CN117713542A - Circuit for power-down holding of power converter and power supply device - Google Patents

Abstract

The application relates to the technical field of power, discloses a circuit and a power supply device for power-down maintenance of a power converter, and comprises: the power supply converter, the charging energy storage circuit and the ideal diode are connected in parallel and then connected in series with the power supply converter; the charging energy storage circuit comprises an energy storage capacitor, a boost converter and a change-over switch, wherein the boost converter and the change-over switch are connected in series, one end of the energy storage capacitor is grounded, the other end of the energy storage capacitor is connected with the output end of the boost converter, and the change-over switch is conducted when the input voltage of the ideal diode is lower than the undervoltage limit value. Therefore, the boost converter charges the energy storage capacitor after the input voltage is increased, capacitor energy storage occupying the same space is improved, and after power is off, the ideal diode controls the energy storage capacitor to discharge for a longer time, so that the power-down holding time is greatly improved.

Description

Circuit for power-down holding of power converter and power supply device

Technical Field

The present disclosure relates to the field of power technology, and for example, to a circuit and a power supply device for power-down holding of a power converter.

Background

The power down hold time is an important technical parameter of the power supply, and refers to the time difference from when the power supply is powered down to when the output voltage drops below the allowable range (e.g., -5%). With the widespread use of direct current-to-direct current (DC-DC) power converters in electronic devices (including communication devices, servers, etc.), power loss maintenance of DC-DC power converters is also of great concern.

At present, the power-down maintenance of a DC-DC power converter is mainly achieved by means of instantaneous energy storage action of energy storage capacitors which are present in a large number in the circuit. In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art: in order to prolong the power-down holding time of the power converter, the related art designs a larger number of energy storage capacitors with larger capacity at the input end or the output end, which directly leads to the increase of the volume of the power converter, and the power-down holding of the DC-DC power converter needs to occupy larger space.

It should be noted that the information disclosed in the foregoing background section is only for enhancing understanding of the background of the present application and thus may include information that does not form the prior art that is already known to those of ordinary skill in the art.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview, and is intended to neither identify key/critical elements nor delineate the scope of such embodiments, but is intended as a prelude to the more detailed description that follows.

The embodiment of the disclosure provides a circuit and a power supply device for power-down holding of a power converter, so as to improve the efficiency of an energy storage capacitor for power-down holding of the power converter in a unit space and reduce the volume of the energy storage capacitor for power-down holding of the power converter.

In some embodiments, the circuit for power converter power down retention includes: the power supply converter, the charging energy storage circuit and the ideal diode are connected in parallel and then connected in series with the power supply converter;

the charging energy storage circuit comprises an energy storage capacitor, a boost converter and a change-over switch, wherein the boost converter and the change-over switch are connected in series, one end of the energy storage capacitor is grounded, the other end of the energy storage capacitor is connected with the output end of the boost converter, and the change-over switch is conducted when the input voltage of the ideal diode is lower than the undervoltage limit value.

Optionally, the output end of the ideal diode is connected with the input end of the power converter.

Optionally, an input end of the ideal diode is connected with an input power supply, and the input power supply is a direct current power supply.

Optionally, the power converter is a dc-dc power converter.

Optionally, the circuit further includes a first filter capacitor, one end of the first filter capacitor is grounded, and the other end of the first filter capacitor is connected between the input end of the power converter and the output end of the ideal diode.

Optionally, the circuit further includes a second filter capacitor, one end of the second filter capacitor is grounded, and the other end of the second filter capacitor is connected to the output end of the power converter.

Optionally, the power converter is a wide-voltage input power converter.

In some embodiments, a power supply apparatus includes the circuit for power down retention of a power converter as described in the previous embodiments.

The circuit for power-down holding of the power converter and the power supply device provided by the embodiment of the disclosure can realize the following technical effects:

the boost converter disclosed by the invention charges the energy storage capacitor after the input voltage is increased, the energy storage of the capacitor occupying the same space is improved, after the power is off, the time for controlling the energy storage capacitor to discharge by the switch is longer, and the power-off holding time is greatly improved. The power-down holding time of the power converter can be prolonged without increasing the occupied space. In other words, employing embodiments of the present disclosure may reduce the footprint when the same power down retention time is achieved. Particularly, the wide-voltage input DC-DC converter can tolerate higher input voltage and a wider allowable voltage range, so that the energy storage potential of the energy storage capacitor can be furthest exerted, and the power-down holding time is greatly prolonged.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which like reference numerals refer to similar elements, and in which:

fig. 1 is a circuit diagram for power down retention of a power converter provided by an embodiment of the present disclosure.

