Voltage converter, power supply and method of controlling the same

Abstract

Embodiments of the present application provide a voltage converter, a power supply and a control method thereof. The voltage converter includes a converter module, which converts an input voltage into an output voltage; a current sharing end, which is connected in parallel with a current sharing end of at least one other voltage converter; and a control circuit, which generates a first voltage signal proportional to an output current of the converter module at an adjustable first proportional coefficient and outputs the first voltage signal to the current sharing end; wherein the first proportional coefficient is selected based on whether the voltage converter is a master voltage converter or a slave voltage converter in a current sharing mode; generates a first current signal proportional to a second voltage signal at the current sharing end at a second proportional coefficient, the second voltage signal being a maximum voltage signal among the first voltage signal and a voltage signal from the other current sharing end; subtracts the output current of the converter module from the first current signal to generate an error current signal; and adjusts the output voltage of the converter module based on the error current signal.

Description

Technical Field

[0001] This application generally relates to the field of power supplies, and more specifically to voltage converters, power supplies, and methods for controlling them. Background Technology

[0002] Active current sharing is widely used in redundant operation of DC / AC and DC / DC converters. Multiple voltage converter outputs are connected together so that the total output power of the converters meets the power requirements of the application under power redundancy conditions.

[0003] The voltage converters involved in the current-sharing method may include a master voltage converter and one or more slave voltage converters. In practical applications, frequent master-slave switching may occur due to various reasons (such as inconsistent performance parameters of the individual voltage converters involved).

[0004] Therefore, a technology is needed to address the frequent occurrence of master-slave swaps. Summary of the Invention

[0005] To address the aforementioned problems, embodiments of this disclosure provide a voltage converter, a power supply, and a control method thereof.

[0006] One aspect of this disclosure provides a voltage converter, including:

[0007] A converter module that converts an input voltage into an output voltage;

[0008] A current-sharing terminal, which is connected in parallel with the current-sharing terminal of at least one other voltage converter; and

[0009] Control circuit, the control circuit:

[0010] A first voltage signal proportional to the output current of the converter module with an adjustable first scaling factor is generated and output to the current sharing terminal; wherein, the first scaling factor is selected based on whether the voltage converter is a master voltage converter or a slave voltage converter in the current sharing mode;

[0011] A first current signal is generated that is proportional to the second voltage signal at the current sharing terminal by a second proportionality factor. The second voltage signal is the maximum voltage signal among the first voltage signal and voltage signals from other current sharing terminals connected in parallel. The first proportionality factor is less than or equal to the reciprocal of the second proportionality factor.

[0012] The output current of the converter module is subtracted from the first current signal to generate an error current signal;

[0013] The output voltage of the converter module is adjusted based on the error current signal.

[0014] According to some embodiments, subtracting the output current of the converter module from the first current signal to generate an error current signal includes:

[0015] The output current and margin current of the converter module are subtracted from the first current signal to generate an error current signal.

[0016] According to some embodiments, the control circuit further includes:

[0017] The comparison circuit compares the first voltage signal with the second voltage signal and outputs the larger of the first voltage signal and the second voltage signal as the new second voltage signal.

[0018] According to some embodiments, the control circuit includes:

[0019] At least one amplifier with different amplification factors; and

[0020] A selector is used to select one of the at least one amplifiers to generate the first voltage signal.

[0021] According to some embodiments, when the voltage converter is a slave voltage converter, the value of the first proportional coefficient is less than the reciprocal of the second proportional coefficient; and / or when the voltage converter is a master voltage converter, the value of the first proportional coefficient is equal to the reciprocal of the second proportional coefficient.

[0022] Specifically, when the voltage converter is a slave voltage converter, the value of the first proportional coefficient is between 0.5 and 0.6 times the reciprocal of the second proportional coefficient.

[0023] According to some embodiments, when the voltage converter is a slave voltage converter, and when the voltage converter frequently undergoes master-slave switching, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient is reduced.

[0024] According to some embodiments, when the voltage converter is a slave voltage converter, and when the conversion speed of the voltage converter is slow during a slave-to-master conversion, the ratio of the value of the first proportional coefficient to the reciprocal of the second proportional coefficient is increased.

[0025] Another aspect of this disclosure provides a power supply including a plurality of voltage converters according to the above aspects.

