Universal backup power supply circuit and device for secondary circuit of power distribution equipment

Abstract

The invention discloses a universal backup power supply circuit and device for a secondary circuit of power distribution equipment, which adopts a modular design and realizes flexible conversion and stable output of alternating current and direct current through cooperation of a main control module and each module. The universal backup power supply can meet the power supply requirements of secondary circuits of various power distribution equipment in a production field, and the stability and efficiency of the power supply are improved; the system comprises an AC-DC power supply module, a DC-DC power supply module, a DC-AC power supply module, a main control module and a display unit module. The AC-DC power supply module comprises a filter protection circuit, a bridge rectifier circuit, a battery protection control circuit, a step-down circuit and a first feedback circuit, the filter protection circuit is connected in series with the bridge rectifier circuit, the bridge rectifier circuit is connected with the battery protection control circuit, the battery protection control circuit is connected with the step-down circuit, and the step-down circuit is connected with the first feedback circuit. The output end of the step-down circuit is connected with the first feedback circuit; the main control module comprises a single-chip microcomputer and a power supply control circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of backup power supplies, and in particular to a universal backup power supply circuit for a secondary circuit of a power distribution device. Background Art

[0002] The secondary circuit of the power distribution equipment is used to control, protect, adjust, measure and monitor the working conditions of various parameters and components in the primary circuit, and its power supply is of great importance. Damage to the backup power supply of the secondary circuit can easily cause the relay protection device to fail to operate correctly. In the case of failure of the protection device outlet of the State Grid Urumqi Power Supply Company, more than 80% of the failures are caused by the backup power supply problem. The failure of the protection device outlet will lead to the expansion of the scope of the fault power outage, greatly reducing the reliability of power supply.

[0003] At present, the secondary circuit power supply of the distribution equipment includes AC220V, DC220V, DC110V, DC48V, DC24V and other forms. The power supply voltage and AC / DC form are not the same. The traditional secondary circuit backup power supply has a single output mode and can only be adapted to the distribution equipment it is equipped with. The application mode is single, and the secondary voltage and AC / DC form of the on-site distribution equipment are different. The traditional secondary circuit backup power supply cannot adapt to the power supply needs of the secondary circuits of various distribution equipment in the production site. This leads to problems such as large purchases of various types of backup power supplies, high reserve costs, and low on-site survey efficiency during installation, which consumes a long time and causes large losses in manpower and material resources. With the popularization and application of power automation equipment, the power system has put forward higher requirements for uninterruptible power supply equipment.

[0004] To solve the above problems, we need to design a universal backup power supply for the secondary circuit of power distribution equipment, which has the characteristics of strong versatility and high professionalism, and can optimize system configuration, reduce system cost, and has a higher performance-price ratio than the conventional uninterruptible power supply. Summary of the invention

[0005] The technical problem to be solved by the present invention is to address the deficiencies in the above-mentioned prior art and disclose a universal backup power supply circuit and device for the secondary circuit of power distribution equipment. The circuit adopts a modular design and realizes flexible conversion and stable output of AC and DC power through the collaboration of the main control module and various modules. The universal backup power supply can meet the power supply requirements of the secondary circuits of various power distribution equipment in the production site and improve the stability and efficiency of the power supply.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a general backup power supply circuit for the secondary circuit of power distribution equipment, including an AC-DC power supply module, a DC-DC power supply module, a DC-AC power supply module, a main control module, and a display unit module;

[0007] The AC-DC power supply module includes a filter protection circuit, a bridge rectifier circuit, a battery protection control circuit, a buck circuit and a first feedback circuit, the filter protection circuit is connected in series with the bridge rectifier circuit, the bridge rectifier circuit is connected to the battery protection control circuit, the battery protection control circuit is connected to the buck circuit, and the output end of the buck circuit is connected to the first feedback circuit;

[0008] The DC-DC power supply module includes a first drive circuit, a boost rectifier circuit, and a second feedback circuit, wherein the first drive circuit is connected to the boost rectifier circuit, and the output end of the boost rectifier circuit is connected to the second feedback circuit;

[0009] The DC-AC power supply module includes a second drive circuit, a boost circuit, a rectifier circuit, an inverter circuit, and a third feedback circuit, wherein the second drive circuit is connected to the boost circuit, the boost circuit is connected to the rectifier circuit, the rectifier circuit is connected to the inverter circuit, and the output end of the inverter circuit is connected to the third feedback circuit;

[0010] The main control module includes a single-chip microcomputer and a power control circuit, and the output end of the single-chip microcomputer is respectively connected to the display unit module, the communication module, the debugging interface, the AC-DC power module, the DC-DC power module, the DC-AC power module, and the power control circuit;

[0011] The display unit module includes a digital tube display screen, an indicator light, a button, an LED panel indicator light, and a buzzer.

[0012] As a preferred embodiment of the present invention, the main control module includes a single-chip microcomputer, the output pins 35 to 42 of the single-chip microcomputer are connected to the digital tube display screen, the output pins 54 to 61 of the single-chip microcomputer are connected to the LED panel indicator light, the output pins 11 and 20 of the single-chip microcomputer are connected to the debugging interface, the power control circuit converts DC12V to DC5V, and the power control circuit supplies power to the main control module and the display unit module.

