An automatically tracking DC regulated power supply and method of use

Abstract

This invention belongs to the field of voltage regulator technology, specifically relating to an automatic tracking DC voltage regulator and its usage method, comprising a switching voltage regulator, a voltage follower circuit, a series voltage regulator, and a load connected in sequence; the output terminal of the switching voltage regulator is connected to the input terminal of the series voltage regulator; the voltage follower circuit includes a first resistor, a second resistor, a third resistor, and a first thyristor; one end of the first capacitor is connected to the output terminal of the switching voltage regulator, and the other end is connected to the emitter of the first thyristor; the collector of the first thyristor is connected to the voltage feedback terminal of the switching voltage regulator; the two ends of the second resistor are respectively connected to the output terminal of the switching voltage regulator and the base of the first thyristor; the two ends of the third resistor are respectively connected to the base of the first thyristor and the output terminal of the series voltage regulator; the two ends of the adjusting potentiometer are respectively connected to the voltage feedback terminal of the series voltage regulator and the output terminal of the series voltage regulator.

Description

Technical Field

[0001] This invention belongs to the field of voltage regulator technology, specifically relating to an automatic tracking DC voltage regulator and its usage method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] A DC regulated power supply is an electronic device that provides a stable DC power supply to a load. Most DC regulated power supplies are powered by AC power, and the DC output voltage of the regulator remains stable even when the voltage of the AC power supply or the load resistance changes. As electronic equipment develops towards higher precision, higher stability, and higher reliability, higher requirements are placed on the power supplies for these devices.

[0004] DC regulated power supplies are broadly classified into two categories: switching power supplies and series power supplies. Switching power supplies are generally used in high-current applications because their regulating components operate in a switching state. They can operate with high efficiency when the load current is large, and they have the characteristics of low self-loss and small size. However, their output voltage adjustment range is relatively small. When extremely low output voltage is required, switching power supplies operate in a "hiccup" mode, resulting in large output ripple. Series DC regulated power supplies typically use high-power transistors or MOSFETs as regulating components. The regulating transistor is connected in series with the load, and the portion of the load power other than that used is dissipated as heat through the regulating transistor. Typically, the regulating transistor requires a large metal heat sink and cooling fan.

[0005] According to the inventor, the output current of a series-type DC regulated power supply is generally not large. When the required output voltage range is large, it is usually necessary to switch the input voltage of the series-type DC regulated power supply in stages using relays and multi-tap transformers. During the switching process, the output voltage will drop due to the effect of the switching response time. Existing series-type DC regulated power supplies are relatively stable when the output voltage is low, but they have the disadvantages of large size and heavy weight. Summary of the Invention

[0006] To address the aforementioned issues, this invention proposes an automatic tracking DC regulated power supply and its usage method. It combines a switching power supply with a series-type DC regulated power supply, using the output of the switching power supply as the input of the series-type power supply. When the output voltage is adjusted, the voltage of the switching power supply follows the output voltage adjustment, ensuring that the voltage difference between the collector and emitter of the series-type power supply remains at a fixed value, thus reducing losses.

[0007] According to some embodiments, the first aspect of the present invention provides an automatically tracking DC regulated power supply, employing the following technical solution:

[0008] An automatically tracking DC regulated power supply includes a switching power supply, a voltage follower circuit, a series power supply, and a load connected in sequence. The output terminal of the switching power supply is connected to the input terminal of the series power supply. The voltage follower circuit includes a first resistor, a second resistor, a third resistor, and a first thyristor. One end of the first capacitor is connected to the output terminal of the switching power supply, and the other end is connected to the emitter of the first thyristor. The collector of the first thyristor is connected to the voltage feedback terminal of the switching power supply. One end of the second resistor is connected to the output terminal of the switching power supply, and the other end is connected to the base of the first thyristor. One end of the third resistor is connected to the base of the first thyristor, and the other end is connected to the output terminal of the series power supply. The output terminal of the series power supply is connected to the load and one end of an adjustment potentiometer, and the other end of the adjustment potentiometer is connected to the voltage feedback terminal of the series power supply.

