A power converter and power supply device

Abstract

This utility model relates to the field of power electronic conversion technology, and in particular to a power converter and power supply device. This utility model replaces the independent synchronization signal line and current sharing bus in traditional solutions by dynamically transmitting initialization synchronization signals or voltage feedback signals on a single time-division multiplexing bus. This avoids the linear increase in wiring complexity caused by the increase in the number of power converters, significantly reducing system complexity and hardware costs. Furthermore, reducing the number of signal lines can reduce hardware costs; reducing the number of single signal lines lowers system costs by approximately 5%-15%. Simultaneously, in high-density installation scenarios, wiring management costs can be reduced by more than 20%, significantly improving system economy.

Description

Technical Field

[0001] This utility model relates to the field of power electronic conversion technology, and in particular to a power converter and power supply device. Background Technology

[0002] In the common architecture of parallel power supply for multiple power converters, traditional technical solutions typically rely on independent signal lines to perform two key tasks: synchronous startup and current sharing control of the multiple power converters. For synchronous startup, a synchronization signal line is often used to ensure that each power converter starts up synchronously and outputs its supply voltage simultaneously. This method requires each power converter to have its own synchronization signal line to transmit its initialization status and ensure simultaneous startup. For current sharing control, a current sharing bus is used to transmit current distribution information to achieve active current sharing. This method also requires each power converter to have its own current sharing bus to transmit its current status and ensure that the current of multiple power converters tends to be consistent.

[0003] As the number of power converters continues to increase, the number of synchronization signal lines and current sharing buses required also increases, resulting in a significant linear increase in wiring complexity. This not only substantially increases hardware costs (system costs increase by approximately 5%-15% for each additional signal line), but also raises the risk of system failures due to the increased wiring (cable failure rates increase exponentially with the number of cables). Furthermore, in actual installation and maintenance, the complex wiring makes troubleshooting extremely difficult, especially in high-density installation environments where wiring management costs can account for more than 20% of the total system cost.

[0004] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Utility Model Content

[0005] The technical problem this invention aims to solve is how to adjust the power converter to reduce the number of synchronization signal lines and current sharing buses in a multi-power converter parallel power supply device, thereby reducing wiring complexity.

[0006] The present invention adopts the following technical solution:

[0007] In a first aspect, a power converter is provided for use in a power supply device with multiple power converters connected in parallel, the power converter including a control module connected to a time-division multiplexing bus.

[0008] The control module is used to send initialization synchronization signals and voltage feedback signals to the time-division multiplexing bus, and to collect the signal status on the time-division multiplexing bus; the time-division multiplexing bus is used to transmit initialization synchronization signals and voltage feedback signals of different power converters.

[0009] Preferably, the power converter further includes a switching module, the control module is connected to one end of the switching module, and the other end of the switching module is connected to the time-division multiplexing bus;

[0010] The switching module is used to selectively transmit the initialization synchronization signal or the voltage feedback signal to the time-division multiplexing bus at different times.

[0011] Preferably, the switching module includes a co-start isolation unit and a current sharing isolation unit; both the co-start isolation unit and the current sharing isolation unit are multi-channel selection switches, wherein the multi-channel selection switch includes at least two selection channels.

[0012] Preferably, the IO1 port of the control module is connected to the control terminal of the simultaneous start isolation unit; the IO3 port of the control module is connected to the time-division multiplexing bus, the time-division multiplexing bus is connected to the common terminal on the simultaneous start isolation unit, the IO2 port of the control module is connected to the first switching terminal on the simultaneous start isolation unit, and the second switching terminal on the simultaneous start isolation unit is left unconnected; the simultaneous start isolation unit is used to transmit the initialization synchronization signal to the time-division multiplexing bus at different times.

[0013] Preferably, the IO4 port of the control module is connected to the control terminal of the current sharing isolation unit; the ADC port of the control module is connected to the time-division multiplexing bus, the time-division multiplexing bus is connected to the common terminal on the current sharing isolation unit, the DAC port of the control module is connected to the first switching terminal on the current sharing isolation unit, and the second switching terminal on the current sharing isolation unit is disconnected; the current sharing isolation unit is used to transmit the voltage feedback signal to the time-division multiplexing bus at different times.

[0014] Preferably, the co-start isolation unit and the current sharing isolation unit are integrated into one module.

[0015] Preferably, the switching module is model TPW3223.

[0016] Preferably, the co-start isolation unit and the current sharing isolation unit are both independent switching units.

[0017] Preferably, the control module is an STM32H743VIT6 or a DSPIC33.

[0018] In a second aspect, a power supply device is provided, comprising at least two power converters as described in the first aspect and a time-division multiplexing bus, wherein at least two of the power converters are connected to the time-division multiplexing bus.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0020] This invention dynamically transmits initialization synchronization signals or voltage feedback signals on a single time-division multiplexing bus, replacing the independent synchronization signal line and current sharing bus in traditional solutions. This avoids the linear increase in wiring complexity caused by the increase in the number of power converters, significantly reducing system complexity and hardware costs. Furthermore, reducing the number of signal lines can reduce hardware costs; reducing the number of single signal lines reduces system costs by approximately 5%-15%. At the same time, in high-density installation scenarios, wiring management costs can be reduced by more than 20%, significantly improving system economy. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1a This is a schematic diagram of the structure of a power converter provided in an embodiment of this utility model;

[0023] Figure 1 This is a schematic diagram of another power converter provided in this embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of a power supply device with multiple power converters provided in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of another power supply device with multiple power converters provided in this embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of another power converter provided in this embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of another power supply device with multiple power converters provided in this embodiment of the utility model;

[0028] Figure 6 This is a schematic diagram of the state of each signal in a time-division multiplexing control method provided by an embodiment of this utility model;

[0029] Figure 7 This is a schematic diagram of the synchronous start-up stage of a power supply device provided in an embodiment of this utility model;

[0030] Figure 8 This is a schematic diagram of the passive current sharing stage of a power supply device provided in an embodiment of the present invention;

[0031] Figure 9 This is a schematic diagram of the active current sharing stage of a power supply device provided in an embodiment of the present utility model;

[0032] Figure 10 This is a schematic diagram of the structure of a power supply device after stabilization, provided in an embodiment of this utility model;

[0033] Figure 11 This is a flowchart illustrating a time-division multiplexing control method provided in an embodiment of this utility model. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0035] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as openly inclusive, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples; that is, although they may be incorporated into embodiments or examples using the above terms for reasons such as order and position, it does not limit them to be incorporated in combination by a single embodiment or example.

[0036] In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more. Furthermore, for example, the description may use the prefix "A" or "B" to describe the same type of nouns as two independent entities. In this case, the features defined with "A" and "B" are used only to distinguish between similar entities and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features.

[0037] In describing some embodiments, the terms "coupled," "coupled," and "connected," and their derivative expressions, may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact with each other. Similarly, the term "coupled" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact. However, the terms "connected" or "coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other, such as "optical coupling" or "wireless connection." The embodiments disclosed herein are not necessarily limited to the scope of this invention.

