CN-115313951-B - Model predictive current control method, apparatus, computer device, and storage medium

CN115313951BCN 115313951 BCN115313951 BCN 115313951BCN-115313951-B

Abstract

The application relates to a model predictive current control method, a model predictive current control device, a computer device and a storage medium. The method comprises the steps of determining a target voltage vector group in a substrate voltage vector group by using a cost function in a sampling period, wherein the target voltage vector group comprises three different target voltage vectors, namely, the number of model predictive current control output vectors is three, compared with a single vector or a double vector, the coverage area of alternative voltage vectors corresponding to the three vectors is bigger, and the current ripple is smaller, so that the action duration corresponding to the three target voltage vectors is determined, and the expected voltage vector generated by combining the three target voltage vectors with smaller current ripple and the corresponding action duration is utilized, so that the current pulsation of an orthogonal axis is effectively reduced, and the inverter has good control performance and dynamic characteristics.

Inventors

ZHENG WENSHUAI
SUN LEI
Xia Lemei

Assignees

珠海格力电器股份有限公司

Dates

Publication Date: 20260508
Application Date: 20220824

Claims (8)

1. A model predictive current control method, the method comprising: Determining a target voltage vector group in a basic voltage vector group based on a cost function in a sampling period, wherein the basic voltage vector group comprises the target voltage vector group, the target voltage vector group comprises three different target voltage vectors, and the target voltage vector is any one basic voltage vector in the basic voltage vector group; Determining the corresponding action duration of each target voltage vector; Combining to form a desired voltage vector for controlling the inverter based on each target voltage vector and corresponding duration of action; based on each of the target voltage vectors and the corresponding duration of action, the method further includes, prior to combining to form a desired voltage vector for controlling the inverter: determining a matching state between the action duration corresponding to each target voltage vector and a preset duration condition; Under the condition that the matching state between the action duration corresponding to at least one target voltage vector and the preset duration condition is failed in matching, determining the reassignment action duration corresponding to each target voltage vector based on the sampling duration corresponding to the sampling period; the step of combining the reassigned duration of action as the duration of action to form a desired voltage vector for controlling the inverter based on each of the target voltage vectors and the corresponding duration of action; The three target voltage vectors are a first target voltage vector, a second target voltage vector and a third target voltage vector respectively, and when a matching state between an action duration corresponding to at least one target voltage vector and a preset duration condition is a matching failure, determining a reassignment action duration corresponding to each target voltage vector based on a sampling duration corresponding to the sampling period, wherein the reassignment action duration comprises at least one of the following steps: Under the condition that the matching of the action duration of the first target voltage vector and the preset duration fails, the reassignment action duration corresponding to the first target voltage vector is assigned to zero, and the difference value between the sampling duration and the action duration of the second target voltage vector is taken as the reassignment action duration corresponding to the third target voltage vector, wherein the reassignment action duration corresponding to the second target voltage vector is equal to the action duration of the second target voltage vector; Under the condition that the matching of the action duration of the second target voltage vector and the preset duration condition fails, the reassignment action duration corresponding to the second target voltage vector is assigned to zero, and the difference value between the sampling duration and the action duration of the first target voltage vector is taken as the reassignment action duration corresponding to the third target voltage vector, wherein the reassignment action duration corresponding to the first target voltage vector is equal to the action duration of the first target voltage vector; Under the condition that the matching of the action duration of the third target voltage vector and the preset duration fails, the reassignment action duration corresponding to the third target voltage vector is assigned to zero, and the sampling duration is divided into reassignment action duration corresponding to the first target voltage vector and reassignment action duration corresponding to the second target voltage vector according to the proportional relation between the action duration of the first target voltage vector and the action duration of the second target voltage vector; And under the condition that the action duration of the first target voltage vector and the action duration of the second target voltage vector are failed to be matched with the preset duration conditions, the reassignment action duration corresponding to the first target voltage vector and the reassignment action duration corresponding to the second target voltage vector are both assigned to be zero, and the sampling duration is taken as the reassignment action duration corresponding to the third target voltage vector.
2. The method of claim 1, wherein determining the set of target voltage vectors from the set of base voltage vectors based on the cost function comprises: Determining a first target voltage vector from a plurality of effective voltage vectors within the set of base voltage vectors based on the cost function, wherein the base voltage vector is an effective voltage vector or a zero vector; determining a second target voltage vector in a candidate voltage vector group based on the cost function, wherein the candidate voltage vector group comprises all effective voltage vectors except the first target voltage vector in the basic voltage vector group; and taking zero vectors in the first target voltage vector, the second target voltage vector and the basic voltage vector group as three target voltage vectors in the target voltage vector group.
