Non-isolated power supply parallel circulating current suppression method and device

Abstract

The invention discloses a non-isolated power supply parallel circulating current suppression method and device. The method comprises the following steps: executing the following processing on each non-isolated power supply module in a plurality of non-isolated power supply modules; acquiring a current acquisition result through a current acquisition circuit of the currently processed non-isolated power supply module; determining a reference adjustment value of a bus voltage of a DC bus of the non-isolated power supply module according to the current acquisition result; determining a control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the reference adjustment value; a control signal is sent to a controlled device of a boost circuit in the non-isolated power supply module; and detecting that a difference value of two bus voltages corresponding to any two non-isolated power supply modules in the plurality of non-isolated power supply modules is smaller than a preset difference value. According to the invention, the problem of parallel circulating current caused by bus voltage difference can be effectively suppressed, and the risk of overcurrent failure caused by the parallel circulating current is reduced.

Description

Technical Field

[0001] The present application relates to the field of battery management technology, and in particular to a method and device for suppressing parallel circulating current of a non-isolated power supply. Background Art

[0002] With the rapid development of power electronics technology, non-isolated power modules have been widely used in various fields due to their high efficiency, low cost and high stability. Especially in the field of data center power supply, the new phase-shifting transformer + non-isolated power supply solution has improved the efficiency by nearly 2%. Compared with the general isolation module power supply, it has higher efficiency and better system stability. In the new data center energy solution, since the cost of power energy consumption accounts for a high proportion of the total cost, the phase-shifting transformer + non-isolated power supply module has significant advantages. However, when the power modules of the non-isolated topology are used in parallel, the input and output are connected in parallel, and it is easy to generate circulating current between the power modules. The circulating current is superimposed on the power current of the module itself, and flows through some semiconductor power devices and internal PCB traces. If the total input current after superposition is greater than the maximum allowable input current of the selected module device, it is easy to cause overheating and failure of some modules.

[0003] The current strategy for suppressing circulating current in parallel with power modules requires slow adjustment through communication between power modules. Under the condition of sudden dynamic load, the current adjustment strategy will generate large circulating current spikes due to communication delay between the power modules, thus posing a risk of overcurrent failure to all devices on the circulating current path. Summary of the invention

[0004] The present application provides a method and device for suppressing circulating current in parallel of a non-isolated power supply, by setting a consistent bus voltage for multiple parallel power modules, and each module then adjusts the bus voltage according to the positive and negative current difference between the positive terminal current of the positive output terminal of the buck circuit and the negative terminal current of the negative output terminal, so as to achieve slow steady-state circulating current regulation; and, according to the inductor current of the output terminal of the input inductor, the bus voltage is drooped to achieve rapid suppression of dynamic circulating current spikes. It is possible to achieve circulating current suppression under all working conditions and balance the bus voltage of multiple modules, thereby improving the reliability and service life of the power module.

[0005] In the first aspect, an embodiment of the present application provides a method for suppressing parallel circulating current of a non-isolated power supply, which is applied to a controller of a DC / DC conversion circuit, wherein the DC / DC conversion circuit includes a three-phase current source, a plurality of non-isolated power supply modules in parallel, and a load, wherein the plurality of non-isolated power supply modules are respectively connected to the three-phase current source and the load; a single non-isolated power supply module includes a three-phase rectifier circuit, a current acquisition circuit, a boost circuit, and a buck circuit, wherein the controller is respectively connected to the current acquisition circuit and the boost circuit, wherein the boost circuit is connected to the buck circuit via a DC bus, wherein the current acquisition circuit is connected to an input end of the boost circuit, and wherein the current acquisition circuit is respectively connected to a positive output end and a negative output end of the buck circuit; wherein the method includes: Performing the following processing for each of the multiple non-isolated power supply modules, so that the difference between the two bus voltages corresponding to any two non-isolated power supply modules of the multiple non-isolated power supply modules is less than a preset difference; Acquire a current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end; Determine a reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module according to the current acquisition result; Determining a control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the reference adjustment value, wherein the controlled device includes a PWM controller; Sending the control signal to the controlled device of the boost circuit in the non-isolated power module; It is detected that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is smaller than the preset difference.

[0006] In the second aspect, an embodiment of the present application provides a non-isolated power supply parallel circulating current suppression device, which is applied to a controller of a DC / DC conversion circuit, wherein the DC / DC conversion circuit includes a three-phase current source, a plurality of non-isolated power supply modules in parallel, and a load, wherein the plurality of non-isolated power supply modules are respectively connected to the three-phase current source and the load; a single non-isolated power supply module includes a three-phase rectifier circuit, a current acquisition circuit, a boost circuit, and a buck circuit, wherein the controller is respectively connected to the current acquisition circuit and the boost circuit, wherein the boost circuit is connected to the buck circuit through a DC bus, wherein the current acquisition circuit is connected to the input end of the boost circuit, and wherein the current acquisition circuit is respectively connected to the positive output end and the negative output end of the buck circuit; wherein the device includes: A processing unit, configured to perform the following processing on each of the plurality of non-isolated power supply modules, so that a difference between two bus voltages corresponding to any two non-isolated power supply modules of the plurality of non-isolated power supply modules is less than a preset difference; A collection unit, used for acquiring a current collection result of the non-isolated power supply module through a current collection circuit of the non-isolated power supply module currently being processed, wherein the current collection result includes an inductor current at an input end of the boost circuit or a current at an output end of the buck circuit, and the current at the output end of the buck circuit includes a positive end current of the positive output end and a negative end current of the negative output end; A first determining unit, configured to determine a reference adjustment value of a bus voltage of a DC bus of the non-isolated power supply module according to the current acquisition result; A second determining unit, configured to determine a control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the reference adjustment value, wherein the controlled device includes a PWM controller; A sending unit, configured to send the control signal to the controlled device of the boost circuit in the non-isolated power supply module; The detection unit is used to detect that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is less than the preset difference.

[0007] In a third aspect, an embodiment of the present application provides an electronic device, comprising a processor, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, and the program includes instructions for executing the steps in the first aspect of the embodiment of the present application.

[0008] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program / instruction stored thereon, and the computer program / instruction is executed by a processor to implement the steps of the method described in the first aspect above.