[0013] As a preferred embodiment of the present invention, the AC-DC power supply module enters the filtering protection circuit through the input AC220V for filtering protection, and then converts it into pulsating direct current through the bridge rectifier circuit. The pulsed direct current outputs DC24V through the step-down circuit, and then is monitored and fed back through the high-frequency 24V inductive type of the first feedback circuit.

[0014] As a preferred embodiment of the present invention, the DC24V is converted into AC24V by high-frequency switching.

[0015] As a preferred embodiment of the present invention, the DC-DC power supply module, through the input AC24V, the driving circuit drives the boost rectifier circuit to boost and rectify, and then monitors through the second feedback circuit. The boost circuit adopts a BOOST boost type, and the relationship between the output voltage and the input voltage is Vout=Vin*1 / 1-D, where Vout is the output voltage, Vin is the input voltage, and D is the duty cycle, taking a value of 0-1.

[0016] As a preferred embodiment of the present invention, the DC-AC power supply module receives AC24V as input, the driving circuit drives the boost circuit to boost the voltage, and then rectifies and converts it into AC220V through the inverter circuit, and then monitors and feedbacks through the third feedback circuit, and the inverter circuit controls the output voltage through pulse width modulation.

[0017] As a preferred embodiment of the present invention, the main control module is also provided with a protection circuit, which includes a relay, a diode, a transistor and an R46 resistor. The output signal is connected in series to one end of the R46 resistor, the other end of the R46 resistor is connected to the base of the transistor, the emitter of the transistor is grounded, the collector of the transistor is connected to a relay, and two diodes are connected in parallel to the relay. The protection circuit performs on-off control through the switching quantity of the output relay.

[0018] As a preferred embodiment of the present invention, the DC-DC power supply module can convert DC24V into DC48V, DC110V, and DC220V.

[0019] As a preferred implementation mode of the present invention, the single chip microcomputer is ATmega64L-8AC.

[0020] A universal backup power supply device for a secondary circuit of a power distribution device comprises a box, a lithium battery, a display screen, and heat dissipation holes. The box comprises a universal backup power supply circuit for a secondary circuit of the power distribution device.

[0021] As a preferred embodiment of the present invention, the lithium battery also includes a matching expansion pack, and the battery cell parameters of the lithium battery and the expansion pack are consistent.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The universal backup power supply circuit for the secondary circuit of a power distribution device of the present invention is a specially designed backup power supply applicable to universal equipment, and is intended to ensure that a stable and reliable power supply is provided for the secondary circuit of the power distribution device under various power conditions:

[0024] 1. AC-DC power module

[0025] This module is responsible for converting alternating current (AC) into direct current (DC), including filtering protection circuit: this circuit is used to filter out clutter and interference in the input AC power, while providing a certain degree of overvoltage and overcurrent protection to ensure the safe operation of subsequent circuits; bridge rectifier circuit: this circuit converts AC power into pulsating DC power. It uses a bridge structure composed of four diodes to achieve full-wave rectification of AC power; battery protection control circuit: this circuit is used to monitor the charging and discharging status of the battery to prevent the battery from overcharging or over-discharging, thereby extending the service life of the battery; buck circuit: the rectified DC power is stepped down to the required voltage level to meet the needs of subsequent circuits; first feedback circuit: this circuit is used to monitor the output voltage of the buck circuit and compare it with the set value. If the output voltage deviates from the set value, the feedback circuit will adjust the working state of the buck circuit to keep the output voltage stable;

[0026] 2. DC-DC power module

[0027] This module is responsible for converting the DC voltage into another DC voltage, including the first drive circuit: controlling the switch of the boost rectifier circuit to adjust the output voltage; the boost rectifier circuit: boosting the input DC voltage to the required voltage level and performing rectification; the second feedback circuit: similar to the first feedback circuit, used to monitor the output voltage of the boost rectifier circuit and adjust it as needed;

[0028] 3.DC-AC power module

[0029] This module is responsible for converting DC power into AC power, including the second drive circuit: controlling the switches of the boost circuit and the inverter circuit to achieve the conversion from DC to AC; boost circuit: boosting the input DC voltage to a voltage level suitable for the inverter circuit to work; rectifier circuit: in some cases, used to further rectify the boosted voltage; inverter circuit: converting DC power into AC power. This is achieved by controlling the on and off of the switching device; the third feedback circuit: monitoring the output voltage and frequency of the inverter circuit, and adjusting it as needed to ensure the stability of the output AC power;

[0030] 4. Main control module

[0031] This module is the core of the entire power supply circuit, responsible for monitoring and controlling the working status of each power supply module, including the single chip microcomputer: as the main controller, it is responsible for receiving and processing the feedback signals from each module, and issuing control instructions according to the preset algorithm; power supply control circuit: the power supply control circuit is responsible for converting the input DC12V voltage into DC5V voltage to meet the power supply requirements of the main control module and the display unit module;