[0026] Another aspect of this disclosure provides a method for controlling a voltage converter, the voltage converter comprising: a converter module for converting an input voltage to an output voltage, a current-sharing terminal for being connected in parallel with a current-sharing terminal of at least one other voltage converter, and a control circuit, the method comprising the control circuit comprising:

[0027] A first voltage signal proportional to the output current of the converter module with an adjustable first scaling factor is generated and output to the current sharing terminal; wherein, the first scaling factor is selected based on whether the voltage converter is a master voltage converter or a slave voltage converter in current sharing mode;

[0028] A first current signal is generated that is proportional to the second voltage signal at the current sharing terminal by a second proportionality factor. The second voltage signal is the maximum voltage signal among the first voltage signal and voltage signals from other current sharing terminals connected in parallel. The first proportionality factor is less than or equal to the reciprocal of the second proportionality factor.

[0029] The output current of the converter module is subtracted from the first current signal to generate an error current signal;

[0030] The output voltage of the converter module is adjusted based on the error current signal.

[0031] According to some embodiments, subtracting the output current of the converter module from the first current signal to generate an error current signal includes:

[0032] The output current and margin current of the converter module are subtracted from the first current signal to generate an error current signal.

[0033] According to some embodiments, the method further includes:

[0034] The first voltage signal is compared with the second voltage signal, and the larger of the first voltage signal and the second voltage signal is output as the new second voltage signal.

[0035] According to some embodiments, generating a first voltage signal that is proportional to the output current of the converter module with an adjustable first scaling factor includes selecting one of at least one amplifier with different amplification factors to generate the first voltage signal.

[0036] According to some embodiments, when the voltage converter is a slave voltage converter, the value of the first proportional coefficient is less than the reciprocal of the second proportional coefficient; and / or when the voltage converter is a master voltage converter, the value of the first proportional coefficient is equal to the reciprocal of the second proportional coefficient.

[0037] Specifically, when the voltage converter is a slave voltage converter, the value of the first proportional coefficient is between 0.5 and 0.6 times the reciprocal of the second proportional coefficient.

[0038] According to some embodiments, when the voltage converter is a slave voltage converter, and when the voltage converter frequently undergoes master-slave switching, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient is reduced.

[0039] According to some embodiments, when the voltage converter is a slave voltage converter, and when the conversion speed of the voltage converter is slow during a slave-to-master conversion, the ratio of the value of the first proportional coefficient to the reciprocal of the second proportional coefficient is increased.

[0040] Another aspect of this disclosure provides a method for designing a power supply, comprising: connecting the current-sharing terminals of a plurality of voltage converters designed according to the method described above in parallel with each other.

[0041] By selecting an adjustable first scaling factor based on whether the voltage converter is a master or slave voltage converter in current-sharing mode, the magnitude of the generated first voltage signal can be selected according to the role of the voltage converter in master-slave current-sharing mode. This makes it more difficult for the magnitude of the first voltage signal of the slave voltage converter to exceed the magnitude of the first voltage signal of the master voltage converter, thereby reducing the frequency of master-slave switching.

[0042] Other advantages may be apparent to those skilled in the art. Some embodiments may lack the advantages described, or may have some or all of the advantages described. Attached Figure Description

[0043] To gain a more complete understanding of the disclosed embodiments, their features and advantages, the following description is now taken in conjunction with the accompanying drawings, in which:

[0044] Figure 1 A schematic diagram of a voltage feedback converter is shown;

[0045] Figure 2 A schematic diagram of another voltage feedback converter is shown;

[0046] Figure 3 A schematic structural diagram of a voltage converter according to an embodiment of this application is shown;

[0047] Figure 4 A schematic arrangement of the power supply according to an embodiment is shown;

[0048] Figure 5 It shows the relationship with Figure 3 The voltage converter shown corresponds to the method for controlling the voltage converter;

[0049] Figure 6 It shows the relationship with Figure 4 The power supply design method corresponding to the power supply; and

[0050] Figure 7 A schematic circuit diagram of a voltage converter according to an embodiment of this application is shown. Detailed Implementation

[0051] Embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0052] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “a,” “an,” and “the,” as used herein, should also include the meanings of “a plurality” and “multiple,” unless the context clearly indicates otherwise. Furthermore, the terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0053] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0054] The accompanying drawings show some block diagrams and / or flowcharts. It should be understood that some blocks or combinations thereof in the block diagrams and / or flowcharts can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when executed by the processor, these instructions can create means for implementing the functions / operations described in these block diagrams and / or flowcharts.