[0009] It can be seen that in the embodiment of the present application, the controller first obtains the current acquisition result of the non-isolated power module through the current acquisition circuit of the non-isolated power module currently being processed; then, the reference adjustment value of the bus voltage of the DC bus of the non-isolated power module is determined according to the current acquisition result; then, the control signal for controlling the controlled device of the boost circuit in the non-isolated power module is determined according to the reference adjustment value; secondly, the control signal is sent to the controlled device of the boost circuit in the non-isolated power module; finally, it is detected that the difference between the two bus voltages corresponding to any two non-isolated power modules in the multiple non-isolated power modules is less than the preset difference. Compared with the existing circulating current suppression scheme for slow regulation through communication between multiple power supplies, it can realize the rapid suppression of dynamic circulating current peaks according to the current acquisition result, and realize the slow steady-state circulating current regulation, so as to realize the circulating current suppression under all working conditions and balance the bus voltage of multiple modules, which is conducive to improving the reliability and safety of the power module. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0011] Figure 1 is a circuit diagram of a DC / DC conversion circuit provided in an embodiment of the present application; Figure 2 It is a schematic diagram of a parallel structure of non-isolated power supply modules connected to a three-phase AC source provided by an embodiment of the present application; Figure 3 It is a schematic diagram of a parallel structure of non-isolated power supply modules connected to a DC source provided in an embodiment of the present application; Figure 4 It is a flowchart of the steps of a method for suppressing parallel circulating current of a non-isolated power supply provided in an embodiment of the present application; Figure 5 It is an overall flow chart of a method for suppressing parallel circulating current of a non-isolated power supply provided in an embodiment of the present application; Figure 6 This is a functional unit composition block diagram of a non-isolated power supply parallel circulating current suppression device provided in an embodiment of the present application; Figure 7It is a structural block diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0012] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. 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 creative work are within the scope of protection of this application.

[0013] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0014] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0015] In the embodiments of the present application, "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B can represent the following three situations: A exists alone; A and B exist at the same time; B exists alone. Among them, A and B can be singular or plural.

[0016] In the embodiment of the present application, the symbol " / " can indicate that the objects associated with each other are in an "or" relationship. In addition, the symbol " / " can also indicate a division sign, that is, performing a division operation. For example, A / B can indicate A divided by B.

[0017] In the embodiments of the present application, "equal to" can be used in conjunction with greater than, and is applicable to the technical solution adopted when greater than, and can also be used in conjunction with less than, and is applicable to the technical solution adopted when less than. When equal to is used in conjunction with greater than, it is not used in conjunction with less than; when equal to is used in conjunction with less than, it is not used in conjunction with greater than.

[0018] Currently, the existing strategy for suppressing the circulating current in parallel of power modules requires slow adjustment through communication between power modules. Under the condition of sudden dynamic load, the current adjustment strategy will generate large circulating current spikes due to communication delays between the power modules, thereby posing a risk of overcurrent failure to all devices on the circulating current path. It is difficult to meet the demand for suppressing the circulating current of multiple power modules in parallel.

[0019] In view of the above problems, an embodiment of the present application provides a method and device for suppressing parallel circulating current of a non-isolated power supply. The embodiment of the present application is described in detail below in conjunction with the accompanying drawings.

[0020] See also Figure 1 , Figure 1 is a circuit diagram of a DC / DC conversion circuit provided in an embodiment of the present application. Figure 1 As shown, the DC / DC conversion circuit includes two non-isolated power supply modules connected in parallel.

[0021] The input ends of the two non-isolated power modules are connected in parallel to a three-phase power grid, and the output ends are connected in parallel to a load.

[0022] Among them, the first non-isolated power supply module includes a first three-phase rectifier circuit, a first boost circuit, a first buck circuit and a load connected in sequence. The first three-phase rectifier current controls and rectifies the A1 phase current, B1 phase current and C1 phase current from the three-phase power grid through three-phase forward diodes Da1+, Db1+ and DC1+ respectively to obtain a positive DC input voltage Vi1+, and then passes through the first boost circuit to obtain a DC bus voltage Vbus, specifically including a positive bus voltage Vbus1+ of the positive bus and a negative bus voltage Vbus1- of the negative bus. Then, the output DC voltage and output DC current are obtained through the buck circuit. The output DC current includes a positive end current Iout1+ at the output positive end and a negative end current Iout1- at the output negative end, and the output DC voltage includes Vout+ and Vout-.

[0023] Specifically, the first boost circuit includes an input inductor and a switch tube s1, a first end of the input inductor is connected to a positive DC input voltage Vi1+, a second end of the input inductor is connected to a first end of the switch tube s1, and a second end of the switch tube s1 is connected to a negative DC input voltage Vi1-, current is collected at the second end of the input inductor to obtain an input inductor current IL1 of the first boost circuit, current is collected at the first end of the switch tube s1 to obtain a current Is1 flowing through the switch tube s1, an input capacitor is connected between the positive DC input voltage Vi1+ and the negative DC input voltage Vi1-; a first bus capacitor Cbus1 is connected between the positive bus and the negative bus, a first end of the first bus capacitor Cbus1 is connected to the positive bus, and a second end of the first bus capacitor Cbus1 is connected to the negative bus; and a first output capacitor Cout1 is connected between the output DC voltages Vout+ and Vout-, a first end of the first output capacitor Cout1 is connected to the output DC voltage Vout+, and a second end of the first output capacitor Cout1 is connected to the output DC voltage Vout-.

[0024] Among them, the second non-isolated power supply module includes a second three-phase rectifier circuit, a second boost circuit, a second buck circuit and a load connected in sequence. The second three-phase rectifier current controls and rectifies the A-phase current, B-phase current and C-phase current from the three-phase power grid through three-phase forward diodes Da2+, Db2+ and DC2+ respectively to obtain a positive DC input voltage Vi2+, and then passes through the second boost circuit to obtain a DC bus voltage Vbus, specifically including a positive bus voltage Vbus2+ of the positive bus and a negative bus voltage Vbus2- of the negative bus, and then passes through the buck circuit to obtain an output DC voltage and an output DC current, the output DC current includes a positive end current Iout2+ at the output positive end and a negative end current Iout2- at the output negative end, and the output DC voltage includes Vout+ and Vout-.

[0025] Specifically, the second boost circuit includes an input inductor and a switch tube s2, the second end of the input inductor is connected to the positive DC input voltage Vi2+, the second end of the input inductor is connected to the second end of the switch tube s2, the second end of the switch tube s2 is connected to the negative DC input voltage Vi2-, the input inductor current IL2 of the first boost circuit can be obtained by collecting current at the second end of the input inductor, and the current Is2 flowing through the switch tube s2 can be obtained by collecting current at the first end of the switch tube s2, an input capacitor is connected between the positive DC input voltage Vi2+ and the negative DC input voltage Vi2-; a second bus capacitor Cbus2 is connected between the positive bus and the negative bus, the second end of the second bus capacitor Cbus2 is connected to the positive bus, and the second end of the second bus capacitor Cbus2 is connected to the negative bus; and a second output capacitor Cout2 is connected between the output DC voltages Vout+ and Vout-, the second end of the second output capacitor Cout2 is connected to the output DC voltage Vout+, and the second end of the second output capacitor Cout2 is connected to the output DC voltage Vout-.