[0038] Furthermore, the technical features involved in the various embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0039] Example 1:

[0040] When multiple power converters are connected in parallel and powered on, the initialization time of each power converter's internal microcontroller (MCU) varies considerably (typically by 1µs to 50ms). This difference directly leads to inconsistent start-up times for the output voltages of each power converter. This asynchronous startup phenomenon will trigger inrush current problems, causing the power module to activate overcurrent protection. Actual tests and related research data show that the peak value of the inrush current can reach up to three times the rated output current. Such a powerful instantaneous current surge can easily cause irreversible damage to power devices (e.g., an increase of more than 20% in the on-resistance of MOSFETs), thus affecting the reliability and lifespan of the entire system. For example, in the power supply system of server equipment, such inrush currents will interfere with the delicate electronic components of the equipment, even causing equipment failure and affecting the normal operation of the server; in the aerospace field, it will cause the power bus voltage to collapse, leading to the failure of critical loads. Therefore, in practical applications, it is necessary to ensure that multiple power converters start simultaneously. Current technology uses synchronized signal lines to determine the initialization completion time of each power converter, and then starts all power converters simultaneously after they have all completed initialization. However, as the number of power converters continues to increase, the number of synchronized signal lines required also increases, increasing wiring complexity.

[0041] Furthermore, power converters also need to ensure consistent current. In practical applications, passive and active current sharing techniques are generally used to regulate the current of the power converter, making the current more consistent. Passive current sharing technology has the significant advantage of extremely fast response speed, typically reacting to current changes in the microsecond range. However, passive current sharing accuracy is relatively low, with significant deviations in the output current of each power converter, which cannot meet the stringent current accuracy requirements of applications such as medical equipment (requiring current sharing accuracy of ±1% or less) and aerospace (requiring ±0.5% or less). While active current sharing technology can improve current sharing accuracy to a high level of ±1%, its reliance on real-time communication to obtain current information from each power converter and coordinate control inevitably leads to a slower dynamic response speed, typically in the millisecond range. In situations requiring rapid response to current changes, such as the instantaneous high power demands of some industrial equipment, this delay will adversely affect the stable operation of the equipment and may even cause system oscillations. In order to make the current more uniform, a current sharing bus needs to be designed. However, as the number of power converters continues to increase, the number of current sharing buses that need to be laid also increases, increasing the wiring complexity.

[0042] To address the issue of complex wiring caused by the need to set up different signal lines separately for synchronous startup and current sharing in existing technologies, this embodiment proposes two types of power converters to solve this problem.

[0043] First, we introduce the first type of power converter. In one embodiment, such as... Figure 1a As shown, the power converter is used in a power supply device with multiple power converters connected in parallel. The power converter includes a control unit, a startup synchronization unit, and a current balancing unit. The startup synchronization unit and the current balancing unit are respectively connected to the control unit. The startup synchronization unit, the current balancing unit, and the control unit are respectively connected to a time-sharing multiplexing bus (i.e., Share Bus). During the initialization of the power converter, the startup synchronization unit outputs initialization synchronization signals of different levels according to the initialization status of the power converter. The control unit continuously samples the initialization synchronization signals on the time-sharing multiplexing bus. When an initialization synchronization signal of a preset level is detected on the time-sharing multiplexing bus, the control unit outputs a startup synchronization signal to the startup synchronization unit and the current balancing unit. The startup synchronization unit controls the startup of the corresponding power converter according to the startup synchronization signal. The current balancing unit performs current sharing control on the power converters according to the startup synchronization signal to make the output current of the power converters connected to the same time-sharing multiplexing bus tend to be consistent.

[0044] When the control unit in each power converter detects an initialization synchronization signal at a preset level on the time-division multiplexing bus, each power converter starts the startup process. During this process, the time-division multiplexing bus becomes the current sharing bus, and then the current equalization unit performs the current sharing process.

[0045] In the current sharing process, both passive and active current sharing will be involved, depending on the debugging effect. Generally, they will be used in combination. The specific processes of passive and active current sharing will be described below.

[0046] In one embodiment, such as Figure 1 As shown, the current equalization unit includes an active current sharing unit and a passive current sharing unit; the passive current sharing unit and the active current sharing unit are respectively connected to the control unit, and the active current sharing unit is connected to the time-division multiplexing bus.

[0047] In the current sharing process, taking passive current sharing followed by active current sharing as an example, to facilitate a clear understanding of this invention, the stages experienced by the power converter are first explained: After the power converter is powered on, it first performs an initialization operation. After all power converters connected to the time-sharing bus complete initialization, all power converters start simultaneously under the drive of the startup synchronization signal. After simultaneous startup, each power converter adjusts its own current sequentially through the passive current sharing stage and the active current sharing stage to make the output current of the power converters connected to the same time-sharing bus tend to be consistent.

[0048] Specifically, the step of outputting initialization synchronization signals of different levels according to the initialization status of the power converter includes:

[0049] At the initial initialization stage, the startup synchronization unit outputs an initialization synchronization signal with a first level to the time-division multiplexing bus, indicating that the power converter is initializing but has not yet completed initialization. When the startup synchronization unit detects that the power converter has completed initialization, it outputs an initialization synchronization signal with a second level to the time-division multiplexing bus. In one embodiment, the first level can be high and the second level can be low. In other embodiments, the first level can be low and the second level can be high, as long as it can represent different states, no specific limitation is made here.

[0050] The control unit continuously samples the initialization synchronization signal on the time-division multiplexing bus. When an initialization synchronization signal at a preset level is continuously detected on the time-division multiplexing bus, it indicates that all power converters connected to the time-division multiplexing bus have completed initialization. Here, "continuously" means that each sampled initialization synchronization signal is at the preset level within a certain time period; the preset level refers to the second level mentioned above.

[0051] After all power converters have been initialized, the control unit outputs a startup synchronization signal to the startup synchronization unit and the passive current sharing unit; the startup synchronization unit controls the corresponding power converter to start according to the startup synchronization signal.

[0052] The passive current sharing unit is used to perform passive current sharing on the power converter according to the startup synchronization signal until the power supply voltage output by the power converter reaches a stable state.

[0053] When the power supply voltage output by the power converter reaches a stable state, the active current sharing unit is used to convert the current output by the power converter itself into a voltage feedback signal and transmit the voltage feedback signal to the time-sharing bus; the control unit is used to issue an adjustment command to the active current sharing unit according to the voltage feedback signal, and the active current sharing unit is used to dynamically adjust the output current of the power converter according to the adjustment command so that the output current of the power converters connected to the same time-sharing bus tends to be consistent.

[0054] In this embodiment, the time-division multiplexing bus is used to transmit initialization synchronization signals and voltage feedback signals from different power converters. Each power converter collects the initialization synchronization signal on the time-division multiplexing bus. If an initialization synchronization signal at a preset level appears on the time-division multiplexing bus, it indicates that all power converters connected to the same time-division multiplexing bus have completed initialization and can be started simultaneously. If the voltage feedback signals collected on the time-division multiplexing bus tend to be consistent, the output current of the power converters connected to the same time-division multiplexing bus tends to be consistent.

