An intelligent management circuit for ac-dc hybrid microgrid power

Abstract

This invention discloses an intelligent power management circuit for a hybrid AC / DC microgrid, relating to the field of hybrid microgrid technology. It includes a microcontroller module that controls a high-voltage conversion module and a low-voltage conversion module to supply power to a backup power module. When an imbalance occurs on the AC or DC bus, AC / DC power exchange is performed. When both are insufficient in power, a boost mode is activated to maintain power exchange in conjunction with the backup power module. When the backup power module is at low voltage, the output voltage of the low-voltage conversion module is increased. When the distribution network is without power, the high-voltage conversion module is controlled to distribute power to the AC or DC network according to distribution priority. If the backup power module is also without power, AC power supplied by the distribution network will be transmitted to maintain power exchange. This intelligent power management circuit for a hybrid AC / DC microgrid can maintain power balance on the AC and DC buses and automatically adjust the voltage gain according to the power state during power exchange to meet the power demand of the AC and DC buses under different power conditions.

Description

Technical Field

[0001] This invention relates to the field of hybrid microgrid technology, specifically to an AC / DC hybrid microgrid power intelligent management circuit. Background Technology

[0002] Depending on the bus voltage, microgrids can be divided into AC microgrids, DC microgrids, and AC / DC hybrid microgrids. Among them, AC / DC hybrid microgrids are convenient for simultaneously accepting AC and DC power sources and loads, and can improve power supply reliability and continuity through mutual support between AC and DC buses. In the existing technology, bidirectional inverters are used to perform inversion or rectification to achieve DC-AC or AC-DC conversion in order to realize AC-DC mutual power supply. However, when both the DC bus and the AC bus experience insufficient power, the DC bus and the AC bus will not be able to continue to maintain the power supply interaction state, and the voltage gain state cannot be automatically adjusted according to the power state during power interaction. Therefore, improvements are needed. Summary of the Invention

[0003] This invention provides an AC / DC hybrid microgrid power intelligent management circuit to solve the problems mentioned in the background art.

[0004] According to an embodiment of the present invention, an AC / DC hybrid microgrid power intelligent management circuit is provided, comprising: an AC power module, a low-voltage conversion module, a DC power module, a high-voltage conversion module, a backup power module, and a microcontroller module;

[0005] The AC power module is connected to the DC power module and is used to access AC power provided by the AC bus, access AC power provided by the distribution network and control the transmission of power. It rectifies and filters the AC power and outputs the first power. It inverts and filters the third power or DC power transmitted by the DC power module and transmits it to the AC bus or distribution network.

[0006] The low-voltage conversion module, connected to the backup power module and the high-voltage conversion module, is used to select the degree of series coupling. When the boost mode is started, it performs series coupling and isolation transformation on the backup power provided by the backup power module and outputs the second power. When the buck mode is started, it isolates, steps down, and rectifies the fourth power output by the high-voltage conversion module and outputs charging power.

[0007] The high-voltage conversion module is connected to the AC power module and the DC power module. When the boost mode is started, it controls multiple capacitors to alternately store and discharge the second electrical energy, performs voltage clamping, equalization boost and rectification, and outputs the third electrical energy. When the buck mode is started, it performs buck, phase shift control and inversion processing on the DC power provided by the DC power module and outputs the fourth electrical energy.

[0008] The DC power module is used to transmit the third or first electrical energy to the DC bus, receive the DC power provided by the DC bus and control the transmission status of the DC power, and transmit the third or DC power to the AC power module.

[0009] The backup power module is used to store charging energy, release the stored energy, and provide backup power.

[0010] The microcontroller module connects to the AC power module, low-voltage conversion module, DC power module, high-voltage conversion module, and backup power module. It controls the high-voltage and low-voltage conversion modules to initiate buck mode and controls the backup power module to store energy. When there is an imbalance on the AC or DC bus, it controls the power transmission and inverter status of the AC power module to complete the power exchange between the AC and DC power modules. When both the AC and DC buses are underpowered, it controls the backup power module to discharge, controls the low-voltage and high-voltage conversion modules to initiate boost mode, and maintains power exchange. If the backup power is at low voltage, it increases the voltage output of the low-voltage conversion module and controls the AC power module to transmit AC power from the distribution network. When the distribution network is de-energized, it controls the high-voltage conversion module to distribute power to the AC or DC power module according to the distribution priority of the AC and DC buses. If the backup power module is de-energized, it controls the AC power module to transmit AC power from the distribution network and maintain power exchange.

