Low-ripple high-power hybrid power supply

Abstract

An input power supply is respectively connected with a bidirectional direct-current power supply and a direct-current switching power supply, the bidirectional direct-current power supply is respectively connected with a user load and a linear voltage-stabilized power supply, the output end of the direct-current switching power supply is connected with the linear voltage-stabilized power supply, and the output end of the linear voltage-stabilized power supply is connected with the user load. The linear voltage-stabilized power supply comprises an operational amplifier and a field-effect tube, the positive-phase input end of the operational amplifier is connected with external reference voltage, the drain electrode of the field-effect tube is connected with the direct-current switching power supply, the grid electrode of the field-effect tube is connected with the vertex angle output end of the operational amplifier, and the source electrode of the field-effect tube is connected with a user load. The output end of the linear voltage-stabilized power supply is connected with a user load, the output end of the bidirectional direct-current power supply is connected with the inverted input end of an operational amplifier of the linear voltage-stabilized power supply, the bidirectional direct-current power supply is connected with the user load, the output end of the direct-current switching power supply is connected with the drain electrode of a field-effect tube of the linear voltage-stabilized power supply, and the direct-current switching power supply is grounded.

Description

TECHNICAL FIELD

[0001] The utility model relates to high -performance intelligentized instrument and meter technical field, more specifically, relate to a low ripple high -power hybrid power supply. BACKGROUND

[0002] Traditional switching power supply can provide high power output, switching power supply adjusts output voltage or current through high frequency switch, this process introduces rapidly changing current and voltage, causes the ripple to appear at the output end. Although can alleviate the ripple by increasing the filter component, this will increase the cost, volume and weight, and the effect of reducing electromagnetic interference (EMI) is limited.

[0003] On the other hand, linear power supply is known for its extremely low output ripple, suitable for application occasions requiring high precision and stability, however, the working mode of linear power supply is to dissipate a large amount of energy on the adjusting element to accurately control the output voltage, which not only is inefficient, but also causes significant heating problem when dealing with high power, therefore, linear power supply often appears to be inadequate when facing high power demand because of high power consumption and heat dissipation difficulty.

[0004] As a method to solve the above problems, multiphase interleaving technology tries to reduce the output ripple as much as possible while maintaining high efficiency and high power output, this technology disperses load current, smooths output current waveform, reduces total output ripple amplitude, and relieves the pressure of input filter by connecting multiple independent switching converters in parallel and making them work in different phases. Despite this, multiphase interleaving technology still cannot completely eliminate the output ripple, especially in extreme high power application scenarios, it is still a challenge to achieve ideal low ripple performance at the same time.

[0005] Therefore, the existing power supply technology often has to sacrifice the output ripple performance to some extent when pursuing high power output, and vice versa. This trade-off reflects a core contradiction in current power supply design: it is difficult to achieve high efficiency and high power output and extremely low output ripple at the same time in the same power supply system. SUMMARY

[0006] In order to solve the problem of simultaneously achieving high efficiency and high power output and extremely low output ripple, the utility model provides a low ripple high power hybrid power supply.

[0007] The utility model technical scheme is as follows:

[0008] A low ripple high power hybrid power supply, comprising a bidirectional DC power supply, a DC switching power supply and a linear voltage regulator, an input power supply is connected to the bidirectional DC power supply and the DC switching power supply,

[0009] The bidirectional DC power source is connected with the user load and the linear voltage regulator respectively, the output end of the DC switching power source is connected with the linear voltage regulator, and the output end of the linear voltage regulator is connected with the user load,

[0010] The linear voltage regulator comprises an operational amplifier and a field effect transistor,

[0011] The positive input end of the operational amplifier is connected with an external reference voltage, the drain of the field effect transistor is connected with the DC switching power source, the gate of the field effect transistor is connected with the top corner output end of the operational amplifier, the source of the field effect transistor is connected with the user load, and the output end of the linear voltage regulator is connected with the user load,

[0012] The output end of the bidirectional DC power source is connected with the inverting input end of the operational amplifier of the linear voltage regulator, and the bidirectional DC power source is connected with the user load,

[0013] The output end of the DC switching power source is connected with the drain of the field effect transistor of the linear voltage regulator, and the DC switching power source is grounded.

