Micro-grid power distribution device

Abstract

The utility model discloses a micro-grid power distribution device, which is characterized in that power loads connected to a plurality of power branches can comprise a mains supply network, an AC inverter, a conventional load, a UPS load, a standby generator and an energy storage inverter, each power load is directly connected to a port of the corresponding power branch, the wiring operation is simple and fast, and the wiring efficiency is high. The electric power loads can be compatible with each other through the electric power collection effect of the bus bar; each power branch is provided with a collector and a relay, so that the central circuit can effectively monitor the power utilization state of each path, and timely regulation and control are carried out according to some conventional power distribution modes; it can be understood that the micro-grid power distribution device greatly simplifies the operation of installation and wiring of a user, and meets the requirements of intelligent power distribution and energy management of a family at the same time.

Description

Technical Field

[0001] This application relates to the technical field of power grid distribution, and particularly relates to a microgrid power distribution device. Background Art

[0002] Microgrids can be divided into off-grid and grid-connected types. Grid-connected microgrids conduct two-way energy exchange with the main grid under normal conditions, while off-grid microgrids are completely independent and do not require any connection to the main grid. Existing microgrids take into account various modes of off-grid and grid-connected operation, and often set up AC ports such as energy storage inverters to connect to the mains power grid, loads, generators, etc. With the increase in the number of branch lines, various power distribution failure problems will occur. Especially when the external power grid loses power and the electrical load increases, it is often difficult to provide stable and reliable power supply.

[0003] In addition, existing microgrids also involve the needs of household power distribution, and multiple sets of circuit breakers and multiple load branches need to be installed, resulting in very complicated wiring of the microgrid, which brings a lot of inconvenience to assembly and use personnel. With the development of society, the number and types of household appliances will be increasing, and the power consumption demand will also be growing, which indicates that the demand for intelligent power distribution is becoming more and more vigorous. Existing microgrids still have many problems, such as inability to be compatible with multiple load branches, inability to effectively monitor the power consumption status of each load branch, and complex operation of user installation and wiring. The emergence of these problems makes it difficult for microgrids to meet the requirements of intelligent power distribution. Summary of the Invention

[0004] To solve some problems existing in the existing microgrids, this application provides a microgrid power distribution device.

[0005] In an embodiment of this application, the microgrid power distribution device includes:

[0006] A busbar for collecting and transmitting electric energy; a plurality of power branches, all connected to the busbar, for respectively connecting to a plurality of power loads; a collector and a relay are arranged on each power branch, the collector is used for collecting the electric energy information of the power branch where it is located, and the relay is used for connecting or disconnecting the power branch where it is located; a central circuit, which is signal-connected to the collectors and relays arranged on each power branch, for obtaining the electric energy signals of the corresponding power branches from the collectors, and sending drive signals to the relays.

[0007] Further, the plurality of power loads include multiple ones of a mains power network, an AC inverter, a conventional load, a UPS load, a standby generator, and an energy storage inverter; wherein, the energy storage inverter is used for electrically connecting to a photovoltaic module and / or a battery; a circuit breaker is also arranged on each power branch, and the circuit breaker is used for fusing the power branch where it is located in case of overload or short circuit.

[0008] Further, the central circuit includes a DC power supply circuit, and the DC power supply circuit includes a rectifier and a voltage regulator circuit. The rectifier is used to obtain AC electrical energy from the busbar and rectify it into DC electrical energy. The voltage regulator circuit is used to obtain DC electrical energy from the rectifier and convert it into multiple levels of direct current. The voltage regulator circuit includes a voltage regulator chip U1, a voltage regulator chip U39, an operational amplifier U25A, and an operational amplifier U25D. The voltage regulator chip U1 has a BOOT terminal, a VIN terminal, an EN terminal, an SS terminal, a VSENSE terminal, a COMP terminal, a GND terminal, and a PH terminal. Among them, the VIN terminal of the voltage regulator chip U1 is connected to the rectifier and obtains +12V DC electrical energy, and is grounded through the parallel-connected capacitors C768, C764, and C9 respectively, and is grounded through the series-connected resistors R1015 and R1022. The connection terminal of the resistors R1015 and R1022 is connected to the EN terminal of the voltage regulator chip U1. The SS terminal of the voltage regulator chip U1 is grounded through the capacitor C763. The BOOT terminal of the voltage regulator chip U1 is grounded through the capacitors C752, inductor L17, resistor R1013, resistor R1020, and resistor R1024 arranged in series. The connection terminal of the capacitor C752 and the inductor L17 is connected to the PH terminal of the voltage regulator chip U1 and is connected to the GND terminal of the voltage regulator chip U1 through the diode D127. The connection terminal of the inductor L17 and the resistor R1013 is connected to the GND terminal of the voltage regulator chip U1 through the parallel-connected capacitors C756, C755, and C753. The connection terminal of the resistor R1013 and the resistor R1020 is connected to the VSENSSE terminal of the voltage regulator chip U1. The COMP terminal of the voltage regulator chip U1 is grounded through the series-connected resistor R1017 and capacitor C767, and is grounded through the capacitor C765. The connection terminal of the inductor L17 and the resistor R1013 is used to generate +5V DC power of the voltage regulator circuit. The voltage regulator chip U39 includes a Vin terminal, a Vout terminal, and a GND terminal. Among them, the Vin terminal of the voltage regulator chip U39 obtains +5V DC power of the voltage regulator circuit, and is grounded through the parallel-connected capacitors C268, C269, and C7. The Vout terminal of the voltage regulator chip U39 is grounded through the parallel-connected capacitors C272, C271, C140, C167, and C270, and is grounded through the series-connected LED1 and resistor R5. The GND terminal of the voltage regulator chip U39 is directly grounded. The Vout terminal of the voltage regulator chip U39 is used to generate +3.3V DC power supply; the non-inverting input terminal of operational amplifier U25A obtains the +5V DC power supply of the voltage stabilizing circuit through the series-connected resistors R167 and R158. The connection terminal of resistors R158 and R167 is grounded through the series-connected resistors R166 and R174, and is also grounded through the parallel-connected diode U16 and capacitor C174. The other end of resistor R158 is grounded through the parallel-connected capacitors C111 and C109. The inverting input terminal of operational amplifier U25A is grounded through the parallel-connected diode ZD18, capacitors C160, C340, C162, and C341. And the inverting input terminal of operational amplifier U25A is connected to the output terminal of operational amplifier U25A through resistor R164; the non-inverting input terminal of operational amplifier U25D is connected to the connection terminal of resistor R158 and resistor R168 through capacitor R326. The inverting input terminal of operational amplifier U25D is grounded through the parallel-connected capacitors C344, C107, C342, and C343. And the inverting input terminal of operational amplifier U25D is connected to the output terminal of operational amplifier U25D through resistor R175; the inverting input terminal of operational amplifier U25A is used to generate the +3VAP DC power supply of the voltage stabilizing circuit, and the inverting input terminal of operational amplifier U25D is used to generate the +3VB DC power supply of the voltage stabilizing circuit.