[0026] It can be understood that when the bus voltage of the first non-isolated power module is greater than the bus voltage of the second non-isolated power module, a circulating current will be generated when the two power modules work in parallel. The forward path of the circulating current is: positive bus Vbus1+, the positive output terminal of the first non-isolated power module, the positive output terminal of the second non-isolated power module, the positive bus Vbus2+, the second bus capacitor Cbus2, the negative bus Vbus2-, the negative DC input voltage Vi2-, the three-phase current A2 phase, B2 phase and C2 phase current obtained through the three-phase negative diodes Da2-, Db2- and DC2-, the input three-phase line, the three-phase negative diodes Da1-, Db1- and DC1-, the negative bus Vbus1-, the first bus capacitor Cbus1, and the positive bus Vbus1+.

[0027] It can be seen that in this embodiment, when the input ends of the two power modules are connected in parallel to the three-phase power grid and the output ends are connected in parallel to the load, due to the inconsistency of the bus voltage between the two power modules, a circulating current loop will be formed in which the high-voltage bus capacitor charges the low-voltage bus capacitor. Therefore, the circulating current suppression method proposed in the embodiment of the present application for determining the reference adjustment value of the bus voltage of each power module according to the current acquisition result can adjust the difference in bus voltages between different power modules to achieve dynamic balance, thereby avoiding as much as possible the situation where the bus voltage difference is too large and causing circulating current, which is beneficial to improving the safety and reliability of the power module.

[0028] See also Figure 2 , Figure 2 Schematic diagram of a parallel structure of non-isolated power modules connected to a three-phase AC source provided by an embodiment of the present application. Figure 2As shown, the input ends of the two non-isolated power modules are connected in parallel to a three-phase AC source, and the output ends are connected in parallel to a load.

[0029] Among them, each non-isolated power supply module includes a three-phase rectifier circuit, an input pre-stage filter capacitor, a first-stage non-isolated DC / DC circuit (i.e., a boost circuit), a bus capacitor, a second-stage non-isolated DC / DC circuit (i.e., a buck circuit), and an output capacitor.

[0030] Specifically, the A-phase, B-phase and C-phase currents from the three-phase AC source are rectified by a three-phase rectifier circuit to obtain input DC voltages Vin+ and Vin-, the first end of the input pre-stage filter is connected to the input DC voltage Vin+, and the second end of the input pre-stage filter is connected to the input DC voltage Vin-; then, bus voltages Vbus+ and Vbus- are obtained through a first-stage non-isolated DC / DC circuit; then, output DC voltages Vout+ and Vout- can be obtained through a second-stage non-isolated DC / DC circuit, a first output capacitor C1 is connected between the second-stage non-isolated DC / DC circuit of the first non-isolated power module and the output DC voltage, a first end of the first output capacitor C1 is connected to the output DC voltage Vout+, and a second end of the first output capacitor C1 is connected to the output DC voltage Vout-, and a second output capacitor C2 is connected between the second-stage non-isolated DC / DC circuit of the second non-isolated power module and the output DC voltage, a first end of the second output capacitor C2 is connected to the output DC voltage Vout+, and a second end of the second output capacitor C2 is connected to the output DC voltage Vout-.

[0031] It can be seen that in this embodiment, when multiple power modules are connected in parallel to a three-phase AC source, each power module needs to integrate the A-phase, B-phase and C-phase currents from the three-phase AC source through a three-phase rectifier current to obtain an input DC voltage, and then process the input DC voltage through a first-stage non-isolated DC / DC circuit to obtain a bus voltage, and then obtain an output voltage through a second-stage non-isolated DC / DC circuit; when multiple power modules are connected in parallel and synchronously perform voltage transformation processing, each power module will obtain a corresponding bus voltage, but due to different parameters and environmental factors in different periods in each power module, the bus voltage of each power module is inconsistent, so that the power module with a high bus voltage generates a current circulation to the power module with a low bus voltage. Therefore, the scheme for adjusting the bus voltage of each power module according to the current acquisition result provided in the embodiment of the present application can reduce the bus voltage difference and prevent current circulation.

[0032] See also Figure 3 , Figure 3 Schematic diagram of a parallel structure of non-isolated power modules connected to a DC source provided by an embodiment of the present application. Figure 3As shown, the input ends of the two non-isolated power modules are connected in parallel to a DC source, and the output ends are connected in parallel to a load.

[0033] Among them, each non-isolated power supply module includes an input pre-stage filter capacitor, a first-stage non-isolated DC / DC circuit (i.e., a boost circuit), a bus capacitor, a second-stage non-isolated DC / DC circuit (i.e., a buck circuit), and an output capacitor.

[0034] Specifically, input DC voltages Vin+ and Vin- are obtained according to a DC source, a first end of the input pre-stage filter is connected to the input DC voltage Vin+, and a second end of the input pre-stage filter is connected to the input DC voltage Vin-; then, bus voltages Vbus+ and Vbus- are obtained through a first-stage non-isolated DC / DC circuit; then, output DC voltages Vout+ and Vout- can be obtained through a second-stage non-isolated DC / DC circuit, a first output capacitor C1 is connected between the second-stage non-isolated DC / DC circuit of the first non-isolated power supply module and the output DC voltage, a first end of the first output capacitor C1 is connected to the output DC voltage Vout+, a second end of the first output capacitor C1 is connected to the output DC voltage Vout-, and a second output capacitor C2 is connected between the second-stage non-isolated DC / DC circuit of the second non-isolated power supply module and the output DC voltage, a first end of the second output capacitor C2 is connected to the output DC voltage Vout+, and a second end of the second output capacitor C2 is connected to the output DC voltage Vout-.

[0035] It can be seen that in this embodiment, when multiple power modules are connected in parallel to a DC source, an input DC voltage is obtained according to the DC source, and then the input DC voltage is processed by a first-level non-isolated DC / DC circuit to obtain a bus voltage, and then the output voltage is obtained through a second-level non-isolated DC / DC circuit; when multiple power modules are connected in parallel and synchronously perform voltage transformation processing, each power module will obtain a corresponding bus voltage, but due to different parameters and environmental factors in different periods in each power module, the bus voltage of each power module is inconsistent, so that the power module with a high bus voltage generates a current circulation to the power module with a low bus voltage. Therefore, the scheme for adjusting the bus voltage of each power module according to the current acquisition result provided in the embodiment of the present application can reduce the bus voltage difference, which is beneficial to prevent the occurrence of current circulation and improve the safety and reliability of the power module.

[0036] See also Figure 4 , Figure 4 This is a flowchart of a method for suppressing circulating current in parallel of a non-isolated power supply provided by an embodiment of the present application, which is applied to Figure 1 The controller of the DC / DC converter circuit shown in FIG. Figure 1 ,like Figure 4 As shown, the method comprises the following steps: Step S410, performing the following processing for each of the multiple non-isolated power modules, so that the difference between the two bus voltages corresponding to any two non-isolated power modules in the multiple non-isolated power modules is less than a preset difference.

