vectors that were not forcibly boosted, after time subtraction, is obtained as the total compressible time. If the total compressible time is greater than zero, then the compression ratio factor is calculated. The compression ratio factor is equal to the ratio of the total compressible time minus the sum of the action time increments to the total compressible time. The final duration of each voltage vector that is not forcibly boosted is set as the compression factor multiplied by the duration of the voltage vector after time subtraction. The final duration of action of each voltage vector that will be forcibly boosted is set as the minimum safe pulse width threshold.

[0067] In step S400 of this application embodiment, the purpose of the above step is to perform time window compensation on the stretched action time. By proportionally compressing the action time of the voltage vector that has not been forcibly boosted, the sum of the action times of all voltage vectors is made to be strictly equal to the switching cycle, so as to obtain the final action time that meets the modulation requirements, ensuring that the inverter output is stable and meets hardware safety and time constraints.

[0068] To achieve the above objective, it is first necessary to calculate the sum of the action time increments of all the forced boosted voltage vectors, where the action time increment is the difference between the minimum safe pulse width threshold and the action time after time subtraction. First, identify each voltage vector that is forcibly boosted, then subtract the original duration of the corresponding voltage vector from the minimum safe pulse width threshold to obtain the individual duration increment. Finally, add the duration increments of all the forcibly boosted voltage vectors to obtain the sum of duration increments.

[0069] For example, the minimum safe pulse width threshold is 2 microseconds, the original duration of the voltage vector V2 that is forcibly boosted is 1 microsecond, and the duration increment is 2 microseconds minus 1 microsecond equals 1 microsecond. Since there is only one forcibly boosted vector, the sum of the duration increments is 1 microsecond.

[0070] Then, the sum of the action times of all voltage vectors that were not forcibly boosted after time subtraction is obtained as the total compressible time. That is, all voltage vectors in the safety vector sequence that have not been forcibly boosted are selected, and the original action times corresponding to these voltage vectors are added together. The sum is the total amount of compressible time that can be used for compression compensation.

[0071] For example, in the safety vector sequence, voltage vectors V1 and V3 are not forcibly boosted. The original action time of V1 is 3 microseconds and the original action time of V3 is 5 microseconds. The total compressible time is 3 microseconds plus 5 microseconds, which equals 8 microseconds.

[0072] If the total compressible time is greater than zero, then the compression ratio factor is calculated. The compression ratio factor is equal to the ratio of the total compressible time minus the sum of the action time increments to the total compressible time. That is, determine whether the total compressible time is greater than zero. If the condition is met, subtract the sum of the action time increments from the total compressible time, and then divide the calculation result by the total compressible time to obtain the compression ratio factor used for proportional compression.

[0073] For example, if the total compressible time is 8 microseconds and the sum of the action time increments is 1 microsecond, and 8 microseconds is greater than zero, then the compression ratio factor is equal to 8 microseconds minus 1 microsecond divided by 8 microseconds, that is, 7 / 8 equals 0.875.

[0074] Next, the final duration of each voltage vector that was not forcibly boosted is set as the compression factor multiplied by the duration of the voltage vector after time subtraction. That is, the original duration of each voltage vector that is not forcibly boosted is multiplied by the calculated compression factor, and the result is used as the final duration of that voltage vector.

[0075] For example, the original duration of voltage vector V1, which is not forcibly boosted, is 3 microseconds. Multiplying it by the compression factor of 0.875, the final duration is 2.625 microseconds. The original duration of voltage vector V3 is 5 microseconds. Multiplying it by the compression factor of 0.875, the final duration is 4.375 microseconds.

[0076] Finally, the final duration of action of each voltage vector that is forcibly boosted is set as the minimum safe pulse width threshold.

[0077] That is, the voltage vector that is forcibly boosted will no longer be compressed and adjusted, and the minimum safe pulse width threshold will be directly used as the final action time of this type of voltage vector.

[0078] For example, the minimum safe pulse width threshold corresponding to the forcibly boosted voltage vector V2 is 2 microseconds, so the final action time of the voltage vector V2 is set to 2 microseconds.

[0079] In step S400 of the embodiments of this application, the following is also included: If the total compressible time is equal to zero, then the final action time of all voltage vectors in the safety vector sequence is scaled proportionally so that the sum of the final action times of all voltage vectors is equal to the switching period.

