ANPC neutral point potential balance control circuit, method and device, chip and electronic equipment

Abstract

The invention discloses an ANPC neutral point potential balance control circuit, method and device, a chip and electronic equipment. The circuit comprises an IGBT switching circuit and an inductance circuit, and the IGBT switching circuit is connected with the inductance circuit and used for generating a modulation signal of the IGBT switching circuit through a voltage parameter value of the IGBT switching circuit and a current parameter value of the inductance circuit; and generating a driving signal of the IGBT switching circuit according to the modulation signal of the IGBT switching circuit. According to the exemplary embodiment, the precision of neutral-point potential balance control is improved, and the complexity of control is reduced.

Description

Technical Field

[0001] The present application relates to the field of energy storage control technology, and in particular to an ANPC midpoint potential balance control circuit, method, device, chip and electronic device. Background Art

[0002] ANPC inverter is an active neutral point clamped inverter, which is widely used in photovoltaic, energy storage and other converters to balance the neutral point potential. The control method in the related technology has high control complexity and inaccurate control effect.

[0003] It should be noted that the statements herein merely provide background information related to the present application and do not necessarily constitute prior art. Summary of the invention

[0004] In view of the above problems, the present application proposes an ANPC midpoint potential balance control circuit, method, device, chip and electronic device that overcome the above problems or at least partially solve the above problems.

[0005] The present application embodiment adopts the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides an ANPC midpoint potential balance control circuit, the circuit comprising an IGBT switching circuit and an inductor circuit, the IGBT switching circuit being connected to the inductor circuit and configured to generate a modulation signal of the IGBT switching circuit through a voltage parameter value of the IGBT switching circuit and a current parameter value of the inductor circuit; and to generate a drive signal of the IGBT switching circuit according to the modulation signal of the IGBT switching circuit.

[0007] Preferably, the IGBT switching circuit includes: a first IGBT switching circuit, a second IGBT switching circuit and a PI controller, wherein the PI controller is used to receive a voltage difference parameter between the first IGBT switching circuit and the second IGBT switching circuit; and generate a modulation signal of the IGBT switching circuit according to the voltage difference parameter and the current parameter value of the inductance circuit.

[0008] Preferably, the first IGBT switching circuit is also used to control the on and off of the first IGBT switching circuit in response to a driving signal of the IGBT switching circuit; the second IGBT switching circuit is also used to control the on and off of the second IGBT switching circuit in response to a driving signal of the IGBT switching circuit; and the current parameter value of the inductance circuit is controlled according to the on and off of the first IGBT switching circuit and the on and off of the second IGBT switching circuit.

[0009] In a second aspect, an embodiment of the present application further provides an ANPC midpoint potential balance control method, comprising a balance control circuit as described in the first aspect, wherein the balance control method comprises: respectively sampling the upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value; inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal; and performing balance control on the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal.

[0010] Preferably, the step of inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal comprises: performing a first difference operation on the upper tube capacitor voltage value and the lower tube capacitor voltage value, and then inputting the difference into a first-stage controller in the multi-stage controller to obtain a first control quantity; performing a second difference operation on the first control quantity and the inductor current value, and then inputting the difference into a second-stage controller in the multi-stage controller to obtain a modulation signal.

[0011] Preferably, the comparison signal includes a triangular wave signal, and the balancing control of the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal includes: obtaining a drive signal after signal processing the modulation signal and the triangular wave signal; and controlling the on and off of the first IGBT switching circuit and the second IGBT switching circuit by the drive signal.

[0012] In a third aspect, an embodiment of the present application further provides an ANPC midpoint potential balance control device, the balance control device comprising: a first unit, respectively sampling the upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value; a second unit, inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal; a third unit, performing balance control on the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal.

[0013] In a fourth aspect, an embodiment of the present application further provides a chip, comprising an ANPC midpoint potential balance control circuit, wherein the control circuit is configured to execute a method according to any one of the methods described in the second aspect.

[0014] In a fifth aspect, an embodiment of the present application further provides an electronic device, comprising the chip according to the fourth aspect.