[0055] Therefore, the technology disclosed herein can be implemented in hardware and / or software (including firmware, microcode, etc.). Additionally, the technology disclosed herein can take the form of a computer program product stored on a computer-readable medium, which can be used by or in conjunction with an instruction execution system. In the context of this disclosure, a computer-readable medium can be any medium capable of containing, storing, transmitting, propagating, or transmitting instructions. For example, a computer-readable medium can include, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, apparatuses, or propagation media. Specific examples of computer-readable media include: magnetic storage devices, such as magnetic tape or hard disk drives (HDDs); optical storage devices, such as optical discs (CD-ROMs); memory, such as random access memory (RAM) or flash memory; and / or wired / wireless communication links.

[0056] Figure 1 A schematic diagram of a voltage feedback converter is shown. (For example...) Figure 1 As shown, this voltage feedback converter has a voltage controller loop. The converter's output Vout is amplified by an amplifier with a coefficient of H, and then subtracted from the reference signal Vref to generate an error signal Verr. The error signal Verr is input to a proportional-integral-derivative (PID) controller or a pole / zero controller to generate a control signal for adjusting the converter's output. To prevent current from other converters from flowing back into the converter operating in redundant mode, the converter's output passes through a unidirectional conductive device (diode / rectifier / MOSFET) before flowing into the amplifier with a coefficient of H.

[0057] Figure 2 A schematic diagram of another voltage feedback converter is shown. Figure 2 The commonly used active current method shown uses the output current to generate a current-sharing signal Vlshare. All Vlshare signals of converters connected in parallel are connected together. The Vlshare signal of each converter is proportional to its output current Iout (with a coefficient of K), but due to the unidirectional conductive device D1 (e.g., ...), ... Figure 2 (The diode shown in the diagram) Only the largest Vlshare signal can be fed to the other converters. For the converter with the largest Vout, its output current is the maximum output current, and the Vlshare signal of this converter is fed to all converters, including itself. This converter is called the master voltage converter, and the other converters are called slave voltage converters. Then, the largest Vlshare signal is divided by K and subtracted from the sum of Iout and the margin current signal (Iout + I_MARGIN) to generate the current error signal Ierr, where I_MARGIN is a predefined output current difference, indicating that currents within I_MARGIN are not considered to have substantial differences in the technical solution of this application.

[0058] The current-shared PID controller receives the error signal Ierr and generates an incremental signal DeltaV based on it. DeltaV is added to a fixed nominal reference signal Vref_NOM to generate an adjusted Vref signal, which is used to generate the error signal Verr. The control signal Vc is generated by the Vout PID controller to regulate the converter.

[0059] In some embodiments, DeltaV is limited to being greater than 0 and less than DeltaV_MAX, which is used to limit the maximum Vout adjustment value.

[0060] when Figure 2 When the converter shown is a master voltage converter, Vlshare = K x Iout_master, and Ierr_master equals -I_MARGIN. However, when the input of the current-shared PID controller is negative, the controller output DeltaV_master equals 0, and the master voltage converter output remains unchanged (Vref_master = Vref_NOM).

[0061] when Figure 2 The converter shown is a slave voltage converter, where its output current is less than the master voltage converter's current. When the slave voltage converter's output current is below (Iout_master - I_MARGIN), Ierr_slave = Iout_master - (Iout_slave + I_MARGIN) will be greater than 0. The current-shared PID controller of the slave voltage converter will output a positive DeltaV_slave, which will increase the slave voltage converter's output voltage. If the current-shared PID controller has a high integral gain, Ierr_slave will be close to 0 in steady state, and Iout_slave = Iout_master - I_MARGIN.

[0062] If Iout_master - Iout_slave < I_MARGIN, Ierr_slave will be equal to 0, and DeltaV_slave will also be equal to 0.

[0063] Under steady-state conditions, the output current of the voltage converter will change in accordance with the output current of the main voltage converter.

