CN-122000997-A - Control method and device for grid-formed energy storage converter and related products

CN122000997ACN 122000997 ACN122000997 ACN 122000997ACN-122000997-A

Abstract

The application relates to the technical field of power systems and discloses a control method and device of a grid-built energy storage converter and related products; the method comprises the steps of constructing a corresponding MPC (MPC) controller based on a pre-constructed discrete state space equation of the to-be-controlled grid-built energy storage converter, wherein the MPC controller comprises a cost function and constraint conditions, the cost function comprises a state error item, a preset optimization algorithm is adopted to conduct optimization solution on the MPC controller to obtain an active power reference value and a reactive power reference value when the cost function reaches the minimum, and a virtual synchronous generator module and a voltage-current double closed-loop control module are utilized to generate a pulse width modulation signal based on the active power reference value and the reactive power reference value so as to control the target grid-built energy storage converter. The application can effectively solve the problems of current impact, power angle instability and the like which are easy to occur in the grid-structured energy storage converter when the voltage drops, and ensures the stable grid-connected operation of the grid-structured energy storage converter under the power grid voltage drop working condition.

Inventors

LIU YINGMING
DING SHUO
WANG XIAODONG
WANG YINGWEI

Assignees

沈阳工业大学

Dates

Publication Date: 20260508
Application Date: 20260306

Claims (10)

1. The method for controlling the network-structured energy storage converter is characterized by comprising the following steps of: constructing a corresponding MPC controller based on a pre-constructed discrete state space equation of the to-be-controlled grid-formed energy storage converter, wherein the MPC controller comprises a cost function and constraint conditions, and the cost function comprises a state error item; Carrying out optimization solution on the MPC controller by adopting a preset optimization algorithm to obtain an active power reference value and a reactive power reference value when the cost function reaches the minimum; And generating a pulse width modulation signal based on the active power reference value and the reactive power reference value by using a virtual synchronous generator module and a voltage-current double closed-loop control module so as to control the target grid-structured energy storage converter.
2. The method for controlling a grid-formed energy storage converter according to claim 1, wherein the discrete state space equation of the grid-formed energy storage converter to be controlled is: Wherein, the Representing the system state vector at the k +1 sampling period, Representing the system state vector at the kth sampling period, Representing the control input vector at the kth sampling period, Including at the kth sampling period 、、 , , The operation power angle of the system is represented, Representing the angular frequency of the power grid, The output angular frequency of the to-be-controlled grid-type energy storage converter is represented, Representing the output voltage of the grid-type energy storage converter to be controlled, Including at the kth period And , , , Which represents the value of the active reference, The reactive power reference value is indicated and, , , , , Representing the identity matrix of the cell, The preset control period is indicated to be a preset control period, Representing the virtual damping coefficient of the damping device, Representing the rated angular frequency of the electrical network, Representing the frequency droop coefficient, Representing a virtual moment of inertia of the device, Representing the reactive-voltage sag factor, Represents the rated capacity reference of the grid-type energy storage converter, Indicating the nominal reference voltage.
3. The method for controlling a grid-formed energy storage converter according to claim 2, wherein the discrete state space equation of the grid-formed energy storage converter to be controlled is: Wherein, the Representing the total perturbation term at the kth sampling period, Including frequency-dependent perturbations at the kth sampling period Disturbance related to voltage Wherein , , Representing the actual active power output by the to-be-controlled grid-formed energy storage converter to the power grid through electromagnetic coupling, Representing the actual reactive power output by the to-be-controlled grid-formed energy storage converter to the power grid, Representing the rated output voltage of the to-be-controlled grid-type energy storage converter, , 。
4. The method for controlling a grid-formed energy storage converter according to claim 2, wherein the cost function further includes a control increment term, and the cost function is: where N represents the prediction time domain, A system state vector reference signal representing time k + j, The matrix is weighted for the state error and, A system state error vector at time k + j predicted for time k, In order to control the incremental weighting array, A control increment vector at time k+j, which represents the prediction at time k.
5. The method of claim 2, wherein the cost function further comprises an end state error term, and wherein the cost function is: where N represents the prediction time domain, A system state vector reference signal representing time k + j, The matrix is weighted for the state error and, A system state error vector at time k + j, predicted at time k, P being the end weight, Representing the system state error vector predicted at time k versus time k + N at the end of the prediction horizon.
6. The method of claim 2, wherein the cost function further comprises a control increment term and an end state error term, and the cost function is: where N represents the prediction time domain, A system state vector reference signal representing time k + j, The matrix is weighted for the state error and, A system state error vector at time k + j predicted for time k, In order to control the incremental weighting array, An optimal control increment vector representing the time k versus the time k + j, P being the end weight, Representing the system state error vector predicted at time k versus time k + N at the end of the prediction horizon.
7. The method of any one of claims 1-6, wherein the constraints include an initial state error constraint, a control increment vector constraint, and a weight matrix constraint.
8. A grid-formation energy storage converter control device, the device comprising: the model construction module is used for constructing a corresponding MPC controller based on a pre-constructed discrete state space equation of the to-be-controlled grid-constructed energy storage converter, wherein the MPC controller comprises a cost function and constraint conditions; the optimization module is used for carrying out optimization solution on the MPC controller by adopting a preset optimization algorithm to obtain an active power reference value and a reactive power reference value when the cost function reaches the minimum; And the control module is used for generating a pulse width modulation signal based on the active power reference value and the reactive power reference value by utilizing the virtual synchronous generator module and the voltage-current double closed-loop control module so as to control the target grid-structured energy storage converter.
9. An electronic device, comprising: processor, and A memory arranged to store computer executable instructions which, when executed, cause the processor to perform the steps of the grid formation energy storage converter control method of any one of claims 1 to 7.
10. A computer readable storage medium storing one or more programs, which when executed by an electronic device comprising a plurality of application programs, cause the electronic device to perform the steps of the grid-formed energy storage converter control method of any of claims 1-7.