[0037] In a possible embodiment, before performing the following processing on each of the multiple non-isolated power supply modules so that the difference between the two bus voltages corresponding to any two non-isolated power supply modules among the multiple non-isolated power supply modules is less than a preset difference, the method further includes: Determine a plurality of required bus voltage values ​​corresponding to the plurality of non-isolated power modules through a simulation model, wherein the required bus voltage value is a bus voltage value when the output power of each non-isolated power module reaches a maximum value under current operating parameters, and the operating parameters include input current, load current and temperature; Taking the maximum value among the multiple required bus voltage values ​​as the reference bus voltage given value; Determining a reference control signal for controlling a controlled device of a boost circuit in the plurality of non-isolated power modules according to the reference bus voltage given value; The reference control signal is sent to the controlled device of the boost circuit in the plurality of non-isolated power modules so that the plurality of DC buses of the plurality of non-isolated power modules have the same reference bus voltage given value.

[0038] The acquisition of the required bus voltage value and the selection of the reference bus voltage given value can be achieved through a master-slave module control algorithm.

[0039] Specifically, the master-slave module control algorithm can be to select one of the multiple power modules as the master module, and the other modules as slave modules. The master module and the slave modules communicate with each other through CAN. Each slave module sends its own required bus voltage value to the master module through CAN communication. After the master module receives the required bus voltage information of the slave module, it uses the highest required bus voltage value of all modules as a unified reference bus voltage given value, and sends it to multiple slave modules through CAN communication. Exemplarily, the master module and the slave module can be determined by arranging the production barcodes of multiple power modules, with the earliest produced module serving as the master module; and, when there is only one power module, the reference bus voltage given value is the required bus voltage value calculated by itself.

[0040] It can be seen that in this embodiment, before the anti-circulation operation is performed on each power module, the reference bus voltage setting of the remaining slave modules is controlled by the master module, so that multiple power modules have the same reference bus voltage setting value, thereby reducing the bus voltage difference between the power modules in the initial state of multiple power modules in parallel, which is beneficial to avoiding the generation of circulating current and reducing the degree of circulating current.

[0041] Step S420, obtaining a current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end.

[0042] In a possible embodiment, the boost circuit includes an input inductor and a switch tube connected in sequence, the controller adopts an average current control method to control the average value of the inductor current at the input end of the boost circuit in each switching cycle of the switch tube to be less than a preset value, the current acquisition circuit acquires the inductor current at the input end of the boost circuit by acquiring the current at the output end of the input inductor; the current acquisition circuit of the non-isolated power supply module currently being processed acquires the current acquisition result of the non-isolated power supply module, and the method further includes: Determining that the controller adopts a peak current control method to control the inductor current at the input end of the boost circuit to be less than a preset peak value; The reference current of the input end of the switch tube of the non-isolated power module is collected by the current collection circuit of the non-isolated power module being processed, so as to obtain the inductor current of the input end of the switch tube of the boost circuit of the non-isolated power module; The inductor current at the input end of the boost circuit of the non-isolated power module is obtained according to the ratio of the reference current to the duty cycle of the switch tube.

[0043] The positive terminal current of the positive output terminal and the negative terminal current of the negative output terminal of the buck circuit are directly acquired through a current acquisition circuit.

[0044] It can be understood that the inductor current at the input end of the boost circuit is the input inductor current of the non-isolated power supply module, and the input inductor current can be obtained by actual sampling or by conversion. When the loop is in average current control mode, that is, the average value of the input inductor current of the non-isolated power supply module in each switching cycle of the switch tube is controlled to be less than a preset value, the current at the output end of the input inductor is usually directly collected through a current collection circuit to obtain the input inductor current; and, when the loop is in peak current control mode, that is, the input inductor current is controlled to be less than a preset peak value, the current flowing through the switch tube is usually collected through a current collection circuit, and the ratio to the duty cycle at this time is calculated to obtain the input inductor current.

[0045] Specifically, Figure 1 As shown, when the loop is in average current control mode, the current at the output end of the input inductor is collected, and the input inductor current IL1 of the first non-isolated power module and the input inductor current IL2 of the second non-isolated power module can be directly obtained; and when the loop is in peak current control mode, the current Is1 at the input end of the switch tube s1 and the current Is2 at the input end of the switch tube s2 are collected respectively, and then the collected currents Is1 and Is2 are divided by the duty cycle D1 of the switch tube s1 and the duty cycle D2 of the switch tube s2 at this time, respectively, to obtain the input inductor currents IL1 and IL2 respectively.

[0046] It can be seen that in this embodiment, the input inductor current, output positive terminal current and output negative terminal current of each non-isolated power supply module in the multiple non-isolated power supply modules can be obtained through the current acquisition circuit, and the input inductor current can be obtained through actual sampling or conversion under different input inductor current control modes, so that the bus voltage can be further adjusted based on the current acquisition result to prevent current circulation, thereby indicating the safety and service life of the power supply module.

[0047] Step S430: determining a reference adjustment value of a bus voltage of a DC bus of the non-isolated power supply module according to the current acquisition result.

[0048] In a possible embodiment, the single non-isolated power supply module further includes a voltage acquisition circuit, the voltage acquisition circuit is connected to the DC bus, and the controller is connected to the voltage acquisition circuit; and determining a reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module according to the current acquisition result includes: The current bus voltage value of the DC bus of the non-isolated power module is collected by the voltage collection circuit of the non-isolated power module currently being processed to obtain the bus voltage value of the non-isolated power module; Determine the bus voltage adjustment value of the DC bus according to the product of the current acquisition result corresponding to the non-isolated power supply module and a preset proportionality coefficient, wherein the magnitude of the proportionality coefficient is positively correlated with the magnitude of the bus voltage adjustment value; A reference adjustment value of the bus voltage of the DC bus is determined according to the current bus voltage value of the DC bus of the non-isolated power supply module, the bus voltage adjustment value and the current acquisition result.

[0049] In a possible embodiment, determining the bus voltage adjustment value of the DC bus according to the product of the current acquisition result corresponding to the non-isolated power supply module and a preset proportionality coefficient includes: When the current acquisition result is the inductor current at the input end of the boost circuit, determining the first bus voltage adjustment value of the DC bus according to the product of the inductor current at the input end of the boost circuit and a preset first proportionality coefficient; and When the current acquisition result is the current at the output end of the buck circuit, the second bus voltage adjustment value of the DC bus is determined according to the product of the current difference between the positive end current of the positive output end of the buck circuit and the negative end current of the negative output end and a preset second proportional coefficient.