[0080] In step S400 of this application embodiment, the purpose of the above step is to perform uniform proportional scaling on the action time of all voltage vectors in the security vector sequence when the total compressible time is equal to zero, so that the sum of the final action time of all voltage vectors is strictly equal to the switching period, ensuring the integrity of the modulation timing and satisfying the hardware security constraints.

[0081] To achieve the above objectives, it is first necessary to determine that the total compressible time is equal to zero, and then calculate the uniform scaling ratio. The scaling ratio is equal to the switching period divided by the sum of the action times of all voltage vectors stretched in the safety vector sequence. Then, the scaling ratio is multiplied by the action time of each voltage vector stretched to obtain the final action time after proportional scaling, ensuring that the sum of all final action times equals the switching period.

[0082] For example, the switching period is 100μs, the safety vector sequence includes voltage vectors V1, V2, and V3, and the extended action times are 2μs, 2μs, and 2μs respectively, with a total of 6μs. The total compressible time is 0.

[0083] Scaling ratio = 100μs ÷ 6μs ≈ 16.6667.

[0084] The final duration of voltage vector V1 = 2μs × 16.6667 ≈ 33.333μs.

[0085] The final duration of voltage vector V2 = 2μs × 16.6667 ≈ 33.333μs.

[0086] The final duration of voltage vector V3 is approximately 33.334 μs, calculated as 2 μs × 16.6667.

[0087] The sum of the three is 100μs, which is consistent with the switching period.

[0088] In step S500 of this embodiment, a pulse width modulation pulse is generated based on the security vector sequence and the final action time, and sent to the driving circuit, including: The three-phase switching state of each voltage vector in the security vector sequence is converted into a comparison value for the corresponding phase; The duration of each voltage vector is determined based on the final action time; Write the comparison value and the duration into the comparison register of the pulse width modulation peripheral; The drive pulse is generated by the pulse width modulation peripheral to control the turn-on and turn-off of the power switch.

[0089] In step S500 of this application embodiment, the purpose of the above steps is to convert the three-phase switching state of the voltage vector into a hardware-recognizable comparison value based on the safety vector sequence and the final action time, and to combine the pulse width modulation peripheral with the duration configuration. The pulse width modulation peripheral generates a drive pulse that meets the requirements and sends it to the drive circuit to achieve precise control of the power switch tube's turn-on and turn-off.

[0090] To achieve the above objective, it is first necessary to convert the three-phase switching state of each voltage vector in the security vector sequence into the comparison value of the corresponding phase. That is, according to the register mapping rules of the pulse width modulation peripheral, the three-phase switch state corresponding to each voltage vector in the security vector sequence is converted into the corresponding digital comparison value of phase A, phase B and phase C. This comparison value is used to match the counting interval of the pulse width modulation counter to determine the level output state.

[0091] For example, in a safety vector sequence, the three-phase switching states of a voltage vector are P, O, and N. According to the pulse width modulation mapping rule of a three-level inverter, after conversion, the comparison value of phase A is a high threshold, the comparison value of phase B is a medium threshold, and the comparison value of phase C is a low threshold.

[0092] In this system, phase A has a high threshold value, corresponding to the P state in the three-phase switching state, representing that the upper bridge arm power switch of that phase is turned on. Phase B has a medium threshold value, corresponding to the O state in the three-phase switching state, representing that neither the upper nor lower bridge arms of that phase are turned on, and it is connected to the DC side midpoint. Phase C has a low threshold value, corresponding to the N state in the three-phase switching state, representing that the lower bridge arm power switch of that phase is turned on. These comparison values, after being written to the pulse width modulation peripheral, can directly generate drive levels that match the switching states. The high, medium, and low thresholds are the count comparison values ​​of the pulse width modulation peripheral counter, calculated by the controller hardware clock and the switching cycle, and are fixedly written into the register for use. The three thresholds can be calculated based on the switching cycle and the number of bits of the PWM counter; they are hardware mapping values ​​determined at the factory by the controller and are used to convert the switching states into executable drive signals.

[0093] The duration of each voltage vector is determined based on the final action time; That is, the final action time obtained after time window compensation and proportional scaling is directly used as the duration for which the voltage vector needs to maintain output within one switching cycle. This duration strictly meets the hardware safety and total time constraints.

[0094] For example, the final duration of a voltage vector after time compensation is 2.625 microseconds, which is the duration of the voltage vector in the current switching cycle.