[0009] As a further technical limitation, the output voltage of the series-type regulated power supply increases as the connection resistance of the adjustment potentiometer increases.

[0010] As a further technical limitation, the voltage follower circuit also includes a fourth resistor, one end of which is connected to the collector of the first thyristor, and the other end is grounded.

[0011] Furthermore, the output voltage of the switching power supply is adjusted according to the values ​​of the second and third resistors, so that the first thyristor is in an amplification state; when the input resistance of the adjusting potentiometer changes, the base current of the first thyristor changes, and the output voltage of the switching power supply changes.

[0012] As a further technical limitation, the voltage follower circuit also includes a first capacitor, which is connected in parallel between the output terminal and the voltage feedback terminal of the switching power supply.

[0013] As a further technical limitation, a second capacitor is also connected to the output terminal of the series-type regulated power supply, and the other end of the second capacitor is grounded.

[0014] As a further technical limitation, a fifth resistor is also connected to the voltage feedback terminal of the series-type regulated power supply, and the other end of the fifth resistor is grounded.

[0015] As a further technical limitation, the first thyristor is a PNP type transistor or an NPN type transistor.

[0016] According to some embodiments, the second aspect of the present invention provides a method for using an automatically tracking DC regulated power supply, which employs the automatically tracking DC regulated power supply of the first aspect, and adopts the following technical solution:

[0017] A method for using an automatically tracking DC regulated power supply, wherein the output of a series-type regulated power supply is used as the output of the automatically tracking DC regulated power supply, and the input of a switching power supply is used as the input of the automatically tracking DC regulated power supply; when the output voltage of the automatically tracking DC regulated power supply is increased, the output voltage of the switching power supply is increased accordingly; when the output voltage of the automatically tracking DC regulated power supply is decreased, the output voltage of the switching power supply is decreased accordingly.

[0018] As a further technical limitation, the output voltage of the switching power supply is adjusted according to the values ​​of the second and third resistors, so that the first thyristor is in the amplification state; when the connection resistance of the potentiometer is adjusted, the base current of the first thyristor and the output voltage of the switching power supply both change.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] This invention significantly reduces the voltage difference between the input and output of the series-type regulated power supply in the output stage. When the output current is large, it significantly reduces the losses caused by the output stage operating in amplification mode. When the output circuit is low, the input stage switching power supply does not need to be adjusted to a lower voltage. When the output voltage changes, the voltage difference of the regulating transistor in the series-type regulated power supply in the output stage does not change. The automatic tracking DC regulated power supply in this invention has high voltage conversion efficiency and low output ripple voltage. Attached Figure Description

[0021] The accompanying drawings, which form part of this embodiment, are used to provide a further understanding of this embodiment. The illustrative embodiments and their descriptions are used to explain this embodiment and do not constitute an improper limitation of this embodiment.

[0022] Figure 1 This is a schematic diagram of the principle of the automatically tracking DC regulated power supply in Embodiment 1 of the present invention. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] In this invention, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only to facilitate the description of the structural relationships of the various components or elements of this invention and do not specifically refer to any component or element in this invention. They should not be construed as limiting the invention.

[0027] In this invention, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0028] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0029] Example 1

[0030] Embodiment 1 of the present invention introduces an automatic tracking DC regulated power supply.

[0031] like Figure 1 The diagram shows an automatic tracking DC regulated power supply, bounded by a dotted line, comprising a switching power supply, a voltage follower circuit, a series power supply, and a load connected in sequence; the output terminal of the switching power supply is connected to the input terminal of the series power supply.

[0032] The voltage follower circuit includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a first capacitor C1, and a first thyristor Q1. One end of the first capacitor C1 is connected to the output terminal of the switching power supply, and the other end is connected to the emitter of the first thyristor Q1. The collector of the first thyristor Q1 is connected to the voltage feedback terminal of the switching power supply. One end of the second resistor R2 is connected to the output terminal of the switching power supply, and the other end is connected to the base of the first thyristor Q1. One end of the third resistor R3 is connected to the base of the first thyristor Q1, and the other end is connected to the output terminal of the series-type power supply.

