Control method and device based on current type rectifier, electronic equipment and medium

Abstract

The invention discloses a control method and device based on a current type rectifier, electronic equipment and a medium, and the method comprises the steps: obtaining the network side voltage, network side current and AC side capacitor voltage data of the current type rectifier at a first moment, and calculating the input current data at the first moment, the input current data is determined according to the switching state of a rectifier bridge in the current type rectifier at the previous moment; inputting the sampling data and the current data into a pre-established prediction model to predict a state variable, calculating a grid-side input current based on the state variable and the input current corresponding to different switching states, calculating a grid-side reference current at the direct current side of the current type rectifier by adopting proportional-integral control based on an instantaneous power theory, and calculating the grid-side reference current according to the grid-side reference current. The cost model is established based on the grid-side reference current and the grid-side input current, and the switch state corresponding to the minimum value is calculated by the cost model to control the rectification output of the current type rectifier at the target moment, so that the rectification output is well controlled, and the output ripple is small and the quality is high.

Description

Technical Field

[0001] The present application relates to the technical field of rectifier control, and in particular to a control method, device, electronic device and storage medium based on a current-type rectifier. Background Art

[0002] Buck rectifier is also called current source rectifier (CSR). It can be widely used in superconducting energy storage, electric vehicle charging piles, high-power motor drives, large hydropower plant DC systems and other occasions due to its wide range of DC step-down output capability, high short-circuit protection reliability, fast dynamic response speed, four-quadrant operation and regenerative braking.

[0003] In related technologies, in order to suppress the CSR DC output ripple, a capacitor is often connected in parallel on its output side to form an LC second-order filter circuit with its DC output inductor to smooth the output current. However, as the order of the mathematical model increases, traditional control requires decoupling of the model, making the control process complex and the effect mediocre. Summary of the invention

[0004] In view of the above problems, the present application provides a control method, device, electronic device and storage medium based on a current-source rectifier to at least solve the problems existing in the related art.

[0005] In a first aspect, an embodiment of the present application provides a control method based on a current-source rectifier, comprising:

[0006] Acquire sampling data of the current-source rectifier at a first moment, and calculate input current data of the current-source rectifier at the first moment, wherein the input current data is determined according to the switch state of the rectifier bridge in the current-source rectifier at a previous moment; the sampling data includes grid-side voltage, grid-side current and AC capacitor voltage data;

[0007] Inputting the sampled data and input current data into a pre-established prediction model to predict the state variables of the sampled data at a target time;

[0008] Calculating the grid-side input current based on the state variable and the input current corresponding to different switch states;

[0009] Based on the instantaneous power theory, proportional-integral control is used on the DC side of the current source rectifier to calculate the grid-side reference current;

[0010] A cost model is established based on the grid-side reference current and the grid-side input current, and the switching state corresponding to the minimum value calculated by the cost model is used to control the rectification output of the current-source rectifier at the target time.

[0011] In some embodiments, the control method of the current source rectifier further includes:

[0012] Acquire the grid-side current and the AC-side capacitor voltage of the current-source rectifier as state variables, and acquire the grid voltage and the current input to the current-source rectifier as control variables;

[0013] Constructing a state space equation in continuous time based on the state variables and control variables;

[0014] The state space equation is discretized to obtain the prediction model.

[0015] In some embodiments, the switch state corresponding to the minimum value calculated by the cost model controls the rectification output of the current source rectifier at the target time, including:

[0016] Determining a corresponding relationship between a switch state of the rectifier bridge and an input current of the current-source rectifier;

[0017] Traversing all the vector sequences of the switch states based on the state variable to determine the vector sequence value corresponding to the minimum value calculated by the cost model at the target moment;

[0018] The bridge arm of the rectifier bridge is controlled to be turned off based on the vector sequence value.

[0019] In some embodiments, the calculating the grid-side reference current by using proportional-integral control on the DC side of the current-source rectifier based on the instantaneous power theory includes:

[0020] Determining an active power reference value of the current source rectifier based on instantaneous power theory;

[0021] Based on the DC side of the current source rectifier, a proportional-integral calculation formula is used to control the given active power reference value to calculate the grid-side reference current.

[0022] In some embodiments, the prediction model is calculated using the following calculation formula, which includes:

[0023]

[0024] In the formula, i g(k+1) 、u c(k+1) is the state variable at the target time, i g(k) 、u c(k) 、v g(k) is the sampling data at the first moment, i i(k) is the current data, T ac is the sampling time of the state variables of the AC side of the current source rectifier, C ac is the capacitance value of the AC side of the current source rectifier, Lac is the inductance value of the AC side of the current type rectifier.