[0011] As a further embodiment of the present invention: the AC power module includes an AC bus interface, a first circuit breaker, a distribution network interface, a first bidirectional converter, a first capacitor, and a second circuit breaker; the DC power module includes a DC bus interface.

[0012] Preferably, the first end of the AC bus interface is connected to the first end of the first circuit breaker and the first AC end of the first bidirectional converter; the second end of the AC bus interface is connected to the second end of the first circuit breaker and the second AC end of the first bidirectional converter; the third end of the AC bus interface is connected to the third end of the first circuit breaker and the third AC end of the first bidirectional converter; the fourth, fifth, and sixth ends of the first circuit breaker are respectively connected to the first, second, and third ends of the distribution network interface; the first DC end of the first bidirectional converter is connected to the first end of the second circuit breaker and is connected to the second DC end of the first bidirectional converter and the second end of the second circuit breaker through the first capacitor; and the third and fourth ends of the second circuit breaker are respectively connected to the first and second ends of the DC bus interface.

[0013] As a further embodiment of the present invention: the low-voltage conversion module includes a first coupling inductor, a second power transistor, a fourth capacitor, a fourth power transistor, a third capacitor, a first power transistor, a third power transistor, a second capacitor, and a second coupling inductor; the microcontroller module includes a first controller;

[0014] Preferably, the first end of the primary side of the first coupling inductor is connected to the first end of the primary side of the second coupling inductor and one end of the second capacitor. The second end of the primary side of the first coupling inductor is connected to the source of the second power transistor. The drain of the second power transistor is connected to the second end of the secondary side of the first coupling inductor and is connected to the source of the fourth power transistor, the drain of the third power transistor, and the second end of the primary side of the second coupling inductor through the fourth capacitor. The first end of the secondary side of the first coupling inductor is connected to the first end of the secondary side of the second coupling inductor. The drain of the fourth power transistor is connected to the source of the third power transistor, the source of the first power transistor, the other end of the second capacitor, and the second DC terminal of the first bidirectional converter through the third capacitor. The gates of the first power transistor, the second power transistor, the third power transistor, and the fourth power transistor are respectively connected to the IO1, IO2, IO3, and IO4 terminals of the first controller.

[0015] As a further embodiment of the present invention: the low-voltage conversion module further includes a first thyristor, a second thyristor, and a first inverter;

[0016] Preferably, the first end of the first thyristor is connected to the drain of the second power transistor, the second end of the first thyristor and one end of the second thyristor are connected to the source of the third power transistor, the control end of the first thyristor is connected to the output end of the first inverter, and the input end of the first inverter is connected to the control end of the second thyristor and the IO11 end of the first controller.

[0017] As a further embodiment of the present invention: the DC power supply module further includes a third thyristor, a fourth thyristor, a fifth thyristor, and a sixth thyristor;

[0018] Preferably, the first end of the third thyristor is connected to the first DC terminal of the first bidirectional converter, the second end of the third thyristor is connected to one end of the fourth thyristor, the other end of the fourth thyristor is connected to the first terminal of the DC bus interface, one end of the fifth thyristor is connected to the second terminal of the DC bus interface, the other end of the fifth thyristor is connected to the first end of the sixth thyristor, the second end of the sixth thyristor is connected to the second DC terminal of the first bidirectional converter, the control terminal of the fourth thyristor is connected to the control terminal of the fifth thyristor and the IO13 terminal of the first controller, and the control terminal of the third thyristor is connected to the control terminal of the sixth thyristor and the IO12 terminal of the first controller.

[0019] As a further embodiment of the present invention: the high-voltage conversion module includes a first diode, a fifth capacitor, a second diode, a sixth capacitor, a seventh capacitor, a fifth power transistor, a sixth power transistor, a seventh power transistor, and an eighth power transistor;

[0020] Preferably, the anode of the first diode is connected to the second terminal of the first switching transistor, the cathode of the second diode, and one end of the sixth capacitor, and is connected to the drain of the fifth power transistor and the second terminal of the third thyristor through the seventh capacitor. The source of the fifth power transistor is connected to the cathode of the first diode and the cathode of the sixth power transistor, and is connected to the anode of the second diode, the source of the seventh power transistor, and the drain of the eighth power transistor through the fifth capacitor. The source of the eighth power transistor is connected to the other end of the sixth capacitor and the first terminal of the sixth thyristor. The anode of the sixth power transistor is connected to the drain of the seventh power transistor and the second terminal of the secondary side of the second coupled inductor. The gates of the fifth power transistor, the sixth power transistor, the seventh power transistor, and the eighth power transistor are respectively connected to the IO5, IO6, IO7, and IO8 terminals of the first controller.