[0015] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects:

[0016] By setting an IGBT switch circuit and an inductor circuit in the ANPC circuit and controlling the switch state of the IGBT by generating a drive signal of the IGBT switch circuit, the fluctuation of the midpoint potential of the ANPC circuit is reduced and the voltage quality of the AC side output is improved.

[0017] The above description of the technical solution of the present application is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0019] Figure 1 This is the NPC topology diagram in the embodiment of this application;

[0020] Figure 2 This is the ANPC topology diagram in the embodiment of this application;

[0021] Figure 3 ANPC DC side capacitor topology diagram in the embodiment of the present application;

[0022] Figure 4 ANPC midpoint potential balance control topology diagram of the additional circuit in the embodiment of the present application;

[0023] Figure 5 This is a block diagram of the ANPC midpoint potential balance control of the external circuit in the embodiment of the present application;

[0024] Figure 6 This is a flow chart of the ANPC midpoint potential balance control method in the embodiment of the present application;

[0025] Figure 7 This is a schematic diagram of an ANPC midpoint potential balance control device in an embodiment of the present application;

[0026] Figure 8 This is a midpoint potential fluctuation diagram in the embodiment of the present application;

[0027] Fig. 9 This is a graph of capacitor voltage fluctuation in the embodiment of the present application;

[0028] Fig.10 This is a diagram of the neutral point potential fluctuation after the inductance is adjusted in the embodiment of the present application;

[0029] Fig.11 This is a schematic diagram of the structure of an electronic device in an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0031] The technical terms involved in this application are as follows:

[0032] ANPC, (Active Neutral Point Clamped) active neutral point clamp;

[0033] PI, (Proportional-Integral) proportional-integral;

[0034] like Figure 1 As shown in Figure 1, the neutral point clamped (NPC) three-level topology is a widely used multi-level topology. The biggest disadvantage of the NPC topology is that the inner tube is on longer than the outer tube, resulting in uneven loss of power devices, which in turn affects the service life of the NPC.

[0035] like Figure 2 As shown in the figure, the active neutral point clamped (ANPC) three-level topology is based on the NPC topology, and the two diodes are replaced with IGBT fully controlled devices. Its topology structure is as follows: Figure 1 As shown. Compared with the neutral point clamp type (NPC), the commutation modes of the ANPC inverter have been expanded from the original 8 to 32, ensuring the loss balance between the switch tubes. However, both NPC and ANPC face the problem of unbalanced neutral point O potential, that is, the voltage of capacitor C1 and the voltage of capacitor C2 are not equal. The unbalanced neutral point potential will affect the life of the DC side capacitor, increase the AC output harmonics, cause unequal voltages on the IGBT, and even damage the device.

[0036] In response to the above technical problems, the applicant has conducted relevant research and found that the current methods for controlling the neutral point potential balance are as follows:

[0037] Solution 1: Zero-sequence voltage injection method

[0038] The zero-sequence voltage injection method is a software control algorithm that does not require an external application circuit. Injecting zero-sequence voltage in a three-phase system has no effect on the line voltage. The midpoint voltage fluctuation can be controlled by injecting the same zero-sequence voltage into the three phases ABC.

[0039] Solution 2: Space Vector Pulse Width Modulation

[0040] The midpoint potential control methods of space vector pulse width modulation mainly include three-vector pulse width modulation (NTSVPWM) and virtual space vector pulse width modulation (VSVPWM).

[0041] The above technical solution has the following problems, and the effect of midpoint potential control is not ideal:

[0042] Disadvantages of Solution 1:

[0043] This method is subject to certain conditions. A basic condition is that the reference voltage after superimposing the zero-sequence component cannot cause the system to overmodulate. In some cases, the calculated zero-sequence component does not meet this condition. At this time, this method can only suppress the fluctuation of the midpoint voltage. This method is limited to three-phase systems and cannot be applied to single-phase systems. In addition, this method will inject a certain amount of harmonics into the AC measurement.