[0032] 5. Display unit module

[0033] This module is used to display the working status and parameters of the power supply circuit, including the digital tube display screen: used to display digital information, such as voltage, current, etc.; indicator light: used to indicate the working status of the power supply circuit, such as normal, fault, etc.; button: used to manually set or adjust the parameters of the power supply circuit; LED panel indicator: provides intuitive visual indications, such as power on, charging status, etc.; buzzer: used to sound an alarm to remind the operator to pay attention to abnormal conditions of the power supply circuit;

[0034] In summary, this universal backup power supply circuit for the secondary circuit of power distribution equipment realizes flexible conversion and stable output of AC and DC through the coordinated work of various modules, providing reliable power supply guarantee for the secondary circuit of power distribution equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A control circuit diagram of a specific embodiment of the present invention;

[0036] Figure 2 is the AC-DC circuit diagram of the present invention;

[0037] Figure 3 is a DC-AC circuit diagram of the present invention;

[0038] Figure 4 is a DC-DC circuit diagram of the present invention;

[0039] Figure 5 It is the 110V circuit diagram of the present invention;

[0040] Figure 6 is a schematic diagram of a panel of the present invention;

[0041] Figure 7 It is a schematic diagram of the battery installation of the present invention;

[0042] Figure 8 It is a schematic diagram of the rear cover plate of the present invention;

[0043] Fig. 9 This is a physical diagram of the present invention. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. All other embodiments obtained by ordinary technicians in the field without making creative work based on the embodiments of the present invention shall fall within the scope of protection of the present invention.

[0045] The invention proposes a universal backup power supply for the secondary circuit of power distribution equipment, which has the characteristics of strong versatility and high professionalism, and can optimize system configuration, reduce system cost, and has a higher performance-price ratio than the conventional uninterruptible power supply. The theoretical basis of this project mainly involves rectification conversion technology, inverter technology, PWM wave control technology and DC conversion technology.

[0046] (1) Rectification and conversion technology: Rectification and conversion is a circuit that converts AC power into DC power. Most rectifier circuits are composed of transformers, rectifier main circuits, and filters. The function of the rectifier circuit is to convert the low-voltage AC power output by the AC step-down circuit into unidirectional pulsating DC power. This is the rectification process of AC power. The rectifier circuit is mainly composed of rectifier diodes.

[0047] (2) Inverter power supply and PWM wave control technology: Inverter circuit converts DC into AC. Inverter circuit can be used to form various AC power supplies and is widely used in industry. PWM pulse width modulation controls the output voltage by changing the pulse width and controls the output frequency by changing the cycle. The change of output frequency can be achieved by changing the modulation cycle of this pulse. The control method is to control the on and off of the switching device of the inverter circuit so that a series of pulses with equal amplitude are obtained at the output end, and these pulses are used to replace the sine wave or the required waveform.

[0048] (3) DC conversion technology: DC conversion circuit is a conversion circuit that converts a DC voltage with a fixed amplitude into a DC voltage with a variable amplitude and polarity. In production, it is used to form a DC pulse speed regulation power supply and a switching voltage regulator. Compared with the traditional linear DC voltage regulator, the switching voltage regulator has high efficiency and small size, and has become a new generation of DC voltage regulator.

[0049] The universal backup power supply for the secondary circuit of the power distribution equipment proposed in the present invention integrates the voltage, power and other data of the secondary circuit of the distribution network power distribution equipment, designs the rectifier circuit, voltage regulating circuit and inverter circuit that meet the requirements, and determines the total capacity of the battery according to the different backup times required by each system to ensure the effective power supply of the secondary circuit, thereby improving the distribution operation capacity and power supply reliability from the source.

[0050] The output voltage can be applied to the secondary circuits of power distribution equipment commonly found in distribution networks, and can be quickly retrofitted to equipment without backup power supplies on site.

[0051] The output voltage can be applied to the secondary circuit of the common power distribution equipment in the distribution network, so that the equipment with damaged on-site backup power supply can be quickly replaced.

[0052] The display unit module displays various power supply operating states, mainly including: output DC power, output AC voltage, module communication address, module temperature, fault status and other information.

[0053] The device can effectively serve as a backup power supply for the secondary circuit, effectively guarantee the power supply of the relay protection device, reduce the failure of the protection device outlet to operate due to insufficient power supply, reduce the expansion of fault power outages, and ensure the reliability of power supply to customers.

[0054] During the use of this device, the following beneficial effects will occur:

[0055] (1) The secondary circuit power supply form of the old ring main units, switch stations and switchgear handed over by customers is mostly PT direct power supply. After modification, a backup power supply consisting of a battery and a power management module is added between the PT and the secondary circuit, and the voltage output by the PT is connected to the input interface of the backup power supply, and the output of the backup power supply is connected to the secondary circuit that needs power supply. In the event of power outage or insufficient power supply, the modified universal backup power supply can continuously supply power to the secondary circuit and distribution automation terminal.