3. The method of claim 2, wherein the determining a first target voltage vector from a plurality of effective voltage vectors within the set of base voltage vectors based on the cost function comprises: according to the current acquisition current obtained from the inverter, determining the prediction current corresponding to each effective voltage vector in the basic voltage vector group; determining a function value corresponding to each predicted current based on the cost function; And taking the effective voltage vector corresponding to the function value with the minimum value as the first target voltage vector.
4. The method of claim 1, wherein determining the duration of action for each of the target voltage vectors comprises: determining the current slope of each target voltage vector under the rotation coordinate axis; and determining the action duration corresponding to each target voltage vector according to the current slope corresponding to each target voltage vector and the sampling duration corresponding to the sampling period, wherein the sum of the action durations corresponding to each target voltage vector is the sampling duration.
5. The method of claim 1, wherein the method further comprises, prior to combining to form a desired voltage vector for controlling the inverter based on each of the target voltage vectors and the corresponding duration of action: determining a matching state between the action duration corresponding to each target voltage vector and a preset duration condition; And under the condition that the matching states between the action time length corresponding to each target voltage vector and the preset time length condition are successful, executing the step of combining the target voltage vectors and the corresponding action time lengths to form the expected voltage vector for controlling the inverter.
6. A model predictive current control apparatus, the apparatus comprising: a first determining module, configured to determine, in a sampling period, a target voltage vector group from a basic voltage vector group based on a cost function, where the basic voltage vector group includes the target voltage vector group, the target voltage vector group includes three different target voltage vectors, and the target voltage vector is any one basic voltage vector in the basic voltage vector group; The second determining module is used for determining the action duration corresponding to each target voltage vector; The voltage generation module is used for combining and forming a desired voltage vector for controlling the inverter based on each target voltage vector and corresponding acting duration; Based on each target voltage vector and the corresponding action duration, before combining to form a desired voltage vector for controlling the inverter, the method further comprises: determining a matching state between the action duration corresponding to each target voltage vector and a preset duration condition; Under the condition that the matching state between the action duration corresponding to at least one target voltage vector and the preset duration condition is failed in matching, determining the reassignment action duration corresponding to each target voltage vector based on the sampling duration corresponding to the sampling period; the step of combining the reassigned duration of action as the duration of action to form a desired voltage vector for controlling the inverter based on each of the target voltage vectors and the corresponding duration of action; The three target voltage vectors are a first target voltage vector, a second target voltage vector and a third target voltage vector respectively, and when a matching state between an action duration corresponding to at least one target voltage vector and a preset duration condition is a matching failure, determining a reassignment action duration corresponding to each target voltage vector based on a sampling duration corresponding to the sampling period, wherein the reassignment action duration comprises at least one of the following steps: Under the condition that the matching of the action duration of the first target voltage vector and the preset duration fails, the reassignment action duration corresponding to the first target voltage vector is assigned to zero, and the difference value between the sampling duration and the action duration of the second target voltage vector is taken as the reassignment action duration corresponding to the third target voltage vector, wherein the reassignment action duration corresponding to the second target voltage vector is equal to the action duration of the second target voltage vector; Under the condition that the matching of the action duration of the second target voltage vector and the preset duration condition fails, the reassignment action duration corresponding to the second target voltage vector is assigned to zero, and the difference value between the sampling duration and the action duration of the first target voltage vector is taken as the reassignment action duration corresponding to the third target voltage vector, wherein the reassignment action duration corresponding to the first target voltage vector is equal to the action duration of the first target voltage vector; Under the condition that the matching of the action duration of the third target voltage vector and the preset duration fails, the reassignment action duration corresponding to the third target voltage vector is assigned to zero, and the sampling duration is divided into reassignment action duration corresponding to the first target voltage vector and reassignment action duration corresponding to the second target voltage vector according to the proportional relation between the action duration of the first target voltage vector and the action duration of the second target voltage vector; And under the condition that the action duration of the first target voltage vector and the action duration of the second target voltage vector are failed to be matched with the preset duration conditions, the reassignment action duration corresponding to the first target voltage vector and the reassignment action duration corresponding to the second target voltage vector are both assigned to be zero, and the sampling duration is taken as the reassignment action duration corresponding to the third target voltage vector.
7. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the steps of the method according to any one of claims 1 to 5 when the computer program is executed by the processor.
8. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method according to any one of claims 1 to 5.