[0025] In some embodiments, the proportional integral calculation formula includes:

[0026]

[0027] In the formula, is the grid-side current reference value, P ref is the active power reference value, i gα_ref is the α-axis component of the grid-side current reference value in the two-phase stationary coordinate system, i gβ _ref is the β-axis component of the grid-side current reference value in the two-phase stationary coordinate system, v gα is the α-axis component of the grid-side voltage value in the two-phase stationary coordinate system, v gβ is the β-axis component of the grid-side voltage value in the two-phase stationary coordinate system, and j is the rotation factor.

[0028] In some embodiments, the cost model is established based on the grid-side reference current and the grid-side input current, wherein the calculation formula of the cost model includes:

[0029]

[0030] In the formula, is the grid-side reference current, i g(k+2) is the grid-side input current.

[0031] In a second aspect, an embodiment of the present application provides a control device based on a current-source rectifier, comprising:

[0032] An acquisition module, used to acquire sampling data of a current-source rectifier at a first moment, and calculate input current data of the current-source rectifier at the first moment, wherein the input current data is determined according to the switch state of a rectifier bridge in the current-source rectifier at a previous moment; the sampling data includes grid-side voltage, grid-side current and AC capacitor voltage data;

[0033] A prediction module, used for inputting the sampled data and current data into a pre-established prediction model to predict the state variables of the sampled data at a target time;

[0034] A first calculation module, configured to calculate a grid-side input current based on the state variable and input currents corresponding to different switch states;

[0035] A second calculation module is used to calculate the grid-side reference current by using proportional-integral control on the DC side of the current-source rectifier based on instantaneous power theory;

[0036] The control module is used to establish a cost model based on the grid-side reference current and the grid-side input current, and control the rectification output of the current-source rectifier at the target time using the switch state corresponding to the minimum value calculated by the cost model.

[0037] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory and a processor, wherein the memory stores program code that can be executed on the processor, and when the program code is executed by the processor, a control method based on a current-type rectifier as described in any implementation method of the first aspect is implemented.

[0038] In a fourth aspect, an embodiment of the present application provides a computer storage medium storing one or more programs, which can be executed by an electronic device as described in the third aspect to implement a control method based on a current-type rectifier as described in any implementation method of the first aspect.

[0039] The embodiments of the present application provide a control method, device, electronic device and storage medium based on a current-type rectifier. The control method of the current-type rectifier includes: obtaining sampling data of the current-type rectifier at a first moment, and calculating the input current data of the current-type rectifier at the first moment, wherein the input current data is determined according to the switch state of the rectifier bridge in the current-type rectifier at the previous moment; the sampling data includes grid-side voltage, grid-side current and AC capacitor voltage data; the sampling data and the current data are input into a pre-established prediction model to predict the state variables of the sampling data at a target moment; the grid-side input current is calculated based on the state variables and the input current corresponding to different switch states; the grid-side reference current is calculated by proportional-integral control on the DC side of the current-type rectifier based on the instantaneous power theory; a cost model is established based on the grid-side reference current and the grid-side input current, and the rectifier output of the current-type rectifier is controlled at the target moment with the switch state corresponding to the minimum value calculated by the cost model, so as to achieve better control of the rectifier output, so that the output ripple is small and the quality is high.

[0040] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Hereinafter, the present application will be described in more detail based on embodiments and with reference to the accompanying drawings.

[0042] Figure 1 A schematic flow chart of a control method based on a current source rectifier proposed in an embodiment of the present application is shown;

[0043] Figure 2An exemplary predictive control timing diagram proposed in an embodiment of the present application is shown;

[0044] Figure 3 A block diagram of a model predictive control principle based on a current source rectifier proposed in an embodiment of the present application is shown;

[0045] Figure 4 A steady-state simulation waveform diagram of a model predictive control based on a current-source rectifier proposed in an embodiment of the present application is shown;

[0046] Figure 5 A set of dynamic simulation waveform diagrams of a model predictive control based on a current source rectifier proposed in one embodiment of the present application is shown;

[0047] Figure 6 A schematic diagram of a current source rectifier topology structure proposed in an embodiment of the present application is shown;

[0048] Figure 7 A structural block diagram of a control device based on a current source rectifier proposed in an embodiment of the present application is shown;

[0049] Figure 8 A structural block diagram of an electronic device for executing a control method based on a current-source rectifier according to an embodiment of the present application is shown;

[0050] Fig. 9 A computer-readable storage medium for storing or carrying a control method based on a current-source rectifier according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0051] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0052] In the study of related technologies, the applicant found that in order to suppress the CSR (Current Source Rectifier, CSR) DC output ripple, a capacitor is often connected in parallel on its output side to form an LC second-order filter circuit with its DC output inductor to smooth the output current. However, as the order of the mathematical model increases, traditional control requires decoupling of the model, making the control process complex and the effect mediocre.