[0064] Iout_master-Iout_slave<I_MARGIN, or Iout_slave=Iout_master-I_MARGIN,

[0065] Vref_master = Vref_NOM,

[0066] Vref_slave=Vref_NOM+DeltaV_slave (where, 0<=DeltaV_slave<=DeltaV_MAX)

[0067] In implementing the above technical solution, the inventors of this invention discovered that the current-sharing scheme works well under steady-state conditions. However, for dynamic system loads, the operating condition depends on the response of the Vout PID controller, the response of the current-sharing PID controller, and the dynamic response of the converter. In some applications, the converters used in the above current-sharing scheme may not have consistent performance, for example, due to being from different manufacturers or for other reasons. For instance, they may have different converter dynamic responses and / or different Vout PID controller responses and / or different current-sharing PID controller responses. This can easily lead to oscillations in the converter's output voltage and current. When the converter's output current oscillates, Iout_slave may temporarily be higher than Iout_master, causing a master / slave role reversal. In this situation, the oscillation may be difficult to quell because the converters are temporarily in the role of slave voltage converters and are trying to adjust their own outputs. In some solutions, this situation can be improved by increasing the value of I_MARGIN. The larger the value of I_MARGIN, the greater the difference between Iout_slave and Iout_master, which is necessary to cause a master-slave reversal. However, the inventors of this invention have found that this solution may lead to difficulties in meeting the accuracy requirements of current sharing.

[0068] To address this problem, this application proposes a voltage converter, a power supply, and a design method thereof.

[0069] Figure 3 A schematic structural diagram of a voltage converter according to an embodiment of this application is shown. According to the schematic structural diagram, the voltage converter 300 includes a converter module 310, a current sharing terminal 320, and a controller circuit 330.

[0070] The converter module 310 converts the input voltage into the output voltage.

[0071] The current sharing terminal 320 is connected in parallel with the current sharing terminal of at least one other voltage converter.

[0072] Control circuit 330 generates a first voltage signal proportional to the output current of converter module 310 with an adjustable first proportional coefficient and outputs it to current sharing terminal 320; wherein, the first proportional coefficient is selected based on whether voltage converter 300 is a master voltage converter or a slave voltage converter in current sharing mode; generates a first current signal proportional to the second voltage signal at current sharing terminal 320 with a second proportional coefficient, the second voltage signal being the maximum voltage signal among the first voltage signal and voltage signals from other current sharing terminals connected in parallel, the first proportional coefficient being less than or equal to the reciprocal of the second proportional coefficient; subtracts the output current of converter module 310 from the first current signal to generate an error current signal; and adjusts the output voltage of converter module 310 based on the error current signal.

[0073] By selecting an adjustable first scaling factor based on whether the voltage converter 300 is a master voltage converter or a slave voltage converter in the current sharing mode, the magnitude of the generated first voltage signal can be selected according to the role of the voltage converter 300 in the master-slave current sharing mode. This makes it more difficult for the magnitude of the first voltage signal of the slave voltage converter to exceed the magnitude of the first voltage signal of the master voltage converter, thereby reducing the frequency of master-slave switching.

[0074] In some embodiments, subtracting the output current of the converter module 310 from the first current signal to generate an error current signal may include subtracting the output current and the margin current of the converter module 310 from the first current signal to generate an error current signal.

[0075] In some embodiments, the control circuit 330 may further include a comparison circuit 331. The comparison circuit 331 compares the first voltage signal with the second voltage signal and outputs the larger of the first voltage signal and the second voltage signal as the new second voltage signal.

[0076] In some embodiments, the control circuit 330 may include at least one amplifier 332 having different amplification factors; and a selector 333 for selecting one of the at least one amplifiers to generate a first voltage signal. For example, one of the amplifiers 332 corresponds to a master voltage converter role, while the at least one amplifier 332 corresponds to a slave voltage converter role. The selector 333 selects the amplifier or amplification factor to use based on whether the voltage converter 300 is a master voltage converter or a slave voltage converter.

[0077] In some embodiments, when the voltage converter 300 is a slave voltage converter, the value of the first proportional coefficient may be less than the reciprocal of the second proportional coefficient; and / or when the voltage converter 300 is a master voltage converter, the value of the first proportional coefficient may be equal to the reciprocal of the second proportional coefficient.

[0078] Specifically, when the voltage converter 300 is a slave voltage converter, the value of the first proportional coefficient can be between 0.5 and 0.6 times the reciprocal of the second proportional coefficient. However, those skilled in the art will understand that the range of values ​​may vary depending on the specific implementation. Such variations should fall within the scope of the technical solution of this application.

[0079] In some embodiments, when the voltage converter 300 is a slave voltage converter, and when the voltage converter 300 frequently undergoes master-slave switching, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient can be reduced.