[0014] The low-ripple high-power hybrid power source has the following characteristics: when the hybrid power source circuit is normally working, the output end voltage of the DC switching power source is greater than the output end voltage of the linear voltage regulator.

[0015] Further, the factors considered between the output end voltage of the DC switching power source and the output end voltage of the linear voltage regulator include:

[0016] (1) minimum voltage difference, according to the minimum voltage difference required for the normal working of the linear voltage regulator;

[0017] (2) ripple, according to the expected ripple amplitude voltage difference margin;

[0018] (3) dynamic load, according to the change of the user load to increase the additional voltage difference;

[0019] (4) thermal management, reasonably control the heat consumption of the linear voltage regulator.

[0020] Further, the voltage difference amount of the dynamic load and the thermal management of the linear voltage regulator is a preset value, which satisfies

[0021] [(output end voltage of the DC switching power source-output end voltage of the linear voltage regulator) / output end voltage of the linear voltage regulator]∈[1%, 5%].

[0022] The low-ripple high-power hybrid power source has the following characteristics: when the hybrid power source circuit is normally working, the output end voltage of the bidirectional DC power source is less than the output end voltage of the linear voltage regulator, the reference voltage is less than the output end voltage of the linear voltage regulator, and the bidirectional DC power source is in a constant current load state.

[0023] Further, when the state of the DC switching power supply or the state of the user load causes the output voltage of the linear voltage regulator to be less than the set target value, the linear voltage regulator increases the conduction degree or suspends the regulation action, and the bidirectional DC power supply supplies power to the user load, so that the output voltage of the linear voltage regulator is restored.

[0024] Further, when the state of the DC switching power supply or the state of the user load causes the output voltage of the linear voltage regulator to be less than the set target value, the linear voltage regulator increases the conduction degree or suspends the regulation action, and the bidirectional DC power supply supplies power to the user load, so that the output voltage of the linear voltage regulator is restored.

[0025] According to the above-mentioned scheme, the beneficial effects are that the switching power supply provides high-efficiency large-power output, the linear voltage regulator ensures low ripple and stability of the output voltage, the bidirectional DC power supply almost does not consume power in the normal state, and as a backup power supply, provides adjustment in the burst state. When the user load suddenly increases, causing the output voltage of the linear voltage regulator to decrease, the bidirectional DC power supply quickly switches to the source state, supplies additional current to the user load, and restores the output voltage of the linear voltage regulator to the set value. At the same time, the linear voltage regulator continues to absorb the ripple from the DC switching power supply, ensuring the output quality. When the user load suddenly decreases or other reasons cause the output voltage of the linear voltage regulator to rise, the bidirectional DC power supply increases the feedback current, quickly pulls down the output voltage of the linear voltage regulator, maintains the stability of the output voltage of the hybrid power supply, and protects the circuit connected to the hybrid power supply from being affected by the high voltage. If the pressure difference between the linear voltage regulator and the bidirectional DC power supply is too large (for example, due to sharp changes in the user load), the bidirectional DC power supply can control the linear voltage regulator to shut down, avoiding damage due to overheating or overloading. Through the cooperative control and mutual cooperation design among the three power supplies, the hybrid power supply not only can efficiently provide large-power output, ensure that the output voltage has extremely low ripple, and has high stability and smoothness, but also can quickly respond to changes in the user load, enhance the transient response capability of the hybrid power supply, and improve the reliability and performance of the entire power supply system. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor.

[0027] Figure 1 The figure is a structural schematic diagram of the hybrid power supply of the present application. DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects of the utility model clearer and more apparent, the utility model will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the utility model and not to limit the utility model.