[0053] Based on this, the applicant has made comprehensive improvements to the modeling of the current-source rectifier in order to better control the rectifier output so that the DC output ripple is smaller and the quality is higher.

[0054] In view of the above problem, the applicant proposes a control method, device, electronic device and storage medium based on a current source rectifier provided in the embodiments of the present application, which will be described in detail in the subsequent embodiments.

[0055] The following is an introduction to the application scenario of the control method based on the current source rectifier provided in the embodiment of the present application:

[0056] See also Figure 6 , Figure 6 A schematic diagram of a current-source rectifier topology structure provided in an embodiment of the present application.

[0057] exist Figure 6 In the above example, the AC side inductance L is ignored. ac The parasitic resistance and the equivalent resistance of the transmission line, v g is a three-phase AC voltage source; the AC side inductance L ac and capacitor C ac Together they form a second-order filter circuit to attenuate the CSR grid-side current i g The high-order harmonics in the rectifier bridge can be a structure of 6 series diodes, and the large inductor L on the DC side dc Suppress output current ripple and smooth output current i o .

[0058] To achieve PWM control of CSR, at any time, in the structure of 6 series rectifier bridge diodes, only one switch corresponding to the upper bridge arm (S1, S3, S5) and the lower bridge arm (S4, S6, S2) is turned on. Therefore, CSR has 9 switching states. The CSR switching state is defined as S = [S1 S3 S5 S4 S6 S2], where S1~S6 are 1 or 0 (on or off). Different switching states S and input current i iαβ The corresponding relationship is shown in Table 1. The corresponding input current i of different switch states iαβ As shown below:

[0059]

[0060] Table 1

[0061] See also Figure 1 , Figure 1 FIG. 1 is a flow chart of a control method based on a current-source rectifier provided in an embodiment of the present application. In this embodiment, the control method based on the current-source rectifier can be applied to Figure 7 The control device 300 based on the current source rectifier is shown in FIG. Figure 8In the electronic device 200 shown, the electronic device may include one or more electronic devices, and information may be transmitted between the multiple electronic devices in a wireless and / or wired manner. The multiple electronic devices may collaborate to complete the control method based on the current source rectifier. For example, the electronic device may include a mobile terminal, a computer, a tablet, etc., which is not limited in this application. Figure 1 The process shown is described in detail, and the control method based on the current-source rectifier may include S110 to S150.

[0062] S110: Acquire sampling data of the current-source rectifier at the first moment, and calculate input current data of the current-source rectifier at the first moment, wherein the input current data is determined according to the switching state of the rectifier bridge in the current-source rectifier at the previous moment; the sampling data includes grid-side voltage, grid-side current and AC capacitor voltage data.

[0063] In the embodiment of the present application, sampling data can be obtained by sensor measurement, wherein the sampling data can be collected at the first moment (moment k) including: g(k) 、i g(k) and u c(k) , which respectively represent: the grid voltage at time k, the CSR grid-side current at time k and the AC-side capacitor voltage at time k. The input current i at the current moment (time k) is determined by calculating the switch state of the rectifier bridge in the current-source rectifier at the previous moment (time k-1). i(k) .

[0064] In some embodiments, the control method based on the current-source rectifier may further include S101 to S103 .

[0065] S101: Acquire the grid-side current of the current-source rectifier and the AC-side capacitor voltage as state variables, and acquire the grid voltage and the current of the input current-source rectifier as control variables.

[0066] In the embodiment of the present application, the CSR grid-side current i g and the AC side capacitor voltage u c As state variables, the control variables are grid voltage v g and the input rectifier current i i .

[0067] S102: Constructing a state space equation in continuous time based on the state variables and the control variables.

[0068] In the embodiment of the present application, the expression of the state space equation is as follows:

[0069]

[0070] In the formula, the control quantity i of the state space equation isi Determined by different switch states, C ac is the capacitance value of the AC side of the current source rectifier, L ac is the inductance value of the AC side of the current type rectifier.