[0044] Disadvantages of Solution 2:

[0045] By adjusting the small vector duty cycle, NTSVPWM can balance the midpoint potential within a certain range of load power factor and modulation ratio. However, in the working range of high modulation ratio and low power factor, this control strategy has an uncontrollable area of ​​midpoint potential, and the output waveform produces low-order harmonics. VSVPWM can achieve balanced control of midpoint voltage in any working range by redefining the space vector, but this method increases the switching loss of the converter and the harmonics of the output voltage, and the software control complexity is high.

[0046] Aiming at the current situation that the midpoint potential balance control effect is poor and the accuracy is low in the existing technology, an automated and universal ANPC midpoint potential balance control circuit is designed. The circuit improves the accuracy of midpoint potential balance control and reduces the complexity of software control by adding IGBT switching circuit and inductor circuit in the ANPC topology.

[0047] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0048] The embodiments of the present application provide an ANPC midpoint potential balance control circuit, method, device, chip and electronic device, such as Figure 4 As shown, a schematic diagram of the ANPC midpoint potential balance control circuit in an embodiment of the present application is provided. Figure 4 and Figure 5 , the control circuit includes an IGBT switch circuit and an inductor circuit, the IGBT switch circuit is connected to the inductor circuit, and is used to generate a modulation signal of the IGBT switch circuit through a voltage parameter value of the IGBT switch circuit and a current parameter value of the inductor circuit; and generate a drive signal of the IGBT switch circuit according to the modulation signal of the IGBT switch circuit. Wherein, the IGBT switch circuit includes: a first IGBT switch circuit IGBT1, a second IGBT switch circuit IGBT2 and a PI controller, wherein the PI controller includes a two-stage PI controller, and the PI controller is used to receive a voltage difference parameter between the first IGBT switch circuit and the second IGBT switch circuit; and generate a modulation signal of the IGBT switch circuit according to the voltage difference parameter and the current parameter value of the inductor circuit. The first IGBT switching circuit is also used to control the on and off of the first IGBT switching circuit in response to a driving signal of the IGBT switching circuit; the second IGBT switching circuit is also used to control the on and off of the second IGBT switching circuit in response to a driving signal of the IGBT switching circuit; and the current parameter value of the inductance circuit is controlled according to the on and off of the first IGBT switching circuit and the on and off of the second IGBT switching circuit.

[0049] It can be understood that the present application improves the accuracy and balancing speed of the midpoint potential balancing and reduces the complexity of software control through the midpoint potential balancing control circuit. In addition, the control circuit does not rely on the parameter setting of the inductor, which improves the versatility and can be applied not only to single-phase ANPC but also to three-phase ANPC topology.

[0050] Based on the above ANPC midpoint potential balance control circuit, the present disclosure further provides an ANPC midpoint potential balance control method 600, wherein the control method 600 at least includes the following steps S610 to S630:

[0051] Step S610: Sample the upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit respectively to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value. Figure 3 , the neutral point potential of ANPC is analyzed as follows:

[0052] The topology of the ANPC DC capacitor side is shown in the figure below. Assume the midpoint potential is V o .

[0053] The calculation formulas for current I1 and current I2 are:

[0054]

[0055] According to Kirchhoff's current law (KCL circuit principle), I = -I1-I2, and since C1 = C2 = C dc , we can get:

[0056]

[0057] From the above formula, the formula for the midpoint potential is as follows:

[0058]

[0059] Based on the above analysis, it can be seen that the midpoint potential will be affected by the midpoint current and change with the accumulation of the midpoint current I. Through space vector pulse width modulation, it is found that the medium vector and the small vector have one or two phases connected to the midpoint, causing the current to flow into or out of the midpoint. Pulse width modulation and space vector pulse width modulation are essentially consistent, so the neutral point potential of ANPC will fluctuate and needs to be controlled.

[0060] like Figure 4 As shown, during the control process, it is necessary to sample the voltage of capacitor C1 and capacitor C2 to obtain the voltage U across capacitor C1 and capacitor C2. c1 and U c2 , sample the inductor L and obtain the sampled current I L .