[0080] In some embodiments, when the voltage converter 300 is a slave voltage converter, and when the conversion speed of the voltage converter 300 is slow during slave-to-master conversion, the ratio of the value of the first proportional coefficient to the inverse of the second proportional coefficient can be increased.

[0081] Figure 4 A schematic arrangement of the power supply according to an embodiment is shown. (As...) Figure 4 As shown, a current-sharing power supply 400 is formed by connecting the current-sharing terminals of multiple voltage converters 300 in parallel with each other.

[0082] Figure 5 It shows the relationship with Figure 3 The voltage converter 300 shown corresponds to a method 500 for controlling the voltage converter. For example... Figure 3 As shown, the voltage converter 300 includes: a converter module 310 for converting an input voltage to an output voltage, a current-sharing terminal 320 for connecting in parallel with the current-sharing terminals of at least one other voltage converter, and a control circuit 330. The method 500 is executed by the control circuit 330 and includes:

[0083] S510, a first voltage signal proportional to the output current of converter module 310 with an adjustable first scaling factor is generated and output to current sharing terminal 320, wherein the first scaling factor is selected based on whether voltage converter 300 is a master voltage converter or a slave voltage converter in current sharing mode.

[0084] S520, generates a first current signal that is proportional to the second voltage signal at the current sharing terminal 320 by a second proportional coefficient. The second voltage signal is the maximum voltage signal among the first voltage signal and the voltage signals from other current sharing terminals connected in parallel. The first proportional coefficient is less than or equal to the reciprocal of the second proportional coefficient.

[0085] S530, subtract the output current of converter module 310 from the first current signal to generate an error current signal; and

[0086] S540 adjusts the output voltage of converter module 310 based on error current signal.

[0087] By selecting an adjustable first scaling factor based on whether the voltage converter 300 is a master voltage converter or a slave voltage converter in the current sharing mode, the magnitude of the generated first voltage signal can be selected according to the role of the voltage converter 300 in the master-slave current sharing mode. This makes it more difficult for the magnitude of the first voltage signal of the slave voltage converter to exceed the magnitude of the first voltage signal of the master voltage converter, thereby reducing the frequency of master-slave switching.

[0088] In some embodiments, subtracting the output current of the converter module 310 from the first current signal to generate an error current signal may include subtracting the output current and the margin current of the converter module 310 from the first current signal to generate an error current signal.

[0089] In some embodiments, method 500 may further include: comparing a first voltage signal with a second voltage signal, and outputting the larger of the first voltage signal and the second voltage signal as a new second voltage signal. This step may be performed by comparison circuit 331.

[0090] In some embodiments, control circuitry 330 may include at least one amplifier 332 with different amplification factors. Method 500 may include selecting one of the at least one amplifier with different amplification factors to generate a first voltage signal. This step may be performed, for example, by selector 333. For example, one of the amplifiers 332 corresponds to a master voltage converter role, while at least one of the amplifiers 332 corresponds to a slave voltage converter role. Selector 333 selects the amplifier or amplification factor to use based on whether the voltage converter 300 is a master voltage converter or a slave voltage converter.

[0091] In some embodiments, when the voltage converter 300 is a slave voltage converter, the value of the first proportional coefficient may be less than the reciprocal of the second proportional coefficient; and / or when the voltage converter 300 is a master voltage converter, the value of the first proportional coefficient may be equal to the reciprocal of the second proportional coefficient.

[0092] Specifically, when the voltage converter 300 is a slave voltage converter, the value of the first proportional coefficient can be between 0.5 and 0.6 times the reciprocal of the second proportional coefficient. However, those skilled in the art will understand that the range of values ​​may vary depending on the specific implementation. Such variations should fall within the scope of the technical solution of this application.

[0093] In some embodiments, when the voltage converter 300 is a slave voltage converter, and when the voltage converter 300 frequently undergoes master-slave switching, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient can be reduced.

[0094] In some embodiments, when the voltage converter 300 is a slave voltage converter, and when the conversion speed of the voltage converter 300 is slow during slave-to-master conversion, the ratio of the value of the first proportional coefficient to the inverse of the second proportional coefficient can be increased.

[0095] Figure 6 It shows the relationship with Figure 4 The power supply design method corresponding to the power supply is 600. For example... Figure 6 As shown, the method 600 may include step S610, which involves dividing multiple data according to... Figure 5 The current-sharing terminals 320 of the voltage converters 300 controlled by the method shown are connected in parallel with each other.