Description

Control method and device for grid-formed energy storage converter and related products Technical Field The application relates to the technical field of power systems, in particular to a control method and device of a grid-built energy storage converter and related products. Background The Grid-built energy storage converter (Grid-Forming Converter, GFM) is a device integrating the functions of energy storage units and power electronic conversion, can autonomously build and maintain the voltage amplitude, frequency and phase of a power Grid, can independently support the power Grid to operate in a power Grid scene, and can realize the charge and discharge power adjustment of an energy storage system. With large-scale access of new energy sources (such as wind power and photovoltaic) to a power grid, the proportion of the traditional synchronous generator is gradually reduced, the inertia and damping of a power system are obviously reduced, and the power grid is more prone to frequency fluctuation, power angle instability and other problems when being subjected to disturbance such as voltage drop and short circuit fault. Therefore, the grid-structured energy storage converter with the virtual synchronization characteristic is a key device for improving the stability of the power grid, and the related technology of the grid-structured energy storage converter has become an important research direction in the field of power systems. When the voltage of the power grid drops, the energy storage converter needs to be controlled to have certain low voltage ride through capability, namely, grid-connected operation can be kept during the voltage sag, and the voltage recovery of the power grid is supported. At present, the existing energy storage converter control method comprises a fixed power control method, a VSG control method and the like, however, the existing method is easy to have the problems of current impact, power angle instability and the like when voltage drops, and the safe operation of a system is affected. Therefore, there is a need to solve this technical problem. Disclosure of Invention In view of the above, the embodiments of the present application provide a method, an apparatus, and a related product for controlling a grid-formation energy storage converter, which aim to solve the above-mentioned problems or at least partially solve the above-mentioned problems. In a first aspect, an embodiment of the present application provides a method for controlling a grid-formation energy storage converter, where the method includes: constructing a corresponding MPC controller based on a pre-constructed discrete state space equation of the to-be-controlled grid-formed energy storage converter, wherein the MPC controller comprises a cost function and constraint conditions, and the cost function comprises a state error item; Carrying out optimization solution on the MPC controller by adopting a preset optimization algorithm to obtain an active power reference value and a reactive power reference value when the cost function reaches the minimum; And generating a pulse width modulation signal based on the active power reference value and the reactive power reference value by using a virtual synchronous generator module and a voltage-current double closed-loop control module so as to control the target grid-structured energy storage converter. In a second aspect, an embodiment of the present application further provides a control device for a grid-formation energy storage converter, where the device includes: the model construction module is used for constructing a corresponding MPC controller based on a pre-constructed discrete state space equation of the to-be-controlled grid-constructed energy storage converter, wherein the MPC controller comprises a cost function and constraint conditions; the optimization module is used for carrying out optimization solution on the MPC controller by adopting a preset optimization algorithm to obtain an active power reference value and a reactive power reference value when the cost function reaches the minimum; And the control module is used for generating a pulse width modulation signal based on the active power reference value and the reactive power reference value by utilizing the virtual synchronous generator module and the voltage-current double closed-loop control module so as to control the target grid-structured energy storage converter. In a third aspect, embodiments of the present application also provide an electronic device comprising a processor and a memory arranged to store computer executable instructions which, when executed, cause the processor to perform the steps of the above-described grid-tied energy storage converter control method. In a fourth aspect, embodiments of the present application further provide a computer-readable storage medium storing one or more programs that, when executed by an electronic device including a plurality of application p