[0009] Further, the central circuit further includes a single-chip microcomputer U41. The single-chip microcomputer U41 includes PC14 terminal, PC15 terminal, OSC-IN terminal, OSC-OUT terminal, VSS terminal, and VDD terminal; a crystal oscillator XL4 is connected between the PC14 terminal and PC15 terminal of the single-chip microcomputer U41. The crystal oscillator XL4 is in parallel with the sequentially connected resistors C259 and C262, and the connection terminal of resistors C259 and C262 is grounded; a crystal oscillator XL1 is connected between the OSC-IN terminal and OSC-OUT terminal of the single-chip microcomputer U41. The crystal oscillator XL1 is in parallel with the sequentially connected resistors C285 and C287, and the connection terminal of resistors C285 and C287 is grounded; the VSS terminal of the single-chip microcomputer U41 is grounded, and the VDD terminal of the single-chip microcomputer U41 obtains the +3.3V DC power supply from the voltage stabilizing circuit; the single-chip microcomputer U41 further includes PC0 terminal, PC1 terminal, PC2 terminal, PC3 terminal, PA0 terminal, and PA1 terminal, which are used to obtain the power signals of multiple power branches regarding voltage respectively; the single-chip microcomputer U41 further includes PA2 terminal, PA3 terminal, PA4 terminal, PA5 terminal, PA6 terminal, PA7 terminal, PC4 terminal, PC5 terminal, PB0 terminal, and PB1 terminal, which are used to obtain the power signals of multiple power branches regarding current respectively; the single-chip microcomputer U41 further includes PE7 terminal, PE8 terminal, PE9 terminal, PE10 terminal, PE11 terminal, PE13 terminal, PE14 terminal, and PE15 terminal, which are used to send drive signals to the relays in multiple power branches respectively.

[0010] Further, one of the multiple electrical loads is a mains power network represented by GRID. The collector on the power branch connected to the mains power network includes a mains voltage acquisition circuit and a mains current acquisition circuit. The mains voltage acquisition circuit includes operational amplifiers U4C and U8B. The non-inverting terminal of operational amplifier U4C is connected to one power line of the power branch where the mains power network is located through resistor R17, and is grounded through the parallel-connected capacitor C335 and resistor R21. The inverting terminal of operational amplifier U4C is connected to the other power line of the power branch where the mains power network is located through resistor R14, and is connected to the output terminal of operational amplifier U4C through the parallel-connected capacitor C332 and resistor R1099. The output terminal of operational amplifier U4C is connected to the non-inverting terminal of operational amplifier U8B through resistor R1102. The non-inverting terminal of operational amplifier U8B is connected to the +3VB DC power supply of the voltage stabilizing circuit through the parallel-connected capacitor C27 and resistor R36, and is grounded through capacitor C98. The inverting terminal of operational amplifier U8B is connected to the output terminal of operational amplifier U8B. The output terminal of operational amplifier U8B is grounded through the series-connected resistor R79 and capacitor C70. The connection terminal of resistor R79 and capacitor C70 is connected to the PC0 terminal of microcontroller U41. The PC0 terminal of microcontroller U41 is configured to obtain the voltage of the power branch where the mains power network is located. The mains current acquisition circuit includes operational amplifiers U5D, U6D, and U17B. The non-inverting terminal of operational amplifier U5D is connected to one side of one power line of the power branch where the mains power network is located through resistor R91, and is grounded through the parallel-connected capacitor C36 and resistor R115. The inverting terminal of operational amplifier U5D is connected to the other side of the same power line of the power branch where the mains power network is located through resistor R82, and is connected to the output terminal of operational amplifier U5D through the parallel-connected capacitor C31 and resistor R71. The output terminal of operational amplifier U5D is connected to the non-inverting terminal of operational amplifier U17B through resistor R49, and one end of resistor R49 is connected to the +3VB DC power supply of the voltage stabilizing circuit through the series-connected capacitor C149 and resistor R57. The non-inverting terminal of operational amplifier U6D is connected to one side of the other power line of the power branch where the mains power network is located through resistor R89, and is grounded through the parallel-connected capacitor C37 and resistor R113. The inverting terminal of operational amplifier U6D is connected to the other side of the same power line of the power branch where the mains power network is located through resistor R83, and is connected to the output terminal of operational amplifier U6D through the parallel-connected capacitor C29 and resistor R193. The output terminal of operational amplifier U6D is connected to the non-inverting terminal of operational amplifier U17B through resistor R47, and one end of resistor R47 is connected to the +3VB DC power supply of the voltage stabilizing circuit through the series-connected resistor R195 and capacitor C146.The non-inverting input terminal of operational amplifier U17B is grounded through capacitor C143. The inverting input terminal of operational amplifier U17B is connected to the output terminal of operational amplifier U17B. The output terminal of operational amplifier U17B is grounded through resistor R3 and capacitor C4 connected in series. The connection terminal of resistor R3 and capacitor C4 is connected to the PA2 terminal of microcontroller U41, and the PA2 terminal of microcontroller U41 is configured to acquire the current of the power branch where the mains network is located.;