[0033] The output terminal of the series-type regulated power supply is connected to the load LOAD and one end of the adjustment potentiometer RP respectively. The other end of the adjustment potentiometer RP is connected to the voltage feedback terminal of the series-type regulated power supply. One end of the fourth resistor R4 is connected to the collector of the first thyristor Q1, and the other end is grounded. The first capacitor C1 is connected in parallel between the output terminal and the voltage feedback terminal of the switching power supply.

[0034] The output terminal of the series-type regulated power supply is also connected to a second capacitor C2, the other end of which is grounded; the voltage feedback terminal of the series-type regulated power supply is also connected to a fifth resistor R5, the other end of which is grounded; the output voltage of the series-type regulated power supply increases as the resistance of the potentiometer RP increases.

[0035] Based on the resistance values ​​of the second resistor R2 and the third resistor R3, the output voltage of the switching power supply is set to a higher value than that of the linear power supply. This ensures that the regulating transistor of the linear power supply is in the amplification state, and the first thyristor Q1 exhibits variable resistance characteristics. When the output voltage of the adjusting potentiometer RP is adjusted, the current flowing from the base of the first thyristor Q1 (control current) changes accordingly. When the output voltage is adjusted from large to small, the current flowing from the base of the first thyristor Q1 increases from small to large, and the resistance value of the variable resistance characteristic of the first thyristor Q1 decreases. According to the output voltage adjustment formula, the output voltage of the switching power supply... That is, as the equivalent resistance RQ1 of the first thyristor Q1 decreases, the Vout voltage decreases; where Vfb is the output voltage of the voltage feedback terminal of the switching power supply.

[0036] In this embodiment, the fourth resistor R4 is the lower bias resistor of the feedback network of the switching power supply; the typical value of the output voltage Vfb at the voltage feedback terminal of the switching power supply is 0.8V, 1V, or 1.2V. In this embodiment, Vfb = 0.8V is chosen. R4 and Vfb determine the emitter current value of the first thyristor Q1, and the emitter current is...

[0037] In this embodiment, the first thyristor Q1 is either a PNP or NPN transistor. The NPN thyristor operates in amplification mode, with a voltage difference of approximately 2.5V between its collector and emitter. This difference varies slightly depending on the transistor model and load current; in this embodiment, it is 2.7V. In the PNP thyristor, the voltage difference Vbe between the base and emitter is 0.7V, and the voltage across the second resistor R2 is... When R2 = R3, the voltage difference between the collector and emitter of the output stage series-type Zener diode is:

[0038] In this embodiment, the components with the specifications shown in Table 1 are used. The Vbe voltage of the first thyristor Q1 is measured to be 0.705V using a multimeter, and the resistance of the first resistor R1 is 1.72K. When the output voltage is adjusted to 0V, the output voltage of the switching power supply is measured to be 2.72V. The output voltage is adjusted from 0V to 18V. Throughout the entire range, the output voltage of the switching power supply is always about 2.7V higher than the output voltage.

[0039] Table 1 Specifications of Components

[0040] Reference number Specification Reference number Specification R1 1.8KΩ±1% Q1 MMBT3906 R2 100KΩ±1% C1 1nF R3 100KΩ±1% RP 10KΩ±1%

[0041] This invention combines the characteristics of switching power supplies and linear regulated power supplies, enabling the power supply to have a large adjustment range, supporting adjustment to 0V, and maintaining high efficiency throughout the adjustment range. Switching power supplies have high efficiency, but high ripple voltage and a small adjustable output voltage range, especially at extremely low output voltages. Linear regulated power supplies have high output voltage accuracy and low ripple voltage, but extremely low efficiency, especially at low output voltages where efficiency is less than 10%. This circuit combines all the advantages of switching power supplies and series regulated power supplies, featuring high efficiency, low ripple, and high voltage regulation accuracy.

[0042] Example 2

[0043] Embodiment 2 of the present invention introduces a method for using an automatically tracking DC regulated power supply.