[0055] In one embodiment, such as Figure 2 As shown, the power supply device for parallel connection of multiple power converters includes at least two of the power converters (n are shown in the figure). Each power converter is shown as Power in the figure, the first power converter is Power_1, and so on, with the nth power converter being Power_n.

[0056] In one embodiment, refer to Figure 2The power converter also includes a sampling bus (i.e., an MCU sampling bus), which is located between the control unit and the time-division multiplexing bus. The control unit is used to collect relevant signals from the time-division multiplexing bus in real time through the sampling bus.

[0057] The MCU sampling bus is located between the control unit and the time-division multiplexing bus. The control unit collects relevant signals (including initialization synchronization signals and voltage feedback signals) from the time-division multiplexing bus in real time through the MCU sampling bus.

[0058] The control unit is used for core regulation, real-time monitoring of various parameters in the power supply device and receiving feedback information from other units, while sending control commands to other units according to the real-time status of the power supply device.

[0059] The startup synchronization unit is used to ensure that different power converters in the power supply device start up synchronously. The startup synchronization unit and the control unit cooperate with each other. The control unit sends a startup synchronization signal to the startup synchronization unit according to the real-time status of the device. The startup synchronization unit performs synchronization control operation according to the startup synchronization signal to control the corresponding power converter to start supplying power to the outside, and feeds back the synchronization processing result to the control unit.

[0060] In one embodiment, the passive current sharing unit is used to achieve low-precision current sharing distribution during the transition phase under the control of the control unit through its own impedance characteristics. When multiple power converters are connected in parallel, uneven current distribution will occur due to factors such as differences in internal resistance between the power converters. The passive current sharing unit uses its fixed impedance to enable the current of each power converter to automatically tend to balance.

[0061] The active current sharing unit further achieves more precise current sharing through active adjustment. It dynamically adjusts the output current of the power converter based on the result of the passive current sharing unit to ensure that the current of each power converter eventually tends to be consistent. The control unit sends adjustment commands to the active current sharing unit based on the detected current of each power converter. The active current sharing unit performs precise adjustment according to the adjustment commands until the output current of each power converter tends to be consistent.

[0062] In one embodiment, the timing control on the time-division multiplexing bus includes three stages: a synchronous startup stage, a passive current sharing stage, and an active current sharing stage. The synchronous startup stage is used to synchronize the simultaneous startup of each power converter. The passive current sharing stage is used to coarsely adjust the output voltage of the power converter. The active current sharing stage is used to finely adjust the output current of the power converter.

[0063] The time-division multiplexing bus serves as a single independent signal line for transmitting initialization synchronization signals and voltage feedback signals among multiple power converters in a time-division manner. This allows all power converters to share the same start-up trigger condition and active current sharing feedback information, ensuring that multiple power converters simultaneously execute the start-up process after the control unit detects the start-up synchronization signal on the MCU sampling bus. This avoids the problem of asynchronous start-up times of various power converters caused by differences in the initialization time of the control unit. Furthermore, the voltage feedback signal detected by the control unit on the MCU sampling bus enables active current sharing among different power converters to improve the accuracy of the output current.

[0064] In one embodiment, such as Figure 3 As shown, the power converter further includes a start-up isolation unit and a current sharing isolation unit. The input terminal of the start-up isolation unit is connected to the start-up synchronization unit, and the output terminal of the start-up isolation unit is connected to the time-division multiplexing bus. The input terminal of the current sharing isolation unit is connected to the active current sharing unit, and the output terminal of the current sharing isolation unit is connected to the time-division multiplexing bus. The control terminals of the start-up isolation unit and the current sharing isolation unit are respectively connected to the control unit. The start-up isolation unit is used to control the transmission of the initialization synchronization signal to the time-division multiplexing bus; the current sharing isolation unit is used to control the transmission of the voltage feedback signal to the time-division multiplexing bus.

[0065] More specifically, during the initialization phase, the synchronous isolation unit is used to allow the initialization synchronization signal to be transmitted to the time-division multiplexing bus, and the current sharing isolation unit is used to prevent the voltage feedback signal from being transmitted to the time-division multiplexing bus, so as to realize the time-division multiplexing function.

[0066] During the passive current sharing phase, the co-start isolation unit is used to prevent the initialization synchronization signal from being transmitted to the time-division multiplexing bus, and the current sharing isolation unit is used to prevent the voltage feedback signal from being transmitted to the time-division multiplexing bus.

[0067] During the active current sharing phase, the synchronous isolation unit is used to prevent the initialization synchronization signal from being transmitted to the time-division multiplexing bus, and the current sharing isolation unit is used to allow the voltage feedback signal to be transmitted to the time-division multiplexing bus, so as to achieve active current sharing.

[0068] The synchronous isolation unit is also used for electrical isolation to prevent current backflow or signal interference (such as grounding interference or load effect) between power converters through the time-division multiplexing bus. The synchronous isolation unit is also used for unidirectional signal transmission to ensure that each power converter only outputs its own status to the time-division multiplexing bus and is not directly affected by the output circuits of other power converters.

[0069] The current sharing isolation unit is used to work in conjunction with the active current sharing unit to send the voltage feedback signal output by the active current sharing unit to the time-division multiplexing bus to achieve accurate current sharing.

[0070] The control unit is connected to the control terminals of the synchronous start-up isolation unit and the current sharing isolation unit, respectively. It controls the connection and disconnection between the start-up synchronization unit and the time-sharing multiplexing bus, and between the active current sharing unit and the time-sharing multiplexing bus, at three different stages of timing control on the time-sharing multiplexing bus, to avoid signal conflicts at different stages. More specific control methods are described in the following embodiments, and will not be elaborated upon here.

[0071] Next, we will introduce passive current sharing: The core principle of passive current sharing is to utilize the characteristic that the output voltage of a power converter slightly decreases as the output current increases to achieve current sharing. That is, when the output current (I_out) of a power converter increases, the output voltage (V_out) of that power converter will decrease slightly according to a preset slope (called the Droop slope or current sharing slope). Its output voltage-current (VI) relationship is not a horizontal line, but a straight line with a negative slope. The slope of this straight line (ΔV / ΔI) is the Droop resistance value (usually in mΩ). It defines how many mV the output voltage will drop for every 1A increase in output current. R_droop = -(dV_out / dI_out).

[0072] The working principle of passive current sharing is as follows:

[0073] Suppose that due to minor differences (such as component tolerances, wiring resistance, etc.), power converter A instantaneously provides a slightly larger current than power converter B. According to the droop characteristic, power converter A, because of its larger output current (I_A), will experience a greater drop in output voltage (V_A): V_A = V_nl - I_A × R_droop. Power converter B, because of its smaller output current (I_B), will experience a smaller drop in output voltage (V_B): V_B = V_nl - I_B × R_droop.