[0011] Further, the central circuit further includes a zero-crossing voltage detection circuit for the power branch where the mains network is located. The zero-crossing voltage detection circuit includes operational amplifier U27C. The inverting input terminal of operational amplifier U27C is connected to the non-inverting input terminal of operational amplifier U8B in the mains voltage acquisition circuit through resistor R163 and is grounded through capacitor C53. The non-inverting input terminal of operational amplifier U27C is connected to the +3VAP DC power supply of the voltage stabilization circuit through resistor R188, is grounded through capacitor C56 and resistor R97 connected in parallel, and is connected to the output terminal of operational amplifier U27C through resistor R61. The output terminal of operational amplifier U27C is connected to the +3.3V DC power supply of the voltage stabilization circuit through resistor R52 and is grounded through resistor R55 and capacitor C51 connected in series. The microcontroller U41 further includes a PB10 terminal. The PB10 terminal of microcontroller U41 is connected to the connection terminal of resistor R55 and capacitor C51 and is configured to acquire the zero-crossing voltage signal of the power branch where the mains network is located.

[0012] Further, the central circuit further includes a relay drive circuit, and the relay drive circuit includes a voltage regulator chip U24; the voltage regulator chip U24 includes 1A1 terminal, 1A2 terminal, 1A3 terminal, 1A4 terminal, 2A1 terminal, 2A2 terminal, 2A3 terminal, 2A4 terminal, 1Y1 terminal, 1Y2 terminal, 1Y3 terminal, 1Y4 terminal, 2Y1 terminal, 2Y2 terminal, 2Y3 terminal, 2Y4 terminal, VCC terminal, GND terminal, 1OE terminal, and 2OE terminal; the 1A1 terminal, 1A2 terminal, 1A3 terminal, 1A4 terminal, 2A1 terminal, 2A2 terminal, 2A3 terminal, and 2A4 terminal of the voltage regulator chip U24 are respectively grounded through capacitors C161, C108, C106, C92, C91, C60, C58, and C57 arranged one-to-one, and are respectively connected to the PE11 terminal, PE13 terminal, E14 terminal, PE15 terminal, PE7 terminal, PE8 terminal, PE9 terminal, and PE10 terminal of the single-chip microcomputer U41 through resistors R11, R23, R31, R41, R43, R45, R59, and R62 arranged one-to-one. The PE11 terminal, PE13 terminal, E14 terminal, PE15 terminal, PE7 terminal, PE8 terminal, PE9 terminal, and PE10 terminal of the single-chip microcomputer U41 are respectively grounded through a plurality of equal-value resistors arranged one-to-one; the 1Y1 terminal, 1Y2 terminal, 1Y3 terminal, 1Y4 terminal, 2Y1 terminal, 2Y2 terminal, 2Y3 terminal, and 2Y4 terminal of the voltage regulator chip U24 are respectively connected to the relays arranged in the plurality of DC powers one-to-one, and are respectively grounded through a plurality of equal-value resistors arranged one-to-one; the 1OE terminal and 2OE terminal of the voltage regulator chip U24 are both grounded, the VCC terminal of the voltage regulator chip U24 is connected to the +5V DC power of the voltage regulator circuit, and is grounded through the capacitor C55, and the GND terminal of the voltage regulator chip U24 is grounded; the voltage regulator chip U24 is used to convert the drive signal output by the single-chip microcomputer U41 into a voltage signal recognizable by the relay.

[0013] Further, one of the multiple electrical loads is a mains power network represented by GRID, and one of the multiple electrical loads is a UPS load represented by UPS. The central circuit further includes a multiplexing circuit, and the multiplexing circuit includes a multiplexing chip U13. The microcontroller U41 further includes a PE6 terminal and a PE5 terminal for respectively outputting signals for multiplexing enabling. The multiplexing chip U13 includes a 1B1 terminal, a 1B2 terminal, a 1B3 terminal, a 1B4 terminal, a 2B1 terminal, a 2B2 terminal, a 2B3 terminal, a 2B4 terminal, a 1A terminal, a 2A terminal, an S0 terminal, an S1 terminal, an OE terminal, a 2OE terminal, a VCC terminal, and a GND terminal. The 1B1 terminal and the 1B3 terminal of the multiplexing chip U13 are respectively connected to a power line of the power branch where the mains power network is located through equivalent resistors. The 1B2 terminal and the 1B4 terminal of the multiplexing chip U13 are respectively connected to another power line of the power branch where the mains power network is located through equivalent resistors. The 1B1 terminal, the 1B2 terminal, the 1B3 terminal, and the 1B4 terminal of the multiplexing chip U13 are respectively grounded through capacitors C97, C67, C68, and C73 provided one-to-one. The 2B1 terminal and the 2B3 terminal of the multiplexing chip U13 are respectively connected to a power line of the power branch where the UPS load is located through equivalent resistors. The 2B2 terminal and the 2B4 terminal of the multiplexing chip U13 are respectively connected to another power line of the power branch where the UPS load is located through equivalent resistors. The 2B1 terminal, the 2B2 terminal, the 2B3 terminal, and the 2B4 terminal of the multiplexing chip U13 are respectively grounded through capacitors C74, C75, C76, and C77 provided one-to-one. The 1A terminal and the 2A terminal of the multiplexing chip U13 are respectively connected to the PC3 terminal and the PAO terminal of the microcontroller U41. The S0 terminal and the S1 terminal of the multiplexing chip are respectively connected to the PE6 terminal and the PE5 terminal of the microcontroller U41. The OE terminal, the GND terminal, and the 2OE terminal of the multiplexing chip U13 are grounded and connected to the S1 terminal of the multiplexing chip U13 through a capacitor C88, and connected to the S0 terminal of the multiplexing chip U13 through a capacitor C258. The VCC terminal of the multiplexing chip U13 is connected to the +3.3V DC power of the voltage stabilizing circuit and grounded through a capacitor C65. The multiplexing chip U13 can select the signal obtained from one of the 1B1 terminal and the 1B2 terminal and transmit it to the PC3 terminal of the microcontroller U41 through the 1A terminal when the signal at the S1 terminal is enabled, and can also select the signal obtained from one of the 2B1 terminal and the 2B2 terminal and transmit it to the PAO terminal of the microcontroller U41 through the 2A terminal when the signal at the S0 terminal is enabled.