[0096] To further describe the details of the technical solutions in the embodiments of this application, the following will be based on... Figure 7 The circuit diagram shown illustrates the technical solution of the embodiments of this application.

[0097] To avoid the shock caused by the switching of master / slave roles, the technical solution of this application embodiment will suppress the output of Iout_slave to Vlshare.

[0098] In the role of a voltage converter, DeltaV is set to be greater than 0, and this is used as another value of the control signal K to calculate the first voltage signal. Thus, in Figure 7 In the scheme shown, a low (or even 0) gain K' is chosen so that K'xIout_slave will not be higher than K x Iout_master, and Vlshare is always equal to K x Iout_master.

[0099] In the role of the main voltage converter, DeltaV is set to 0 and used as the control signal to select K for calculating the first voltage signal. In this case, Figure 7 The situation and Figure 2 The situation is the same.

[0100] When K' is chosen to an appropriate value (e.g., much smaller than K), K'xIout_slave of the voltage converter will not be higher than KxIout_master, so the master / slave role will not change easily even under dynamic load conditions.

[0101] When a voltage converter operates as a slave voltage converter but its output current is higher than that of other voltage converters, the input of the current-sharing PID controller for that voltage converter will eventually drop to 0, and the first proportional coefficient used to calculate the first voltage signal will use the gain K. The voltage converter will then switch back to the master voltage converter role and will not be locked into the slave voltage converter role.

[0102] The value of K' depends on the specific implementation. When K' is too small (e.g., much smaller than K), the master / slave role of the voltage converter is indeed not easily changed. However, in this case, when the voltage converter exits the master voltage converter role, another voltage converter (operating as a slave voltage converter) may take a long time to become the master voltage converter. On the other hand, if K' is too large (e.g., close to K), the effect of avoiding frequent master-slave switching will be less significant.

[0103] Therefore, according to some embodiments, the value of K' can be adjusted based on the current operating status of the power supply. For example, when the voltage converter frequently undergoes master-slave switching, it indicates that the current value of K' may be too large, and the frequency of master-slave switching can be reduced by decreasing the value of K'. Conversely, when a slave-to-master switching occurs, if the voltage converter's switching speed is slow, for example, if no voltage converter is able to become the master voltage converter for a long time, the switching speed can be increased by increasing the value of K'.

[0104] The K' value of each voltage converter sharing current in the power supply can be adjusted in any suitable way. For example, it can be centrally controlled by a centralized (micro)controller based on the power supply's operating conditions. For instance, a larger K' value can be assigned (or preferentially adjusted) to voltage converters with better performance and / or greater stability, increasing their likelihood of becoming the primary voltage converter. Of course, any other specific implementation based on the above allocation / adjustment approach can also be adopted. These solutions also fall within the scope of this application.

[0105] For example, in Figure 7 In the circuit diagram shown, a selection switch is used to select the corresponding amplifier / first scaling factor / amplifier gain. This selection switch can be implemented using one or more of the following methods:

[0106] 1. Using an analog signal multiplexer, both K x Iout and K' x Iout are input to the multiplexer, and the multiplexer selects one of the two outputs based on the value of DeltaV.

[0107] 2. Controllable gain amplifier, which selects its gain (the value of K) based on the value of DeltaV.

[0108] 3. A controller implemented by a microcontroller. The microcontroller's analog-to-digital converter samples the Iout, Vlshare, and Vout signals. The Vout PID controller and the current-sharing PID controller can be implemented through firmware, and the value of K can be changed according to DeltaV through firmware.

[0109] The above only lists some implementations of the selector switch, but this application is not limited to these, and any method available in the art can be used to implement the selector switch.

[0110] Although the invention has been shown and described with reference to specific exemplary embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made to this disclosure without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. Therefore, the scope of the invention should not be limited to the above embodiments, but should be determined not only by the appended claims, but also by their equivalents.