[0074] Since V_B > V_A (the output voltage of power converter B is now higher than that of power converter A), the voltage on the load bus, determined by all parallel power converters, will tend towards an intermediate value. Currently, the output voltage (V_B) of power converter B is more likely to be higher than the bus voltage, meaning power converter B is "capable" of providing more current. The output voltage (V_A) of power converter A is more likely to be lower than the bus voltage, meaning power converter A is "suppressed" from providing current. Therefore, the output current (I_B) of power converter B will naturally increase, while the output current (I_A) of power converter A will naturally decrease. This adjustment process will continue until the output voltages of all parallel power converters are equal (V_A = V_B = ... = V_bus).

[0075] According to the Droop formula V_bus = V_nl - I_x × R_droop, since all power converters have the same V_nl and R_droop are also designed to be the same, the only solution to make V_bus equal is that the output current I_x of all power converters must also be equal.

[0076] That is, I_A=I_B=...=I_total / N, thus making the system eventually stabilize in a flow-equalizing state.

[0077] Next, we will introduce active current sharing: Active current sharing, also known as power converter-based current sharing, is the mainstream method for achieving high-precision load current balancing in power converter-based power systems. Unlike drop-op current sharing (passive current sharing) without interconnection lines, active current sharing actively coordinates the output current of each power converter through a dedicated communication line (time-division multiplexing bus) between power converters, achieving near-precise current sharing. Its core principle is as follows:

[0078] 1. Core idea:

[0079] By real-time detection of the output current of each power converter and the use of a shared time-division multiplexing bus to transmit voltage feedback signals, the output current of all parallel power converters is forced to track the same target value, thereby achieving high-precision current sharing (the error can be controlled within ±2%~±5%).

[0080] 2. Basic Principles and Work Process:

[0081] Each power converter internally measures its own output current Iout in real time through a precision sensing resistor, current transformer, or MOSFET on-resistance, and converts it into a voltage signal Vsense (i.e., voltage feedback signal).

[0082] All parallel power converters are connected by a common low-impedance analog signal line (i.e., time-division multiplexed bus). The current-sharing bus voltage Vshare on this time-division multiplexed bus represents the current reference value required by the system (the specific logic depends on the current-sharing control strategy).

[0083] According to the definition method of the current-sharing bus voltage Vshare, there are mainly two active current-sharing schemes:

[0084] a) Average current method:

[0085] The current-sharing bus voltage Vshare = the average value of the Vsense of all power converters. Each power converter compares its own Vsense with Vshare. If Vsense < Vshare (its own current is too small), increase the output voltage of this power converter to increase its own output current.

[0086] If Vsense > Vshare (its own current is too large), decrease the output voltage of this power converter to reduce its own output current.

[0087] The ultimate goal: make the Vsense of all power converters = Vshare, that is, the currents of all power converters are equal.

[0088] b) Maximum current method:

[0089] The current-sharing bus voltage Vshare = the maximum value of the Vsense of all power converters.

[0090] The power converter with the largest output current becomes the temporary main power converter, and its Vsense determines Vshare.

[0091] Other power converters compare their own Vsense with the Vshare of the main power converter:

[0092] If Vsense < Vshare (its own current < the current of the main power converter), increase the output voltage of this power converter to increase its own current. The ultimate goal is that the currents of all power converters converge to the current of the main power converter until all currents are equal (at this time, the Vsense of all power converters = Vshare).

[0093] Then, the voltage reference is adjusted. A current-sharing error amplifier is introduced into the voltage control loop of each power converter. This current-sharing error amplifier compares Vsense and Vshare and generates an error signal ΔV.

[0094] ΔV is superimposed on the voltage reference Vref of the power converter: when an increase in current is needed, the actual voltage reference is increased, the power converter output voltage rises, and the output current increases. When a decrease in current is needed, the actual voltage reference is decreased, the power converter output voltage decreases, and the output current decreases. The entire process is a fast and continuous negative feedback regulation, thereby achieving active current sharing.

[0095] In one embodiment, the startup synchronization unit, the passive current sharing unit, the active current sharing unit, the co-start isolation unit, and the current sharing isolation unit can be independent modules or functional modules written into the control unit by software. This embodiment uses an independent module as an example for illustration. The structure of writing into the control unit by software will be described in other embodiments.

[0096] In summary, this embodiment dynamically transmits initialization synchronization signals or voltage feedback signals on a single time-division multiplexing bus, replacing the independent synchronization signal line and current sharing bus in traditional solutions. This avoids the linear increase in wiring complexity caused by the increase in the number of power converters, significantly reducing system complexity and hardware costs. Furthermore, reducing the number of signal lines can reduce hardware costs; reducing the number of single signal lines reduces system costs by approximately 5%-15%. At the same time, in high-density installation scenarios, wiring management costs can be reduced by more than 20%, significantly improving system economy.

[0097] Example 2:

[0098] This embodiment will introduce another structure of the power converter, such as in one embodiment. Figure 4 As shown, the power converter includes a control module connected to a time-division multiplexing bus. The control module is used to send initialization synchronization signals and voltage feedback signals to the time-division multiplexing bus, and to collect the signal status on the time-division multiplexing bus.

[0099] The time-division multiplexing bus is used to transmit initialization synchronization signals and voltage feedback signals for different power converters.

[0100] In this embodiment, the initialization synchronization signal and voltage feedback signal proposed in Example 1 are generated in the control module using software methods, and transmitted to the time-division multiplexing bus at different times. That is, the control unit, startup synchronization unit, passive current sharing unit, and active current sharing unit proposed in Example 1 are integrated into a single control module via software. In one embodiment, the control module is an STM32H743VIT6 or a DSPIC33. The specific method and process will not be described in detail here.

[0101] In one embodiment, refer to Figure 4The power converter further includes a switching module. The control module is connected to one end of the switching module, and the other end of the switching module is connected to the time-division multiplexing bus. The switching module is used to selectively transmit the initialization synchronization signal or the voltage feedback signal to the time-division multiplexing bus at different times.

[0102] In one embodiment, the switching module includes a co-start isolation unit and a current sharing isolation unit; both the co-start isolation unit and the current sharing isolation unit are multi-channel selection switches, wherein the multi-channel selection switch includes at least two selection channels. The co-start isolation unit is used to selectively transmit the initialization synchronization signal to the time-division multiplexing bus, and the current sharing isolation unit is used to selectively transmit the voltage feedback signal to the time-division multiplexing bus.

[0103] In one embodiment, both the co-start isolation unit and the current sharing isolation unit are two-to-one switches. In other embodiments, the co-start isolation unit and the current sharing isolation unit can also be three-channel selection switches or four-channel selection switches, etc. In actual use, only two channels of the multi-channel selection switch need to be used for switching.

[0104] In one embodiment, refer to Figure 4 The switching module includes a synchronous isolation unit. The IO1 port of the control module is connected to the control terminal of the synchronous isolation unit. The IO3 port of the control module is connected to the time-division multiplexing bus. The time-division multiplexing bus is connected to the common terminal (i.e., X terminal) on the synchronous isolation unit. The IO2 port of the control module is connected to the first switching terminal (i.e., NC2 terminal) on the synchronous isolation unit. The second switching terminal (i.e., NO2 terminal) on the synchronous isolation unit is left unconnected. The synchronous isolation unit is used to transmit the initialization synchronization signal to the time-division multiplexing bus at different times.