[0021] As a further embodiment of the present invention: the backup power module includes a ninth power transistor, a tenth power transistor, and a backup power supply.

[0022] Preferably, the drain of the ninth power transistor is connected to the first end of the primary side of the first coupling inductor, the source of the ninth power transistor is connected to the source of the tenth power transistor, the drain of the tenth power transistor is connected to the first end of the backup power supply, the second end of the backup power supply is connected to the second DC end of the first bidirectional converter, and the gates of the ninth power transistor and the tenth power transistor are respectively connected to the IO9 and IO10 ends of the first controller.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: The AC / DC hybrid microgrid power intelligent management circuit of the present invention can control the high-voltage conversion module and the low-voltage conversion module to step down the power of the DC bus and store it in the backup power module. When there is an imbalance between the AC bus and the DC bus, AC and DC power interaction is performed. When both the AC bus and the DC bus have insufficient power, the low-voltage conversion module and the high-voltage conversion module are controlled to start the boost mode and cooperate with the backup power module to maintain power interaction. If the backup power module is low voltage, the power voltage output of the low-voltage conversion module will be increased and the AC power module will be controlled to transmit the AC power provided by the distribution network. When the distribution network is without power, the high-voltage conversion module can be controlled to distribute power to the AC power module or the DC power module according to the power distribution priority. If the backup power module is without power, the AC power module will be controlled to transmit the AC power provided by the distribution network and maintain power interaction. Power balance can be maintained, and the power voltage gain state can be automatically adjusted according to the power state during power interaction to meet the power demand of the DC bus and the AC bus under different power states. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic block diagram of an AC / DC hybrid microgrid power intelligent management circuit provided in an embodiment of the present invention.

[0026] Figure 2 The circuit diagram is provided for an embodiment of the present invention of an AC / DC hybrid microgrid power intelligent management circuit.

[0027] Figure 3 The circuit diagram of the high-voltage conversion module provided in the embodiment of the present invention.

[0028] Figure 4 A circuit diagram of a backup power module provided in an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] In one embodiment, see Figure 1 A hybrid AC / DC microgrid power management circuit includes: an AC power module 1, a low-voltage conversion module 2, a DC power module 3, a high-voltage conversion module 4, a backup power module 5, and a microcontroller module 6.

[0031] AC power module 1 is connected to DC power module 3 and is used to access AC power provided by AC bus, access AC power provided by distribution network and control the transmission of power, rectify and filter AC power and output first power, and invert and filter third power or DC power transmitted by DC power module 3 and input it into AC bus or distribution network.

[0032] The low-voltage conversion module 2 is connected to the backup power module 5 and the high-voltage conversion module 4. It is used to select the series coupling degree. When the boost mode is started, the backup power provided by the backup power module 5 is series coupled and isolated for transformation and output as the second power. When the buck mode is started, the fourth power output by the high-voltage conversion module 4 is isolated, stepped down and rectified and output as charging power.

[0033] The high-voltage conversion module 4 is connected to the AC power supply module 1 and the DC power supply module 3. When the boost mode is started, it controls the multiple capacitors to alternately store and discharge the second electrical energy, performs voltage clamping, equalization boost and rectification and outputs the third electrical energy. When the buck mode is started, it performs buck, phase shift control and inversion processing on the DC power provided by the DC power supply module 3 and outputs the fourth electrical energy.

[0034] DC power module 3 is used to transmit the third electrical energy or the first electrical energy to the DC bus, receive the DC power provided by the DC bus and control the transmission status of the DC power, and transmit the third electrical energy or DC power to AC power module 1.

[0035] Backup power module 5 is used to store charging energy, release the stored energy, and provide backup power.

[0036] The microcontroller module 6 is connected to the AC power module 1, low-voltage conversion module 2, DC power module 3, high-voltage conversion module 4, and backup power module 5. It controls the high-voltage conversion module 4 and low-voltage conversion module 2 to start buck mode and controls the backup power module 5 to store energy. When there is an imbalance on the AC or DC bus, it controls the power transmission and inverter status of the AC power module 1 to complete the power exchange between the AC power module 1 and the DC power module 3. When both the AC and DC buses are underpowered, it controls the backup power module 5 to discharge, controls the low-voltage conversion module 2 and high-voltage conversion module 4 to start boost mode and maintain power exchange. If the backup power is at a low voltage, it increases the voltage output of the low-voltage conversion module 2 and controls the AC power module 1 to transmit AC power provided by the distribution network. When the distribution network is without power, it controls the high-voltage conversion module 4 to distribute power to the AC power module 1 or DC power module 3 according to the power distribution priority of the AC and DC buses. If the backup power module 5 is without power, it controls the AC power module 1 to transmit AC power provided by the distribution network and maintain power exchange.

