A DC transformer control system and control method

Abstract

The present invention discloses a DC transformer control system and control method. The DC transformer control system includes: a central controller and several module controllers connected by optical fibers; the module controllers correspond one-to-one with the power modules; the central controller obtains the operating data of the several power modules and obtains the corresponding modulation waves of the power modules; the central controller sends control instructions to the several module controllers according to a preset period, the control instructions including the modulation wave, the power module number, and the power module status information; the module controllers obtain a triangular carrier based on the power module number and the power module status information, and compare and calculate the triangular carrier with the modulation wave to obtain the control command of the power module. By adopting a two-layer controller architecture, the communication frequency is greatly reduced while ensuring control accuracy, reducing the computing power requirements of the main controller and the workload of the DC transformer main controller, thereby improving the operating efficiency of the DC transformer main controller.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment control, and in particular to a direct current transformer control system and a control method. Background Art

[0002] DC transformers typically utilize an IGBT modular structure, with the number of modules varying depending on the voltage level. Generally, the higher the voltage level, the greater the number of modules. To achieve a smoother curve, the switching frequency of the modular power elements is typically high, often switching thousands of times per second. This technical solution places high demands on the controller's computing power, communication speed, and frequency, placing a heavy workload on the DC transformer controller and reducing its operating efficiency. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a DC transformer control system and control method. By adopting a two-layer controller architecture of a central processing unit and a module controller, while ensuring control accuracy, the communication frequency is greatly reduced, the requirements for the computing power of the main controller are reduced, the workload of the DC transformer main controller is reduced, and the operating efficiency of the DC transformer main controller is improved.

[0004] To solve the above technical problems, a first aspect of an embodiment of the present invention provides a DC transformer control system, wherein the DC transformer includes a plurality of power modules, including: a central controller and a plurality of module controllers connected by optical fibers;

[0005] The module controller corresponds to the power module one by one;

[0006] The central controller acquires the operating data of the plurality of power modules and obtains the corresponding modulation waves of the power modules;

[0007] The central controller sends control instructions to the plurality of module controllers according to a preset period, wherein the control instructions include: a modulation wave, a power module number, and power module status information;

[0008] The module controller obtains a triangular carrier wave according to the power module number and the power module status information, and compares and calculates the triangular carrier wave with the modulated wave to obtain a control command for the power module.

[0009] Furthermore, the module controller performs traversal calculation on the power module status information to obtain the number of power module faults and the number of power module faults that are less than the power module position number, and calculates the offset angle of the power module triangular carrier.

[0010] Furthermore, the calculation formula for the offset angle θ of the triangular carrier of the power module is:

[0011] θ=(n-x1)*2π / (mx);

[0012] Where n is the module number corresponding to the submodule, m is the total number of DC transformer modules, x is the total number of faulty modules calculated by the submodule based on the module status information traversal, and x1 is the total number of faulty modules whose module numbers are smaller than this module number.

[0013] Furthermore, the control instruction further includes: a synchronization instruction for identifying a reference phase of the power module;

[0014] The issuing period of the synchronization instruction is positively correlated with the carrier period generated by the module controller;

[0015] After receiving the synchronization instruction, the module controller restores the corresponding triangular carrier to an initial state.

[0016] Furthermore, the sending period of the synchronization instruction is an integer multiple of the carrier period.

[0017] Accordingly, a second aspect of an embodiment of the present invention provides a DC transformer control method, which controls a DC transformer using any of the above-mentioned DC transformer control systems, wherein the DC transformer includes a plurality of power modules, and includes the following steps:

[0018] Obtain operating data of several power modules through the central controller;

[0019] Calculating a modulation wave of the power module according to the operating data;

[0020] Sending the control instruction containing the modulated wave to the corresponding module controller;

[0021] Controlling the module controller to obtain a triangular carrier of the power module according to the power module number and power module status information in the control instruction;

[0022] The triangular carrier wave and the modulated wave are compared and calculated to obtain a control command for the power module.

[0023] Furthermore, the control instructions also include: synchronization instructions;

[0024] The DC transformer control method further includes:

[0025] After receiving the synchronization instruction, the module controller restores the corresponding triangular carrier to an initial state.