[0071] In the embodiment of the present application, the CSR model predicts and controls the basic current state variables to establish a cost function to traverse all switch vector sequences, find the switch vector that minimizes the state quantity deviation at the next moment, and outputs control rectification.

[0072] S103: Discretize the state space equation to obtain a prediction model.

[0073] In the embodiment of the present application, in order to predict the state variables at the next moment, the state space equation is discretized.

[0074] It should be noted that, usually when the sampling frequency is high, that is, Ts ≥ 10kHz, the forward Euler discretization method has a relatively high accuracy. However, due to the existence of a second-order LC filter circuit on the AC side of the CSR topology, the forward Euler discretization has certain limitations, and the prediction model needs to be corrected to obtain the prediction model.

[0075] S120: Input the sampled data and the input current data into a pre-established prediction model to predict the state variables of the sampled data at the target time.

[0076] In the embodiment of the present application, the prediction model is calculated using the following calculation formula, which includes:

[0077]

[0078] In the formula, i g(k+1) 、u c(k+1) is the state variable at the target time, i g(k) 、u c(k) 、v g(k) is the sampling data at the first moment, i i(k) is the current data, T ac is the sampling time of the state variables of the AC side of the current source rectifier, C ac is the capacitance value of the AC side of the current source rectifier, L ac is the inductance value of the AC side of the current type rectifier.

[0079] It should be noted that the time sequence is that the target moment is greater than the first moment.

[0080] Among them, considering that due to the high sampling frequency, the performance of MPC will be affected by the delay caused by the calculation time. Figure 2 , Figure 2An exemplary predictive control timing diagram provided in the embodiment of the present application can realize delay compensation of model predictive control by adopting a two-step method. The two-step predictive control calculates the cost function of two sampling cycles in advance, the first cycle is used for control delay compensation, and the second cycle is used for optimization algorithm.

[0081] The target moment is predicted by the prediction model, that is, the state variable i at the next moment (k+1 moment) g(k+1) and u c(k+1) .

[0082] It should be noted that due to the short sampling time, it can be approximately considered that v g(k+1) ≈v g(k) .

[0083] S130: Calculating the grid-side input current based on the state variables and the input currents corresponding to different switch states.

[0084] In the embodiment of the present application, the input current i corresponding to the 9 different switch states in Table 1 can be i , calculate 9 corresponding grid-side input currents i g(k+2) , where CSR control achieves good rectification while making the grid-side current sinusoidal.

[0085] S140: Based on the instantaneous power theory, proportional-integral control is used on the DC side of the current source rectifier to calculate the grid-side reference current.

[0086] Among them, proportional integral control can be achieved through a PI regulator.

[0087] In some embodiments, S140 also includes S141 to S142.

[0088] S141: Determine an active power reference value of the current source rectifier based on instantaneous power theory.

[0089] In the embodiment of the present application, according to the instantaneous power theory, the CSR active power reference value P * and reactive power reference value Q * It can be expressed as:

[0090]

[0091] In the formula, i gα_ref is the α-axis component of the grid-side current reference value in the two-phase stationary coordinate system, i gβ _ref is the β-axis component of the grid-side current reference value in the two-phase stationary coordinate system, v gα is the α-axis component of the grid-side voltage value in the two-phase stationary coordinate system, v gβ is the β-axis component of the grid-side voltage value in the two-phase stationary coordinate system, P ref is the active power reference value, Qref is the reactive power reference value.

[0092] S142: Based on the DC side of the current source rectifier, a proportional-integral calculation formula is used to control a given active power reference value to calculate a grid-side reference current.

[0093] In the embodiment of the present application, the active power reference P ref The reactive power reference Q can be set by the PI regulator of the DC side current, and the unity power factor operation ref Set to 0.

[0094] Then, the grid-side reference current (grid-side current reference value) is calculated by the proportional-integral calculation formula:

[0095]

[0096] In the formula, is the grid-side current reference value, P ref is the active power reference value, i gα_ref is the α-axis component of the grid-side current reference value in the two-phase stationary coordinate system, i gβ _ref is the β-axis component of the grid-side current reference value in the two-phase stationary coordinate system, v gα is the α-axis component of the grid-side voltage value in the two-phase stationary coordinate system, v gβ is the β-axis component of the grid-side voltage value in the two-phase stationary coordinate system, and j is the rotation factor.