[0037] In a specific embodiment, the AC power module 1 can be an AC power circuit composed of an AC bus interface, a bidirectional converter, a circuit breaker, and a distribution network interface. It can connect to AC power provided by the AC bus and the distribution network, control the transmission status of the AC power provided by the distribution network, perform AC power supplementation, invert the AC power, control the power interaction with the DC power module 3, and invert the DC power provided by the DC power module 3. The low-voltage conversion module 2 can be a low-voltage conversion circuit composed of coupled inductors, field-effect transistors, capacitors, and thyristors. It performs series coupling and isolation transformation on the power provided by the backup power module 5, and can also change the degree of series coupling. Specifically, it performs series coupling boosting through dual capacitors and dual coupled inductors. It can also perform isolation step-down and synchronous rectification on the power provided by the high-voltage conversion module 4. The DC power module 3 can be a thyristor. The DC power supply circuit, composed of a DC bus interface, can be connected to the DC bus to provide and connect DC power, and can also transmit the power output from the high-voltage conversion module 4 to the AC power supply module 1. The high-voltage conversion module 4 can be a high-voltage conversion circuit composed of field-effect transistors, capacitors, and diodes. By controlling the alternating energy storage and discharge states of multiple capacitors, it can perform voltage clamping, equalization boosting, and rectification of AC power when starting the boost mode, and perform voltage reduction, phase shift control, and inversion of DC power when starting the buck mode. The backup power supply module 5 can be a backup power supply circuit composed of field-effect transistors and a backup power supply for energy storage and discharge. The microcontroller module 6 can be a microcontroller circuit composed of a single-chip microcomputer, integrating arithmetic unit, controller, memory, and input / output devices, etc., to realize functions such as signal processing, data storage, module control, and timing control.

[0038] In this embodiment, please refer to Figure 2 , Figure 3 and Figure 4 The AC power module 1 includes an AC bus interface, a first circuit breaker K1, a distribution network interface, a first bidirectional converter T1, a first capacitor C1, and a second circuit breaker K2; the DC power module 3 includes a DC bus interface.

[0039] Specifically, the first end of the AC bus interface is connected to the first end of the first circuit breaker K1 and the first AC end of the first bidirectional converter T1; the second end of the AC bus interface is connected to the second end of the first circuit breaker K1 and the second AC end of the first bidirectional converter T1; the third end of the AC bus interface is connected to the third end of the first circuit breaker K1 and the third AC end of the first bidirectional converter T1; the fourth, fifth, and sixth ends of the first circuit breaker K1 are respectively connected to the first, second, and third ends of the distribution network interface; the first DC end of the first bidirectional converter T1 is connected to the first end of the second circuit breaker K2 and is connected to the second DC end of the first bidirectional converter T1 and the second end of the second circuit breaker K2 through the first capacitor C1; the third and fourth ends of the second circuit breaker K2 are respectively connected to the first and second ends of the DC bus interface.

[0040] In a specific embodiment, the first circuit breaker K1 can perform synchronous on / off control of three sets of lines, and the second circuit breaker K2 can perform synchronous on / off control of two sets of lines. The microcontroller module 6 provides a high-level signal to the control terminal of the first circuit breaker K1 or the control terminal of the second circuit breaker K2, thereby controlling the energizing state of the first circuit breaker K1 or the second circuit breaker K2. The first bidirectional converter T1 can be composed of three sets of inductors and a bidirectional inverter. The three-phase inverter is composed of six sets of diodes and six sets of IGBTs for rectification or inversion.