[0061] Step S120, inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal;

[0062] In some embodiments, the step of inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value, and the inductor current value into a multi-stage controller to obtain a modulation signal includes: performing a first difference operation on the upper tube capacitor voltage value and the lower tube capacitor voltage value, and then inputting the difference into a first-stage controller in the multi-stage controller to obtain a first control quantity; performing a second difference operation on the first control quantity and the inductor current value, and then inputting the difference into a second-stage controller in the multi-stage controller to obtain a modulation signal.

[0063] In some embodiments, the comparison signal includes a triangular wave signal, and the balancing control of the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal includes: obtaining a driving signal after signal processing the modulation signal and the triangular wave signal; and controlling the on and off of the first IGBT switch circuit and the second IGBT switch circuit by the driving signal.

[0064] refer to Figure 4 and Figure 5, by controlling the switches of IGBT1 and IGBT2, the voltages of capacitors C1 and C2 are controlled. In one example, when the voltage of capacitor C1 is greater than the capacitor voltage C2, IGBT1 is turned on to charge the inductor L. When IGBT1 is turned off, due to the freewheeling of the inductor, the inductor charges C2 and increases the voltage of C2. On the contrary, when the capacitor voltage C2 is greater than the capacitor voltage C1, IGBT2 is turned on to charge the inductor. When IGBT2 is turned off, the inductor charges the capacitor C1. Based on this, the midpoint potential balance and stability can be guaranteed.

[0065] In one example, the goal of the control circuit is to make the capacitor voltage U c1 and U c2 equal, achieving dynamic balance and preventing the capacitor voltage U from c1 and U c2 The difference between the values ​​becomes larger, which in turn affects the output side. To control the capacitor voltage U c1 and U c2 If the inductor current I L PI controller can realize zero-static-error control of DC quantity. c1 and U c2 Perform PI control, and the output of the PI controller is then combined with the inductor current I L After comparison and passing through the PI controller, the modulation signals of the IGBT1 and IGBT2 switches can be obtained.

[0066] The PI controller consists of a proportional link and an integral link. Proportional link: that is, it proportionally reflects the deviation signal of the control system. Once the deviation occurs, the controller immediately produces a control action to reduce the deviation. Usually, as the proportional gain value increases, the overshoot of the closed-loop system increases and the system response speed increases. However, when the proportional gain increases to a certain extent, the system becomes unstable. Integral link: It is mainly used to eliminate static errors and improve the system's zero-difference degree. The strength of the integral effect depends on the integral constant integral gain. The larger the integral gain, the stronger the integral effect, and vice versa. The smaller the overshoot of the closed-loop system, the slower the system response speed.

[0067] Step S130 , performing balance control on the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal.

[0068] By comparing the modulation signal generated above with the triangular wave, the driving signals of IGBT1 and IGBT2 can be obtained to control the on and off of IGBT1 and IGBT2, thereby controlling the current flowing through the inductor L.

[0069] refer to Figure 5 In one example, the ANPC midpoint potential balance control method includes the following steps:

[0070] Step 1: Collect the voltage value U of capacitor C1 c1 , the voltage value of capacitor C2 is U c2 And the inductor current value I L ,

[0071] Step 2: Set the voltage value of capacitor C1 to U c1 and the voltage value U of capacitor C2 c2 Make a difference to obtain the capacitor voltage difference;

[0072] Step 3: Input the capacitor voltage difference into the first PI controller to obtain the first control variable, that is, the control current value I c ;

[0073] Step 4: Change the control current value I in step 3 to c and the inductor current value I in step 1 L Make a difference and get the current difference I m .

[0074] Step 5: The current difference I m Input the second PI controller to obtain the control voltage U C ,Right now Figure 5 In one example, the amplitude of the modulation signal is set to [-1, 1] modulation frequency or the amplitude range is set as required.

[0075] Step 6: Process the modulation signal and the triangular wave signal to obtain a driving signal, wherein the driving signal may be in the form of a switch signal of on and off.

[0076] In one example, if the driving signal is 1, IGBT1 is controlled to be turned on, and if the driving signal is -1, IGBT2 is driven to be turned on.