[0097] S150: establishing a cost model based on the grid-side reference current and the grid-side input current, and controlling the rectification output of the current-source rectifier at a target time using a switch state corresponding to a minimum value calculated by the cost model.

[0098] The calculation formula of the cost model includes:

[0099]

[0100] In the formula, is the grid-side reference current, i g(k+2) is the grid-side input current.

[0101] In some embodiments, the switch state corresponding to the minimum value calculated by the cost model in step S150 controls the rectification output of the current source rectifier at the target time, including S151 to S153.

[0102] S151: Determine the corresponding relationship between the switch state of the rectifier bridge and the input current of the current-source rectifier.

[0103] S152: traverse the vector sequences of all switch states based on the state variables to determine the vector sequence value corresponding to the minimum value calculated by the cost model at the target moment.

[0104] In the embodiment of the present application, the proportional integral calculation formula is brought into the cost model, and the switch state corresponding to min(g) is found as the switch drive at the next moment, so that the grid-side current closely follows the reference value.

[0105] S153: Controlling the bridge arm of the rectifier bridge to shut down based on the vector sequence value.

[0106] In this embodiment, in the predictive control scheme, the CSR AC side adopts model predictive control based on two-step delay compensation, and the DC side adopts traditional PI control. The combination of the two can better control the rectifier output and the DC output ripple is small and the quality is high.

[0107] See also Figure 3 , Figure 3 A block diagram of the model predictive control principle of a current source rectifier provided in an embodiment of the present application. In the embodiment of the present application, after sampling the DC output current io, the reference value is tracked by PI control, and the grid-side reference current at time k+2 is calculated using the instantaneous power theory. The grid-side reference current at time k+2 and the predicted current establish a cost function, calculate the switch state corresponding to the minimum cost function, and apply the optimal switch state to the system at the current time (time k) to control the CSR rectifier output.

[0108] This application simulates and verifies the above control strategy, and the specific simulation parameters are shown in Table 2:

[0109]

[0110] Table 2

[0111] See also Figure 4 , Figure 4 A set of steady-state simulation waveform diagrams of a model predictive control based on a current-source rectifier provided in an embodiment of the present application.

[0112] In the attached figure, the upper left corner is the grid-side voltage v gA , grid-side current i gA The data graph shows that the voltage and current on the CSR grid side are in the same frequency and phase, and the grid side current is highly sinusoidal; the upper right corner is the DC output current i o The data graph shows that the CSR DC output current can stably track the reference value of 20A, with small current ripple and a vibration amplitude of about 0.5A; the lower left corner is a data graph of the total harmonic distortion rate of the grid-side current, which shows that after adding passive damping, the total harmonic distortion rate of the system grid-side current is 3.44%, which meets the standards of GB-T / 14549-1993 and IEEE519; the lower right corner is a data graph of the active power emitted by the grid and the active power absorbed by the load, which shows that there is a gap between the active power emitted by the CSR grid and the power absorbed by the load, and the overall conversion efficiency is about 91%, so adding passive damping will cause more power loss.

[0113] See also Figure 5 , Figure 5 This is a set of waveform diagrams of dynamic simulation of model predictive control based on a current-source rectifier proposed in one embodiment of the present application, wherein at 0.1s, the load from 100% to 50% is changed.

[0114] In the attached figure, the upper left corner shows that the CSR grid-side voltage and current are of the same frequency and phase, the grid-side current is highly sinusoidal, and the tracking effect is good; the upper right corner shows that the DC output effect is good, and the DC output current can track the reference value well before and after the load mutation, and is stable at 20A; the lower left corner shows that the grid-side power factor is good; the lower right corner shows that due to the reduction in load, the grid-side current decreases, and the power loss in the damping resistor becomes smaller.

[0115] In summary, this application establishes a prediction model by discrete processing of the state space equation of CSR. Considering the high sampling frequency of the system and the delay caused by the calculation time, a two-step method is used to predict the AC side current to achieve delay compensation. The DC side uses PI control and instantaneous power theory to calculate the AC side reference current, and uses the AC side reference current and predicted current to establish a cost function. Among the 9 switching states of CSR, the switching state corresponding to the minimum value of the cost function is used as the trigger pulse state to control the rectifier output.