[0014] Further, the central circuit further includes a dry contact relay circuit, and the dry contact relay circuit includes an optocoupler U35, a triode Q11, a triode Q8, a triode Q14, and a relay element RY1; the single-chip microcomputer U41 further includes a PE1 terminal for outputting a dry contact enable signal; the PE1 terminal of the single-chip microcomputer U41 is connected to the base of the triode Q11 through a resistor R271, the base of the triode Q11 is connected to the collector of the triode Q11 through a resistor R270, the collector of the triode Q11 is connected to an emitter of the optocoupler U35, an emitter of the optocoupler U35 is connected to another emitter of the optocoupler U35 through a diode D25 and a resistor R269 connected in parallel, and another emitter of the optocoupler U35 is connected to the +3.3V DC power supply of the voltage stabilizing circuit through a resistor R267; a receiving terminal of the optocoupler U35 is connected to the +5V DC power supply of the voltage stabilizing circuit through a resistor R266, another receiving terminal of the optocoupler U35 is connected to the base of the triode Q8 and grounded through a resistor R272, the emitters of the triode Q8 and the triode Q11 are both grounded, the collector of the triode Q8 is connected to the +5V DC power supply of the voltage stabilizing circuit through a resistor R268 and connected to the base of the triode Q14 through a resistor R276, the base of the triode Q14 is grounded through a resistor R279, the emitter of the triode Q14 is grounded, the collector of the triode Q14 is connected to the control terminal of the relay element RY1, and the control terminal of the relay element RY1 is connected to the +12V DC power supply of the voltage stabilizing circuit through a diode D26; the common contact COM1 and the normally open contact NO1 of the relay element RY1 are used to be connected in series to the power supply line of the microgrid power distribution device.

[0015] The beneficial effects of the present application are as follows:

[0016] The microgrid power distribution device according to the above embodiment mainly includes: a busbar for collecting and transmitting electric energy; a plurality of power branches are all connected to the busbar and are used to connect to a plurality of power loads respectively; a collector and a relay are arranged on each power branch; the central circuit is signal-connected to the collector and the relay arranged on each power branch, and is used to obtain the electric energy signal of the corresponding power branch from the collector and send a driving signal to the relay. In the technical solution, the power loads connected to the plurality of power branches may include multiple ones of a mains power network, an AC inverter, a conventional load, a UPS load, a standby generator, and an energy storage inverter. Each power load can be directly connected to the port of the corresponding power branch, and the wiring operation is simple and fast. Moreover, due to the power collection function of the busbar, each power load can be compatible with each other; since each power branch is equipped with a collector and a relay, the central circuit can effectively monitor the power consumption status of each path and perform timely regulation according to some conventional power distribution modes; it can be understood that the microgrid power distribution device of the present application greatly simplifies the operation of user installation and wiring, and at the same time meets the intelligent power distribution and energy management needs of families. Brief Description of the Drawings

[0017] Figure 1 It is a structural block diagram of a microgrid power distribution device in an embodiment of the present application;

[0018] Figure 2 It is one of the circuit diagrams of the voltage stabilizing circuit in an embodiment of the present application;

[0019] Figure 3 It is the second circuit diagram of the voltage stabilizing circuit in an embodiment of the present application;

[0020] Figure 4 It is the circuit diagram of the central circuit in an embodiment of the present application;

[0021] Figure 5 It is the circuit diagram of the mains voltage acquisition circuit in an embodiment of the present application;

[0022] Figure 6 It is the circuit diagram of the mains current acquisition circuit in an embodiment of the present application;

[0023] Figure 7 It is the circuit diagram of the voltage zero-crossing detection circuit in an embodiment of the present application;

[0024] Figure 8 It is the circuit diagram of the relay drive circuit in an embodiment of the present application;

[0025] Figure 9 It is the circuit diagram of the multiplexing circuit in an embodiment of the present application;

[0026] Figure 10 It is the circuit diagram of the dry contact relay circuit in an embodiment of the present application. Detailed Description of the Preferred Embodiment

[0027] In the description of the present invention, it should be understood that the described embodiments are only a part of the embodiments of the present invention, not all embodiments.

[0028] The technical solutions of the present application will be further described in detail below through some embodiments and in combination with the drawings.

[0029] Please refer to Figure 1 , the present application discloses a microgrid power distribution device, which mainly includes a busbar, a plurality of power branches and a central circuit, which will be described separately below.

[0030] The busbar is used to collect and transmit electric energy, and can be a busbar made of copper inside the device. Many power branches are connected to it, and the electric energy on the branches is collected on the busbar.

[0031] Multiple power branches are all connected to the busbar and are used to connect multiple power loads respectively. A collector and a relay are arranged on each power branch. The collector is used to collect the electrical energy information of the power branch where it is located, and the relay is used to connect or disconnect the power branch where it is located. It can be understood that the multiple power loads include multiple ones of the mains power network, AC inverter, conventional load, UPS load, standby generator, energy storage inverter; among them, the energy storage inverter is used to be electrically connected to the photovoltaic module and / or battery. In order to meet the expansion requirements of the power load, multiple energy storage inverters (such as energy storage inverter 1,..., energy storage inverter N) can be set, and multiple conventional loads (such as conventional load 1,..., conventional load N) can also be set. The UPS load can be household devices such as computers, routers, printers, etc., and the AC inverter can be an ordinary photovoltaic inverter or a micro-inverter.