[0041] Furthermore, the low-voltage conversion module 2 includes a first coupling inductor B1, a second power transistor Q2, a fourth capacitor C4, a fourth power transistor Q4, a third capacitor C3, a first power transistor Q1, a third power transistor Q3, a second capacitor C2, and a second coupling inductor B2; the microcontroller module 6 includes a first controller U1;

[0042] Specifically, the first end of the primary side of the first coupling inductor B1 is connected to the first end of the primary side of the second coupling inductor B2 and one end of the second capacitor C2. The second end of the primary side of the first coupling inductor B1 is connected to the source of the second power transistor Q2. The drain of the second power transistor Q2 is connected to the second end of the secondary side of the first coupling inductor B1 and is connected to the source of the fourth power transistor Q4, the drain of the third power transistor Q3, and the second end of the primary side of the second coupling inductor B2 through the fourth capacitor C4. The first end of the secondary side of the first coupling inductor B1 is connected to the first end of the secondary side of the second coupling inductor B2. The drain of the fourth power transistor Q4 is connected to the source of the third power transistor Q3, the source of the first power transistor Q1, the other end of the second capacitor C2, and the second DC terminal of the first bidirectional converter T1 through the third capacitor C3. The gates of the first power transistor Q1, the second power transistor Q2, the third power transistor Q3, and the fourth power transistor Q4 are respectively connected to the IO1, IO2, IO3, and IO4 terminals of the first controller U1.

[0043] In a specific embodiment, the first power transistor Q1, the second power transistor Q2, the third power transistor Q3, and the fourth power transistor Q4 can all be N-channel field-effect transistors with a body diode and a body capacitor. The first power transistor Q1 controls the discharge state of the first coupling inductor B1, the second power transistor Q2 controls the energy storage state of the first coupling inductor B1, and the third power transistor Q3 and the fourth power transistor Q4 control the energy storage and discharge states of the second coupling inductor B2, respectively. The first power transistor Q1 and the second power transistor Q2 are complementaryly turned on, and the third power transistor Q3 and the fourth power transistor Q4 are complementaryly turned on. The first controller U1 can be an STM32 microcontroller.

[0044] Furthermore, the low-voltage conversion module 2 also includes a first thyristor S1, a second thyristor S2, and a first inverter J1;

[0045] Specifically, the first terminal of the first thyristor S1 is connected to the drain of the second power transistor Q2, the second terminal of the first thyristor S1 is connected to one terminal of the second thyristor S2, the other terminal of the second thyristor S2 is connected to the source of the third power transistor Q3, the control terminal of the first thyristor S1 is connected to the output terminal of the first inverter J1, and the input terminal of the first inverter J1 is connected to the control terminal of the second thyristor S2 and the IO11 terminal of the first controller U1.

[0046] In a specific embodiment, both the first and second switching transistors can be bidirectional thyristors; the first inverter J1 can be a NOT gate.

[0047] Furthermore, the DC power supply module 3 also includes a third thyristor S3, a fourth thyristor S4, a fifth thyristor S5, and a sixth thyristor S6;

[0048] Specifically, the first end of the third thyristor S3 is connected to the first DC terminal of the first bidirectional converter T1, the second end of the third thyristor S3 is connected to one end of the fourth thyristor S4, the other end of the fourth thyristor S4 is connected to the first terminal of the DC bus interface, one end of the fifth thyristor S5 is connected to the second terminal of the DC bus interface, the other end of the fifth thyristor S5 is connected to the first end of the sixth thyristor S6, the second end of the sixth thyristor S6 is connected to the second DC terminal of the first bidirectional converter T1, the control terminal of the fourth thyristor S4 is connected to the control terminal of the fifth thyristor S5 and the IO13 terminal of the first controller U1, and the control terminal of the third thyristor S3 is connected to the control terminal of the sixth thyristor S6 and the IO12 terminal of the first controller U1.

[0049] In a specific embodiment, the third thyristor S3, the fourth thyristor S4, the fifth thyristor S5, and the sixth thyristor S6 can all be bidirectional thyristors.

[0050] Furthermore, the high-voltage conversion module 4 includes a first diode D1, a fifth capacitor C5, a second diode D2, a sixth capacitor C6, a seventh capacitor C7, a fifth power transistor Q5, a sixth power transistor Q6, a seventh power transistor Q7, and an eighth power transistor Q8.

[0051] Specifically, the anode of the first diode D1 is connected to the second terminal of the first switching transistor, the cathode of the second diode D2, and one end of the sixth capacitor C6, and is connected to the drain of the fifth power transistor Q5 and the second terminal of the third thyristor S3 through the seventh capacitor C7. The source of the fifth power transistor Q5 is connected to the cathode of the first diode D1 and the cathode of the sixth power transistor Q6, and is connected to the anode of the second diode D2, the source of the seventh power transistor Q7, and the drain of the eighth power transistor Q8 through the fifth capacitor C5. The source of the eighth power transistor Q8 is connected to the other end of the sixth capacitor C6 and the first terminal of the sixth thyristor S6. The anode of the sixth power transistor Q6 is connected to the drain of the seventh power transistor Q7 and the second terminal of the secondary side of the second coupling inductor B2. The gates of the fifth power transistor Q5, the sixth power transistor Q6, the seventh power transistor Q7, and the eighth power transistor Q8 are respectively connected to the IO5, IO6, IO7, and IO8 terminals of the first controller U1.