[0105] Specifically, when the common terminal on the co-start isolation unit is connected to its first switching terminal, the co-start isolation unit is used to transmit the initialization synchronization signal to the time-division multiplexing bus; when the common terminal on the co-start isolation unit is connected to its second switching terminal, the co-start isolation unit is used to prevent the transmission of the initialization synchronization signal to the time-division multiplexing bus.

[0106] In one embodiment, refer to Figure 4The switching module further includes a current sharing isolation unit, and the IO4 port of the control module is also connected to the control terminal of the current sharing isolation unit; the ADC port of the control module is connected to the time-division multiplexing bus, the time-division multiplexing bus is connected to the common terminal (i.e., Y terminal) on the current sharing isolation unit, the DAC port of the control module is connected to the first switching terminal (i.e., NO1 terminal) on the current sharing isolation unit, and the second switching terminal (i.e., NC1 terminal) on the current sharing isolation unit is disconnected; the current sharing isolation unit is used to transmit the voltage feedback signal to the time-division multiplexing bus at different times.

[0107] Specifically, when the common terminal of the current sharing isolation unit is connected to its first switching terminal, the current sharing isolation unit is used to transmit the voltage feedback signal to the time-division multiplexing bus; when the common terminal of the current sharing isolation unit is connected to its second switching terminal, the current sharing isolation unit is used to prevent the voltage feedback signal from being transmitted to the time-division multiplexing bus.

[0108] In the simultaneous start isolation unit and the current sharing isolation unit, the switching from the common terminal to the corresponding first switching terminal or second switching terminal is controlled by the control module. Specifically, the control module sends corresponding control signals through the IO1 port to control the connection and disconnection between the common terminal of the simultaneous start isolation unit and the first switching terminal and the second switching terminal; the control module sends corresponding control signals through the IO4 port to control the connection and disconnection between the common terminal of the current sharing isolation unit and the first switching terminal and the second switching terminal. This control method is existing technology, and the specific control method will not be described in detail in this embodiment.

[0109] In one embodiment, the co-start isolation unit and the current sharing isolation unit have the same function as the co-start isolation unit and the current sharing isolation unit proposed in Embodiment 1. The current sharing isolation unit and the co-start isolation unit can be integrated into one module. The model of the switching module is TPW3223.

[0110] In other embodiments, the co-start isolation unit and the current sharing isolation unit are both independent switching units, that is, they can be single devices, to control the transmission of the two signals respectively.

[0111] In one embodiment, the switching module only needs to control the transmission of the initialization synchronization signal and voltage feedback signal to the time-division multiplexing bus at different times. The switching module can also have other structures, and other structures of the switching module will not be described in detail in this embodiment.

[0112] This embodiment dynamically transmits initialization synchronization signals or voltage feedback signals on a single time-division multiplexing bus, replacing the independent synchronization signal line and current sharing bus in the traditional solution. This avoids the linear increase in wiring complexity caused by the increase in the number of power converters, and significantly reduces system complexity and hardware cost. Furthermore, reducing the number of signal lines can reduce hardware cost. Reducing the number of single signal lines reduces system cost by about 5%-15%. At the same time, in high-density installation scenarios, wiring management costs can be reduced by more than 20%, significantly improving system economy.

[0113] Example 3:

[0114] This embodiment proposes a power supply device, including at least two power converters as described in Embodiment 1 or Embodiment 2 and a time-division multiplexing bus. The startup synchronization unit, the current balancing unit, and the control unit are respectively connected to the time-division multiplexing bus. During the initialization of the power converters, the startup synchronization unit outputs initialization synchronization signals of different levels according to the initialization status of the power converters. The control unit continuously samples the initialization synchronization signals on the time-division multiplexing bus. When an initialization synchronization signal of a preset level is detected on the time-division multiplexing bus, the control unit outputs a startup synchronization signal to the startup synchronization unit and the current balancing unit. The startup synchronization unit controls the startup of the corresponding power converter according to the startup synchronization signal. The current balancing unit performs current sharing control on the power converters according to the startup synchronization signal, so that the output current of the power converters connected to the same time-division multiplexing bus tends to be consistent.

[0115] In one embodiment, such as Figure 5 As shown, the power supply device proposed in this embodiment includes two power converters as proposed in Embodiment 1. The current balancing unit includes an active current sharing unit and a passive current sharing unit. The passive current sharing unit and the active current sharing unit are respectively connected to the control unit, and the active current sharing unit is connected to the time-division multiplexing bus. During the initialization of each power converter, the startup synchronization unit is used to output initialization synchronization signals of different levels according to the initialization status of the power converter.

[0116] In one embodiment, the control unit is used to continuously sample the initialization synchronization signal on the time-division multiplexing bus. When an initialization synchronization signal at a preset level is detected on the time-division multiplexing bus, the control unit is used to output a startup synchronization signal to the startup synchronization unit and the passive current sharing unit. The startup synchronization unit is used to control the corresponding power converter to start according to the startup synchronization signal.

[0117] The passive current sharing unit is used to perform passive current sharing on each power converter according to the startup synchronization signal until the power supply voltage output by the power converter reaches a stable state.

[0118] When the power supply voltage output by the power converter reaches a stable state, the active current sharing unit is used to convert the current output by the power converter itself into a voltage feedback signal and transmit the voltage feedback signal to the time-sharing bus; the control unit is used to issue an adjustment command to the active current sharing unit according to the voltage feedback signal, and the active current sharing unit is used to dynamically adjust the output current of the power converter according to the adjustment command so that the output current of the power converters connected to the same time-sharing bus tends to be consistent.

[0119] The control unit continuously samples the voltage feedback signal on the time-division multiplexing bus to determine whether its own current is consistent with the current of other power converters. If its own current is higher than the current of other power converters, it lowers its own current; if its own current is lower than the current of other power converters, it increases its own current to dynamically adjust the current.

[0120] The above description uses a single power converter as a reference to illustrate the function of each module. Other functional modules within the power converter also perform corresponding operations. They mainly use a time-division multiplexing bus to transmit initialization synchronization signals from different power converters, so as to start all power converters synchronously. They also use a time-division multiplexing bus to transmit voltage feedback signals from different power converters, so as to guide each power converter to perform current regulation, so that the output current of power converters connected to the same time-division multiplexing bus tends to be consistent.

[0121] In one embodiment, in a scenario where three or more power converters are connected in parallel, the active current sharing unit achieves high-precision current balancing through signal interaction on the time-division multiplexing bus, multi-signal analysis of the control unit, and closed-loop regulation. The specific mechanism is as follows:

[0122] Each power converter's active current sharing unit includes a current detection module and a voltage conversion module. It can acquire its own output current (such as I1, I2, I3...) through a Hall sensor or a precision sampling resistor, and then linearly convert the current signal into a standardized voltage feedback signal (such as V1, V2, V3..., for example, 1A current corresponds to 1V voltage, ensuring that the voltage and current are strictly proportional).