[0056] (2) The study found that the PT supply voltage in both direct PT power supply and PT power supply with backup power supply is AC220V; in the PT power supply with backup power supply, the output voltage of the backup power supply (i.e., the voltage required for the secondary circuit) has four types: AC220V, DC220V, DC48V, and DC24V. The backup power supply developed by the present invention sets its input voltage to AC220V and connects with the PT output; by adding rectification and inverter modules, it can output four voltages of AC220V, DC220V, DC48V, and DC24V, and simultaneously meets four types of secondary circuits with different voltage forms, ensuring its versatility.

[0057] (3) The existing backup power supplies have four types of output voltages: AC220V, DC220V, DC48V, and DC24V, which are respectively adapted to four types of secondary circuits with different voltage types. Therefore, the types of spare parts reserves are large and the reserve requirements are high, resulting in excessive consumption of manpower, material resources, and financial resources. The universal backup power supply developed by the present invention can reduce the reserve of spare parts, procurement costs, and management difficulty because it can simultaneously meet the needs of secondary circuits of different voltage types.

[0058] (4) The universal backup power supply developed by the present invention can output four types of voltage and current forms commonly used in the secondary circuit of the distribution equipment. When a problem occurs in the secondary circuit power supply of the distribution equipment, it can be directly replaced to quickly solve the secondary circuit power supply problem of the distribution equipment, thereby improving the accuracy of protection action, reducing the scope of fault power outages, and ensuring the reliability of power supply to users.

[0059] like Figures 1 to 9 As shown, it shows a specific embodiment of the present invention; Figures 1 to 9As shown, the present invention discloses a universal backup power supply circuit for the secondary circuit of a power distribution device, including an AC-DC power supply module, a DC-DC power supply module, a DC-AC power supply module, a main control module, and a display unit module;

[0060] The AC-DC power supply module includes a filter protection circuit, a bridge rectifier circuit, a battery protection control circuit, a buck circuit and a first feedback circuit, the filter protection circuit is connected in series with the bridge rectifier circuit, the bridge rectifier circuit is connected to the battery protection control circuit, the battery protection control circuit is connected to the buck circuit, and the output end of the buck circuit is connected to the first feedback circuit;

[0061] The DC-DC power supply module includes a first drive circuit, a boost rectifier circuit, and a second feedback circuit, wherein the first drive circuit is connected to the boost rectifier circuit, and the output end of the boost rectifier circuit is connected to the second feedback circuit;

[0062] The DC-AC power supply module includes a second drive circuit, a boost circuit, a rectifier circuit, an inverter circuit, and a third feedback circuit, wherein the second drive circuit is connected to the boost circuit, the boost circuit is connected to the rectifier circuit, the rectifier circuit is connected to the inverter circuit, and the output end of the inverter circuit is connected to the third feedback circuit;

[0063] The main control module includes a single-chip microcomputer and a power control circuit, and the output end of the single-chip microcomputer is respectively connected to the display unit module, the communication module, the debugging interface, the AC-DC power module, the DC-DC power module, the DC-AC power module, and the power control circuit;

[0064] The display unit module includes a digital tube display screen, an indicator light, a button, an LED panel indicator light, and a buzzer.

[0065] Preferably, Figure 1 As shown, the main control module includes a single-chip microcomputer, the output pins 35 to 42 of the single-chip microcomputer are connected to the digital tube display screen, the output pins 54 to 61 of the single-chip microcomputer are connected to the LED panel indicator light, the output pins 11 and 20 of the single-chip microcomputer are connected to the debugging interface, and the power control circuit converts DC12V into DC5V, and the power control circuit supplies power to the main control module and the display unit module.

[0066] The circuit of the present invention needs to meet the output of a wide voltage range from 24V to 220V, and also have both AC and DC forms to meet universal requirements.

[0067] As the main controller, the single-chip microcomputer plays a core role in the general backup power supply circuit of the secondary circuit of the power distribution equipment. Its output pins are connected to multiple key components to achieve comprehensive monitoring and display of the power supply circuit;

[0068] 1. Connection between the microcontroller output pin and the digital tube display

[0069] Pin range: The output pins 35 to 42 of the microcontroller are responsible for sending data signals to the digital tube display to display the working status, voltage value, current value and other key parameters of the power supply circuit; the microcontroller can convert the data to be displayed into a format that the digital tube display can recognize and send it out through these pins.

[0070] 2. Connection between the MCU output pin and the LED panel indicator

[0071] Pin range: The output pins 54 to 61 of the microcontroller are used to control the on and off of the LED panel indicator lights to provide intuitive visual indications, such as power on, charging status, fault alarm, etc. The microcontroller sends control signals to the LED panel indicator lights through these pins according to the working status of the power circuit and the preset logical conditions to switch the indicator lights on and off.

[0072] 3. Connection between MCU output pin and debug interface

[0073] Pin range: The output pins 11 and 20 of the MCU are used to connect to the debugging interface, such as the JTAG interface or the SWD interface, so as to program, debug and troubleshoot the MCU during development or maintenance. Through dedicated debugging tools and appropriate connecting lines, you can connect to these pins to achieve communication and data exchange with the MCU.

[0074] 4. Function and power supply of power control circuit

[0075] The power control circuit is responsible for converting the input DC12V voltage into DC5V voltage to meet the power supply requirements of the main control module and the display unit module. The converted DC5V voltage is connected through appropriate circuits to provide stable power for the main control module (including the single-chip microcomputer) and the display unit module (including the digital tube display and the LED panel indicator).