Detailed Description

So that the manner in which the features and techniques of the disclosed embodiments can be understood in more detail, a more particular description of the embodiments of the disclosure, briefly summarized below, may be had by reference to the appended drawings, which are not intended to be limiting of the embodiments of the disclosure. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may still be practiced without these details. In other instances, well-known structures and devices may be shown simplified in order to simplify the drawing.

The terms first, second and the like in the description and in the claims of the embodiments of the disclosure and in the above-described figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate in order to describe embodiments of the present disclosure. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion.

The term "plurality" means two or more, unless otherwise indicated.

In the embodiment of the present disclosure, the character "/" indicates that the front and rear objects are an or relationship. For example, A/B represents: a or B.

The term "and/or" is an associative relationship that describes an object, meaning that there may be three relationships. For example, a and/or B, represent: a or B, or, A and B.

The term "corresponding" may refer to an association or binding relationship, and the correspondence between a and B refers to an association or binding relationship between a and B.

In communication and service applications, after the system detects that the input power supply is powered down, the system needs to store and transmit data, set the state of the actuator and the like, so that after the input power is powered down, the power supply also needs to continuously provide power for the system for a period of time so as to ensure that the system is reliably turned off; meanwhile, in an uninterruptible power supply (Uninterruptible Power Supply, UPS) system, a switching gap from mains supply to UPS supply also needs to maintain normal output, which also needs to meet a certain power failure maintaining time requirement, generally in the order of tens of milliseconds.

Therefore, the power down hold time is an important technical parameter of the power supply, which refers to the time difference from when the power supply is powered down to when the output voltage drops below the allowable range (e.g., -5%).

Currently, with the widespread use of power converters in electronic devices (including communication devices, servers, etc.), power loss maintenance of power converters is also a great concern. However, the power down retention of the power converter is achieved primarily by the instantaneous energy storage action of the energy storage capacitor, which is present in large numbers in the circuit.

In the power conversion circuit, a large-capacity energy storage capacitor is mainly designed at a voltage input end and an output end. In order to prolong the power-down holding time of the power supply, a larger number of energy storage capacitors with larger capacity are generally designed at the input end or the output end. Increasing the number of storage capacitors would undoubtedly result in greater space being required; the energy storage capacitor with larger capacity is selected to occupy larger space because the volume of the energy storage capacitor is positively correlated with the electric quantity which can be stored. Thus, increasing the number or capacity of the storage capacitors results in a need to occupy more space.

With reference to fig. 1, a circuit for power converter power down retention, comprising: the power supply converter, the charging energy storage circuit and the ideal diode are connected in parallel and then connected in series with the power supply converter;

the power converter can convert the input power into output power with different voltages or currents to meet the requirements of different devices. The power converter is generally composed of a transformer, a rectifier, a filter, a voltage stabilizer and the like, and can realize the conversion of voltage reduction, voltage increase, rectification, inversion and the like of an input power supply. It is widely used in various fields of electronic equipment, communication, power, industrial automation and the like, and is an indispensable part of modern electronic equipment.

The working principle of the charging energy storage circuit is based on the law of conservation of energy, electric energy is converted into chemical energy through energy conversion and stored, and then the chemical energy is converted into electric energy through energy release and output. In the charging process, current flows to the energy storage element through the charging circuit, and electric energy is converted into chemical energy to be stored; during discharge, current flows from the energy storage element and powers the load through the power converter.

An ideal diode is an ideal electronic component with very low on-resistance, which is almost negligible. In the power converter, the ideal diode can effectively reduce the loss of the system and improve the efficiency of the power supply. When the system input voltage passes through the ideal diode, it produces a very small voltage drop because the on-resistance of the ideal diode is very low. This voltage drop does not have any effect on the operation of the system and does not generate any heat, so that no additional heat dissipation means are required. The greatest advantage of an ideal diode is its negligible on-resistance. This means that in a power converter the current through the ideal diode can pass completely without any energy loss. As a possible implementation, the ideal diode circuit may be designed with Metal Oxide Semiconductor Field Effect Transistors (MOSFETs), with on-resistances as low as a few mΩ, with little impact on system losses.