[0029] A low-ripple high-power hybrid power supply, as shown in Figure 1 includes a bidirectional DC power supply, a DC switching power supply and a linear voltage regulator, the input power supply is connected to the bidirectional DC power supply and the DC switching power supply, the bidirectional DC power supply is connected to the user load and the linear voltage regulator, the output end of the DC switching power supply is connected to the linear voltage regulator, the output end of the linear voltage regulator is connected to the user load, the linear voltage regulator includes an operational amplifier and a field effect tube, the positive input end of the operational amplifier is connected to an external reference voltage, the drain of the field effect tube is connected to the DC switching power supply, the gate of the field effect tube is connected to the top corner output end of the operational amplifier, the source of the field effect tube is connected to the user load, the output end of the linear voltage regulator is connected to the user load, the output end of the bidirectional DC power supply is connected to the inverting input end of the operational amplifier of the linear voltage regulator, the bidirectional DC power supply is connected to the user load, the output end of the DC switching power supply is connected to the drain of the field effect tube of the linear voltage regulator, and the DC switching power supply is grounded.

[0030] When the hybrid power supply circuit is working normally, the output end voltage of the DC switching power supply is greater than the output end voltage of the linear voltage regulator.

[0031] The factors considered between the output end voltage of the DC switching power supply and the output end voltage of the linear voltage regulator include:

[0032] (1) minimum voltage difference, according to the minimum voltage difference required for the normal operation of the linear voltage regulator;

[0033] (2) ripple, according to the expected ripple amplitude voltage difference margin;

[0034] (3) dynamic load, according to the change of the user load to increase the additional voltage difference;

[0035] (4) thermal management, reasonable control of the heat consumption of the linear voltage regulator.

[0036] The output end voltage of the linear voltage regulator is also the output end voltage of the entire circuit of the hybrid power supply, and the output end voltage of the linear voltage regulator is also the user voltage.

[0037] The output voltage of the DC switching power supply is greater than the output voltage of the linear voltage regulator. Since the linear voltage regulator maintains the stability of the output voltage by adjusting the conduction degree of the internal transistor, the input voltage of the linear voltage regulator (i.e. the output voltage of the DC switching power supply) needs to be higher than the output voltage of the linear voltage regulator to provide sufficient voltage difference for the linear voltage regulator to work normally, and there is a minimum voltage difference between them. Different linear voltage regulators have different working state requirements, such as the minimum voltage difference required by the LDO regulator is usually between tens of millivolts to hundreds of millivolts, and the minimum voltage difference required by some high-performance LDO regulator is only 50 millivolts. In order to ensure the normal work of the linear voltage regulator, the voltage difference between the output voltage of the DC switching power supply and the output voltage of the linear voltage regulator is at least greater than 50 millivolts.

[0038] The output voltage of the DC switching power supply has a ripple component, in order to ensure that the linear voltage regulator can effectively absorb these ripples and maintain the stability of the output, the voltage difference between the output voltage of the hybrid power supply (i.e. the output voltage of the linear voltage regulator) and the output voltage of the DC power supply should be greater than the minimum voltage difference requirement, and a margin is needed. The specific voltage difference amount for the ripple should consider the ripple amplitude, and this part of the voltage difference amount should at least meet the following formula: ripple amplitude / linear voltage regulator output voltage = DC switching power supply output voltage / linear voltage regulator output voltage.

[0039] In actual application, the user load may change, in order to ensure that the hybrid power supply can work normally under any state of the user load, the voltage difference between the linear voltage regulator and the DC switching power supply needs to be appropriately increased. In addition, the working mode of the linear voltage regulator is to dissipate the excess voltage in the form of heat through the transistor, therefore, the greater the voltage difference between the input voltage and the output voltage of the linear voltage regulator, the more energy the linear voltage regulator needs to consume, which will result in more heat generation and higher power consumption. The voltage difference amount for the dynamic load and thermal management of the linear voltage regulator is a preset value, which satisfies

[0040] [(DC switching power supply output voltage-linear voltage regulator output voltage) / linear voltage regulator output voltage] ∈ [1%, 5%].

[0041] When the hybrid power supply circuit is working normally, the output voltage of the bidirectional DC power supply is less than the output voltage of the linear voltage regulator, the reference voltage is less than the output voltage of the linear voltage regulator, and the bidirectional DC power supply is in a constant current load state.