[0076] In summary, the single-chip microcomputer is connected to the digital tube display screen, LED panel indicator light and debugging interface through its output pins, realizing comprehensive monitoring and display of the power circuit. At the same time, the power control circuit converts the input DC12V voltage into DC5V voltage to provide a stable power supply for the main control module and the display unit module. These designs ensure the stability and reliability of the universal backup power supply circuit of the secondary circuit of the power distribution equipment.

[0077] Preferably, Figure 2As shown, the AC-DC power supply module enters the filter protection circuit through the input AC220V for filtering protection, and then converts it into pulsating direct current through the bridge rectifier circuit. The pulsed direct current outputs DC24V through the step-down circuit, and then is monitored and fed back through the high-frequency 24V inductive type of the first feedback circuit.

[0078] The AC-DC power module is an important component of the general backup power circuit of the secondary circuit of the power distribution equipment. It is responsible for converting the input alternating current (AC220V) into stable direct current (DC220V is processed and output as DC24V).

[0079] 1. Input and filter protection

[0080] Input: The AC-DC power module first receives alternating current (AC220V) from the power grid. This is the input power of the power module.

[0081] Filter protection: The input AC power first passes through the filter protection circuit. The main function of the filter protection circuit is to remove the clutter and interference in the AC power, while providing certain overvoltage and overcurrent protection. This helps to ensure the stable operation of the subsequent circuit and prevent circuit damage caused by power fluctuations or abnormalities.

[0082] 2. Bridge Rectification

[0083] Bridge rectifier circuit: After filtering and protection, the AC power enters the bridge rectifier circuit. The bridge rectifier circuit consists of four diodes, which are connected in a specific way to achieve full-wave rectification of the AC power. This means that each half cycle of the AC power is converted into a part of the DC power, thus obtaining pulsating DC power.

[0084] Pulsating DC: The output of the bridge rectifier circuit is pulsating DC. This DC contains a certain amount of ripple, that is, voltage fluctuations. This is because the bridge rectifier circuit only converts AC into DC without smoothing it.

[0085] 3. Buck circuit

[0086] Step-down circuit: The pulsating DC power then enters the step-down circuit. The main function of the step-down circuit is to reduce the voltage of the pulsating DC power to the required DC voltage level (DC24V in this case). This is usually achieved through a combination of components such as transformers, inductors, capacitors and switching devices.

[0087] DC24V output: After being processed by the step-down circuit, the voltage of the pulsating DC power is stably reduced to DC24V and output to the subsequent circuit.

[0088] 4. Feedback monitoring

[0089] First feedback circuit: The output end of the buck circuit is connected to the first feedback circuit. The main function of the first feedback circuit is to monitor and feedback the output voltage. This is usually achieved through a high-frequency induction circuit, which can detect the change of the output voltage in real time and compare it with the preset voltage value.

[0090] Monitoring feedback: If the output voltage deviates from the preset value, the first feedback circuit sends a feedback signal to the main control module. The main control module adjusts the working state of the buck circuit according to this signal to ensure the stability and accuracy of the output voltage. This feedback mechanism helps ensure that the AC-DC power supply module can provide a stable output voltage under various load and power fluctuation conditions.

[0091] In summary, the AC-DC power module converts the input AC power (AC220V) into stable DC power (DC24V) through filtering protection, bridge rectification, step-down circuit and feedback monitoring, and provides reliable power for subsequent circuits. This design ensures the stability and reliability of the general backup power supply circuit of the secondary circuit of the power distribution equipment.

[0092] Preferably, Figure 2 As shown, the DC24V is converted into AC24V through high-frequency switching.

[0093] The process of converting DC24V (direct current 24 volts) into AC24V (alternating current 24 volts) through high-frequency switching usually involves inverter technology.

[0094] Inversion is the process of converting direct current into alternating current. In applications where DC24V is converted to AC24V, an inverter circuit is required to achieve this conversion. The inverter circuit is usually composed of switching devices (such as MOSFET, IGBT, etc.), control circuits, and filter circuits.

[0095] High-frequency switching is a key step in the inverter circuit. The switch device is driven by the control circuit to perform switching operations at a high frequency. This high-frequency switching operation causes the DC power to produce a changing current and voltage waveform in the inverter circuit, thereby converting it into AC power.

[0096] Preferably, Figure 4 As shown, the DC-DC power supply module drives the boost rectifier circuit to boost and rectify through the input AC24V, and then monitors through the second feedback circuit. The boost circuit adopts BOOST boost type, and the relationship between the output voltage and the input voltage is Vout=Vin*1 / 1-D, where Vout is the output voltage, Vin is the input voltage, and D is the duty cycle, which takes a value of 0-1.

[0097] A DC-DC power module is a power supply device that converts a DC voltage into another DC voltage. Its working principle is as follows:

[0098] 1. Input and rectification:

[0099] The AC24V input power first passes through the rectifier circuit to convert the AC power into DC power. The rectifier circuit is usually composed of a diode or a rectifier bridge, which can ensure the unidirectional flow of current.

