Power supply circuit and control method with temporary power supply and charge / discharge control functions

Abstract

This invention discloses a power supply circuit with temporary power supply and charge / discharge control functions, located between a DC power source and a load. It includes a capacitor, a current-limiting charging control circuit, a startup monitoring circuit, a capacitor voltage monitoring circuit, and a discharge diode. There are n capacitors, n current-limiting charging control circuits, and n discharge diodes, each corresponding to one another. There are n-1 capacitor voltage monitoring circuits. This invention also discloses a control method for this power supply circuit with temporary power supply and charge / discharge control functions. This invention satisfies the requirement of providing a stable voltage to the load when the DC power source fails, while avoiding the problem of large-capacity capacitors not being able to serve as temporary power sources in a timely manner due to prolonged charging. It also enables the function of completing load startup before starting charging, and the capacitor does not affect the inrush current or startup time during startup. By employing the control method of this invention, the reliable operation of the entire power supply system can be ensured.

Description

Technical Field

[0001] This invention relates to a power supply circuit, and more particularly to a power supply circuit and control method having temporary power supply and charge / discharge control functions. Background Technology

[0002] In some specialized fields, power supplies need to have temporary power supply capabilities to prevent safety accidents. For example, in the aerospace field, during flight, the power supply may be insufficient for a period of time (such as within a few hundred milliseconds) or even shut down due to the sudden start-up of certain equipment or other unexpected situations. Such instantaneous power shortages or shutdowns seriously threaten flight safety. To solve the problem of such instantaneous power outages, it is necessary to add a circuit to the power input terminal of the load to enable it to have a temporary power supply capability.

[0003] To address the aforementioned issues, capacitors are typically connected to the power output or the power input of the load (i.e., the electrical equipment). To ensure the capacitors can store sufficient energy to meet temporary power demands, sufficiently large capacitors are required, such as those with tens of thousands of microfarads or even larger capacities. With a sufficiently large capacitance, the energy released by such a large capacitor during a power outage can act as a temporary power source, effectively resolving power failures or insufficient power supply and ensuring flight safety.

[0004] However, aviation equipment also has requirements regarding the magnitude of the starting current (i.e., inrush current) and the starting time; that is, the equipment starting time cannot be too long, and the inrush current cannot be too large. When the capacitance on the power supply increases, it will inevitably lead to an increase in the starting current or a longer starting time, which may also affect flight safety.

[0005] The traditional methods to solve the above problems are: to solve the problem of power failure by increasing the capacitor capacity; and to solve the problems of starting current and starting time by reducing the capacitor capacity.

[0006] It is evident that the two solutions described above are contradictory. Some aircraft equipment systems require simultaneous solutions to starting current, starting time, and power failure issues, which obviously cannot be met using the traditional methods described above. Failure to address these issues would pose serious safety hazards and significantly hinder the development of the aviation industry. Therefore, a new solution capable of simultaneously providing temporary power supply and charge / discharge control functions is urgently needed to solve the current problems. Summary of the Invention

[0007] The purpose of this invention is to provide a power supply circuit and control method with temporary power supply and charge / discharge control functions in order to solve the above-mentioned problems.

[0008] The present invention achieves the above objectives through the following technical solutions:

[0009] A power supply circuit with temporary power supply and charge / discharge control functions is disposed between a DC power supply and a load. It includes a capacitor and a current-limiting charging control circuit. The positive and negative output terminals of the DC power supply are respectively connected to the positive and negative input terminals of the load. The power supply circuit further includes a start-up monitoring circuit for monitoring the start-up voltage of the DC power supply, a capacitor voltage monitoring circuit for monitoring the capacitor voltage, and a discharge diode for unidirectional discharge. There are n capacitors, current-limiting charging control circuits, and discharge diodes, each corresponding to one another, where n is an integer greater than 2. There are n-1 capacitor voltage monitoring circuits. The power input terminal of each current-limiting charging control circuit, the negative terminal of each discharge diode, and the positive input terminal of the start-up monitoring circuit are respectively connected to the positive output terminal of the DC power supply. The power output terminal of each current-limiting charging control circuit is respectively connected to the positive terminal of the corresponding capacitor and the positive terminal of the corresponding discharge diode. Then, the negative terminal of each capacitor, the negative input terminal of each capacitor voltage monitoring circuit, and the negative input terminal of the start-up monitoring circuit are respectively connected to the negative output terminal of the DC power supply. The positive terminal of the first capacitor is connected to the positive input terminal of the first capacitor voltage monitoring circuit, the positive terminal of the second capacitor is connected to the positive input terminal of the second capacitor voltage monitoring circuit, and so on, until the (n-1)th capacitor is connected to the positive input terminal of the (n-1)th capacitor voltage monitoring circuit. The signal output terminal of the start-up monitoring circuit is connected to the control input terminal of the first current-limiting charging control circuit, the control output terminal of the first capacitor voltage monitoring circuit is connected to the control input terminal of the second current-limiting charging control circuit, the control output terminal of the second capacitor voltage monitoring circuit is connected to the control input terminal of the third current-limiting charging control circuit, and so on, until the control output terminal of the (n-1)th capacitor voltage monitoring circuit is connected to the control input terminal of the nth current-limiting charging control circuit. The aforementioned current-limiting charging control circuit adopts a conventional charging circuit, such as the circuit disclosed in the invention patent with patent number "ZL202121698226.5" and patent name "A Current Overshoot Suppression Circuit Based on Negative Feedback Principle"; the aforementioned startup monitoring circuit and capacitor voltage monitoring circuit can adopt conventional monitoring circuits.

[0010] Preferably, to achieve better monitoring functionality and facilitate implementation, the startup monitoring circuit and the capacitor voltage monitoring circuit have the same circuit structure, which is as follows: including a first resistor, a second resistor, and an operational amplifier. The first end of the first resistor is connected to the first end of the second resistor and the negative input terminal of the operational amplifier. The positive input terminal of the operational amplifier is connected to a reference voltage. The second end of the first resistor serves as the positive input terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit. The second end of the second resistor serves as the negative input terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit. The output terminal of the operational amplifier serves as the signal output terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit.

[0011] Preferably, in order to prevent reverse current flow, the output terminal of the operational amplifier is connected to the positive terminal of an anti-reverse diode for preventing reverse current flow, and the negative terminal of the anti-reverse diode serves as the signal output terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit.

[0012] A control method for a power supply circuit with temporary power supply and charge / discharge control functions includes the following steps:

[0013] Step 1: Turn on the DC power supply. The load is powered on and starts. At this time, all the current-limiting charging control circuits are not working.

[0014] Step 2: After the DC power supply is turned on, the startup monitoring circuit detects the voltage value of the positive output terminal of the DC power supply in real time. When the voltage value reaches the preset startup charging threshold, the signal output by the startup monitoring circuit controls the first current limiting charging control circuit to work and start charging the first capacitor. The above-mentioned startup charging threshold corresponds to the voltage value of the positive output terminal of the DC power supply after the load is started.

[0015] Step 3: The first capacitor voltage monitoring circuit detects the positive voltage value of the first capacitor in real time. When the voltage value reaches the preset capacitor capacity threshold, the signal output by the first capacitor voltage monitoring circuit controls the second current limiting charging control circuit to start charging the second capacitor. The above-mentioned capacitor capacity threshold is the voltage value of the positive terminal of the corresponding capacitor when it is fully charged.

[0016] Step 4: Replace the previous capacitor voltage monitoring circuit with the next capacitor voltage monitoring circuit, and replace the previous current limiting charging control circuit with the next current limiting charging control circuit. Repeat step 3 until all the capacitors are fully charged.