[0042] When the reference voltage is lower than the output voltage of the linear voltage regulator, the bidirectional DC power supply is in a load state, and the bidirectional DC power supply absorbs current from the user load instead of providing current to the user load, so that the bidirectional DC power supply can quickly respond to load changes when needed, without causing additional burden to the hybrid power supply as a whole, and almost no power is consumed. When the user load changes, the bidirectional DC power supply can quickly remove excess charge from the user load and quickly provide charge to the user load.

[0043] In the normal state of the user load, the bidirectional DC power supply is in a stable and constant current load state. The normal state of the bidirectional DC power supply is a small stable and constant current load state, so that the bidirectional DC power supply is always in a ready state and can quickly respond to dynamic changes in the user load. Whether the load size of the user load increases or decreases, the bidirectional DC power supply can quickly mobilize the charge and transmit the state of the user load to the linear voltage regulator to maintain the stability of the output voltage of the linear voltage regulator.

[0044] When the state of the DC switching power supply or the user load causes the output voltage of the linear voltage regulator to be less than the set target value, the linear voltage regulator increases the conduction degree or suspends the adjustment action, and the bidirectional DC power supply supplies power to the user load, so that the output voltage of the linear voltage regulator rises.

[0045] When the state of the DC switching power supply and the user load is abnormal, such as a sudden drop in the output voltage of the DC switching power supply or a sudden increase in the user load, the output voltage of the linear voltage regulator decreases, or even lower than the reference voltage.

[0046] When the output voltage of the linear voltage regulator decreases to less than the set target value (the linear voltage regulator adjusts the output voltage by adjusting the internal transistor, i.e. the field effect transistor, to keep it near the set value, which is the set target value, and the value has an upper and lower limit), the linear voltage regulator quickly changes the adjustment action, increases the conduction degree, and increases the output current to help the output voltage of the linear voltage regulator recover above the set target value. The bidirectional DC power supply is in a dynamic stable and constant current load state for a long time, so it can quickly change and quickly provide power (voltage increase) to the user load, and the charge quickly flows to the user load. In this process, the user voltage (voltage at the user load) quickly increases, preventing the output voltage of the linear voltage regulator from decreasing for a long time, and stabilizing the output voltage of the linear voltage regulator.

[0047] When the output voltage of the linear voltage regulator is lower than the reference voltage, the voltage difference between the output voltage of the DC switching power supply and the output voltage of the linear voltage regulator becomes very small, or even close to zero or negative, causing the linear voltage regulator to fail to work normally, because it does not have enough voltage drop to maintain the stability of the output voltage. The linear voltage regulator starts the over-voltage protection (to avoid entering an unstable state), automatically closes the internal regulating element, stops the current regulating function, reduces the power consumption of the linear voltage regulator, prevents the linear voltage regulator from being damaged due to excessive power consumption or overheating, and also avoids the device connected to the hybrid power supply from entering an unstable state, protecting the device components from damage. The linear voltage regulator suspends the regulating action, and the bidirectional DC power supply absorbs current from the large user load and directly provides power to the user load, helping the output voltage of the linear voltage regulator to rise, and in a relatively short time, the rapid rise of the user voltage restores the voltage difference of the linear voltage regulator to normal, and the linear voltage regulator resumes the regulating action, and the linear voltage regulator resumes normal operation.

[0048] When the output voltage of the linear voltage regulator is lower than the reference voltage, the voltage difference between the output voltage of the DC switching power supply and the output voltage of the linear voltage regulator becomes very small, or even close to zero or negative, causing the linear voltage regulator to fail to work normally, because it does not have enough voltage drop to maintain the stability of the output voltage. The linear voltage regulator starts the over-voltage protection (to avoid entering an unstable state), automatically closes the internal regulating element, stops the current regulating function, reduces the power consumption of the linear voltage regulator, prevents the linear voltage regulator from being damaged due to excessive power consumption or overheating, and also avoids the device connected to the hybrid power supply from entering an unstable state, protecting the device components from damage. The linear voltage regulator suspends the regulating action, and the bidirectional DC power supply absorbs current from the large user load and directly provides power to the user load, helping the output voltage of the linear voltage regulator to rise, and in a relatively short time, the rapid rise of the user voltage restores the voltage difference of the linear voltage regulator to normal, and the linear voltage regulator resumes the regulating action, and the linear voltage regulator resumes normal operation.