Specifically, the design and implementation manner of the charging energy storage circuit are various, and as one possible implementation manner, the charging energy storage circuit comprises an energy storage capacitor, a boost converter and a change-over switch, wherein the boost converter and the change-over switch are connected in series, one end of the energy storage capacitor is grounded, the other end of the energy storage capacitor is connected to the output end of the boost converter, and the change-over switch is conducted when the input voltage of an ideal diode is lower than the undervoltage limit value.

Since the boost converter does not participate in supplying power to the subsequent stage, no power is required, the design power is as small as possible to reduce the increase in system losses caused thereby. Since the capacitance energy of the storage capacitor is positively correlated with the input voltage (e=1/2×c×v ² E is energy, C is capacitance, V is voltage), and the power-down holding time and the capacitance energy are positively correlated, so that the boost converter can maximally reach the highest allowable working voltage of the power converter, and the energy storage potential of the capacitor can be furthest exerted when power is off, and the power-down holding time is greatly improved.

In addition, if longer power-off holding time is required, the capacity of the storage capacitor can be increased, the number of the storage capacitors can be increased, or a power converter with higher allowable input voltage can be selected.

Since most voltage converters are buck-type, the input voltage is higher than the output voltage and the current is smaller, so that the input end adopts a capacitor with higher rated voltage and smaller capacity, and the output end adopts a capacitor with lower rated voltage and larger capacity. By adopting the circuit for power-down holding of the power converter, which is provided by the embodiment of the disclosure, the charging energy storage circuit is arranged at the input end, and the voltage of the input energy storage capacitor is improved by the boost converter arranged in the charging energy storage circuit, so that the energy storage energy of the capacitor and the power-down holding time can be improved by square times of the whole circuit. The adoption of the disclosed embodiments can reduce the occupied space when the same power-down holding time is reached. At the same time, the influence on the efficiency and the loss of the converter is reduced to the minimum.

Optionally, the output end of the ideal diode is connected with the input end of the power converter. Therefore, the ideal diode can conduct the main circuit during normal power supply, and the normal operation of the power supply converter is ensured. And when the power is off, the power is in a reverse cut-off state, and the reverse voltage of the input end caused by the voltage of the energy storage capacitor is prevented.

Optionally, an input end of the ideal diode is connected with an input power supply, and the input power supply is a direct current power supply. Therefore, the ideal diode can conduct the voltage input by the system, and the normal operation of the power converter is ensured.

Optionally, the power converter is a direct current-direct current power converter (DC-DC converter). Such a power converter may convert a dc voltage from one level to another.

Optionally, the circuit further includes a first filter capacitor, one end of the first filter capacitor is grounded, and the other end of the first filter capacitor is connected between the input end of the power converter and the output end of the ideal diode. Therefore, the first filter capacitor can play a role of smoothing voltage in the circuit, absorb power voltage fluctuation and ripple waves, conduct alternating current, isolate direct current and ensure that an electric signal input into the direct current-direct current power converter is a direct current signal.

Optionally, the circuit further includes a second filter capacitor, one end of the second filter capacitor is grounded, and the other end of the second filter capacitor is connected to the output end of the power converter. Thus, the second filter capacitor has a similar function to the first filter capacitor, and is not described herein in detail, so as to ensure that the electric signal output by the dc-dc power converter is a dc signal.

Optionally, the power converter is a wide-voltage input power converter. Because the wide-voltage input power converter can tolerate higher input voltage and a wider allowable voltage range, the energy storage potential of the capacitor can be furthest exerted when the power converter is widely input into the power converter, and the power failure holding time is greatly prolonged.