[0017] Step 5: When the voltage at the positive output terminal of the DC power supply decreases or becomes zero, the positive voltage of all the capacitors is applied to the positive input terminal of the load through the corresponding discharge diode, automatically providing a stable input voltage to the load.

[0018] The beneficial effects of this invention are as follows:

[0019] This invention utilizes multiple small-capacity capacitors connected in parallel to form a large-capacity capacitor. A capacitor voltage monitoring circuit enables the sequential and rapid charging of these smaller capacitors. This satisfies the need for a stable voltage to the load during DC power outages while avoiding the problem of prolonged charging of the large-capacity capacitor, which could prevent it from functioning as a temporary power source. A startup monitoring circuit ensures that the load starts up before charging begins, regardless of the total capacity of the parallel capacitors, preventing any impact on the startup inrush current or startup time. A current-limiting charging control circuit prevents damage to the DC power supply or capacitors from excessive current. By employing this control method, optimal control is achieved, ensuring that the DC power supply, load, and capacitors are unaffected by temporary power outages or overcurrent surges during startup and operation, thus guaranteeing the reliable operation of the entire power system. Attached Figure Description

[0020] Figure 1 This is a circuit diagram of the power supply circuit with temporary power supply and charge / discharge control functions described in this invention.

[0021] Figure 2 This is a circuit diagram of the startup monitoring circuit and capacitor voltage monitoring circuit of the power supply circuit with temporary power supply and charge / discharge control functions described in this invention. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings:

[0023] like Figure 1As shown, the power supply circuit with temporary power supply and charge / discharge control functions described in this invention is located between the DC power supply and the load. It includes a capacitor, a current-limiting charging control circuit, a start-up monitoring circuit for monitoring the DC power supply's start-up voltage, a capacitor voltage monitoring circuit for monitoring the capacitor voltage, and a discharge diode for unidirectional discharge. The positive and negative output terminals of the DC power supply are respectively connected to the positive and negative input terminals of the load. There are n capacitors, current-limiting charging control circuits, and discharge diodes, each corresponding to one another. Specifically, the first capacitor C1, the first current-limiting charging control circuit, and the first discharge diode D1 correspond to each other; the second capacitor C2, the second current-limiting charging control circuit, and the second discharge diode D2 correspond to each other, and so on, with the nth capacitor Cn, the nth current-limiting charging control circuit, and the nth discharge diode Dn corresponding to each other. n is an integer greater than 2, preferably 5-15. There are n-1 capacitor voltage monitoring circuits. The power input terminal of each current-limiting charging control circuit, the negative terminal of each discharge diode, and the positive input terminal of the start-up monitoring circuit are respectively connected to the DC power supply. The positive output terminal of the DC power supply is connected. The power output terminal of each current-limiting charging control circuit is connected to the positive terminal of the corresponding capacitor and the positive terminal of the corresponding discharge diode. The negative terminal of each capacitor, the negative input terminal of each capacitor voltage monitoring circuit, and the negative input terminal of the start monitoring circuit are connected to the negative output terminal of the DC power supply. The positive terminal of the first capacitor C1 is connected to the positive input terminal of the first capacitor voltage monitoring circuit, the positive terminal of the second capacitor C2 is connected to the positive input terminal of the second capacitor voltage monitoring circuit, and so on, until the (n-1)th capacitor is connected to the positive input terminal of the (n-1)th capacitor voltage monitoring circuit. The signal output terminal of the start monitoring circuit is connected to the control input terminal of the first current-limiting charging control circuit. The control output terminal of the first capacitor voltage monitoring circuit is connected to the control input terminal of the second current-limiting charging control circuit. The control output terminal of the second capacitor voltage monitoring circuit is connected to the control input terminal of the third current-limiting charging control circuit, and so on, until the control output terminal of the (n-1)th capacitor voltage monitoring circuit is connected to the control input terminal of the nth current-limiting charging control circuit. The aforementioned current-limiting charging control circuit adopts the circuit disclosed in the invention patent with patent number "ZL 202121698226.5" and patent name "A Current Overshoot Suppression Circuit Based on Negative Feedback Principle".