[0123] During the active current sharing phase, the current sharing isolation unit is enabled by the control unit (receiving the first control signal, such as a low-impedance signal) and transmits each voltage feedback signal (V1, V2, V3, etc.) to the time-division multiplexing bus. Due to the unidirectional transmission characteristic of the current sharing isolation unit (avoiding signal collisions), the voltage on the time-division multiplexing bus ultimately reflects the combined effect of all voltage feedback signals (e.g., equivalent to the "average reference value" of each signal).

[0124] The control unit of each power converter obtains the comprehensive voltage feedback signal on the time-division multiplexed bus in real time through the MCU sampling bus (this signal implicitly contains the current information of all parallel converters). For example, for three converters, the bus voltage V_bus can be equivalent to the average reference value of (V1+V2+V3) / 3 (signal superposition or timing multiplexing is achieved through circuit design to ensure that each signal is effectively acquired).

[0125] The comparison and adjustment logic of the control unit includes: the control unit compares the voltage feedback signal (e.g., V1) of the power converter with the bus voltage V_bus on the time-division multiplexing bus; if V1 > V_bus, it means that its own output current I1 is higher than the average current (I_avg=(I1+I2+I3) / 3); if V1 < V_bus, it means that its own output current I1 is lower than the average current; the deviation threshold is usually set to ±1% (corresponding to the accuracy requirement of active current sharing), and adjustment is triggered when the deviation exceeds the threshold.

[0126] The control unit generates quantifiable adjustment commands (such as "reduce current by 2%" or "increase current by 1.5%) based on the deviation magnitude and sends them to the adjustment execution module of the active current sharing unit (which includes a PWM controller and power transistor drive circuit): If the current needs to be reduced, the adjustment execution module decreases the duty cycle of the power converter switching transistor (e.g., from 50% to 48%) to reduce the output current; if the current needs to be increased, the switching transistor duty cycle is increased (e.g., from 50% to 52%) to increase the output current. The adjustment process uses closed-loop control (such as a proportional-integral algorithm), and the bus signal is resampled after each adjustment until the deviation between its own voltage feedback signal and the bus voltage V_bus is less than ±1%.

[0127] In one embodiment, the dynamic process of multi-power converter coordinated current sharing includes:

[0128] Assume that the initial currents of the three power converters are different: I1=10.5A (V1=10.5V), I2=9.8A (V2=9.8V), I3=9.7A (V3=9.7V), and the bus voltage V_bus=(10.5+9.8+9.7) / 3=10V.

[0129] If V1 (10.5V) > V_bus (10V) is detected, the control unit issues a "reduce by 0.5A" command, which adjusts the execution module to reduce I1 to 10A (V1=10V); if V2 (9.8V) < V_bus (10V) is detected, a "increase by 0.2A" command is issued, which increases I2 to 10A (V2=10V); if V3 (9.7V) < V_bus (10V) is detected, a "increase by 0.3A" command is issued, which increases I3 to 10A (V3=10V); if load fluctuations cause the output current of a power converter to deviate again (e.g., I1 increases to 10.2A), the above sampling-comparison-adjustment process is repeated, ultimately stabilizing the output current of all power converters within the ±1% accuracy range.

[0130] In summary, the active current sharing of three or more power converters achieves signal sharing through a mechanism of "standardized signal transmission - group reference value generation - individual deviation adjustment - dynamic closed-loop correction" and relies on the time-division multiplexing bus to ultimately make the output current of all power converters tend to be consistent, with an accuracy of within ±1%.

[0131] This embodiment dynamically transmits initialization synchronization signals or voltage feedback signals on a single time-division multiplexing bus, replacing the independent synchronization signal line and current sharing bus in the traditional solution. This avoids the linear increase in wiring complexity caused by the increase in the number of power converters, and significantly reduces system complexity and hardware cost. Furthermore, reducing the number of signal lines can reduce hardware cost. Reducing the number of single signal lines reduces system cost by about 5%-15%. At the same time, in high-density installation scenarios, wiring management costs can be reduced by more than 20%, significantly improving system economy.

[0132] Example 4:

[0133] To further illustrate the power supply device described in Embodiment 3, a time-division multiplexing control method will be proposed in this embodiment. In one embodiment... Figure 6 The diagram shows the timing of signal and voltage / current changes on all time-division multiplexing buses in this embodiment. Figure 7 This diagram illustrates the control of the synchronous startup phase (0-t2) in this embodiment. Figure 8 This diagram illustrates the passive flow sharing stage (t2-t3) control in this embodiment. Figure 9 This diagram illustrates the active flow sharing stage (t3-t4) control in this embodiment. Figure 10 This diagram shows a stable current sharing power supply after fine-tuning of the current sharing control in this embodiment (after t4).

[0134] like Figures 6-10As shown, the power supply device includes two power converters, namely Power_1 and Power_2. Here, Share Bus represents a time-division multiplexing bus, SYNC represents the initialization synchronization signal on the time-division multiplexing bus, SYNC1 represents the initialization synchronization signal on Power_1, and SYNC2 represents the initialization synchronization signal on Power_2; VISH1 represents the voltage feedback signal on Power_1, and VISH2 represents the voltage feedback signal on Power_2; Vin+ and Vin- represent the input voltage, Vout+ and Vout- represent the output voltage, Iout represents the output current, I1 represents the first output current of Power_1, and I2 represents the second output current of Power_2. SYNC represents the initialization synchronization signal collected by the control unit from the time-division multiplexing bus, which is different from the issued initialization synchronization signal; VISH is the voltage feedback signal collected by the control unit from the time-division multiplexing bus.

[0135] In one embodiment, Figure 6 The 0-t2 stage shown and Figure 7 This corresponds to the synchronous startup phase; Figure 6 The t2-t3 stage shown and Figure 8 This corresponds to the passive flow equalization phase; Figure 6 The t3-t4 stage shown and Figure 9 This corresponds to the active flow equalization stage; Figure 6 The stage after t4 shown and Figure 10 This represents the stable current sharing power supply stage after fine-tuning of current sharing control.

[0136] In one embodiment, refer to Figure 5 The initialization phase from 0 to t1 is for the first power converter, Power_1, and from 0 to t2 is for the second power converter, Power_2. From t2 to t3 is the passive current sharing phase. During this phase, I1 is the output current of Power_1, and I2 is the output current of Power_2. Vout+ gradually increases from 0 to the target voltage value M, but I1 and I2 still differ by N. That is, after the passive current sharing phase, the output currents of the two power converters are still different, and a current difference of N still exists. From t3 to t4 is the active current sharing phase. Starting at time t3, each power converter begins active current sharing until time t4, when the output currents of both power converters reach A, achieving current sharing. After time t4, the system enters the stable current sharing power supply phase after fine-tuning the current sharing control.