[0052] In a specific embodiment, the fifth power transistor Q5, the sixth power transistor Q6, the seventh power transistor Q7, and the eighth power transistor Q8 can all be N-channel field-effect transistors with body diodes and body capacitors. The fifth power transistor Q5 and the sixth power transistor Q6 are a pair of complementary conducting switches, and the seventh power transistor Q7 and the eighth power transistor Q8 are another pair of complementary conducting switches. The duty cycle is fixed at 0.5 and phase-shift control is used.

[0053] Furthermore, the backup power module 5 includes a ninth power transistor Q9, a tenth power transistor Q10, and a backup power supply;

[0054] Specifically, the drain of the ninth power transistor Q9 is connected to the first end of the primary side of the first coupling inductor B1, the source of the ninth power transistor Q9 is connected to the source of the tenth power transistor Q10, the drain of the tenth power transistor Q10 is connected to the first end of the backup power supply, the second end of the backup power supply is connected to the second DC end of the first bidirectional converter T1, and the gates of the ninth power transistor Q9 and the tenth power transistor Q10 are respectively connected to the IO9 and IO10 ends of the first controller U1.

[0055] In a specific embodiment, both the ninth power transistor Q9 and the tenth power transistor Q10 can be N-channel MOSFETs; the backup power supply can be a storage battery.

[0056] The working principle of the AC / DC hybrid microgrid intelligent power management circuit of the present invention is as follows: An AC bus interface, a DC bus interface, and a distribution network interface are connected to the AC bus, DC bus, and distribution network, respectively. The IO13 terminal of the first controller U1 controls the conduction of the fourth thyristor S4 and the fifth thyristor S5, thereby transmitting the DC power provided by the DC bus to the high-voltage conversion module 4. The first controller U1 then activates the step-down mode. The IO5 and IO6 terminals of the first controller U1 respectively control the complementary conduction of the fifth power transistor Q5 and the sixth power transistor Q6, and the IO7 and IO8 terminals respectively control the complementary conduction of the seventh power transistor Q7 and the eighth power transistor Q8. This, in conjunction with the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor, enables energy storage, discharge, and inversion. Specifically, the voltage output of the high-voltage conversion module 4 is made to lead the input voltage of the low-voltage conversion module 2, forcing power to flow from the high-voltage side to the low-voltage side. The power is then isolated and transformed through the first coupling inductor B1 and the second coupling inductor B2, and supplied in parallel. The first controller U1 controls the conduction states of the first power transistor Q1, the second power transistor Q2, the third power transistor Q3, and the fourth power transistor Q4, which, together with the body diodes on the power transistors, complete the rectification process before outputting charging energy. The IO9 terminal of the first controller U1 controls the ninth power transistor Q9 to conduct, thereby controlling the backup power supply for energy storage. When an imbalance occurs on the AC bus or DC bus, the first controller U1 controls the second circuit breaker K2 to close. If the AC bus is unbalanced... The first controller U1 controls the first bidirectional converter T1 to perform inverter filtering and compensate the AC bus for power. If the DC bus is unbalanced, the rectified power from the first bidirectional converter T1 will compensate the DC bus for power, completing the power exchange between AC power module 1 and DC power module 3. When both the AC and DC buses are underpowered, the IO10 terminal of the first controller U1 controls the tenth power transistor Q10 to conduct, and the backup power supply discharges. The first controller U1 starts the boost mode, controlling the conduction states of the first power transistor Q1 and the second power transistor Q2, and the third power transistor Q3 and the fourth power transistor Q4 to control the first coupling inductor B1 and the second coupling inductor B2 for series coupling and isolation. The transformer processes and outputs a second electrical energy. Simultaneously, during the positive half-cycle of the second electrical energy cycle, the first controller U1 controls the complementary conduction states of the first power transistor Q1 and the second power transistor Q2. During the negative half-cycle, it controls the complementary conduction states of the third power transistor Q3 and the fourth power transistor Q4 for synchronous rectification. This, combined with the series energy storage and discharge of the seventh capacitor C7 and the sixth capacitor C6, and the individual energy storage and discharge of the fifth capacitor C5, provides a third electrical energy to the DC bus. Simultaneously, by controlling the closing of the second circuit breaker K2, AC and DC bus electrical energy exchange occurs. If the backup power supply is at a low voltage (the low voltage limit can be set according to user requirements), the IO11 terminal of the first controller U1 will control the second thyristor S2 to conduct, while the first thyristor S1 will be cut off.This causes the primary windings of the fourth capacitor C4, the third capacitor C3, the first coupling inductor B1, and the second coupling inductor B2 to be coupled in series. The DC bus is then powered through the high-voltage conversion module 4. At this time, the second circuit breaker K2 is disconnected, and the first circuit breaker K1 is closed, controlling the AC power supplied by the distribution network to the AC bus. If there is no power in the distribution network, the high-voltage conversion module 4 can distribute power to either the AC power module 1 or the DC power module 3 according to the power distribution priority of the AC bus and the DC bus. That is, when the power distribution priority of the AC bus is higher, the IO12 terminal of the first controller U1 will control the third thyristor. When S3 and the sixth thyristor S6 are turned on, the electrical energy output from the high-voltage conversion module 4 is processed by the first bidirectional converter T1 and then transmitted to the AC bus. Similarly, when the DC bus has priority in power distribution, the fourth thyristor S4 and the fifth thyristor S5 are turned on to supply power to the DC bus. If the backup power supply is unavailable, the first controller U1 will control the first circuit breaker K1 and the second circuit breaker K2 to turn on, transmitting the AC power provided by the distribution network to the AC bus, which is then processed and transmitted to the DC bus, maintaining power interaction and thus maintaining power balance to meet the power needs of the DC bus and AC bus under different power conditions.