[0116] See also Figure 7 , Figure 7 This is a structural block diagram of a control device based on a current source rectifier provided in the present application. The control device 300 based on a current source rectifier includes: an acquisition module 310, a prediction module 320, a first calculation module 330, a second calculation module 340 and a control module 350, wherein:

[0117] The acquisition module 310 is used to obtain the sampling data of the current-type rectifier at the first moment, and calculate the input current data of the current-type rectifier at the first moment, wherein the input current data is determined according to the switching state of the rectifier bridge in the current-type rectifier at the previous moment; the sampling data includes the grid-side voltage, the grid-side current and the AC capacitor voltage data.

[0118] The prediction module 320 is used to input the sampled data and the current data into a pre-established prediction model to predict the state variables of the sampled data at the target time.

[0119] The first calculation module 330 is used to calculate the grid-side input current based on the state variable and the input current corresponding to different switch states.

[0120] The second calculation module 340 is used to calculate the grid-side reference current by adopting proportional-integral control on the DC side of the current-source rectifier based on the instantaneous power theory.

[0121] The control module 350 is used to establish a cost model based on the grid-side reference current and the grid-side input current, and control the rectification output of the current-source rectifier at a target time using a switch state corresponding to a minimum value calculated by the cost model.

[0122] The device embodiment in the present application may also include other modules, which specifically correspond to part of the content of the above method.

[0123] It should be noted that the device embodiments in the present application correspond to each other with the aforementioned method embodiments. The specific principles in the device embodiments can be found in the contents of the aforementioned method embodiments and will not be repeated here.

[0124] In several embodiments provided in this embodiment, the coupling between modules may be electrical, mechanical or other forms of coupling.

[0125] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of software functional modules.

[0126] See also Figure 8 , Figure 8 The present application provides a structural block diagram of an electronic device 200 that can execute the above-mentioned control method based on a current-source rectifier. The electronic device 200 can be a smart phone, a tablet computer, a computer, a portable computer or other devices.

[0127] The electronic device 200 further includes a processor 202 and a memory 204. The memory 204 stores a program that can execute the contents of the aforementioned embodiments, and the processor 202 can execute the program stored in the memory 204.

[0128] Among them, the processor 202 may include one or more cores and message matrix units for processing data. The processor 202 uses various interfaces and lines to connect various parts of the entire electronic device 200, and executes various functions and processes data of the electronic device 200 by running or executing instructions, programs, code sets or instruction sets stored in the memory 204, and calling data stored in the memory 204. Optionally, the processor 202 can be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field programmable gate array (Field-Programmable Gate Array, FPGA), and programmable logic array (Programmable Logic Array, PLA). The processor 202 can integrate one or a combination of a central processing unit (Central Processing Unit, CPU), a graphics processing unit (Graphics Processing Unit, GPU) and a modulation decoder. Among them, the CPU mainly processes the operating system, user interface and application programs; the GPU is responsible for rendering and drawing display content; and the modem is used to process wireless communications. It can be understood that the above-mentioned modulation decoder may not be integrated into the processor, but may be implemented separately through a communication chip.

[0129] The memory 204 may include a random access memory (RAM) or a read-only memory (ROM). The memory 204 may be used to store instructions, programs, codes, code sets or instruction sets. The memory 204 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for implementing at least one function (e.g., instructions for a user to obtain a random number), instructions for implementing the following various method embodiments, etc. The data storage area may also store data (e.g., random numbers) created by the terminal during use, etc.

[0130] The electronic device 200 may also include a network module and a screen. The network module is used to receive and send electromagnetic waves, realize the mutual conversion between electromagnetic waves and electrical signals, and thus communicate with a communication network or other devices, such as communicating with an audio playback device. The network module may include various existing circuit components for performing these functions, such as antennas, radio frequency transceivers, digital signal processors, encryption / decryption chips, user identity modules (SIM) cards, memories, etc. The network module may communicate with various networks such as the Internet, corporate intranets, wireless networks, or communicate with other devices via wireless networks. The above-mentioned wireless networks may include cellular telephone networks, wireless local area networks, or metropolitan area networks. The screen may display interface content and perform data interaction.

[0131] Please refer to Fig. 9 , Fig. 9 The computer-readable storage medium 400 stores program code 410, which can be called by a processor to execute the method described in the above method embodiment.

[0132] The computer-readable storage medium 400 may be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM, a hard disk, or a ROM. Optionally, the computer-readable storage medium includes a non-transitory computer-readable storage medium. The computer-readable storage medium 400 has storage space for program codes 410 that perform any method steps in the above method. These program codes 410 can be read from or written to one or more computer program products. The program codes 410 can be compressed, for example, in an appropriate form.