[0026] The above technical solutions of the embodiments of the present invention have the following beneficial technical effects:

[0027] By adopting a two-layer controller architecture of a central processing unit and a module controller, while ensuring control accuracy, the communication frequency is greatly reduced, the requirements for the computing power of the main controller are lowered, the workload of the DC transformer main controller is reduced, and the operating efficiency of the DC transformer main controller is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of a DC transformer power module circuit provided by an embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of the DC transformer control system architecture provided by an embodiment of the present invention;

[0030] Figure 3 This is a flow chart of a DC transformer control method provided by an embodiment of the present invention;

[0031] Figure 4 This is a logic diagram of the DC transformer control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0032] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0033] Figure 1 This is a schematic diagram of a DC transformer power module circuit provided by an embodiment of the present invention.

[0034] Please refer to Figure 1 In this example, Q1-Q10 are controllable switch components, one of the power modules in the DC transformer. Q9 and Q10 form the high-side half-bridge 1, bridge B1 (Buck-Boost half-bridge), while Q1-Q4 form the high-side H-bridge. Q5-Q8 form the low-voltage H-bridge. The central controller monitors module operating parameters and calculates the modulation waveform for bridge B1. It also sends the power module numbers and status information for all power modules.

[0035] Figure 2 This is a schematic diagram of the DC transformer control system architecture provided by an embodiment of the present invention.

[0036] Please refer to Figure 2A first aspect of an embodiment of the present invention provides a DC transformer control system. The DC transformer includes several power modules, including a central controller and several module controllers connected by optical fibers. The module controllers correspond one-to-one with the power modules. The central controller acquires operating data of the power modules and obtains modulation waves for the corresponding power modules. The central controller sends control instructions to the module controllers at a preset period, the control instructions including the modulation wave, the power module number, and power module status information. The module controllers obtain a triangular carrier wave based on the power module number and power module status information, and compare and calculate the triangular carrier wave with the modulation wave to obtain control commands for the power modules.

[0037] The DC transformer control system is divided into two control levels: a central controller and module controllers. The central controller and module controllers are connected via optical fiber. Each module controller controls a power module.

[0038] The above-mentioned DC transformer control system adopts a two-layer controller architecture of a central processing unit and a module controller, which greatly reduces the communication frequency while ensuring control accuracy, reduces the requirements for the computing power of the main controller, reduces the workload of the DC transformer main controller, and improves the operating efficiency of the DC transformer main controller.

[0039] Specifically, the module controller performs traversal calculation on the power module status information, obtains the number of power module faults and the number of power module faults smaller than the power module position number, and calculates the offset angle of the power module triangular carrier.

[0040] Furthermore, the calculation formula for the offset angle θ of the triangular carrier of the power module is:

[0041] θ=(n-x1)*2π / (mx);

[0042] Where n is the module number corresponding to the submodule, m is the total number of DC transformer modules, x is the total number of faulty modules calculated by the submodule based on the module status information traversal, and x1 is the total number of faulty modules whose module numbers are smaller than this module number.

[0043] Specifically, as shown in Table 1, the control instructions include: a frame header, a modulated wave, a power module number, power module status information, other control instructions, and a checksum. Optionally, the control instructions also include: a synchronization instruction for identifying the reference phase of the power module; the issuance period of the synchronization instruction is positively correlated with the carrier period generated by the module controller; upon receiving the synchronization instruction, the module controller restores its corresponding triangular carrier to its initial state.

[0044] Furthermore, the sending period of the synchronization instruction is an integer multiple of the carrier period. Preferably, the sending period of the synchronization instruction is more than 10 times the carrier period.

[0045] Figure 3 This is a flow chart of a DC transformer control method provided by an embodiment of the present invention;

[0046] Figure 4 This is a logic diagram of the DC transformer control method provided by an embodiment of the present invention.

[0047] Accordingly, please refer to Figure 3 and Figure 4 A second aspect of an embodiment of the present invention provides a method for controlling a DC transformer, wherein a DC transformer is controlled by any of the above-mentioned DC transformer control systems, wherein the DC transformer includes a plurality of power modules, and the method includes the following steps:

[0048] S100: Obtain operating data of several power modules through a central controller.

[0049] S200: Calculate and obtain a modulation wave of the power module based on the operating data.

[0050] S300: Sending a control instruction including a modulation wave to a corresponding module controller.

[0051] S400 , the control module controller obtains a triangular carrier of the power module according to the power module number and power module status information in the control instruction.

[0052] S500: Compare and calculate the triangular carrier wave and the modulated wave to obtain a control command for the power module.