[0077] It can be understood that the voltages of capacitors C1 and C2 are controlled by switching IGBT1 and IGBT2. When the voltage of capacitor C1 is greater than capacitor voltage C2, IGBT1 is turned on to charge inductor L. When IGBT1 is turned off, due to the freewheeling of the inductor, the inductor charges C2 and increases the voltage of C2. On the contrary, when capacitor voltage C2 is greater than capacitor voltage C1, IGBT2 is turned on to charge the inductor. When IGBT2 is turned off, the inductor charges capacitor C1. Repeatedly, the midpoint potential balance can be guaranteed to be stable.

[0078] The present application also provides an ANPC midpoint potential balance control device 700, such as Figure 7 As shown, a schematic diagram of the structure of the ANPC midpoint potential balance control in an embodiment of the present application is provided, wherein the device 700 comprises at least: a first unit 710, a second unit 720 and a third unit 730, wherein:

[0079] In one embodiment of the present application, the first unit 710 is specifically used to: respectively sample the upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value.

[0080] In one embodiment of the present application, the second unit 720 is specifically used to: input the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal.

[0081] In one embodiment of the present application, the third unit 730 is specifically used to: balance and control the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal.

[0082] It can be understood that the above-mentioned ANPC midpoint potential balance control device can implement the various steps of the ANPC midpoint potential balance control method provided in the aforementioned embodiments, and the relevant explanations about the ANPC midpoint potential balance control method are applicable to the ANPC midpoint potential balance control device and will not be repeated here.

[0083] In order to better illustrate the technical effects obtained by the above-mentioned ANPC midpoint potential balance control circuit, method and device, the following simulation is now performed:

[0084] ANPC topology of a single-phase external control circuit, DC voltage 540V, inductance L is 3mH, capacitor voltage U c1 The initial voltage is 270V, the capacitor voltage U c2 The initial voltage is 200 V and the simulation time is 1 second.

[0085] Voltage on capacitor U c1 and U c2 Sampling is performed to sample the inductor current. After sampling, the neutral point potential is controlled by using the ANPC neutral point potential balance control method disclosed in the present invention.

[0086] like Figure 8 The neutral point potential fluctuation diagram after the external circuit is shown. The neutral point potential fluctuation is less than 0.2V, and the neutral point balance can be achieved quickly before 0.03 seconds. The capacitor voltage U c1 and capacitor voltage U c2 Basically equal. The capacitor voltage fluctuation is as follows Fig. 9 shown.

[0087] In one example, the added inductance circuit is reduced from 1.5mH to 0.5mH, and the neutral point potential fluctuation is as follows Fig.10As shown in the figure, the neutral point potential can still be quickly stabilized after the inductance is reduced, and the midpoint potential fluctuation is less than 0.2V.

[0088] It can be understood that the ANPC midpoint potential balance control circuit, method and device disclosed in the present invention do not rely on the parameter setting of the inductor voltage and are more universal.

[0089] An embodiment of the present disclosure further provides a chip, which includes an ANPC midpoint potential balance control circuit, and the control circuit is configured to execute the above method.

[0090] Fig.11 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present application. Fig.11 At the hardware level, the electronic device includes a processor, and optionally also includes an internal bus, a network interface, and a memory. The memory may include a memory, such as a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage. Of course, the electronic device may also include hardware required for other services.

[0091] The processor, network interface and memory can be interconnected through an internal bus, which can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.11 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0092] The memory is used to store the program. Specifically, the program may include a program code, and the program code includes a computer operation instruction. The memory may include a memory and a non-volatile memory, and provides instructions and data to the processor.

[0093] The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it, forming an ANPC midpoint potential balance control device at the logical level. The processor executes the program stored in the memory and is specifically used to perform the following operations:

[0094] The upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit are sampled respectively to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value; the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value are input into a multi-stage controller to obtain a modulation signal; and the midpoint potential in the ANPC circuit is balanced and controlled according to the modulation signal and the comparison signal.