Description

Model predictive current control method, apparatus, computer device, and storage medium Technical Field The present application relates to the field of power electronics technologies, and in particular, to a model prediction current control method, a device, a computer device, and a storage medium. Background The model predictive current control (model predictive current control, MPCC) has the characteristics of quick dynamic response, simple control mode and the like. Compared with PWM control, MPCC is more flexible and accurate in control of an inverter switching tube in a sampling period, the output current state of the inverter is predicted, the predicted value is brought into a cost function to select an optimal voltage vector, and the optimal voltage vector is utilized to synthesize expected voltage to control the inverter. However, the number of vectors sent by the MPCC in one sampling period is usually single vector or double vector, and no matter whether the number of vectors sent by the MPCC in one sampling period is single vector or double vector, the coverage area of the alternative voltage vector is smaller, the current ripple is larger, and the control performance of the synthesized expected voltage on the inverter is poor. Disclosure of Invention In order to solve the technical problem that the expected voltage generated based on the existing MPCC is poor in inverter control performance, the application provides a model predictive current control method, a model predictive current control device, computer equipment and a storage medium. In a first aspect, the present application provides a model predictive current control method, including: Determining a target voltage vector group in a basic voltage vector group based on a cost function in a sampling period, wherein the basic voltage vector group comprises the target voltage vector group, the target voltage vector group comprises three different target voltage vectors, and the target voltage vector is any one basic voltage vector in the basic voltage vector group; Determining the corresponding action duration of each target voltage vector; Based on the target voltage vectors and the corresponding duration of action, desired voltage vectors for controlling the inverter are formed in a combined manner. In a second aspect, the present application provides a model predictive current control apparatus comprising: a first determining module, configured to determine, in a sampling period, a target voltage vector group from a basic voltage vector group based on a cost function, where the basic voltage vector group includes the target voltage vector group, the target voltage vector group includes three different target voltage vectors, and the target voltage vector is any one basic voltage vector in the basic voltage vector group; The second determining module is used for determining the action duration corresponding to each target voltage vector; and the voltage generation module is used for combining and forming a desired voltage vector for controlling the inverter based on each target voltage vector and the corresponding acting duration. In a third aspect, the present application provides a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the following steps when executing the computer program: Determining a target voltage vector group in a basic voltage vector group based on a cost function in a sampling period, wherein the basic voltage vector group comprises the target voltage vector group, the target voltage vector group comprises three different target voltage vectors, and the target voltage vector is any one basic voltage vector in the basic voltage vector group; Determining the corresponding action duration of each target voltage vector; Based on the target voltage vectors and the corresponding duration of action, desired voltage vectors for controlling the inverter are formed in a combined manner. In a fourth aspect, the present application provides a computer readable storage medium having stored thereon a computer program which when executed by a processor performs the steps of: Determining a target voltage vector group in a basic voltage vector group based on a cost function in a sampling period, wherein the basic voltage vector group comprises the target voltage vector group, the target voltage vector group comprises three different target voltage vectors, and the target voltage vector is any one basic voltage vector in the basic voltage vector group; Determining the corresponding action duration of each target voltage vector; Based on the target voltage vectors and the corresponding duration of action, desired voltage vectors for controlling the inverter are formed in a combined manner. Based on the model predictive current control method, in each sampling period, a target voltage vector group is determined in a substrate voltage ve