[0133] The embodiment of the present application also provides a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. The processor of the computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the control method based on the current-source rectifier described in the above various optional implementations.

[0134] Exemplarily, the computer program product is a MATLAB simulation code, which is as follows:

[0135] function[S1,S2,S3,S4,S5,S6]=fcn(uL,iL,io,uia,uib,usa,usb,isa,isb)

[0136] Co=100e-6; / / CSR DC side capacitance parameters;

[0137] Lo=5e-3; / / CSR DC side inductance parameters;

[0138] Ci=12e-6; / / CSR AC side capacitance parameters;

[0139] Li=0.45e-3; / / CSR AC side inductance parameters;

[0140] uL1_ref=400; / / CSR load voltage reference value;

[0141] Tso=333e-6; / / CSR DC side sampling time;

[0142] Tsi=6.67e-6; / / CSR AC side sampling time;

[0143] io_ref=Co*(uL1_ref-uL) / Tso+iL; / / output current reference value at time k+1;

[0144] uo_ref=Lo*(io_ref-io) / Tso+uL; / / output voltage reference value at time k+1;

[0145] Psk2_ref=io_ref*uo_ref*0.958; / / active power prediction reference value at time k+2;us=usa+1j*usb;

[0146] ui=uia+1j*uib;

[0147] is=isa+1j*isb;

[0148] state1 = [1 0 0 0 0 1];

[0149] state2 = [0 1 0 0 0 1];

[0150] state3 = [0 1 0 1 0 0];

[0151] state4 = [0 0 1 1 0 0];

[0152] state5 = [0 0 1 0 1 0];

[0153] state6 = [1 0 0 0 1 0];

[0154] state7 = [1 0 0 1 0 0];

[0155] state8 = [0 1 0 0 1 0];

[0156] state9 = [0 0 1 0 0 1];

[0157] S = [state1; state2; state3; state4; state5; state6; state7; state8; state9]; / / 9 switch states;

[0158] ii1=(1+1j / sqrt(3))*io;

[0159] ii2=2*1j / sqrt(3)*io;

[0160] ii3 = (-1 + 1j / sqrt (3)) * io;

[0161] ii4 = -(1+1j / sqrt(3))*io;

[0162] ii5 = -2*1j / sqrt(3)*io;

[0163] ii6 = (1-1j / sqrt(3))*io;

[0164] ii7=0;

[0165] ii8=0;

[0166] ii9=0;

[0167] ii=[ii1 ii2 ii3 ii4 ii5 ii6 ii7 ii8 ii9];

[0168] / / 9 kinds of switch states corresponding to the input current;

[0169] persistent k_old

[0170] if isempty(k_old),k_old=1; end

[0171] is_k1=(1-Tsi^2 / (2*Ci*Li))*is-Tsi*ui / Li+Tsi*us / Li+Tsi^2*ii(k_old) / (2*Ci*Li);

[0172] / / CSR input current at time k+1;

[0173] ui_k1=Tsi*is / Ci+(1-Tsi^2 / (2*Ci*Li))*ui+Tsi^2*us / (2*Ci*Li)-Tsi*ii(k_old) / Ci;

[0174] / / CSR input voltage at time k+1;

[0175] isk2_ref=Psk2_ref*us / (1.5*norm(us)^2);

[0176] / / CSR AC side current reference value at time k+2;

[0177] iik1_ref=(isk2_ref-(1-Tsi^2 / (2*Ci*Li))*is_k1+Tsi / Li*ui_k1-Tsi / Li*us) / (Tsi^2 / (2*Ci*Li));

[0178] g = zeros(1,9);

[0179] / / CSR input current reference value at time k+1;

[0180] for i=1:9

[0181] g(i)=norm(iik1_ref-ii(i))^2;

[0182] / / Cost function;

[0183] end

[0184] [~,x_opt]=min(g);

[0185] state_opt = S(x_opt,:);

[0186] k_old = x_opt;

[0187] S1 = state_opt(1,1);

[0188] S2 = state_opt(1,2);

[0189] S3 = state_opt(1,3);

[0190] S4 = state_opt(1,4);

[0191] S5 = state_opt(1,5);

[0192] S6 = state_opt (1, 6);

[0193] / / Traverse the tour;

[0194] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A control method based on a current source rectifier, characterized in that: The method comprises: Acquire sampling data of a current-source rectifier at a first moment, and calculate input current data of the current-source rectifier at the first moment, wherein the input current data is determined according to the switch state of a rectifier bridge in the current-source rectifier at a previous moment; the sampling data includes grid-side voltage, grid-side current and AC capacitor voltage data; Inputting the sampled data and input current data into a pre-established prediction model to predict the state variables of the sampled data at a target time; Calculating the grid-side input current based on the state variable and the input current corresponding to different switch states; Based on the instantaneous power theory, proportional-integral control is used on the DC side of the current source rectifier to calculate the grid-side reference current; A cost model is established based on the grid-side reference current and the grid-side input current, and the switching state corresponding to the minimum value calculated by the cost model is used to control the rectification output of the current-source rectifier at the target time.