[0095] The above application Figure 6 The method performed by the ANPC midpoint potential balance control device disclosed in the illustrated embodiment can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor for execution, or a combination of hardware and software modules in the decoding processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0096] The electronic device may also perform Figure 6 ANPC midpoint potential balance control device is implemented in the method, and the ANPC midpoint potential balance control device is implemented in the method Figure 6 The functions of the illustrated embodiment will not be described in detail in the embodiments of the present application.

[0097] The present application also provides a computer-readable storage medium, which stores one or more programs, wherein the one or more programs include instructions, which, when executed by an electronic device including multiple application programs, enable the electronic device to execute Figure 6 The method performed by the ANPC midpoint potential balance control device in the illustrated embodiment is specifically used to perform:

[0098] The upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit are sampled respectively to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value; the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value are input into a multi-stage controller to obtain a modulation signal; and the midpoint potential in the ANPC circuit is balanced and controlled according to the modulation signal and the comparison signal.

[0099] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0100] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0101] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0102] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0103] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0104] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0105] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0106] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0107] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0108] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. An ANPC midpoint potential balance control circuit, characterized in that: The circuit includes an IGBT switch circuit and an inductor circuit, wherein the IGBT switch circuit is connected to the inductor circuit. Generate a modulation signal of the IGBT switching circuit by using a voltage parameter value of the IGBT switching circuit and a current parameter value of the inductor circuit; A drive signal of the IGBT switch circuit is generated according to the modulation signal of the IGBT switch circuit.

2. The circuit according to claim 1, characterized in that The IGBT switch circuit comprises: a first IGBT switch circuit, a second IGBT switch circuit and a PI controller, wherein the PI controller is used to receive a voltage difference parameter between the first IGBT switch circuit and the second IGBT switch circuit; A modulation signal of the IGBT switch circuit is generated according to the voltage difference parameter and the current parameter value of the inductor circuit.

3. The circuit according to claim 2, characterized in that: The first IGBT switch circuit is further used to control the on and off of the first IGBT switch circuit in response to a drive signal of the IGBT switch circuit; The second IGBT switch circuit is further used to control the on and off of the second IGBT switch circuit in response to a drive signal of the IGBT switch circuit; According to the on / off of the first IGBT switch circuit and the on / off of the second IGBT switch circuit, a current parameter value of the inductor circuit is controlled.

4. A method for controlling the midpoint potential balance of an ANPC, characterized in that: The balance control circuit according to any one of claims 1 to 3, wherein the balance control method comprises: Respectively sampling the upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value; Inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal; The midpoint potential in the ANPC circuit is balanced and controlled according to the modulation signal and the comparison signal.

5. The method according to claim 4, characterized in that: The step of inputting the upper tube capacitor voltage value, the lower tube capacitor voltage value, and the inductor current value into a multi-stage controller to obtain a modulation signal includes: After performing a first difference operation on the upper tube capacitor voltage value and the lower tube capacitor voltage value, the difference is input into a first stage controller in the multi-stage controller to obtain a first control variable; After performing a second difference operation on the first control variable and the inductor current value, the difference is input into a second-stage controller in the multi-stage controller to obtain a modulation signal.

6. The method according to claim 5, characterized in that The comparison signal includes a triangular wave signal, and the midpoint potential in the ANPC circuit is balanced and controlled according to the modulation signal and the comparison signal, including: After performing signal processing on the modulation signal and the triangular wave signal, a driving signal is obtained; The first IGBT switch circuit and the second IGBT switch circuit are controlled to be turned on and off by the driving signal.

7. An ANPC midpoint potential balance control device, characterized in that: The balance control device comprises: The first unit samples the upper tube capacitor voltage, the lower tube capacitor voltage and the current of the inductor circuit in the ANPC circuit respectively to obtain the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value; The second unit inputs the upper tube capacitor voltage value, the lower tube capacitor voltage value and the inductor current value into a multi-stage controller to obtain a modulation signal; The third unit performs a balance control on the midpoint potential in the ANPC circuit according to the modulation signal and the comparison signal.

8. A chip, characterized in that: The chip comprises an ANPC midpoint potential balancing control circuit, and the control circuit is configured to execute the method according to any one of claims 4 to 6.

9. An electronic device, characterized in that: Comprising the chip according to claim 8.

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