[0049] When the output voltage of the linear voltage regulator is lower than the reference voltage, the voltage difference between the output voltage of the DC switching power supply and the output voltage of the linear voltage regulator becomes very small, or even close to zero or negative, causing the linear voltage regulator to fail to work normally, because it does not have enough voltage drop to maintain the stability of the output voltage. The linear voltage regulator starts the over-voltage protection (to avoid entering an unstable state), automatically closes the internal regulating element, stops the current regulating function, reduces the power consumption of the linear voltage regulator, prevents the linear voltage regulator from being damaged due to excessive power consumption or overheating, and also avoids the device connected to the hybrid power supply from entering an unstable state, protecting the device components from damage. The linear voltage regulator suspends the regulating action, and the bidirectional DC power supply absorbs current from the large user load and directly provides power to the user load, helping the output voltage of the linear voltage regulator to rise, and in a relatively short time, the rapid rise of the user voltage restores the voltage difference of the linear voltage regulator to normal, and the linear voltage regulator resumes the regulating action, and the linear voltage regulator resumes normal operation.

[0050] At this time, the bidirectional DC power supply can quickly change and increase the power supply current to the user load due to the long-term dynamic voltage stabilization and constant current load state, and can effectively absorb the excess charge at the user load by increasing the current output, thereby quickly reducing the output voltage of the linear voltage stabilizer to return to the set target value. Through the rapid response of the bidirectional DC power supply, the output voltage of the linear voltage stabilizer will quickly decrease and return to the set target value, which helps to prevent the output voltage of the linear voltage stabilizer from exceeding the set value for a long time, and ensures the stability and reliability of the overall hybrid power supply and the system or device connected thereto. If the output voltage of the linear voltage stabilizer is higher than the set target value for a period of time, the pressure difference between the input voltage and the output voltage of the linear voltage stabilizer is too large (i.e. the pressure difference between the output voltage of the DC switching power supply and the output voltage of the linear voltage stabilizer is too large), and the linear voltage stabilizer may enter an overheating or overload state. Through the intervention of the bidirectional DC power supply, the output voltage of the linear voltage stabilizer can be effectively reduced to avoid damage to the linear voltage stabilizer due to excessive pressure difference. At the same time, the linear voltage stabilizer will adjust its conduction degree and reduce the conduction degree to reduce its output voltage. The cooperative work of the bidirectional DC power supply and the linear voltage stabilizer can ensure the stability and reliability of the output voltage of the hybrid power supply even in the case of sudden changes in user load or external interference.

[0051] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A low-ripple high-power hybrid power supply, characterized by, The linear voltage regulator includes an operational amplifier and a field effect transistor, 2. A low-ripple high-power hybrid power supply as defined in claim 1, characterized in that The positive input terminal of the operational amplifier is connected to the external reference voltage, the drain of the field effect transistor is connected to the DC switching power supply, the gate of the field effect transistor is connected to the top corner output terminal of the operational amplifier, the source of the field effect transistor is connected to the user load, and the output terminal of the linear voltage regulator is connected to the user load, The output terminal of the bidirectional DC power supply is connected to the inverting input terminal of the operational amplifier of the linear voltage regulator, and the bidirectional DC power supply is connected to the user load, The output terminal of the DC switching power supply is connected to the drain of the field effect transistor of the linear voltage regulator. The output terminal voltage of the DC switching power supply is greater than the output terminal voltage of the linear voltage regulator.

3. A low-ripple high-power hybrid power supply as defined in claim 1, characterized in that The output terminal voltage of the bidirectional DC power supply is less than the output terminal voltage of the linear voltage regulator, and the reference voltage is less than the output terminal voltage of the linear voltage regulator.

4. A low-ripple high-power hybrid power supply as defined in claim 1, characterized in that [(output terminal voltage of the DC switching power supply - output terminal voltage of the linear voltage regulator) / output terminal voltage of the linear voltage regulator] ∈ [1%, 5%].

5. A low-ripple high-power hybrid power supply as defined in claim 1, wherein ​

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