Referring to fig. 1 specifically, for example, the system input voltage is 9-60V, the main channel ideal diode is conducted to supply power, and the power converter works to output 12V voltage. Meanwhile, the bypass boost converter starts to work, the 9-60V input voltage is boosted to 60V, and the energy storage capacitor is charged to 60V. The bypass switch is controlled by a main path ideal diode control or indication signal (e.g., power Good, etc.). If the main path voltage is normal, controlling the change-over switch to be in an off state; if the main path voltage falls below the normal voltage range, the change-over switch is turned on rapidly in us stage time. The energy storage capacitor takes over the input voltage to continuously supply power to the subsequent stage, and the initial power supply voltage is 60V. During the power supply period of the bypass energy storage capacitor, the ideal diode circuit is in a reverse cut-off state, and the voltage of the energy storage capacitor cannot reverse the voltage of the input end. And when the voltage of the energy storage capacitor is discharged from 60V to 9V, the post-stage power converter stops working, and the power-off maintaining time is finished.

The embodiment of the disclosure also provides a power supply device, which comprises the circuit for maintaining the power failure of the power supply converter. The circuit for power-down holding of the power converter is mounted to the power supply device. The mounting relationships described herein are not limited to placement within a product, but include mounting connections to other components of a product, including but not limited to physical, electrical, or signal transmission connections, etc. Those skilled in the art will appreciate that the circuitry for power converter power down retention may be adapted to a viable power supply apparatus to achieve other viable embodiments.

The above description and the drawings illustrate embodiments of the disclosure sufficiently to enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. Moreover, the terminology used in the present application is for the purpose of describing embodiments only and is not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a," "an," and "the" (the) are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this application is meant to encompass any and all possible combinations of one or more of the associated listed items. Furthermore, when used in this application, the terms "comprises," "comprising," and/or "includes," and variations thereof, mean that the stated features, integers, steps, operations, elements, and/or components are present, but that the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof is not precluded. Without further limitation, an element defined by the phrase "comprising one …" does not exclude the presence of other like elements in a process, method or apparatus comprising such elements. In this context, each embodiment may be described with emphasis on the differences from the other embodiments, and the same similar parts between the various embodiments may be referred to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method sections disclosed in the embodiments, the description of the method sections may be referred to for relevance.

Those of skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. The skilled artisan may use different methods for each particular application to achieve the described functionality, but such implementation should not be considered to be beyond the scope of the embodiments of the present disclosure. It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the embodiments disclosed herein, the disclosed methods, articles of manufacture (including but not limited to devices, apparatuses, etc.) may be practiced in other ways. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the units may be merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. In addition, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interface, device or unit indirect coupling or communication connection, which may be in electrical, mechanical or other form. The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to implement the present embodiment. In addition, each functional unit in the embodiments of the present disclosure may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In the description corresponding to the flowcharts and block diagrams in the figures, operations or steps corresponding to different blocks may also occur in different orders than that disclosed in the description, and sometimes no specific order exists between different operations or steps. For example, two consecutive operations or steps may actually be performed substantially in parallel, they may sometimes be performed in reverse order, which may be dependent on the functions involved. Each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

Claims (8)

1. A circuit for power converter power down retention, comprising: the power supply converter, the charging energy storage circuit and the ideal diode are connected in parallel and then connected in series with the power supply converter;

the charging energy storage circuit comprises an energy storage capacitor, a boost converter and a change-over switch, wherein the boost converter and the change-over switch are connected in series, one end of the energy storage capacitor is grounded, the other end of the energy storage capacitor is connected with the output end of the boost converter, and the change-over switch is conducted when the input voltage of the ideal diode is lower than the undervoltage limit value.

2. The circuit of claim 1, wherein the output of the ideal diode is connected to the input of the power converter.

3. The circuit of claim 1, wherein the input terminal of the ideal diode is connected to an input power source, the input power source being a dc power source.

4. The circuit of claim 1, wherein the power converter is a dc-dc power converter.

5. The circuit of claim 4, further comprising a first filter capacitor having one end connected to ground and the other end connected between the input of the power converter and the output of the ideal diode.

6. The circuit of claim 4, further comprising a second filter capacitor, one end of the second filter capacitor being connected to ground, the other end of the second filter capacitor being connected to the output of the power converter.

7. The circuit of claim 1, wherein the power converter is a wide voltage input power converter.

8. A power supply apparatus comprising the circuit for power-down holding of a power converter according to any one of claims 1 to 7.