[0053] The above-mentioned DC transformer control method adopts a two-layer controller architecture of a central processing unit and a module controller, which greatly reduces the communication frequency while ensuring control accuracy, reduces the requirements for the computing power of the main controller, reduces the workload of the DC transformer main controller, and improves the operating efficiency of the DC transformer main controller.

[0054] Specifically, the module controller periodically checks the received power module status information. If the status is inconsistent with the previous status, it performs a traversal calculation. This traversal calculates the total number of power module faults and the number of faulty modules with a lower number than the current power module. Assuming there are m power modules, m bits are used to represent the power module status. Each bit corresponds to a power module, set to 1 if a module is faulty, and 0 otherwise. The power modules are arranged sequentially according to their number.

[0055] The offset angle of the power module is calculated according to the formula θ = (n-x1) * 2π / (mx), and the corresponding triangular carrier is generated. The generated triangular carrier is compared with the modulated wave to obtain the control instruction of the power module.

[0056] Furthermore, the control instructions also include: synchronization instructions. Therefore, the above DC transformer control method also includes:

[0057] After receiving the synchronization instruction, the module controller restores its corresponding triangular carrier to the initial state.

[0058] The embodiment of the present invention is intended to protect a DC transformer control system and control method. The DC transformer includes several power modules. The DC transformer control system includes: a central controller and several module controllers connected by optical fibers; the module controllers correspond to the power modules one-to-one; the central controller obtains the operating data of the several power modules and obtains the modulation wave of the corresponding power modules; the central controller sends control instructions to the several module controllers according to a preset period, and the control instructions include: modulation wave, power module number and power module status information; the module controller obtains a triangular carrier according to the power module number and power module status information, and compares and calculates the triangular carrier with the modulation wave to obtain the control command of the power module. The above technical solution has the following effects:

[0059] By adopting a two-layer controller architecture of a central processing unit and a module controller, while ensuring control accuracy, the communication frequency is greatly reduced, the requirements for the computing power of the main controller are lowered, the workload of the DC transformer main controller is reduced, and the operating efficiency of the DC transformer main controller is improved.

[0060] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

Claims

1. A DC transformer control system, characterized in that: The DC transformer includes several power modules, including: a central controller and several module controllers connected by optical fibers; The module controller corresponds to the power module one by one; The central controller acquires the operating data of the plurality of power modules and obtains the corresponding modulation waves of the power modules; The central controller sends control instructions to the plurality of module controllers according to a preset period, wherein the control instructions include: a modulation wave, a power module number, and power module status information; The module controller obtains a triangular carrier wave according to the power module number and the power module status information, and compares and calculates the triangular carrier wave with the modulated wave to obtain a control command for the power module; The module controller performs traversal calculation on the power module status information to obtain the number of power module faults and the number of power module faults less than the power module position number, and calculates the offset angle of the power module triangular carrier; The calculation formula for the offset angle θ of the triangular carrier of the power module is: θ=(n-x1)*2π / (mx); Where n is the module number corresponding to the submodule, m is the total number of DC transformer modules, x is the total number of faulty modules calculated by the submodule based on the module status information traversal, and x1 is the total number of faulty modules whose module numbers are smaller than this module number.

2. The DC transformer control system according to claim 1, characterized in that: The control instructions further include: a synchronization instruction for identifying a reference phase of the power module; The issuing period of the synchronization instruction is positively correlated with the carrier period generated by the module controller; After receiving the synchronization instruction, the module controller restores the corresponding triangular carrier to an initial state.

3. The DC transformer control system according to claim 2, characterized in that: The sending period of the synchronization instruction is an integer multiple of the carrier period.

4. A DC transformer control method, characterized in that: Controlling a DC transformer by using the DC transformer control system according to any one of claims 1 to 3, wherein the DC transformer includes a plurality of power modules, comprises the following steps: Obtain operating data of several power modules through the central controller; Calculating a modulation wave of the power module according to the operating data; Sending the control instruction containing the modulated wave to the corresponding module controller; Controlling the module controller to obtain a triangular carrier of the power module according to the power module number and power module status information in the control instruction; The triangular carrier wave and the modulated wave are compared and calculated to obtain a control command for the power module.

5. The DC transformer control method according to claim 4, characterized in that: The control instructions also include: synchronization instructions; The DC transformer control method further includes: After receiving the synchronization instruction, the module controller restores the corresponding triangular carrier to an initial state.

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