[0032] The central circuit is signal-connected to the collector and the relay arranged on each power branch, and is used to obtain the electrical energy signal of the corresponding power branch from the collector and send a driving signal to the relay. For example, the central circuit obtains electrical energy signals such as voltage / current from the collector on the power branch where the mains power network is located, and can also send driving signals for turning on / off to the relay on the power branch where the mains power network is located; also for example, the central circuit obtains electrical energy signals such as voltage / current from the collector on the power branch where the standby generator is located, and can also send driving signals for turning on / off to the relay on the power branch where the standby generator is located; it can be understood that the electrical energy signal collection and relay switch control for the power branches where other power loads are located adopt the same method.

[0033] In another embodiment, refer to Figure 1 , a circuit breaker is also arranged on each power branch of the microgrid power distribution device, and the circuit breaker is used to fuse the power branch where it is located in case of overload or short circuit. The circuit breaker can be an overcurrent protection device, a fuse, an air switch, etc.

[0034] In this embodiment, the central circuit is the monitoring center of intelligent power distribution and has a relatively complex circuit structure. It needs to be powered by direct current to work normally. Therefore, the central circuit can include a direct current power supply circuit, and the direct current power supply circuit includes a rectifier and a voltage stabilizing circuit; among them, the rectifier is used to obtain alternating current electrical energy from the busbar and rectify it into direct current electrical energy, for example, to realize the function of +12V direct current output through an inverter coil and a rectifier bridge; among them, the voltage stabilizing circuit is used to obtain direct current electrical energy from the rectifier and convert it into direct current electricity of multiple levels.

[0035] Refer to Figure 2 and Figure 3, the voltage stabilizing circuit includes voltage stabilizing chip U1, voltage stabilizing chip U39, operational amplifier U25A, and operational amplifier U25D. The voltage stabilizing chip U1 has a BOOT terminal, a VIN terminal, an EN terminal, an SS terminal, a VSENSE terminal, a COMP terminal, a GND terminal, and a PH terminal. Specifically, a voltage stabilizing chip of model TPS54331 can be adopted. Among them, the VIN terminal of the voltage stabilizing chip U1 is connected to the rectifier and obtains +12V DC electrical energy, and is grounded through the parallel-connected capacitors C768, C764, and C9 respectively, and is also grounded through the series-connected resistors R1015 and R1022. The connection terminal of the resistors R1015 and R1022 is connected to the EN terminal of the voltage stabilizing chip U1. The SS terminal of the voltage stabilizing chip U1 is grounded through the capacitor C763. The BOOT terminal of the voltage stabilizing chip U1 is grounded through the capacitors C752, inductor L17, resistor R1013, resistor R1020, and resistor R1024 connected in series in sequence. The connection terminal of the capacitor C752 and the inductor L17 is connected to the PH terminal of the voltage stabilizing chip U1 and is connected to the GND terminal of the voltage stabilizing chip U1 through the diode D127. The connection terminal of the inductor L17 and the resistor R1013 is connected to the GND terminal of the voltage stabilizing chip U1 through the parallel-connected capacitors C756, C755, and C753. The connection terminal of the resistor R1013 and the resistor R1020 is connected to the VSENSSE terminal of the voltage stabilizing chip U1. The COMP terminal of the voltage stabilizing chip U1 is grounded through the series-connected resistor R1017 and capacitor C767, and is also grounded through the capacitor C765. The connection terminal of the inductor L17 and the resistor R1013 is used to generate +5V DC electricity of the voltage stabilizing circuit.

[0036] See Figure 3 , the voltage stabilizing chip U39 includes a Vin terminal, a Vout terminal, and a GND terminal. For example, a conventional three-terminal voltage stabilizing integrated circuit IC chip can be specifically adopted. Among them, the Vin terminal of the voltage stabilizing chip U39 obtains +5V DC electricity of the voltage stabilizing circuit, and is grounded through the parallel-connected capacitors C268, C269, and C7. The Vout terminal of the voltage stabilizing chip U39 is grounded through the parallel-connected capacitors C272, C271, C140, C167, and C270, and is also grounded through the series-connected LED1 and resistor R5. The GND terminal of the voltage stabilizing chip U39 is directly grounded. The Vout terminal of the voltage stabilizing chip U39 is used to generate +3.3V DC electricity of the voltage stabilizing circuit.

[0037] See Figure 3, both operational amplifiers U25A and U25D include a non-inverting input terminal, an inverting input terminal, and an output terminal. The non-inverting input terminal of operational amplifier U25A obtains the +5V DC power supply of the voltage stabilizing circuit through the serially arranged resistors R167 and R158. The connection terminal of resistors R158 and R167 is grounded through the serially arranged resistors R166 and R174, and is also grounded through the paralleled diode U16 and capacitor C174. The other end of resistor R158 is grounded through the paralleled capacitors C111 and C109. The inverting input terminal of operational amplifier U25A is grounded through the paralleled diode ZD18, capacitors C160, C340, C162, and C341, and the inverting input terminal of operational amplifier U25A is connected to the output terminal of operational amplifier U25A through resistor R164; the non-inverting input terminal of operational amplifier U25D is connected to the connection terminal of resistors R158 and R168 through capacitor R326. The inverting input terminal of operational amplifier U25D is grounded through the paralleled capacitors C344, C107, C342, and C343, and the inverting input terminal of operational amplifier U25D is connected to the output terminal of operational amplifier U25D through resistor R175; the inverting input terminal of operational amplifier U25A is used to generate the +3VAP DC power supply of the voltage stabilizing circuit, and the inverting input terminal of operational amplifier U25D is used to generate the +3VB DC power supply of the voltage stabilizing circuit.