[0100] 2. Boost rectification:

[0101] The rectified DC power enters the boost rectifier circuit. This circuit adopts BOOST boost design, which increases the input voltage to the required output voltage level by controlling the on and off time of the switching device.

[0102] The core of the BOOST boost circuit is a switching device (such as MOSFET or IGBT), an inductor, and a capacitor. When the switching device is turned on, the input voltage is applied to the inductor, and the inductor begins to store electrical energy. When the switching device is turned off, the inductor releases the stored electrical energy, charging the capacitor through components such as diodes, thereby increasing the output voltage.

[0103] 3. Second feedback circuit monitoring:

[0104] The output end of the boost rectifier circuit is connected to the second feedback circuit. The main function of this circuit is to monitor the output voltage in real time and feed back the monitoring result to the control circuit.

[0105] Among them, the relationship between the output voltage and the duty cycle: the relationship between the output voltage Vout and the input voltage Vin is Vout = Vin / (1-D), where D is the duty cycle, that is, the ratio of the switch device conduction time to the total cycle time. This formula describes the basic working principle of the BOOST boost circuit and the output voltage adjustment method.

[0106] The output voltage Vout can be controlled by adjusting the duty cycle D. The larger the duty cycle, the higher the output voltage; the smaller the duty cycle, the lower the output voltage.

[0107] If the output voltage deviates from the preset value, the control circuit will adjust the on and off time of the switching device (ie, the duty cycle D) according to the feedback signal to ensure the stability and accuracy of the output voltage.

[0108] The use of high-frequency switching devices and advanced control technology makes the DC-DC power supply module have a high conversion efficiency. Through the synergy of feedback circuit and control circuit, the stability and accuracy of output voltage can be ensured. By adjusting the duty cycle and circuit parameters, a wide range of output voltage can be adjusted.

[0109] In summary, the DC-DC power supply module realizes stable regulation and efficient conversion of output voltage through the synergy of the boost rectifier circuit and the feedback circuit through the input AC24V (first rectified to DC). The module has the characteristics of high efficiency, stability, flexibility and miniaturization, and is widely used in various electronic devices.

[0110] Preferably, Figure 3 As shown, the DC-AC power supply module receives AC24V as input, and the driving circuit drives the boost circuit to boost the voltage, which is then rectified and converted into AC220V through the inverter circuit, and then monitored and fed back through the third feedback circuit. The inverter circuit controls the output voltage through pulse width modulation.

[0111] The DC-AC power module is a power supply device that converts DC voltage into AC voltage. Its working principle is as follows:

[0112] 1. Input boost circuit:

[0113] The AC24V input power first passes through the boost circuit. The core of the boost circuit is components such as switching devices (such as MOSFET or IGBT), inductors and capacitors. By controlling the on and off time of the switching device, the input voltage can be increased to the required DC voltage level.

[0114] The working principle of the boost circuit is similar to that of the BOOST boost circuit. The voltage is increased through the energy storage and release of the inductor and the smooth filtering of the capacitor.

[0115] 3. Rectification:

[0116] Rectifier circuit, converts AC to DC. Rectifier circuit usually consists of diodes or rectifier bridge to ensure unidirectional flow of current.

[0117] 4. Inverter circuit:

[0118] The boosted DC power enters the inverter circuit and is converted into AC power through the alternating on and off of a series of switching devices (such as transistors).

[0119] The core of the inverter circuit is pulse width modulation (PWM) technology, which can generate AC waveforms of different frequencies and amplitudes by precisely controlling the on-time of each switching device.

[0120] 5. Third feedback circuit monitoring:

[0121] The output end of the inverter circuit is connected to the third feedback circuit. The main function of this circuit is to monitor the output voltage in real time and feed back the monitoring result to the control circuit.

[0122] If the output voltage deviates from the preset value (such as AC220V), the control circuit will adjust the on and off time of the switching device (ie, the pulse width modulation parameters) according to the feedback signal to ensure the stability and accuracy of the output voltage.

[0123] This module uses high-frequency switching devices and advanced control technology to make the DC-AC power module have a high conversion efficiency. Through the synergy of the feedback circuit and the control circuit, the stability and accuracy of the output voltage can be ensured. By adjusting the pulse width modulation parameters and circuit parameters, the frequency, amplitude and other characteristics of the output voltage can be adjusted.

[0124] Preferably, Figure 1 As shown, the main control module is also provided with a protection circuit, which includes a relay, a diode, a transistor and an R46 resistor. The output signal is connected in series to one end of the R46 resistor, the other end of the R46 resistor is connected to the base of the transistor, the emitter of the transistor is grounded, the collector of the transistor is connected to a relay, and two diodes are connected in parallel to the relay. The protection circuit is controlled on and off by the switching value of the output relay.

[0125] The protection circuit is an important part of the main control module, which is designed to ensure that the circuit can work safely and reliably under abnormal conditions. The protection circuit includes components such as relays, diodes, transistors and R46 resistors, and the on-off control is performed through the switching value of the output relay to protect the equipment and components in the circuit from damage.