[0050] In a possible embodiment, determining a reference adjustment value of the bus voltage of the DC bus according to a current bus voltage value of the DC bus of the non-isolated power supply module, the bus voltage adjustment value, and the current acquisition result includes: When the current acquisition result is the inductor current of the input end of the boost circuit, determining whether the current acquisition result is greater than a preset current threshold; If it is determined that the current acquisition result is greater than the preset current threshold, determining a reference adjustment value of the bus voltage of the DC bus according to a difference between the bus voltage value and the first bus voltage adjustment value; and, If it is determined that the current acquisition result is not greater than the preset current threshold, determining a reference adjustment value of the bus voltage of the DC bus according to the sum of the bus voltage value and the first bus voltage adjustment value; When the current acquisition result is the current at the output end of the buck circuit, a reference adjustment value of the bus voltage of the DC bus is determined according to a difference between the bus voltage value and the second bus voltage adjustment value.

[0051] It is understandable that when the buses of multiple power modules are just connected together, the bus voltage difference between the modules is the largest, and the circulating current spike generated is the highest. Rapidly suppressing the circulating current spike at this time can greatly improve the reliability of the power module. When the positive output current increases, the output power increases, the input power also increases, the input inductor current increases, and vice versa, the input inductor current decreases. Therefore, the current bus voltage value can be adjusted according to the input inductor current. When the input inductor current is large, the bus voltage value is reduced, and when the input inductor current is small, the bus voltage value is increased to achieve dynamic circulating current spike suppression.

[0052] It is understandable that due to the differences in components between different power modules, even if the same reference bus voltage setpoint is set, the actual bus voltage value of each power module may not be completely consistent, resulting in circulating current, so the bus voltage of each power module needs to be adjusted separately. The bus voltage adjustment algorithm can be combined with the steady-state output current to adjust the bus voltage by detecting the positive and negative currents of the module.

[0053] Specifically, in theory, when no circulating current is generated, the positive terminal current and the negative terminal current of the module are consistent. When there is a circulating current, the circulating current will be superimposed on the positive terminal current. When the positive terminal current of the module is greater than the negative terminal current, it means that the actual bus voltage of the module is higher than that of other modules, and the current direction is flowing out of this module. When the positive terminal current of the module is less than the negative terminal current, it means that the actual bus voltage of the module is lower than that of other modules, and the current direction is flowing into this module. Therefore, the difference between the positive terminal current and the negative terminal current can be used as the basis for the reference adjustment value of the bus voltage. When the positive terminal current is higher than the negative terminal current, the current bus voltage value is reduced, otherwise it is increased, thereby achieving bus voltage balance control in steady state.

[0054] Furthermore, due to the detection of the positive and negative currents of the power module itself and the calculation of the new bus voltage reference adjustment value, a certain time delay will be generated. In particular, when a two-stage or multi-stage topology is used, the positive and negative currents are detected on the output side, and the bus voltage is adjusted on the input side. There is a communication delay between the output side and the input side, so only slow bus voltage adjustment can be achieved in a steady state.

[0055] It can be seen that in this embodiment, after setting a consistent reference bus voltage set value for all modules, each module then adjusts the bus voltage according to its own positive and negative current difference to achieve slow steady-state circulating current regulation, and controls the bus voltage droop by inputting the inductor current, thereby achieving rapid suppression of dynamic circulating current spikes.

[0056] Step S440: determining a control signal for controlling a controlled device of a boost circuit in the non-isolated power module according to the reference adjustment value, wherein the controlled device includes a PWM controller.

[0057] Step S450: sending the control signal to the controlled device of the boost circuit in the non-isolated power module.

[0058] It can be seen that in the embodiment of the present application, the controlled device mainly includes a PWM controller, which adjusts the duty cycle of the switch tube in the boost circuit according to the control signal to adjust the output voltage value of the boost circuit, thereby changing the bus voltage value, so that the bus voltage value can be changed to a reference adjustment value, thereby reducing the bus voltage difference between multiple power modules, which is beneficial to prevent the occurrence of circulating current.

[0059] Step S460: It is detected that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is smaller than the preset difference.

[0060] In a possible embodiment, when it is detected that the difference between the two bus voltages corresponding to any two non-isolated power supply modules among the plurality of non-isolated power supply modules is less than the preset difference, the method further includes: It is detected that the difference between the two bus voltages corresponding to two non-isolated power supply modules among the multiple non-isolated power supply modules is greater than or equal to the preset difference; The following process is performed for each of the plurality of non-isolated power supply modules: Acquire a second current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the second current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end; Determine a second reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module according to the second current acquisition result; Determining a second control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the second reference adjustment value, wherein the controlled device includes a PWM controller; Sending the second control signal to the controlled device of the boost circuit in the non-isolated power supply module; It is detected that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is smaller than the preset difference.

[0061] It can be seen that in the embodiment of the present application, after the bus voltage of each non-isolated power supply module in a plurality of non-isolated power supply modules is adjusted, if it is still detected that the difference between the two bus voltages corresponding to two non-isolated power supply modules is greater than or equal to the preset difference, it means that there is still circulating current. The reason why there is still circulating current may be due to environmental changes, such as temperature, humidity, etc., there are large differences in the components of the power supply modules, etc., then the bus voltage value of each power supply module is continued to be adjusted according to the input inductor current, output positive terminal current and output negative terminal current of each power supply module, until the difference between the two bus voltages corresponding to any two non-isolated power supply modules is less than the preset difference, thereby achieving circulating current suppression in steady state and dynamic state, which is beneficial to improving the safety and reliability of the power supply module.