[0038] It can be understood that the +12V DC power supply generated by the rectifier, the +5V DC power supply, +3.3V DC power supply, +3VAP DC power supply, and +3VB DC power supply generated by the voltage stabilizing circuit are used to meet the power supply requirements of the central circuit.

[0039] In this embodiment, referring to Figure 4 , the central circuit further includes a single-chip microcomputer U41, and the single-chip microcomputer U41 includes a PC14 terminal, a PC15 terminal, an OSC-IN terminal, an OSC-OUT terminal, a VSS terminal, and a VDD terminal; the single-chip microcomputer U41 can specifically adopt a chip of the STM32F107 model.

[0040] A crystal oscillator XL4 is connected between the PC14 terminal and the PC15 terminal of the single-chip microcomputer U41, and resistors C259 and C262 are connected in parallel to the crystal oscillator XL4 in sequence, and the connection terminal of resistors C259 and C262 is grounded; a crystal oscillator XL1 is connected between the OSC-IN terminal and the OSC-OUT terminal of the single-chip microcomputer U41, and resistors C285 and C287 are connected in parallel to the crystal oscillator XL1 in sequence, and the connection terminal of resistors C285 and C287 is grounded.

[0041] The VSS terminal of the microcontroller U41 is grounded, and the VDD terminal of the microcontroller U41 obtains +3.3V DC power from the voltage stabilizing circuit. The microcontroller U41 specifically includes four groups of power supply terminals (such as VSS-1, VDD-1, VSS-2, VDD-2, VSS-3, VDD-3, VSS-4, VDD-4, VSS-5, VDD-5). Each group of power supply terminals can be grounded and connected to +3.3V DC power in the same way. Moreover, a capacitor C296 can be connected in series between VSS-1 and VDD-1, a capacitor C283 can be connected in series between VSS-2 and VDD-2, a capacitor C281 can be connected in series between VSS-3 and VDD-3, a capacitor C297 can be connected in series between VSS-4 and VDD-4, and a capacitor C284 can be connected in series between VSS-5 and VDD-5.

[0042] The microcontroller U41 also includes PC0, PC1, PC2, PC3, PA0, and PA1 terminals, which are used to obtain the electrical energy signals regarding voltage of multiple power branches respectively. For example, the PC0 terminal obtains the voltage signal of the power branch where the mains power grid (GRID) is located, the PC1 terminal obtains the voltage signal of the power branch where the UPS load (UPS) is located, the PC2 terminal obtains the voltage signal of the power branch where the standby generator (GEN) is located, the PC3 terminal obtains the voltage signal of a power line in the power branch where the mains power grid (GRID) is located, the PA0 terminal obtains the voltage signal of a power line in the power branch where the UPS load (UPS) is located, and the PA1 terminal obtains the voltage signal of a power line in the power branch where the standby generator (GEN) is located.

[0043] The microcontroller U41 also includes PA2, PA3, PA4, PA5, PA6, PA7, PC4, PC5, PB0, and PB1 terminals, which are used to obtain the electrical energy signals regarding current of multiple power branches respectively. For example, the PA2 terminal obtains the current signal of a power line in the power branch where the mains power grid (GRID) is located, the PA3 terminal obtains the current signal of a power line in the power branch where the general load (LOAD) is located, the PA4 terminal obtains the current signal of a power line in the power branch where the standby generator (GEN) is located, the PA5 terminal obtains the current signal of a power line in the power branch where the UPS load (UPS) is located, and the PA6, PA7, PC4, PC5, PB0, and PB1 terminals respectively obtain the current signals of a power line in the circuit branches where the energy storage inverters 1 to N are located.

[0044] The single-chip microcomputer U41 further includes a PE7 terminal, a PE8 terminal, a PE9 terminal, a PE10 terminal, a PE11 terminal, a PE13 terminal, a PE14 terminal, and a PE15 terminal, which are used to send drive signals to the relays in multiple power branches respectively. For example, the PE7 terminal, the PE8 terminal, the PE9 terminal, the PE10 terminal, the PE14 terminal, and the PE15 terminal send drive signals to the relays in the circuit branches where the energy storage inverters 1 to N are located respectively, the PE11 terminal sends a drive signal to the relay in the power branch where the mains power grid (GRID) is located, and the PE13 terminal sends a drive signal to the relay in the power branch where the UPS load (UPS) is located.

[0045] See Figure 4 , the single-chip microcomputer U41 may further include other ports. For example, the VDDA terminal needs to be connected to the +3.3V direct current of the voltage stabilizing circuit and grounded through the capacitor C294; for example, the PE2 terminal is grounded through the resistor R406, and the BOOT0 terminal is grounded through the resistor R414. Of course, other ports of the single-chip microcomputer U41 can also be configured to output some signals to achieve the trigger setting function. For example, the PE3 terminal, the PE4 terminal, and the PC13 are set to control the LED1, LED2, LED3, etc. respectively, the NRST terminal is set to control the chip reset, the VREF terminal is set to output a reference voltage, the PB12 terminal, the PB13 terminal, the PB14 terminal, the PB15, and the PD11 terminals are set to realize the reading and writing of FLSH stored data, the PD8 terminal, the PD9 terminal, and the PD10 terminal are set to realize the WIFI signal reading, the PD12 terminal, the PD13 terminal, the PD14 terminal, the PD15 terminal, the PC6 terminal, the PC7 terminal, the PC8 terminal, the PC9 terminal, the PA8 terminal, the PA9 terminal, the PA10 terminal, the PA11 terminal, the PA12 terminal, and the PA13 terminal are set to realize the synchronous trigger configuration of the device, and the PA14 terminal, the PA15 terminal, the PC10 terminal, the PC11 terminal, the PC12 terminal, the PD0 terminal, the PD1 terminal, the PD2 terminal, the PD3 terminal, the PD4 terminal, the PD5 terminal, the PD6 terminal, the PD7 terminal, the PB3 terminal, the PB4 terminal, the PB5 terminal, the PB6 terminal, the PB7 terminal, the PB8 terminal, and the PB9 terminal are set to realize functions such as the upper computer program download, 485 communication, CAN communication, and SWD interface communication. It can be understood that the port settings and trigger configurations of the single-chip microcomputer U41 all belong to the prior art and will not be introduced in detail here.