[0126] The output signal is connected in series with one end of the R46 resistor. The R46 resistor plays the role of current limiting and voltage dividing, protecting the subsequent circuit from the impact of excessive current. The other end of the R46 resistor is connected to the base of the transistor. The transistor acts as a current control element and controls the collector current according to the change of the base current. The emitter of the transistor is grounded to provide a stable reference potential for the circuit. The collector of the transistor is connected to the relay. The relay acts as a switching element and controls the on and off of the circuit according to the output of the transistor. Two diodes are connected in parallel to the relay. These two diodes are usually used as protection diodes to prevent the reverse electromotive force generated by the relay when it is disconnected from damaging the transistor or other circuit components.

[0127] Working principle:

[0128] When the output signal is normal, the R46 resistor transmits the signal to the base of the transistor. The transistor controls the collector current according to the size of the base current, thereby controlling the on and off state of the relay.

[0129] When an abnormal situation occurs in the circuit (such as overload, short circuit, etc.), the protection circuit will detect these abnormal signals and control the disconnection of the relay through the transistor, thereby cutting off the circuit and protecting the equipment and components from damage. The two diodes connected in parallel to the relay play a protective role when the relay is disconnected. They can absorb the reverse electromotive force generated by the relay and prevent this reverse voltage from damaging other circuit components.

[0130] On / off control:

[0131] The protection circuit is controlled by the switch quantity of the output relay. When the relay is closed, the circuit is in the on state; when the relay is open, the circuit is cut off. This on-off control can achieve fast and reliable protection of the circuit, ensuring that the circuit can be cut off in time under abnormal circumstances to prevent damage to equipment and components.

[0132] In summary, the protection circuit in the main control module, through the synergistic effect of components such as relays, diodes, transistors and R46 resistors, includes protection measures such as overvoltage, undervoltage, overload, and short circuit, ensuring the safe operation of the power module and load equipment, and realizing fast and reliable protection of the circuit. The protection circuit has the characteristics of fast response, high reliability, comprehensive protection and easy maintenance.

[0133] Preferably, Figures 4-5 As shown, the DC-DC power supply module can convert DC24V into DC48V, DC110V, and DC220V.

[0134] The traditional secondary circuit backup power supply cannot adapt to the power supply requirements of the secondary circuits of various power distribution equipment in the production site. The secondary circuit power supply of the power distribution equipment includes AC220V, DC220V, DC110V, DC48V, DC24V and other forms. The power supply voltage and AC / DC form are not the same. In order to meet the universal requirements, the present invention develops an output voltage and form that meets the universal requirements.

[0135] Preferably, Figure 1 As shown, the single chip microcomputer is ATmega64L-8AC.

[0136] ATmega64L-8AC is a high-performance, low-power 8-bit microcontroller based on the AVR architecture. This microcontroller uses a 64-pin TQFP package and provides 53 programmable I / O ports, which is convenient for connecting and expanding external devices. Therefore, the comprehensive selection effect is the best.

[0137] A universal backup power supply device for a secondary circuit of a power distribution device comprises a box, a lithium battery, a display screen, and heat dissipation holes. The box comprises a universal backup power supply circuit for a secondary circuit of the power distribution device.

[0138] The backup power supply device developed by this circuit is as follows Figures 1 to 8 As shown in the figure, the universal backup power supply device for the secondary circuit of power distribution equipment is a backup power supply solution designed specifically for the secondary circuit of power distribution equipment. It integrates the box, display screen, heat dissipation holes and internal backup power supply circuit to provide stable and reliable power support for the secondary circuit of power distribution equipment.

[0139] The new highlights of the universal backup power supply technology for secondary equipment mainly include the following aspects:

[0140] 1. Intelligence and digitization: configurable 4G / 5G communication module and real-time signal monitoring.

[0141] 2. Efficient conversion: Multifunctional AC-DC, DC-DC, and DC-AC have excellent conversion capabilities, can achieve seamless switching between DC input and output, and have extremely high conversion efficiency, providing flexible and diverse solutions for various energy application scenarios.

[0142] 3. Wide voltage range adaptability: The power supply product has a wide voltage input range.

[0143] 4. Accurate current and voltage control: The power supply product can accurately output the required current and voltage values ​​according to the user's settings, and maintain a high degree of stability during operation. This precise control capability is crucial for some devices and applications that require extremely high power quality.

[0144] 5. Efficient heat dissipation design: In order to cope with high-load operation, the power supply product adopts an efficient heat dissipation design, with a silent fan, to ensure that the performance will not be degraded due to overheating during long-term use. This design not only increases the service life of the power supply, but also reduces noise pollution.

[0145] 6. Multiple protection mechanisms: The power supply has built-in multiple protection mechanisms, such as over-current, over-voltage and short-circuit protection, to provide users with comprehensive safety protection. These mechanisms can effectively prevent the power supply from being damaged under abnormal circumstances and protect the safety of equipment and users.

[0146] 7. Modular design: The power supply product adopts modular design to improve the aesthetics. This design not only facilitates the user, but also improves the compatibility and flexibility of the power supply.