[0062] See also Figure 5 , Figure 5 The present invention provides a method for suppressing the circulating current of a non-isolated power supply in parallel. Figure 1 The DC / DC converter circuit shown in the figure is combined with Figure 1 ,like Figure 5As shown, the non-isolated power supply parallel circulating current suppression method includes the following steps: (1) the power module input is powered on. (2) After each T0 time, whether a program interrupt is triggered. Specifically, if the program interrupt is triggered, step (3) is executed, otherwise step (6) is executed. The execution cycle of the interrupt program is generally at the us level, which can respond quickly. (3) The inductor current I at the output end of the current input inductor is sampled in real time. The inductor current I can be converted from other sampled currents. (4) After T1 time or more, whether the bus voltage setting is not changed in the interrupt program. Specifically, if the bus voltage setting is not changed, step (5) is executed, otherwise step (13) is executed. The T1 time can be adjusted according to actual conditions. During the T1 time, the bus voltage changes from the reference bus voltage setting value to the actual bus voltage value. (5) The bus voltage adjustment value △VbusComp1 =I×k1, and the reference adjustment value of the bus voltage is the current bus voltage value minus △VbusComp1. The value of the ratio k1 can be adjusted according to actual conditions. (6) Whether time T2 has passed. Specifically, if time T2 has passed, step (7) is executed, otherwise step (9) is executed. The time T2 can be adjusted according to actual conditions. During the time T2, the bus voltage changes from the reference bus voltage given value to the actual bus voltage value. (7) Sample the positive output current Ipos and negative output current Ineg of the current buck circuit. (8) Current difference △I = Ipos – Ineg, bus voltage adjustment value △VbusComp2 = △I × k2, and the reference adjustment value of the bus voltage is the current bus voltage value minus △VbusComp2. The value of ratio k2 can be adjusted according to actual conditions. (9) Whether time T3 has passed. Specifically, if time T3 has passed, step (10) is executed, otherwise step (13) is executed. The time T3 can be adjusted according to actual conditions. During the time T3, multiple non-isolated power modules perform CAN communication and parse data. T2 is greater than T3. (10) Whether there is only one power module, or whether the power module is the main module. If so, execute step (11), otherwise execute step (12). The determination method of the master module and the slave module is not limited. For example, they can be arranged according to the module production barcode, and the earliest produced module is used as the master module. (11) The maximum bus demand value of all modules is used as the reference bus voltage given value, and it is sent to the slave module through CAN communication. When there is only one module, the reference bus voltage given value is the bus demand value calculated by itself. (12) Send its own bus demand value to the master module through CAN communication, and receive the reference bus voltage given value from the master module. (13) The circulating current suppression strategy ends.

[0063] It can be seen that in this embodiment, at time T3, a unified reference bus voltage set value is first set for multiple non-isolated power modules through the master-slave module control algorithm, and then at time T0 when no interrupt program is performed, after T2 time has passed, the bus voltage of each module is adjusted according to the current difference between the output positive terminal current and the output negative terminal current of each non-isolated power module, and after the interrupt program is performed, after T1 time has passed, the bus voltage of each module is adjusted according to the input inductor current of each non-isolated power module, thereby achieving circulating current suppression in dynamic and steady states respectively, which is beneficial to improving the reliability and safety of the power module.

[0064] See also Figure 6 , Figure 6 : is a functional unit block diagram of a non-isolated power supply parallel circulating current suppression device 600 provided in an embodiment of the present application. The non-isolated power supply parallel circulating current suppression device 600 is applied to Figure 1 The DC / DC converter circuit shown in the figure is combined with Figure 1 ,like Figure 6 As shown, the non-isolated power supply parallel circulating current suppression device 600 includes the following units: The processing unit 610 is used to perform the following processing on each of the multiple non-isolated power supply modules, so that the difference between the two bus voltages corresponding to any two non-isolated power supply modules among the multiple non-isolated power supply modules is less than a preset difference; The acquisition unit 620 is used to acquire a current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end; A first determining unit 630, configured to determine a reference adjustment value of a bus voltage of a DC bus of the non-isolated power supply module according to the current acquisition result; A second determining unit 640 is used to determine a control signal for controlling a controlled device of a boost circuit in the non-isolated power module according to the reference adjustment value, wherein the controlled device includes a PWM controller; A sending unit 650, configured to send the control signal to the controlled device of the boost circuit in the non-isolated power module; The detection unit 660 is used to detect that the difference between the two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is less than the preset difference.

[0065] In one embodiment, the single non-isolated power supply module further includes a voltage acquisition circuit, the voltage acquisition circuit is connected to the DC bus, and the controller is connected to the voltage acquisition circuit; the reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module is determined according to the current acquisition result, including: The current bus voltage value of the DC bus of the non-isolated power module is collected by the voltage collection circuit of the non-isolated power module currently being processed to obtain the bus voltage value of the non-isolated power module; Determine the bus voltage adjustment value of the DC bus according to the product of the current collection result corresponding to the non-isolated power supply module and a preset proportionality coefficient, wherein the magnitude of the proportionality coefficient is positively correlated with the magnitude of the bus voltage adjustment value; A reference adjustment value of the bus voltage of the DC bus is determined according to the current bus voltage value of the DC bus of the non-isolated power supply module, the bus voltage adjustment value and the current acquisition result.

[0066] In one embodiment, determining the bus voltage adjustment value of the DC bus according to the product of the current acquisition result corresponding to the non-isolated power supply module and a preset proportionality coefficient includes: When the current acquisition result is the inductor current at the input end of the boost circuit, determining the first bus voltage adjustment value of the DC bus according to the product of the inductor current at the input end of the boost circuit and a preset first proportionality coefficient; and When the current acquisition result is the current at the output end of the buck circuit, the second bus voltage adjustment value of the DC bus is determined according to the product of the current difference between the positive end current of the positive output end of the buck circuit and the negative end current of the negative output end and a preset second proportional coefficient.

[0067] In one embodiment, determining a reference adjustment value of the bus voltage of the DC bus according to the current bus voltage value of the DC bus of the non-isolated power supply module, the bus voltage adjustment value and the current acquisition result includes: When the current acquisition result is the inductor current of the input end of the boost circuit, determining whether the current acquisition result is greater than a preset current threshold; If it is determined that the current acquisition result is greater than the preset current threshold, determining a reference adjustment value of the bus voltage of the DC bus according to a difference between the bus voltage value and the first bus voltage adjustment value; and, If it is determined that the current acquisition result is not greater than the preset current threshold, determining a reference adjustment value of the bus voltage of the DC bus according to the sum of the bus voltage value and the first bus voltage adjustment value; When the current acquisition result is the current at the output end of the buck circuit, a reference adjustment value of the bus voltage of the DC bus is determined according to a difference between the bus voltage value and the second bus voltage adjustment value.

[0068] In one embodiment, the boost circuit includes an input inductor and a switch tube connected in sequence, the controller uses an average current control method to control the average value of the inductor current at the input end of the boost circuit in each switching cycle of the switch tube to be less than a preset value, the current acquisition circuit acquires the inductor current at the input end of the boost circuit by acquiring the current at the output end of the input inductor; the current acquisition circuit of the non-isolated power supply module currently being processed acquires the current acquisition result of the non-isolated power supply module, and the method further includes: Determining that the controller adopts a peak current control method to control the inductor current at the input end of the boost circuit to be less than a preset peak value; The reference current of the input end of the switch tube of the non-isolated power module is collected by the current collection circuit of the non-isolated power module being processed, so as to obtain the inductor current of the input end of the switch tube of the boost circuit of the non-isolated power module; The inductor current at the input end of the boost circuit of the non-isolated power module is obtained according to the ratio of the reference current to the duty cycle of the switch tube.

[0069] In one embodiment, when it is detected that the difference between the two bus voltages corresponding to any two non-isolated power modules among the plurality of non-isolated power modules is less than the preset difference, the method further comprises: It is detected that the difference between the two bus voltages corresponding to two non-isolated power supply modules among the multiple non-isolated power supply modules is greater than or equal to the preset difference; The following process is performed for each of the plurality of non-isolated power supply modules: Acquire a second current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the second current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end; Determine a second reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module according to the second current acquisition result; Determining a second control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the second reference adjustment value, wherein the controlled device includes a PWM controller; Sending the second control signal to the controlled device of the boost circuit in the non-isolated power supply module; It is detected that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is smaller than the preset difference.