[0137] Based on the power supply device provided in the foregoing embodiments, the time-division multiplexing control method includes: during the initialization of the power converter, the startup synchronization unit outputs initialization synchronization signals of different levels according to the initialization status of the power converter; the control unit continuously samples the initialization synchronization signals on the time-division multiplexing bus, and when an initialization synchronization signal of a continuously preset level appears on the time-division multiplexing bus, the control unit outputs a startup synchronization signal to the startup synchronization unit and the current balancing unit; the startup synchronization unit controls the corresponding power converter to start according to the startup synchronization signal; the current balancing unit performs current sharing control on the power converter according to the startup synchronization signal, so that the output current of the power converters connected to the same time-division multiplexing bus tends to be consistent.

[0138] The current equalization unit includes an active current sharing unit and a passive current sharing unit. In one embodiment, such as... Figure 11 As shown, the time-division multiplexing control method specifically includes:

[0139] Step 101: During the initialization of each power converter, the startup synchronization unit outputs initialization synchronization signals of different levels according to the initialization status of the power converter; the control unit continuously samples the initialization synchronization signal on the time-division multiplexing bus, and when an initialization synchronization signal of a preset level is detected on the time-division multiplexing bus, the control unit outputs a startup synchronization signal to the startup synchronization unit and the passive current sharing unit; the startup synchronization unit controls the corresponding power converter to start according to the startup synchronization signal.

[0140] In one embodiment, refer to Figure 6 During the initialization of each power converter, the startup synchronization unit outputs a high-level initialization synchronization signal to the time-division multiplexing bus. When the startup synchronization unit detects that the power converter has completed initialization, it outputs a low-level initialization synchronization signal to the time-division multiplexing bus. In one embodiment, refer to... Figure 6 The 0-t1 stage is the initialization stage of the first power converter Power_1. Before t1, the initialization synchronization signal SYNC1 sent by the first power converter Power_1 to the time-division multiplexing bus is at a high level (i.e., the first level). At t1, the initialization synchronization signal SYNC1 changes from a high level to a low level (i.e., the second level). After t1, the initialization synchronization signal SYNC1 sent by the first power converter Power_1 to the time-division multiplexing bus is at a low level.

[0141] In one embodiment, the initialization times of different power converters are different. The 0-t2 stage is the initialization stage of the second power converter Power_2. Before t2, the initialization synchronization signal SYNC2 sent by the second power converter Power_2 to the time-division multiplexing bus is at a high level. At t2, the initialization synchronization signal SYNC2 changes from a high level to a low level. After t2, the initialization synchronization signal SYNC2 sent by the second power converter Power_2 to the time-division multiplexing bus is at a low level.

[0142] The t1-t2 stage is the initialization time difference between the first power converter Power_1 and the second power converter Power_2. That is, at t1, the first power converter Power_1 has completed initialization, but the second power converter Power_2 has not yet completed initialization until t2. In other words, at t2, both the first power converter Power_1 and the second power converter Power_2 have completed initialization. At this time, SYNC on the time-division multiplexing bus is at a low level.

[0143] When the MCU sampling buses of both the first power converter Power_1 and the second power converter Power_2 receive a low-level (i.e., preset level) initialization synchronization signal at time t2, the control units in all power converters synchronously use time t2 as the synchronous start-up time node, and simultaneously send start-up synchronization signals to their respective start-up synchronization units and passive current sharing units (e.g., Figure 7 As shown in the figure, after the startup synchronization unit in each power converter obtains the startup synchronization signal, it starts the power converter simultaneously until the voltage stabilizes at t3. The time t3 indicates that each power converter has successfully started up.

[0144] In one embodiment, during the initialization of each power converter, the control unit sends a first control signal to the co-start isolation unit to enable the co-start isolation unit to transmit the first-level initialization synchronization signal issued by the start-up synchronization unit to the time-division multiplexing bus; the control unit sends a second control signal to the current sharing isolation unit to disable the transmission of the voltage feedback signal.

[0145] For further details, please refer to [link / reference]. Figure 7The first power converter Power_1 and the second power converter Power_2 are powered on simultaneously (i.e., they provide input voltages Vin+ and Vin- simultaneously). Each control unit begins to initialize the power converter (including loading programs, configuring registers, detecting sensors, etc.). Each control unit simultaneously sends a first control signal to the co-start isolation unit to enable the co-start isolation unit to send initialization synchronization signals SYNC1 and SYNC2 to the time-division multiplexing bus respectively. Each control unit simultaneously sends a second control signal to the current sharing isolation unit to prevent the current sharing isolation unit from outputting signals (i.e., voltage feedback signals).

[0146] The first control signal can be a low-impedance signal, and the second control signal can be a high-impedance signal. In the following text and accompanying figures, the first control signal is referred to as a low-impedance signal, and the second control signal as a high-impedance signal.

[0147] Step 102: The passive current sharing unit performs passive current sharing on each power converter according to the startup synchronization signal until the power supply voltage output by the power converter reaches a stable state.

[0148] In one embodiment, the condition for determining that the power supply voltage output by the power converter has reached a stable state is: the fluctuation of the power supply voltage output by each power converter is continuously less than 0.5% of the standard value, and the duration exceeds the set time.

[0149] Among them, reference Figure 6 After receiving the startup synchronization signal, the passive current sharing unit begins passive current sharing for each power converter until time t3. At time t3, the passive current sharing unit sends a signal to the control unit to stop passive current sharing (e.g., ...). Figure 8 (As shown).

[0150] In one embodiment, the control unit simultaneously sends a second control signal to the co-start isolation unit and the current sharing isolation unit to disable the signal transmission function of the time-division multiplexing bus; after receiving the start-up synchronization signal, the passive current sharing unit distributes the output current of each power converter through a fixed impedance value so that the power supply voltage output by the power converter reaches a stable state; wherein, the output current accuracy is within the range of -5% to 5%.

[0151] For further details, please see Figure 8When a persistently low initialization synchronization signal is detected on the time-division multiplexing bus, each control unit simultaneously sends a high-impedance signal to the current sharing isolation unit and the co-start isolation unit to prevent the current sharing isolation unit and the co-start isolation unit from transmitting signals to the outside. The control unit and the passive current sharing unit exchange and transmit the start-up synchronization signal. The corresponding passive current sharing unit controls the first power converter Power_1 and the second power converter Power_2 to perform passive current sharing until the first power converter Power_1 and the second power converter Power_2 complete the start-up and the output voltage Vout+ becomes constant. During this period, there are no transmitted signals on the time-division multiplexing bus.

[0152] Step 103: When the power supply voltage output by the power converter reaches a stable state, the active current sharing unit converts the current output by the power converter itself into a voltage feedback signal and transmits the voltage feedback signal to the time-sharing bus; the control unit issues an adjustment command to the active current sharing unit according to the voltage feedback signal, and the active current sharing unit dynamically adjusts the output current of the power converter according to the adjustment command so that the output current of the power converters connected to the same time-sharing bus tends to be consistent.

[0153] When the power supply voltage output by the power converter reaches a stable state, it is necessary to enable the function of the current sharing isolation unit to transmit signals to the time-division multiplexing bus. Then, the control unit sends a first control signal to the current sharing isolation unit to enable the current sharing isolation unit to transmit the voltage feedback signal issued by the active current sharing unit to the time-division multiplexing bus.