[0046] It can be understood that the microgrid power distribution device can obtain external control signals based on rich external interfaces and obtain serial debugging signals based on the SWD interface circuit. In this way, it is beneficial to the expansion of its own functions and the device can be flexibly used in multiple products, thereby improving the compatibility during application.

[0047] In this application, one of the multiple electrical loads is the mains power network, denoted by GRID. The collector on the power branch connected to the mains power network includes a mains voltage acquisition circuit and a mains current acquisition circuit.

[0048] See Figure 5 , the mains voltage acquisition circuit includes operational amplifiers U4C and U8B; the non-inverting terminal of operational amplifier U4C is connected to one power line of the power branch where the mains power network is located through resistor R17, and is grounded through the parallel-connected capacitor C335 and resistor R21. The inverting terminal of operational amplifier U4C is connected to the other power line of the power branch where the mains power network is located through resistor R14, and is connected to the output terminal of operational amplifier U4C through the parallel-connected capacitor C332 and resistor R1099. The output terminal of operational amplifier U4C is connected to the non-inverting terminal of operational amplifier U8B through resistor R1102. The non-inverting terminal of operational amplifier U8B is connected to the +3VB DC power supply of the voltage stabilization circuit through the parallel-connected capacitor C27 and resistor R36, and is grounded through capacitor C98. The inverting terminal of operational amplifier U8B is connected to the output terminal of operational amplifier U8B. The output terminal of operational amplifier U8B is grounded through the series-connected resistor R79 and capacitor C70. The connection terminal of resistor R79 and capacitor C70 is connected to the PC0 terminal of microcontroller U41. The PC0 terminal of microcontroller U41 is configured to obtain the voltage of the power branch where the mains power network is located.

[0049] See Figure 6, the mains current acquisition circuit includes operational amplifiers U5D, U6D, and U17B; the non-inverting input terminal of operational amplifier U5D is connected to one side of a power line of the power branch where the mains network is located through resistor R91, and is grounded through the parallel-connected capacitor C36 and resistor R115. The inverting input terminal of operational amplifier U5D is connected to the other side of the same power line of the power branch where the mains network is located through resistor R82, and is connected to the output terminal of operational amplifier U5D through the parallel-connected capacitor C31 and resistor R71. The output terminal of operational amplifier U5D is connected to the non-inverting input terminal of operational amplifier U17B through resistor R49, and one end of resistor R49 is connected to the +3VB DC power supply of the voltage stabilization circuit through the series-connected capacitor C149 and resistor R57; the non-inverting input terminal of operational amplifier U6D is connected to one side of another power line of the power branch where the mains network is located through resistor R89, and is grounded through the parallel-connected capacitor C37 and resistor R113. The inverting input terminal of operational amplifier U6D is connected to the other side of the same power line of the power branch where the mains network is located through resistor R83, and is connected to the output terminal of operational amplifier U6D through the parallel-connected capacitor C29 and resistor R193. The output terminal of operational amplifier U6D is connected to the non-inverting input terminal of operational amplifier U17B through resistor R47, and one end of resistor R47 is connected to the +3VB DC power supply of the voltage stabilization circuit through the series-connected resistor R195 and capacitor C146; the non-inverting input terminal of operational amplifier U17B is grounded through capacitor C143, the inverting input terminal of operational amplifier U17B is connected to the output terminal of operational amplifier U17B, the output terminal of operational amplifier U17B is grounded through the series-connected resistor R3 and capacitor C4, and the connection terminal of resistor R3 and capacitor C4 is connected to the PA2 terminal of microcontroller U41. The PA2 terminal of microcontroller U41 is configured to acquire the current of the power branch where the mains network is located.

[0050] It should be noted that the central circuit also includes voltage acquisition circuits and current acquisition circuits for the power branches where the AC inverter, conventional load, UPS load, standby generator, and energy storage inverter are located respectively. The specific circuit structures can be referred to Figure 5 and Figure 6 , and will not be repeated here.

[0051] In this embodiment, the central circuit also includes a zero-crossing voltage detection circuit for the power branch where the mains network is located. Refer to Figure 7 , and the zero-crossing voltage detection circuit includes operational amplifier U27C.

[0052] In Figure 7In it, the inverting terminal of operational amplifier U27C is connected to the non-inverting terminal of operational amplifier U8B in the mains voltage acquisition circuit through resistor R163, and is grounded through capacitor C53. The non-inverting terminal of operational amplifier U27C is connected to the +3VAP DC power supply of the voltage stabilizing circuit through resistor R188, and is grounded through capacitors C56 and R97 connected in parallel, and is connected to the output terminal of operational amplifier U27C through resistor R61. The output terminal of operational amplifier U27C is connected to the +3.3V DC power supply of the voltage stabilizing circuit through resistor R52, and is grounded through resistors R55 and C51 connected in series; Figure 4 The single-chip microcomputer U41 in it further includes a PB10 terminal. The PB10 terminal of the single-chip microcomputer U41 is connected to the connection terminal of resistor R55 and capacitor C51, and is configured to obtain the zero-crossing signal of the voltage of the power branch where the mains network is located.

[0053] It should be noted that the central circuit further includes a zero-crossing detection circuit for the power branch where the standby generator is located. The specific circuit structure can refer to Figure 7 Moreover, Figure 4 The PB11 terminal of the single-chip microcomputer U41 in it is configured to obtain the zero-crossing signal of the voltage of the power branch where the standby generator (GEN) is located, and will not be repeated here.