[0095] Write the comparison value and the duration into the comparison register of the pulse width modulation peripheral; That is, according to the controller hardware drive timing, the comparison values ​​of each phase obtained in the first step and the duration determined in the second step are written into the comparison register and period register corresponding to the pulse width modulation peripheral in sequence, thus completing the hardware configuration of the pulse width modulation output parameters.

[0096] For example, the high threshold of phase A comparison value, the medium threshold of phase B comparison value, the low threshold of phase C comparison value, and the duration of 2.625 microseconds are synchronously written into the comparison register of the pulse width modulation peripheral to complete the parameter loading.

[0097] The drive pulse is generated by the pulse width modulation peripheral to control the turn-on and turn-off of the power switch.

[0098] That is, the pulse width modulation peripheral automatically runs the counting comparison logic based on the comparison value in the comparison register and the duration, outputs a square wave drive pulse that meets the timing and level requirements, transmits the pulse signal to the drive circuit, and then controls the power switching transistors of each phase of the inverter to turn on or off according to the specified state.

[0099] For example, the pulse width modulation peripheral generates a corresponding drive pulse according to the configuration parameters. After receiving the pulse, the drive circuit controls the upper transistor of phase A to be turned on, the upper and lower transistors of phase B to be turned off, and the lower transistor of phase C to be turned on, so as to achieve the specified vector output.

[0100] Example 2, as Figure 2 As shown, based on the same inventive concept as the sector-reconfiguration-based three-level inverter multi-vector control method provided in Embodiment 1, this embodiment of the invention also provides a sector-reconfiguration-based three-level inverter multi-vector control system, including: The original information acquisition module 11 is used to acquire the original vector sequence and its corresponding original action time; Vector sequence rearrangement module 12 is used to rearrange the original vector sequence based on Hamming distance constraints to obtain a rearranged safe vector sequence. The Hamming distance is the number of phases with different states in the three-phase switching states of any two voltage vectors. The Hamming distance constraint requires that the Hamming distance between any two adjacent voltage vectors in the safe vector sequence is not greater than 1. The action time stretching module 13 is used to perform threshold verification on the action time of each voltage vector in the safety vector sequence after time subtraction, and to forcibly increase the action time after time subtraction that is less than the minimum safety pulse width threshold to the minimum safety pulse width threshold to obtain the stretched action time. The action time compensation module 14 is used to perform time window compensation on the action time after stretching. By proportionally compressing the action time of the voltage vector that was not forcibly boosted, the sum of the action times of all voltage vectors is made equal to the switching cycle, and the final action time is obtained. The modulation pulse generation module 15 is used to generate a pulse width modulation pulse based on the security vector sequence and the final action time, and send it to the driving circuit.

[0101] Furthermore, the original information acquisition module 11 includes the following execution steps: A multi-vector control algorithm is run to obtain the set of voltage vectors to be used in the current control cycle. The set of voltage vectors includes at least two voltage vectors, each corresponding to a set of three-phase switch states. Obtain the action time corresponding to each voltage vector in the voltage vector set, wherein the sum of each action time is equal to the switching cycle, and the arrangement order of each voltage vector in the voltage vector set constitutes the original vector sequence.

[0102] Furthermore, the vector sequence rearrangement module 12 includes the following execution steps: Using voltage vectors in the candidate vector set as nodes and Hamming distance between any two voltage vectors as edge weights, the shortest path through all nodes is solved to obtain the sequence with the minimum sum of Hamming distances between adjacent nodes, which is used as the initial safe sequence. Determine whether there are adjacent voltage vector pairs with a Hamming distance greater than 1 in the initial safety sequence. If so, insert an intermediate vector between the adjacent voltage vector pairs with a Hamming distance greater than 1, so that the Hamming distance between all adjacent voltage vectors in the inserted sequence is not greater than 1, and obtain the safety vector sequence. The duration of the inserted intermediate vector is assigned to a preset value, and the corresponding time is subtracted from the duration of the original two adjacent voltage vectors, so that the sum of the durations of all voltage vectors is equal to the switching cycle.

[0103] It also includes: proportionally subtracting the duration of the intermediate vector from the duration of the original two adjacent voltage vectors, and after the subtraction, the remaining duration of the original two adjacent voltage vectors is reduced proportionally, so that the volt-second integral vector sum of the original two adjacent voltage vectors before and after the insertion of the intermediate vector remains unchanged in space.

[0104] The intermediate vector is selected from the following two types of vectors: a zero vector in which all three-phase switch states are 0, or a transition vector in which the Hamming distance to the two adjacent voltage vectors is 1.