[0154] In step 102, the transmission paths of the initialization synchronization signal and the voltage feedback signal have been closed. Therefore, after the passive current sharing stage is completed, that is, when the power supply voltage output by the power converter reaches a stable state, the active current sharing stage needs to be executed. At this time, each power converter needs to transmit voltage feedback signals to the time-division multiplexing bus. Therefore, it is only necessary to send the first control signal to the current sharing isolation unit through the control unit to open the transmission path of the voltage feedback signal, so that the current sharing isolation unit can transmit the voltage feedback signal issued by the active current sharing unit to the time-division multiplexing bus.

[0155] For further details, please see Figure 9Each control unit simultaneously sends a low-impedance signal (i.e., the first control signal) to the current sharing isolation unit to enable the current sharing isolation unit to send voltage feedback signals VISH1 and VISH2 to the time-division multiplexing bus, respectively. During this period, the control unit and the active current sharing unit exchange and transmit voltage feedback signal VISH (VISH is different from voltage feedback signals VISH1 and VISH2, and is obtained from the time-division multiplexing bus). The corresponding active current sharing unit controls the first power converter Power_1 and the second power converter Power_2 to perform active current sharing until the first output current I1 and the second output current I2 are shared to form the output current Iout.

[0156] In one embodiment, voltage feedback signals VISH1 and VISH2 are voltage feedback signals generated by each power converter after converting the output current. By exchanging these two signals on the time-division multiplexing bus (which serves as the current sharing bus in this stage), the control unit uses a closed-loop control algorithm to make VISH1 = VISH2, thereby achieving output current equalization. This process is essentially the conversion of current and voltage signals combined with feedback control. It is the most direct signal interaction method in active current sharing technology and is suitable for systems with dual power converters or multiple power converters connected in parallel. Through real-time comparison and adjustment of voltage signals, it overcomes the accuracy limitations of passive current sharing (such as resistive current sharing), thereby achieving high-precision current sharing.

[0157] In one embodiment, the time-division multiplexing control method further includes: after active current sharing control of each power converter is implemented, the control unit sends a second control signal to the current sharing isolation unit to disable the signal transmission function of the time-division multiplexing bus.

[0158] During the active current sharing phase of each power converter, the transmission path of the initialization synchronization signal has been shut down. Therefore, after the active current sharing phase is completed, it is only necessary to send a second control signal to the current sharing isolation unit to shut down the transmission path of the voltage feedback signal, thereby disabling the signal transmission function of the time-division multiplexing bus.

[0159] For further details, please refer to [link / reference]. Figure 10 Each control unit sends a high-impedance signal to the current sharing isolation unit to prevent the current sharing isolation unit from outputting signals to the outside. During this stage, the first power converter Power_1 and the second power converter Power_2 provide stable voltage and high-precision uniform current to the outside.

[0160] Furthermore, once active current sharing control is implemented for each power converter, each power converter maintains a current sharing power supply state. When current imbalance is detected, active current sharing control is re-triggered.

[0161] It should be noted that, for ease of understanding, this embodiment is illustrated using a power supply device that includes two power converters. In other embodiments, the power supply device may include three, four, or more power converters. The implementation process of the time-division multiplexing control method is similar and will not be repeated here.

[0162] In summary, this embodiment, through a synchronous startup mechanism, ensures that all power converters start and output voltage at the same time node (t2), completely solving the startup asynchrony problem caused by MCU initialization time differences. It reduces the peak surge current from 3 times the rated current to a safe range, effectively protecting power devices (such as significantly reducing the increase in MOSFET on-resistance from over 20%) and extending system life. The reduced number of cables leads to an exponential decrease in the failure rate, avoiding signal interference (such as grounding interference and load effects) and maintenance difficulties caused by complex wiring in traditional solutions. It is especially suitable for scenarios with extremely high reliability requirements, such as aerospace and medical equipment.

[0163] Furthermore, the control unit collects signals on the bus in real time through the MCU sampling bus, and dynamically adjusts the control strategy in combination with feedback information from each unit (such as synchronization processing results and current distribution status) to achieve closed-loop control of the entire process from startup to current sharing, ensuring that the system can quickly recover stability under conditions such as sudden load changes; through the synergistic effect of synchronous startup and high-precision current sharing, the output voltage fluctuation is controlled within 0.1%, meeting the extreme requirements of voltage stability for medical equipment and other devices.

[0164] For the specific structure of the power converter, please refer to Embodiments 1 and 2, which will not be repeated in this embodiment.

[0165] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A power converter, characterized by, In a power supply device for parallel connection of multiple power converters, the power converter includes a control module, which is connected to a time-division multiplexing bus. The control module is used to send initialization synchronization signals and voltage feedback signals to the time-division multiplexing bus, and to collect the signal status on the time-division multiplexing bus; the time-division multiplexing bus is used to transmit initialization synchronization signals and voltage feedback signals of different power converters.

2. The power converter of claim 1, wherein, The power converter further includes a switching module, the control module is connected to one end of the switching module, and the other end of the switching module is connected to the time-division multiplexing bus. The switching module is used to selectively transmit the initialization synchronization signal or the voltage feedback signal to the time-division multiplexing bus at different times.

3. The power converter of claim 2, wherein, The switching module includes a co-start isolation unit and a current sharing isolation unit; both the co-start isolation unit and the current sharing isolation unit are multi-channel selection switches, wherein the multi-channel selection switch includes at least two selection channels.

4. The power converter of claim 3, wherein, The IO1 port of the control module is connected to the control terminal of the co-start isolation unit; the IO3 port of the control module is connected to the time-division multiplexing bus, the time-division multiplexing bus is connected to the common terminal on the co-start isolation unit, the IO2 port of the control module is connected to the first switching terminal on the co-start isolation unit, and the second switching terminal on the co-start isolation unit is left empty. The synchronous isolation unit is used to transmit the initialization synchronization signal to the time-division multiplexing bus at different times.

5. The power converter of claim 3, wherein, The IO4 port of the control module is connected to the control terminal of the current sharing isolation unit; the ADC port of the control module is connected to the time-division multiplexing bus, the time-division multiplexing bus is connected to the common terminal on the current sharing isolation unit, the DAC port of the control module is connected to the first switching terminal on the current sharing isolation unit, and the second switching terminal on the current sharing isolation unit is disconnected; the current sharing isolation unit is used to transmit the voltage feedback signal to the time-division multiplexing bus at different times.

6. The power converter according to claim 3, characterized in that, The simultaneous start isolation unit and the current sharing isolation unit are integrated into one module.

7. The power converter of claim 6, wherein, The switching module is model TPW3223.

8. The power converter of claim 3, wherein, Both the simultaneous start isolation unit and the current sharing isolation unit are independent switching units.

9. The power converter of any of claims 1-8, wherein, The control module is either an STM32H743VIT6 or a DSPIC33.

10. A power supply device, characterized by comprising: It includes at least two power converters as described in any one of claims 1-9 and a time-division multiplexing bus, wherein at least two of the power converters are connected to the time-division multiplexing bus.

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