[0070] In one embodiment, before performing the following processing on each of the plurality of non-isolated power supply modules so that the difference between the two bus voltages corresponding to any two non-isolated power supply modules among the plurality of non-isolated power supply modules is less than a preset difference, the method further includes: Determine a plurality of required bus voltage values ​​corresponding to the plurality of non-isolated power modules through a simulation model, wherein the required bus voltage value is a bus voltage value when the output power of each non-isolated power module reaches a maximum value under current operating parameters, and the operating parameters include input current, load current and temperature; Taking the maximum value among the multiple required bus voltage values ​​as the reference bus voltage given value; Determining a reference control signal for controlling a controlled device of a boost circuit in the plurality of non-isolated power modules according to the reference bus voltage given value; The reference control signal is sent to the controlled device of the boost circuit in the plurality of non-isolated power modules so that the plurality of DC buses of the plurality of non-isolated power modules have the same reference bus voltage given value.

[0071] It can be understood that since the method embodiment and the device embodiment are different presentation forms of the same technical concept, the content of the method embodiment part in this application should be synchronously adapted to the device embodiment part and will not be repeated here.

[0072] It can be seen that the non-isolated power supply parallel circulating current suppression device 600 performs the following processing for each non-isolated power supply module in a plurality of non-isolated power supply modules through the processing unit 610; then, the current collection result of the non-isolated power supply module is obtained through the current collection circuit of the non-isolated power supply module currently being processed through the collection unit 620; then, the reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module is determined according to the current collection result through the first determination unit 630; secondly, the control signal for controlling the controlled device of the boost circuit in the non-isolated power supply module is determined according to the reference adjustment value through the second determination unit 640; again, the control signal is sent to the controlled device of the boost circuit in the non-isolated power supply module through the sending unit 650; finally, the difference between the two bus voltages corresponding to any two non-isolated power supply modules in the plurality of non-isolated power supply modules is detected by the detection unit 660 to be less than the preset difference. The circulating current suppression and bus voltage of the balancing module under all working conditions are realized, and the product reliability and service life are improved.

[0073] See also Figure 7 , Figure 7 is a structural block diagram of an electronic device provided in an embodiment of the present application, such as Figure 7 As shown, the electronic device 700 may include one or more of the following components: a processor 710, and a memory 720 coupled to the processor 710, wherein the memory 720 may store one or more computer programs, and the one or more computer programs may be configured to implement the methods described in the above embodiments when executed by one or more processors 710.

[0074] The processor 710 may include one or more processing cores. The processor 710 uses various interfaces and lines to connect various parts of the entire electronic device 700, and executes various functions and processes data of the electronic device 700 by running or executing instructions, programs, code sets or instruction sets stored in the memory 720, and calling data stored in the memory 720. Optionally, the processor 710 can be implemented in at least one hardware form of digital signal processing (DSP), field-programmable gate array (FPGA), and programmable logic array (PLA). The processor 710 can integrate one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. 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 modem may not be integrated into the processor 710, but may be implemented separately through a communication chip.

[0075] The memory 720 may include a random access memory (RAM) or a read-only memory (ROM). The memory 720 may be used to store instructions, programs, codes, code sets or instruction sets. The memory 720 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 (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc. The data storage area may also store data created by the electronic device 700 during use, etc.

[0076] It is understandable that the electronic device 700 may include more or fewer structural elements than those in the above structural block diagram, for example, a power module, physical buttons, a Wi-Fi module, a speaker, a Bluetooth module, a sensor, etc., which are not limited here.

[0077] In addition, an embodiment of the present application also provides a computer storage medium, which stores a computer program that can be loaded by a processor and executed such as the above-mentioned method for suppressing parallel circulating current of a non-isolated power supply. The computer-readable storage medium includes, for example: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0078] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0079] In the several embodiments provided in the present application, it should be understood that the disclosed methods, devices and systems can be implemented in other ways. For example, the device embodiments described above are only schematic; for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation; for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, the functional units in various embodiments of the present invention can be integrated into a processing unit, or each unit can be physically included separately, or two or more units can be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of hardware plus software functional units.

[0080] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform some steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a volatile memory or a non-volatile memory. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of random access memory (RAM) are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM) and direct memory bus random access memory (DRRAM), etc., various media that can store program code.

[0081] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0082] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

[0083] Although the present application is disclosed as above, the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions without departing from the spirit and scope of the present application, and can make various changes and modifications, including the combination of the above-mentioned different functions and implementation steps, including software and hardware implementation methods, all of which are within the scope of protection of the present application.

Claims

1. A method for suppressing circulating current in parallel of a non-isolated power supply, characterized in that: A controller applied to a DC / DC conversion circuit, wherein the DC / DC conversion circuit comprises a three-phase current source, a plurality of non-isolated power supply modules connected in parallel, and a load, wherein the plurality of non-isolated power supply modules are respectively connected to the three-phase current source and the load; a single non-isolated power supply module comprises a three-phase rectifier circuit, a current acquisition circuit, a boost circuit, and a buck circuit, wherein the controller is respectively connected to the current acquisition circuit and the boost circuit, wherein the boost circuit is connected to the buck circuit via a DC bus, wherein the current acquisition circuit is connected to an input end of the boost circuit, and wherein the current acquisition circuit is respectively connected to a positive output end and a negative output end of the buck circuit; wherein the method comprises: Performing the following processing for each of the multiple non-isolated power supply modules, so that the difference between the two bus voltages corresponding to any two non-isolated power supply modules of the multiple non-isolated power supply modules is less than a preset difference; Acquire a current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end; Determine a reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module according to the current acquisition result; Determining a control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the reference adjustment value, wherein the controlled device includes a PWM controller; Sending the control signal to the controlled device of the boost circuit in the non-isolated power module; It is detected that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is smaller than the preset difference.

2. The method according to claim 1, characterized in that The single non-isolated power supply module further includes a voltage acquisition circuit, the voltage acquisition circuit is connected to the DC bus, and the controller is connected to the voltage acquisition circuit; the reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module is determined according to the current acquisition result, including: The current bus voltage value of the DC bus of the non-isolated power module is collected by the voltage collection circuit of the non-isolated power module currently being processed to obtain the bus voltage value of the non-isolated power module; Determine the bus voltage adjustment value of the DC bus according to the product of the current collection result corresponding to the non-isolated power supply module and a preset proportionality coefficient, wherein the magnitude of the proportionality coefficient is positively correlated with the magnitude of the bus voltage adjustment value; A reference adjustment value of the bus voltage of the DC bus is determined according to the current bus voltage value of the DC bus of the non-isolated power supply module, the bus voltage adjustment value and the current acquisition result.