Claims

1. A voltage converter, said voltage converter being one of a group of voltage converters for current sharing, said voltage converter comprising: A converter module that converts an input voltage into an output voltage; A current-sharing terminal is connected in parallel with the current-sharing terminals of the other voltage converters in the group of voltage converters; as well as Control circuit, the control circuit: A first voltage signal proportional to the output current of the converter module with an adjustable first scaling factor is generated and output to the current sharing terminal. A first current signal is generated that is proportional to the second voltage signal at the current sharing terminal by a second proportionality factor. The second voltage signal is the maximum voltage signal among the first voltage signal and voltage signals from other current sharing terminals connected in parallel. The first proportionality factor is less than or equal to the reciprocal of the second proportionality factor. The output current of the converter module is subtracted from the first current signal to generate an error current signal; The output voltage of the converter module is adjusted based on the error current signal. Wherein, when the voltage converter is in current-sharing mode as a slave voltage converter, the first proportional coefficient is less than the reciprocal of the second proportional coefficient; and / or Wherein, when the voltage converter is the main voltage converter in the current sharing mode, the value of the first proportional coefficient is equal to the reciprocal of the second proportional coefficient.

2. The voltage converter according to claim 1, wherein, Subtracting the output current of the converter module from the first current signal to generate an error current signal includes: The output current and margin current of the converter module are subtracted from the first current signal to generate an error current signal.

3. The voltage converter according to claim 1, wherein, The control circuit also includes: The comparison circuit compares the first voltage signal with the second voltage signal and outputs the larger of the first voltage signal and the second voltage signal as the new second voltage signal.

4. The voltage converter according to claim 1, wherein, The control circuit includes: At least one amplifier with different amplification factors; and A selector is used to select one of the at least one amplifiers to generate the first voltage signal.

5. The voltage converter according to claim 1, wherein, When the voltage converter is a slave voltage converter, the value of the first proportional coefficient is between 0.5 and 0.6 times the reciprocal of the second proportional coefficient.

6. The voltage converter according to any one of claims 1 to 4, wherein, When the voltage converter is a slave voltage converter, and when the voltage converter frequently undergoes master-slave switching, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient is reduced.

7. The voltage converter according to any one of claims 1 to 4, wherein, When the voltage converter is a slave voltage converter, and when the conversion speed of the voltage converter is slow during slave-to-master conversion, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient is increased.

8. A power supply comprising a plurality of voltage converters according to any one of claims 1 to 7.

9. A method for controlling a voltage converter, said voltage converter being one of a group of voltage converters for current sharing, said voltage converter comprising: A converter module for converting an input voltage to an output voltage, a current-sharing terminal for connecting in parallel with the current-sharing terminals of other voltage converters in the group of voltage converters, and a control circuit, the method comprising the control circuit: A first voltage signal proportional to the output current of the converter module with an adjustable first scaling factor is generated and output to the current sharing terminal. A first current signal is generated that is proportional to the second voltage signal at the current sharing terminal by a second proportionality factor. The second voltage signal is the maximum voltage signal among the first voltage signal and voltage signals from other current sharing terminals connected in parallel. The first proportionality factor is less than or equal to the reciprocal of the second proportionality factor. The output current of the converter module is subtracted from the first current signal to generate an error current signal; The output voltage of the converter module is adjusted based on the error current signal. Wherein, when the voltage converter is in current-sharing mode as a slave voltage converter, the first proportional coefficient is less than the reciprocal of the second proportional coefficient; and / or Wherein, when the voltage converter is the main voltage converter in the current sharing mode, the value of the first proportional coefficient is equal to the reciprocal of the second proportional coefficient.

10. The method according to claim 9, wherein, Subtracting the output current of the converter module from the first current signal to generate an error current signal includes: The output current and margin current of the converter module are subtracted from the first current signal to generate an error current signal.

11. The method of claim 9, further comprising: The first voltage signal is compared with the second voltage signal, and the larger of the first voltage signal and the second voltage signal is output as the new second voltage signal.

12. The method according to claim 9, wherein, Generating a first voltage signal proportional to the output current of the converter module with an adjustable first scaling factor includes: Select one of at least one amplifier with different amplification factors to generate the first voltage signal.

13. The method according to claim 9, wherein, When the voltage converter is a slave voltage converter, the value of the first proportional coefficient is between 0.5 and 0.6 times the reciprocal of the second proportional coefficient.

14. The method according to any one of claims 9 to 12, wherein, When the voltage converter is a slave voltage converter, and when the voltage converter frequently undergoes master-slave switching, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient is reduced.

15. The method according to any one of claims 9 to 12, wherein, When the voltage converter is a slave voltage converter, and when the conversion speed of the voltage converter is slow during slave-to-master conversion, the ratio of the value of the first proportional coefficient to the reciprocal value of the second proportional coefficient is increased.

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