[0044] A method for using an automatically tracking DC regulated power supply, wherein the output of a series-type regulated power supply is used as the output of the automatically tracking DC regulated power supply, and the input of a switching power supply is used as the input of the automatically tracking DC regulated power supply; when the output voltage of the automatically tracking DC regulated power supply is increased, the output voltage of the switching power supply is increased accordingly; when the output voltage of the automatically tracking DC regulated power supply is decreased, the output voltage of the switching power supply is decreased accordingly.

[0045] As one or more embodiments, the output voltage of the switching power supply is adjusted according to the values ​​of the second resistor and the third resistor, so that the first thyristor is in an amplification state; when the connection resistance of the potentiometer is adjusted, the base current of the first thyristor and the output voltage of the switching power supply both change.

[0046] The detailed steps are the same as the working principle of the automatically tracking DC regulated power supply provided in Example 1, and will not be repeated here.

[0047] The above description is merely a preferred embodiment of this practice and is not intended to limit the scope of this practice. Various modifications and variations can be made to this practice by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this practice should be included within the protection scope of this practice.

Claims

1. An automatically tracking DC regulated power supply, characterized in that, The system comprises a switching power supply, a voltage follower circuit, a series power supply, and a load connected in sequence. The output of the switching power supply is connected to the input of the series power supply. The voltage follower circuit includes a first resistor, a second resistor, a third resistor, a first capacitor, and a first thyristor. The first thyristor is a PNP or NPN transistor. One end of the first capacitor is connected to the output of the switching power supply, and the other end is connected to the emitter of the first thyristor. The collector of the first thyristor is connected to the voltage feedback terminal of the switching power supply. One end of the second resistor is connected to the output of the switching power supply, and the other end is connected to the base of the first thyristor. One end of the third resistor is connected to the base of the first thyristor, and the other end is connected to the output of the series power supply. The output of the series power supply is connected to the load and one fixed terminal of an adjustment potentiometer. The sliding terminal of the adjustment potentiometer is connected to the voltage feedback terminal of the series power supply, and the other fixed terminal of the adjustment potentiometer is connected to the sliding terminal.

2. The automatically tracking DC regulated power supply as described in claim 1, characterized in that, The output voltage of the series-type regulated power supply increases as the input resistance of the adjusting potentiometer increases.

3. The automatically tracking DC regulated power supply as described in claim 1, characterized in that, The voltage follower circuit also includes a fourth resistor, one end of which is connected to the collector of the first thyristor, and the other end is grounded.

4. The automatically tracking DC regulated power supply as described in claim 3, characterized in that, The output voltage of the switching power supply is adjusted according to the values ​​of the second and third resistors, so that the first thyristor is in an amplification state; when the input resistance of the adjusting potentiometer changes, the base current of the first thyristor changes, and the output voltage of the switching power supply changes.

5. The automatically tracking DC regulated power supply as described in claim 1, characterized in that, The first capacitor is connected in parallel between the output terminal and the voltage feedback terminal of the switching power supply.

6. The automatically tracking DC regulated power supply as described in claim 1, characterized in that, A second capacitor is also connected to the output terminal of the series-type regulated power supply, and the other end of the second capacitor is grounded.

7. The automatically tracking DC regulated power supply as described in claim 1, characterized in that, A fifth resistor is also connected to the voltage feedback terminal of the series-type regulated power supply, and the other end of the fifth resistor is grounded.

8. A method of using an automatically tracking DC regulated power supply, comprising the automatically tracking DC regulated power supply as described in any one of claims 1-7, characterized in that, The output of the series-type regulated power supply is used as the output of the automatic tracking DC regulated power supply, and the input of the switching power supply is used as the input of the automatic tracking DC regulated power supply. When the output voltage of the automatic tracking DC regulated power supply is increased, the output voltage of the switching power supply is increased accordingly; when the output voltage of the automatic tracking DC regulated power supply is decreased, the output voltage of the switching power supply is decreased accordingly.

9. The method of using an automatically tracking DC regulated power supply as described in claim 8, characterized in that, The output voltage of the switching power supply is adjusted according to the values ​​of the second and third resistors, so that the first thyristor is in the amplification state; when the connection resistance of the potentiometer is adjusted, the base current of the first thyristor and the output voltage of the switching power supply both change.

Images