3. The method according to claim 2, characterized in that The determining the bus voltage adjustment value of the DC bus according to the product of the current acquisition result corresponding to the non-isolated power supply module and a preset proportionality coefficient includes: When the current acquisition result is the inductor current at the input end of the boost circuit, determining the first bus voltage adjustment value of the DC bus according to the product of the inductor current at the input end of the boost circuit and a preset first proportionality coefficient; and When the current acquisition result is the current at the output end of the buck circuit, the second bus voltage adjustment value of the DC bus is determined according to the product of the current difference between the positive end current of the positive output end of the buck circuit and the negative end current of the negative output end and a preset second proportional coefficient.

4. The method according to claim 3, characterized in that The step of determining a reference adjustment value of the bus voltage of the DC bus according to the current bus voltage value of the DC bus of the non-isolated power supply module, the bus voltage adjustment value and the current acquisition result includes: When the current acquisition result is the inductor current of the input end of the boost circuit, determining whether the current acquisition result is greater than a preset current threshold; If it is determined that the current acquisition result is greater than the preset current threshold, determining a reference adjustment value of the bus voltage of the DC bus according to a difference between the bus voltage value and the first bus voltage adjustment value; and, If it is determined that the current acquisition result is not greater than the preset current threshold, determining a reference adjustment value of the bus voltage of the DC bus according to the sum of the bus voltage value and the first bus voltage adjustment value; When the current acquisition result is the current at the output end of the buck circuit, a reference adjustment value of the bus voltage of the DC bus is determined according to a difference between the bus voltage value and the second bus voltage adjustment value.

5. The method according to claim 4, characterized in that The boost circuit includes an input inductor and a switch tube connected in sequence, the controller uses an average current control method to control the average value of the inductor current at the input end of the boost circuit in each switching cycle of the switch tube to be less than a preset value, and the current acquisition circuit acquires the inductor current at the input end of the boost circuit by acquiring the current at the output end of the input inductor; The current acquisition result of the non-isolated power supply module is obtained by using the current acquisition circuit of the non-isolated power supply module currently being processed, and the method further includes: Determining that the controller adopts a peak current control method to control the inductor current at the input end of the boost circuit to be less than a preset peak value; The reference current of the input end of the switch tube of the non-isolated power module is collected by the current collection circuit of the non-isolated power module being processed, so as to obtain the inductor current of the input end of the switch tube of the boost circuit of the non-isolated power module; The inductor current at the input end of the boost circuit of the non-isolated power module is obtained according to the ratio of the reference current to the duty cycle of the switch tube.

6. The method according to claim 5, characterized in that The method further comprises: detecting that a difference between two bus voltages corresponding to any two non-isolated power supply modules among the plurality of non-isolated power supply modules is less than a preset difference; It is detected that the difference between the two bus voltages corresponding to two non-isolated power supply modules among the multiple non-isolated power supply modules is greater than or equal to the preset difference; The following process is performed for each of the plurality of non-isolated power supply modules: Acquire a second current acquisition result of the non-isolated power supply module through the current acquisition circuit of the non-isolated power supply module currently being processed, wherein the second current acquisition result includes the inductor current at the input end of the boost circuit or the current at the output end of the buck circuit, and the current at the output end of the buck circuit includes the positive end current of the positive output end and the negative end current of the negative output end; Determine a second reference adjustment value of the bus voltage of the DC bus of the non-isolated power supply module according to the second current acquisition result; Determining a second control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the second reference adjustment value, wherein the controlled device includes a PWM controller; Sending the second control signal to the controlled device of the boost circuit in the non-isolated power supply module; It is detected that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is smaller than the preset difference.

7. The method according to any one of claims 1 to 6, characterized in that: Before performing the following processing on each of the plurality of non-isolated power supply modules so that the difference between the two bus voltages corresponding to any two non-isolated power supply modules among the plurality of non-isolated power supply modules is less than a preset difference, the method further includes: Determine a plurality of required bus voltage values ​​corresponding to the plurality of non-isolated power modules through a simulation model, wherein the required bus voltage value is a bus voltage value when the output power of each non-isolated power module reaches a maximum value under current operating parameters, and the operating parameters include input current, load current and temperature; Taking the maximum value among the multiple required bus voltage values ​​as the reference bus voltage given value; Determining a reference control signal for controlling a controlled device of a boost circuit in the plurality of non-isolated power modules according to the reference bus voltage given value; The reference control signal is sent to the controlled device of the boost circuit in the plurality of non-isolated power modules so that the plurality of DC buses of the plurality of non-isolated power modules have the same reference bus voltage given value.

8. A non-isolated power supply parallel circulating current suppression device, characterized in that: A controller applied to a DC / DC conversion circuit, wherein the DC / DC conversion circuit comprises a three-phase current source, a plurality of non-isolated power supply modules connected in parallel, and a load, wherein the plurality of non-isolated power supply modules are respectively connected to the three-phase current source and the load; a single non-isolated power supply module comprises a three-phase rectifier circuit, a current acquisition circuit, a boost circuit, and a buck circuit, wherein the controller is respectively connected to the current acquisition circuit and the boost circuit, wherein the boost circuit is connected to the buck circuit via a DC bus, wherein the current acquisition circuit is connected to an input end of the boost circuit, and wherein the current acquisition circuit is respectively connected to a positive output end and a negative output end of the buck circuit; wherein the device comprises: A processing unit, configured to perform the following processing on each of the plurality of non-isolated power supply modules, so that a difference between two bus voltages corresponding to any two non-isolated power supply modules of the plurality of non-isolated power supply modules is less than a preset difference; A collection unit, used for acquiring a current collection result of the non-isolated power supply module through a current collection circuit of the non-isolated power supply module currently being processed, wherein the current collection result includes an inductor current at an input end of the boost circuit or a current at an output end of the buck circuit, and the current at the output end of the buck circuit includes a positive end current of the positive output end and a negative end current of the negative output end; A first determining unit, configured to determine a reference adjustment value of a bus voltage of a DC bus of the non-isolated power supply module according to the current acquisition result; A second determining unit, configured to determine a control signal for controlling a controlled device of a boost circuit in the non-isolated power supply module according to the reference adjustment value, wherein the controlled device includes a PWM controller; A sending unit, configured to send the control signal to the controlled device of the boost circuit in the non-isolated power supply module; The detection unit is used to detect that the difference between two bus voltages corresponding to any two non-isolated power modules among the multiple non-isolated power modules is less than the preset difference.

9. An electronic device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: The computer program / instructions are executed by a processor to implement the steps of the method according to any one of claims 1 to 7.

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