[0147] Preferably, the lithium battery also includes a matching expansion pack, and the battery cell parameters of the lithium battery and the expansion pack are consistent.

[0148] The lithium battery capacity expansion pack is a flexible and effective battery capacity expansion solution. By ensuring the consistency of lithium battery and expansion pack cell parameters, users can easily increase the battery life of the device and flexibly adjust the battery capacity according to actual needs, thereby increasing the power supply by expanding the battery capacity.

[0149] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the field without departing from the purpose of the present invention. These changes involve related technologies well known to those skilled in the art, which all fall within the scope of protection of the patent of the present invention.

[0150] Many other changes and modifications may be made without departing from the concept and scope of the present invention.It should be understood that the present invention is not limited to the specific embodiments, and the scope of the present invention is defined by the appended claims.

Claims

1. A universal backup power supply circuit for the secondary circuit of a power distribution equipment, characterized in that: Including AC-DC power supply module, DC-DC power supply module, DC-AC power supply module, main control module, display unit module; The AC-DC power supply module includes a filter protection circuit, a bridge rectifier circuit, a battery protection control circuit, a buck circuit and a first feedback circuit, the filter protection circuit is connected in series with the bridge rectifier circuit, the bridge rectifier circuit is connected to the battery protection control circuit, the battery protection control circuit is connected to the buck circuit, and the output end of the buck circuit is connected to the first feedback circuit; The DC-DC power supply module includes a first drive circuit, a boost rectifier circuit, and a second feedback circuit, wherein the first drive circuit is connected to the boost rectifier circuit, and the output end of the boost rectifier circuit is connected to the second feedback circuit; The DC-AC power supply module includes a second drive circuit, a boost circuit, a rectifier circuit, an inverter circuit, and a third feedback circuit, wherein the second drive circuit is connected to the boost circuit, the boost circuit is connected to the rectifier circuit, the rectifier circuit is connected to the inverter circuit, and the output end of the inverter circuit is connected to the third feedback circuit; The main control module includes a single-chip microcomputer and a power control circuit, and the output end of the single-chip microcomputer is respectively connected to the display unit module, the communication module, the debugging interface, the AC-DC power module, the DC-DC power module, the DC-AC power module, and the power control circuit; The display unit module includes a digital tube display screen, an indicator light, a button, an LED panel indicator light, and a buzzer.

2. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 1, characterized in that: The main control module includes a single-chip microcomputer, the output pins 35 to 42 of the single-chip microcomputer are connected to the digital tube display screen, the output pins 54 to 61 of the single-chip microcomputer are connected to the LED panel indicator light, the output pins 11 and 20 of the single-chip microcomputer are connected to the debugging interface, and the power control circuit converts DC12V into DC5V, and the power control circuit supplies power to the main control module and the display unit module.

3. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 2, characterized in that: The AC-DC power supply module enters the filter protection circuit through the input AC220V for filtering protection, and then converts it into pulsating direct current through the bridge rectifier circuit. The pulsed direct current outputs DC24V through the step-down circuit, and then is monitored and fed back through the high-frequency 24V induction type of the first feedback circuit.

4. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 3, characterized in that: The DC24V is converted into AC24V through high-frequency switching.

5. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 4, characterized in that: The DC-DC power supply module drives the boost rectifier circuit to boost and rectify through the input AC24V, and then monitors through the second feedback circuit. The boost circuit adopts the BOOST boost type, and the relationship between the output voltage and the input voltage is Vout=Vin*1 / 1-D, where Vout is the output voltage, Vin is the input voltage, and D is the duty cycle, which takes a value of 0-1.

6. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 5, characterized in that: The DC-AC power supply module receives AC24V as input, and the driving circuit drives the boost circuit to boost the voltage, which is then rectified and converted into AC220V through the inverter circuit. The third feedback circuit performs monitoring and feedback, and the inverter circuit controls the output voltage through pulse width modulation.

7. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in any one of claims 1 to 6, characterized in that: The main control module is also provided with a protection circuit, which includes a relay, a diode, a transistor and an R46 resistor. The output signal is connected in series to one end of the R46 resistor, the other end of the R46 resistor is connected to the base of the transistor, the emitter of the transistor is grounded, the collector of the transistor is connected to the relay, and two diodes are connected in parallel to the relay. The protection circuit performs on-off control through the switching value of the output relay.

8. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 5, characterized in that: The DC-DC power supply module can convert DC24V into DC48V, DC110V, and DC220V.

9. A general backup power supply circuit for a secondary circuit of a power distribution equipment as claimed in claim 8, characterized in that: The single chip microcomputer is ATmega64L-8AC.

10. A universal backup power supply device for the secondary circuit of power distribution equipment, comprising a box, a lithium battery, a display screen, and a heat dissipation hole, characterized in that: The box includes a universal backup power supply circuit for the secondary circuit of a power distribution equipment as described in any one of claims 1 to 9.

11. A general-purpose backup power supply device for a secondary circuit of a power distribution device as claimed in claim 10, characterized in that: The lithium battery also includes a matching expansion pack, and the battery cell parameters of the lithium battery and the expansion pack are consistent.

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