[0105] Furthermore, the action time stretching module 13 includes the following execution steps: A preset minimum safe pulse width threshold is provided, wherein the minimum safe pulse width threshold is greater than or equal to the minimum reliable turn-on pulse width of the power switch. Iterate through each voltage vector in the safety vector sequence and obtain the action time corresponding to the voltage vector after time subtraction; If the time-deducted duration is greater than or equal to the minimum safe pulse width threshold, then the stretched duration of the voltage vector is set to be equal to the time-deducted duration. If the duration of action after time deduction is less than the minimum safe pulse width threshold, then the duration of action after stretching the voltage vector is set to be equal to the minimum safe pulse width threshold.

[0106] Furthermore, the action time compensation module 14 includes the following execution steps: Calculate the sum of the duration increments of all forced boosted voltage vectors, where the duration increment is the difference between the minimum safe pulse width threshold and the duration after time subtraction. The sum of the effective times of all voltage vectors that were not forcibly boosted, after time subtraction, is obtained as the total compressible time. If the total compressible time is greater than zero, then the compression ratio factor is calculated. The compression ratio factor is equal to the ratio of the total compressible time minus the sum of the action time increments to the total compressible time. The final duration of each voltage vector that is not forcibly boosted is set as the compression factor multiplied by the duration of the voltage vector after time subtraction. The final duration of action of each voltage vector that will be forcibly boosted is set as the minimum safe pulse width threshold.

[0107] If the total compressible time is equal to zero, then the final action time of all voltage vectors in the safety vector sequence is scaled proportionally so that the sum of the final action times of all voltage vectors is equal to the switching period.

[0108] Furthermore, the modulation pulse generation module 15 includes the following execution steps: The three-phase switching state of each voltage vector in the security vector sequence is converted into a comparison value for the corresponding phase; The duration of each voltage vector is determined based on the final action time; Write the comparison value and the duration into the comparison register of the pulse width modulation peripheral; The drive pulse is generated by the pulse width modulation peripheral to control the turn-on and turn-off of the power switch.

Claims

1. A multi-vector control method for a three-level inverter based on sector reconfiguration, characterized in that, include: Obtain the original vector sequence and its corresponding original action time; The original vector sequence is reordered based on Hamming distance constraints to obtain a reordered safe vector sequence. The time-subtracted duration of each voltage vector in the safety vector sequence is subjected to threshold verification. The time-subtracted duration of the voltage vectors that are less than the minimum safety pulse width threshold is forcibly increased to the minimum safety pulse width threshold to obtain the stretched duration. The time of action after stretching is compensated by time window. The time of action of the voltage vector that is not forcibly boosted is compressed proportionally so that the sum of the time of action of all voltage vectors is equal to the switching cycle, and the final time of action is obtained. A pulse width modulation pulse is generated based on the security vector sequence and the final action time, and then sent to the driving circuit.

2. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 1, characterized in that, Obtain the original vector sequence and its corresponding original action time, including: A multi-vector control algorithm is run to obtain the set of voltage vectors to be used in the current control cycle. The set of voltage vectors includes at least two voltage vectors, each corresponding to a set of three-phase switch states. Obtain the action time corresponding to each voltage vector in the voltage vector set, wherein the sum of each action time is equal to the switching cycle, and the arrangement order of each voltage vector in the voltage vector set constitutes the original vector sequence.

3. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 1, characterized in that, The original vector sequence is reordered based on Hamming distance constraints to obtain a reordered safe vector sequence, including: Extract all non-repeating voltage vectors from the original vector sequence to form a candidate vector set; Using the voltage vectors in the candidate vector set as nodes and the Hamming distance between any two voltage vectors as edge weights, the shortest path through all nodes is solved to obtain the sequence with the minimum sum of Hamming distances between adjacent nodes, which is used as the initial safe sequence. Determine whether there are adjacent voltage vector pairs with a Hamming distance greater than 1 in the initial safety sequence. If so, insert an intermediate vector between the adjacent voltage vector pairs with a Hamming distance greater than 1, so that the Hamming distance between all adjacent voltage vectors in the inserted sequence is not greater than 1, and obtain the safety vector sequence. The duration of the inserted intermediate vector is assigned to a preset value, and the corresponding time is subtracted from the duration of the original two adjacent voltage vectors, so that the sum of the durations of all voltage vectors is equal to the switching cycle.

4. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 3, characterized in that, After inserting an intermediate vector between adjacent voltage vector pairs with a Hamming distance greater than 1, the method further includes: proportionally subtracting the duration of the intermediate vector from the duration of the original two adjacent voltage vectors, and after the subtraction, maintaining an equal reduction in the remaining duration of the original two adjacent voltage vectors, so that the volt-second integral vector sum of the original two adjacent voltage vectors before and after inserting the intermediate vector remains unchanged in space.

5. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 4, characterized in that, The intermediate vector is selected from the following two types of vectors: a zero vector in which all three-phase switch states are 0, or a transition vector in which the Hamming distance to the two adjacent voltage vectors is 1.

6. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 1, characterized in that, For each voltage vector in the safety vector sequence, the time-subtracted duration of the applied action time is subjected to a threshold check. The time-subtracted durations of applied action times that are less than the minimum safe pulse width threshold are forcibly increased to the minimum safe pulse width threshold to obtain the stretched duration, including: A preset minimum safe pulse width threshold is provided, wherein the minimum safe pulse width threshold is greater than or equal to the minimum reliable turn-on pulse width of the power switch. Iterate through each voltage vector in the safety vector sequence and obtain the action time corresponding to the voltage vector after time subtraction; If the time-deducted duration is greater than or equal to the minimum safe pulse width threshold, then the stretched duration of the voltage vector is set to be equal to the time-deducted duration. If the duration of action after time deduction is less than the minimum safe pulse width threshold, then the duration of action after stretching the voltage vector is set to be equal to the minimum safe pulse width threshold.

7. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 1, characterized in that, The applied time after stretching is compensated by a time window. The applied time of the voltage vectors not forcibly boosted is proportionally compressed so that the sum of the applied times of all voltage vectors equals the switching cycle, thus obtaining the final applied time. This includes: Calculate the sum of the duration increments of all forced boosted voltage vectors, where the duration increment is the difference between the minimum safe pulse width threshold and the duration after time subtraction. The sum of the effective times of all voltage vectors that were not forcibly boosted, after time subtraction, is obtained as the total compressible time. If the total compressible time is greater than zero, then a compression ratio factor is calculated. The compression ratio factor is equal to the ratio of the total compressible time minus the sum of the action time increments to the total compressible time. The final duration of each voltage vector that is not forcibly boosted is set as the compression factor multiplied by the duration of the voltage vector after time subtraction. The final duration of action of each voltage vector that will be forcibly boosted is set as the minimum safe pulse width threshold.

8. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 7, characterized in that, Also includes: If the total compressible time is equal to zero, then the final action time of all voltage vectors in the safety vector sequence is scaled proportionally so that the sum of the final action times of all voltage vectors is equal to the switching period.

9. The multi-vector control method for a three-level inverter based on sector reconstruction as described in claim 1, characterized in that, Based on the security vector sequence and the final action time, a pulse width modulation pulse is generated and sent to the driving circuit, including: The three-phase switching state of each voltage vector in the security vector sequence is converted into a comparison value for the corresponding phase; The duration of each voltage vector is determined based on the final action time; Write the comparison value and the duration into the comparison register of the pulse width modulation peripheral; The drive pulse is generated by the pulse width modulation peripheral to control the turn-on and turn-off of the power switch.

10. A multi-vector control system for a three-level inverter based on sector reconfiguration, characterized in that, The system is used to implement the multi-vector control method for a three-level inverter based on sector reconfiguration as described in any one of claims 1-9, including: The raw information acquisition module is used to acquire the raw vector sequence and its corresponding raw action time; The vector sequence rearrangement module is used to rearrange the original vector sequence based on the Hamming distance constraint to obtain the rearranged safe vector sequence. The Hamming distance is the number of phases with different states in the three-phase switching states of any two voltage vectors. The Hamming distance constraint requires that the Hamming distance between any two adjacent voltage vectors in the safe vector sequence is not greater than 1. The action time stretching module is used to perform threshold verification on the action time of each voltage vector in the safety vector sequence after time subtraction, and to forcibly increase the action time after time subtraction that is less than the minimum safety pulse width threshold to the minimum safety pulse width threshold, so as to obtain the stretched action time. The action time compensation module is used to perform time window compensation on the action time after stretching. By proportionally compressing the action time of the voltage vector that was not forcibly boosted, the sum of the action times of all voltage vectors is made equal to the switching cycle, thus obtaining the final action time. The modulation pulse generation module is used to generate a pulse width modulation pulse based on the security vector sequence and the final action time, and send it to the driving circuit.

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