[0024] like Figure 2As shown, preferably, in order to achieve better monitoring function and facilitate implementation, the circuit structure of the startup monitoring circuit and the capacitor voltage monitoring circuit are the same and their circuit structure is as follows: including a first resistor R1, a second resistor R2 and an operational amplifier IC1, the first end of the first resistor R1 is connected to the first end of the second resistor R2 and the negative input terminal of the operational amplifier IC1, the positive input terminal of the operational amplifier IC1 is connected to the reference voltage Vc, the second end of the first resistor R1 serves as the positive input terminal Vi+ of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit, the second end of the second resistor R2 serves as the negative input terminal Vi- of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit, and the output terminal of the operational amplifier IC1 is connected to the positive terminal of the anti-reverse diode D0 used to prevent reverse current flow, and the negative terminal of the anti-reverse diode D0 serves as the signal output terminal Vo of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit.

[0025] Combination Figure 1 and Figure 2 The control method used in the power supply circuit with temporary power supply and charge / discharge control functions described in this invention includes the following steps:

[0026] Step 1: Turn on the DC power supply and start the load. At this time, all current-limiting charging control circuits are not working, so not all capacitors are charged, thus realizing the function of starting first and then charging.

[0027] Step 2: After the DC power supply is turned on, the start monitoring circuit detects the voltage value of the positive output terminal of the DC power supply in real time. When the voltage value reaches the preset start charging threshold, the signal output by the start monitoring circuit controls the first current limiting charging control circuit to work and start charging the first capacitor C1. The above start charging threshold corresponds to the voltage value of the positive output terminal of the DC power supply after the load is started.

[0028] Step 3: The first capacitor voltage monitoring circuit detects the positive voltage value of the first capacitor C1 in real time. When the voltage value reaches the preset capacitor capacity threshold, the signal output by the first capacitor voltage monitoring circuit controls the second current limiting charging control circuit to start charging the second capacitor C2. The above-mentioned capacitor capacity threshold is the voltage value of the positive terminal of the corresponding capacitor when it is fully charged.

[0029] Step 4: Replace the previous capacitor voltage monitoring circuit with the next capacitor voltage monitoring circuit, and replace the previous current limiting charging control circuit with the next current limiting charging control circuit. Repeat step 3 until all capacitors are fully charged, that is, finally complete the charging of the nth capacitor Cn. In this way, the function of charging all capacitors in sequence is realized, and the charging time of each capacitor is short and the speed is fast.

[0030] Step 5: When the voltage at the positive output terminal of the DC power supply drops or becomes zero, the positive voltage of all capacitors is applied to the positive input terminal of the load through the corresponding discharge diodes, automatically providing a stable input voltage to the load. This achieves the function of each capacitor discharging through an independent line to provide temporary power to the load.

[0031] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the technical solutions of the present invention. Any technical solution that can be implemented based on the above embodiments without creative effort should be considered to fall within the scope of protection of the patent of the present invention.