2. The control method based on the current source rectifier according to claim 1, characterized in that: The method further comprises: Acquire the grid-side current and the AC-side capacitor voltage of the current-source rectifier as state variables, and acquire the grid voltage and the current input to the current-source rectifier as control variables; Constructing a state space equation in continuous time based on the state variables and control variables; The state space equation is discretized to obtain the prediction model.

3. The control method based on the current source rectifier according to claim 2, characterized in that: The switch state corresponding to the minimum value calculated by the cost model controls the rectification output of the current source rectifier at the target time, including: Determining a corresponding relationship between a switch state of the rectifier bridge and an input current of the current-source rectifier; Traversing all the vector sequences of the switch states based on the state variable to determine the vector sequence value corresponding to the minimum value calculated by the cost model at the target moment; The bridge arm of the rectifier bridge is controlled to be turned off based on the vector sequence value.

4. The control method based on the current source rectifier according to claim 1, characterized in that: The method of calculating the grid-side reference current by using proportional-integral control on the DC side of the current-source rectifier based on the instantaneous power theory includes: Determining an active power reference value of the current source rectifier based on instantaneous power theory; Based on the DC side of the current source rectifier, a proportional-integral calculation formula is used to control the given active power reference value to calculate the grid-side reference current.

5. The control method based on the current source rectifier according to claim 1, characterized in that: The prediction model is calculated using the following calculation formula, which includes: In the formula, i g(k+1) 、u c(k+1) is the state variable at the target time, i g(k) 、u c(k) 、v g(k) is the sampling data at the first moment, i i(k) is the current data, T ac is the sampling time of the state variables of the AC side of the current source rectifier, C ac is the capacitance value of the AC side of the current source rectifier, L ac is the inductance value of the AC side of the current type rectifier.

6. The control method based on the current source rectifier according to claim 4, characterized in that: The proportional integral calculation formula includes: In the formula, is the grid-side current reference value, P ref is the active power reference value, i gα_ref is the α-axis component of the grid-side current reference value in the two-phase stationary coordinate system, i gβ _ref is the β-axis component of the grid-side current reference value in the two-phase stationary coordinate system, v gα is the α-axis component of the grid-side voltage value in the two-phase stationary coordinate system, v gβ is the β-axis component of the grid-side voltage value in the two-phase stationary coordinate system, and j is the rotation factor.

7. The control method based on the current source rectifier according to claim 6, characterized in that: The cost model is established based on the grid-side reference current and the grid-side input current, wherein the calculation formula of the cost model includes: In the formula, is the grid-side reference current, i g(k+2) is the grid-side input current.

8. A control device based on a current source rectifier, characterized in that: The device comprises: An acquisition module, used to acquire sampling data of a current-source rectifier at a first moment, and calculate input current data of the current-source rectifier at the first moment, wherein the input current data is determined according to the switch state of a rectifier bridge in the current-source rectifier at a previous moment; the sampling data includes grid-side voltage, grid-side current and AC capacitor voltage data; A prediction module, used for inputting the sampled data and input current data into a pre-established prediction model to predict the state variables of the sampled data at a target time; A first calculation module, configured to calculate a grid-side input current based on the state variable and input currents corresponding to different switch states; A second calculation module is used to calculate the grid-side reference current by using proportional-integral control on the DC side of the current-source rectifier based on instantaneous power theory; The control module is used to establish a cost model based on the grid-side reference current and the grid-side input current, and control the rectification output of the current-source rectifier at the target time using the switch state corresponding to the minimum value calculated by the cost model.

9. An electronic device, characterized in that: The electronic device includes a memory and a processor, wherein the memory stores program codes that can be run on the processor, and when the program codes are executed by the processor, the control method based on the current-source rectifier according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program codes, and the program codes can be called by one or more processors to execute the control method based on the current-source rectifier according to any one of claims 1 to 7.

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