[0057] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0058] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A hybrid AC / DC microgrid power intelligent management circuit, characterized in that, The circuit includes: The AC power module is connected to the DC power module and is used to access AC power provided by the AC bus, access AC power provided by the distribution network and control the transmission of power. It rectifies and filters the AC power and outputs the first power. It inverts and filters the third power or DC power transmitted by the DC power module and transmits it to the AC bus or distribution network. The low-voltage conversion module, connected to the backup power module and the high-voltage conversion module, is used to select the degree of series coupling. When the boost mode is started, it performs series coupling and isolation transformation on the backup power provided by the backup power module and outputs the second power. When the buck mode is started, it isolates, steps down, and rectifies the fourth power output by the high-voltage conversion module and outputs charging power. The high-voltage conversion module is connected to the AC power module and the DC power module. When the boost mode is started, it controls multiple capacitors to alternately store and discharge the second electrical energy, performs voltage clamping, equalization boost and rectification, and outputs the third electrical energy. When the buck mode is started, it performs buck, phase shift control and inversion processing on the DC power provided by the DC power module and outputs the fourth electrical energy. The DC power module is used to transmit the third or first electrical energy to the DC bus, receive the DC power provided by the DC bus and control the transmission status of the DC power, and transmit the third or DC power to the AC power module. The backup power module is used to store charging energy, release the stored energy, and provide backup power. The microcontroller module connects to the AC power module, low-voltage conversion module, DC power module, high-voltage conversion module, and backup power module. It controls the high-voltage and low-voltage conversion modules to start buck mode and the backup power module to store energy. When there is an imbalance on the AC or DC bus, it controls the power transmission and inverter status of the AC power module to complete the power exchange between the AC and DC power modules. When both the AC and DC buses are underpowered, it controls the backup power module to discharge, controls the low-voltage and high-voltage conversion modules to start boost mode and maintain power exchange. If the backup power is at low voltage, it increases the voltage output of the low-voltage conversion module and controls the AC power module to transmit AC power provided by the distribution network. When the distribution network is de-energized, it controls the high-voltage conversion module to distribute power to the AC or DC power module according to the power distribution priority of the AC and DC buses. If the backup power module is de-energized, it controls the AC power module to transmit AC power provided by the distribution network and maintain power exchange. The low-voltage conversion module includes a first coupling inductor, a second power transistor, a fourth capacitor, a fourth power transistor, a third capacitor, a first power transistor, a third power transistor, a second capacitor, and a second coupling inductor; the microcontroller module includes a first controller; The first end of the primary side of the first coupling inductor is connected to the first end of the primary side of the second coupling inductor and one end of the second capacitor. The second end of the primary side of the first coupling inductor is connected to the source of the second power transistor. The drain of the second power transistor is connected to the second end of the secondary side of the first coupling inductor and is connected to the source of the fourth power transistor, the drain of the third power transistor, and the second end of the primary side of the second coupling inductor through the fourth capacitor. The first end of the secondary side of the first coupling inductor is connected to the first end of the secondary side of the second coupling inductor. The drain of the fourth power transistor is connected to the source of the third power transistor, the source of the first power transistor, the other end of the second capacitor, and the second DC terminal of the first bidirectional converter through the third capacitor. The gates of the first power transistor, the second power transistor, the third power transistor, and the fourth power transistor are respectively connected to the IO1, IO2, IO3, and IO4 terminals of the first controller. The low-voltage conversion module also includes a first thyristor, a second thyristor, and a first inverter; The first end of the first thyristor is connected to the drain of the second power transistor, the second end of the first thyristor and one end of the second thyristor are connected to the source of the third power transistor, the control end of the first thyristor is connected to the output end of the first inverter, and the input end of the first inverter is connected to the control end of the second thyristor and the IO11 end of the first controller.