Claims

1. A power supply circuit with temporary power supply and charge / discharge control functions, disposed between a DC power supply and a load, comprising a capacitor and a current-limiting charging control circuit, wherein the positive and negative output terminals of the DC power supply are respectively connected to the positive and negative input terminals of the load, characterized in that: The power supply circuit with temporary power supply and charge / discharge control functions further includes a startup monitoring circuit for monitoring the startup voltage of the DC power supply, a capacitor voltage monitoring circuit for monitoring the capacitor voltage, and a discharge diode for unidirectional discharge. There are n capacitors, n-1 current-limiting charging control circuits, and n-1 discharge diodes, each corresponding to the other. The power input terminal of each current-limiting charging control circuit, the negative terminal of each discharge diode, and the positive input terminal of the startup monitoring circuit are connected to the positive output terminal of the DC power supply. The power output terminal of each current-limiting charging control circuit is connected to the positive terminal of the corresponding capacitor and the positive terminal of the corresponding discharge diode. The negative terminal of each capacitor, the negative input terminal of each capacitor voltage monitoring circuit, and the negative input terminal of the startup monitoring circuit are all connected to the DC power supply. Each capacitor is connected to the negative output terminal of the DC power supply. The positive terminal of the first capacitor is connected to the positive input terminal of the first capacitor voltage monitoring circuit, the positive terminal of the second capacitor is connected to the positive input terminal of the second capacitor voltage monitoring circuit, and so on, until the (n-1)th capacitor is connected to the positive input terminal of the (n-1)th capacitor voltage monitoring circuit. The signal output terminal of the start monitoring circuit is connected to the control input terminal of the first current-limiting charging control circuit, the control output terminal of the first capacitor voltage monitoring circuit is connected to the control input terminal of the second current-limiting charging control circuit, the control output terminal of the second capacitor voltage monitoring circuit is connected to the control input terminal of the third current-limiting charging control circuit, and so on, until the control output terminal of the (n-1)th capacitor voltage monitoring circuit is connected to the control input terminal of the nth current-limiting charging control circuit.

2. The power supply circuit with temporary power supply and charge / discharge control functions according to claim 1, characterized in that: The startup monitoring circuit and the capacitor voltage monitoring circuit have the same circuit structure, which is as follows: including a first resistor, a second resistor, and an operational amplifier. The first end of the first resistor is connected to the first end of the second resistor and the negative input terminal of the operational amplifier. The positive input terminal of the operational amplifier is connected to a reference voltage. The second end of the first resistor serves as the positive input terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit. The second end of the second resistor serves as the negative input terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit. The output terminal of the operational amplifier serves as the signal output terminal of the corresponding startup monitoring circuit or the capacitor voltage monitoring circuit.

3. The power supply circuit with temporary power supply and charge / discharge control functions according to claim 2, characterized in that: The output terminal of the operational amplifier is connected to the positive terminal of an anti-reverse diode used to prevent reverse current flow, and the negative terminal of the anti-reverse diode serves as the signal output terminal of the corresponding startup monitoring circuit or capacitor voltage monitoring circuit.

4. A control method for a power supply circuit with temporary power supply and charge / discharge control functions as described in claim 1, 2, or 3, characterized in that: Includes the following steps: Step 1: Turn on the DC power supply. The load is powered on and starts. At this time, all the current-limiting charging control circuits are not working. Step 2: After the DC power supply is turned on, the startup monitoring circuit detects the voltage value of the positive output terminal of the DC power supply in real time. When the voltage value reaches the preset startup charging threshold, the signal output by the startup monitoring circuit controls the first current limiting charging control circuit to work and start charging the first capacitor. The above-mentioned startup charging threshold corresponds to the voltage value of the positive output terminal of the DC power supply after the load is started. Step 3: The first capacitor voltage monitoring circuit detects the positive voltage value of the first capacitor in real time. When the voltage value reaches the preset capacitor capacity threshold, the signal output by the first capacitor voltage monitoring circuit controls the second current limiting charging control circuit to start charging the second capacitor. The above-mentioned capacitor capacity threshold is the voltage value of the positive terminal of the corresponding capacitor when it is fully charged. Step 4: Replace the previous capacitor voltage monitoring circuit with the next capacitor voltage monitoring circuit, and replace the previous current limiting charging control circuit with the next current limiting charging control circuit. Repeat step 3 until all the capacitors are fully charged. Step 5: When the voltage at the positive output terminal of the DC power supply decreases or becomes zero, the positive voltage of all the capacitors is applied to the positive input terminal of the load through the corresponding discharge diode, automatically providing a stable input voltage to the load.

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