2. The intelligent AC / DC hybrid microgrid power management circuit according to claim 1, wherein, The AC power module includes an AC bus interface, a first circuit breaker, a distribution network interface, a first bidirectional converter, a first capacitor, and a second circuit breaker; the DC power module includes a DC bus interface. The first end of the AC bus interface is connected to the first end of the first circuit breaker and the first AC end of the first bidirectional converter. The second end of the AC bus interface is connected to the second end of the first circuit breaker and the second AC end of the first bidirectional converter. The third end of the AC bus interface is connected to the third end of the first circuit breaker and the third AC end of the first bidirectional converter. The fourth, fifth, and sixth ends of the first circuit breaker are respectively connected to the first, second, and third ends of the distribution network interface. The first DC end of the first bidirectional converter is connected to the first end of the second circuit breaker and is connected to the second DC end of the first bidirectional converter and the second end of the second circuit breaker through the first capacitor. The third and fourth ends of the second circuit breaker are respectively connected to the first and second ends of the DC bus interface.

3. The intelligent AC / DC hybrid microgrid power management circuit according to claim 1, wherein, The DC power supply module also includes a third thyristor, a fourth thyristor, a fifth thyristor, and a sixth thyristor; The first end of the third thyristor is connected to the first DC terminal of the first bidirectional converter, the second end of the third thyristor is connected to one end of the fourth thyristor, the other end of the fourth thyristor is connected to the first terminal of the DC bus interface, one end of the fifth thyristor is connected to the second terminal of the DC bus interface, the other end of the fifth thyristor is connected to the first end of the sixth thyristor, the second end of the sixth thyristor is connected to the second DC terminal of the first bidirectional converter, the control terminal of the fourth thyristor is connected to the control terminal of the fifth thyristor and the IO13 terminal of the first controller, and the control terminal of the third thyristor is connected to the control terminal of the sixth thyristor and the IO12 terminal of the first controller.

4. The AC / DC hybrid microgrid power intelligent management circuit according to claim 3, characterized in that, The high-voltage conversion module includes a first diode, a fifth capacitor, a second diode, a sixth capacitor, a seventh capacitor, a fifth power transistor, a sixth power transistor, a seventh power transistor, and an eighth power transistor. The anode of the first diode is connected to the second terminal of the first switching transistor, the cathode of the second diode, and one end of the sixth capacitor, and is connected to the drain of the fifth power transistor and the second terminal of the third thyristor through the seventh capacitor. The source of the fifth power transistor is connected to the cathode of the first diode and the drain of the sixth power transistor, and is connected to the anode of the second diode, the source of the seventh power transistor, and the drain of the eighth power transistor through the fifth capacitor. The source of the eighth power transistor is connected to the other end of the sixth capacitor and the first terminal of the sixth thyristor. The anode of the sixth power transistor is connected to the drain of the seventh power transistor and the second terminal of the secondary side of the second coupled inductor. The gates of the fifth power transistor, the sixth power transistor, the seventh power transistor, and the eighth power transistor are respectively connected to the IO5, IO6, IO7, and IO8 terminals of the first controller.

5. The AC / DC hybrid microgrid power intelligent management circuit according to claim 4, characterized in that, The backup power module includes a ninth power transistor, a tenth power transistor, and a backup power supply. The drain of the ninth power transistor is connected to the first end of the primary side of the first coupling inductor, the source of the ninth power transistor is connected to the source of the tenth power transistor, the drain of the tenth power transistor is connected to the first end of the backup power supply, the second end of the backup power supply is connected to the second DC end of the first bidirectional converter, and the gates of the ninth power transistor and the tenth power transistor are respectively connected to the IO9 and IO10 ends of the first controller.

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