[0054] In this embodiment, referring to Figure 8 the central circuit further includes a relay drive circuit. The relay drive circuit includes a voltage stabilizing chip U24. The voltage stabilizing chip U24 includes 1A1 terminal, 1A2 terminal, 1A3 terminal, 1A4 terminal, 2A1 terminal, 2A2 terminal, 2A3 terminal, 2A4 terminal, 1Y1 terminal, 1Y2 terminal, 1Y3 terminal, 1Y4 terminal, 2Y1 terminal, 2Y2 terminal, 2Y3 terminal, 2Y4 terminal, VCC terminal, GND terminal, 1OE terminal, and 2OE terminal. Specifically, a chip of model SN74HCG244 can be used.

[0055] In Figure 8 the 1A1 terminal, 1A2 terminal, 1A3 terminal, 1A4 terminal, 2A1 terminal, 2A2 terminal, 2A3 terminal, and 2A4 terminal of the voltage stabilizing chip U24 are respectively grounded through capacitors C161, C108, C106, C92, C91, C60, C58, and C57 set one-to-one, and are respectively connected to Figure 4The PE11, PE13, E14, PE15, PE7, PE8, PE9, and PE10 terminals of the microcontroller U41 are grounded through a plurality of equal-value resistors set one-to-one; the 1Y1, 1Y2, 1Y3, 1Y4, 2Y1, 2Y2, 2Y3, and 2Y4 terminals of the voltage regulator chip U24 are respectively connected one-to-one to the relays set in the plurality of DC powers, and are respectively grounded through a plurality of equal-value resistors set one-to-one; the 1OE and 2OE terminals of the voltage regulator chip U24 are both grounded, the VCC terminal of the voltage regulator chip U24 is connected to the +5V DC power of the voltage regulator circuit, and is grounded through the capacitor C55, and the GND terminal of the voltage regulator chip U24 is grounded. The voltage regulator chip U24 is used to convert the drive signal output by the microcontroller U41 into a voltage signal that the relay can recognize. For example, the drive signal of 3.3V output from the P11 terminal of the microcontroller U41 reaches the 1A1 terminal of the voltage regulator chip U24, and then the drive signal of +5V output from the 1Y1 terminal of the voltage regulator chip U24 reaches the relay of the power branch where the mains network (GRID) is located to control the relay to open / close.

[0056] In this embodiment, one of the multiple electrical loads is the mains network and is represented by GRID, one of the multiple electrical loads is the UPS load and is represented by UPS, and the central circuit further includes a multiplexing circuit. The multiplexing circuit includes a multiplexing chip U13, and a chip of the CD4051 model can be specifically used.

[0057] See Figure 4 and Figure 9, the single-chip microcomputer U41 further includes a PE6 terminal and a PE5 terminal, which are used to output multiplexing enable signals respectively; the multiplexing chip U13 includes a 1B1 terminal, a 1B2 terminal, a 1B3 terminal, a 1B4 terminal, a 2B1 terminal, a 2B2 terminal, a 2B3 terminal, a 2B4 terminal, a 1A terminal, a 2A terminal, an S0 terminal, an S1 terminal, an OE terminal, a 2OE terminal, a VCC terminal, and a GND terminal; the 1B1 terminal and the 1B3 terminal of the multiplexing chip U13 are respectively connected to a power line of a power branch where the mains power network is located through equal-value resistors, and the 1B2 terminal and the 1B4 terminal of the multiplexing chip U13 are respectively connected to another power line of the power branch where the mains power network is located through equal-value resistors. The 1B1 terminal, 1B2 terminal, 1B3 terminal, and 1B4 terminal of the multiplexing chip U13 are respectively grounded through capacitors C97, C67, C68, and C73 arranged one-to-one; the 2B1 terminal and the 2B3 terminal of the multiplexing chip U13 are respectively connected to a power line of a power branch where the UPS load is located through equal-value resistors, and the 2B2 terminal and the 2B4 terminal of the multiplexing chip U13 are respectively connected to another power line of the power branch where the UPS load is located through equal-value resistors. The 2B1 terminal, 2B2 terminal, 2B3 terminal, and 2B4 terminal of the multiplexing chip U13 are respectively grounded through capacitors C74, C75, C76, and C77 arranged one-to-one; the 1A terminal and the 2A terminal of the multiplexing chip U13 are respectively connected to the PC3 terminal and the PAO terminal of the single-chip microcomputer U41, the S0 terminal and the S1 terminal of the multiplexing chip are respectively connected to the PE6 terminal and the PE5 terminal of the single-chip microcomputer U41, the OE terminal, the GND terminal, and the 2OE terminal of the multiplexing chip U13 are grounded and connected to the S1 terminal of the multiplexing chip U13 through a capacitor C88, and connected to the S0 terminal of the multiplexing chip U13 through a capacitor C258. The VCC terminal of the multiplexing chip U13 is connected to the +3.3V DC power of the voltage stabilizing circuit and grounded through a capacitor C65.

[0058] It can be understood that the multiplexing chip U13 can select the signal obtained by one of the 1B1 terminal and the 1B2 terminal under the enable of the signal at the S1 terminal and transmit it to the PC3 terminal of the single-chip microcomputer U41 through the 1A terminal. It can also select the signal obtained by one of the 2B1 terminal and the 2B2 terminal under the enable of the signal at the S0 terminal and transmit it to the PAO terminal of the single-chip microcomputer U41 through the 2A terminal. Due to the limitation of the number of I / O pins of the single-chip microcomputer, it is impossible to meet the reading of too many voltage signals and current signals. Therefore, a multiplexing circuit needs to be set to select the input signals of the pins, so as to realize the reading operation of more signals with a smaller number of pins.

[0059] Of course, for the reading of the voltage signals and current signals of the power branches where the mains power network, AC inverter, conventional load, UPS load, standby generator, and energy storage inverter are located respectively, the multiplexing circuit shown in Figure 9 can be selected for use, and no specific description will be given here.

[0060] In this embodiment, referring to Figure 10 , the central circuit further includes a dry contact relay circuit, and the dry contact relay circuit includes an optocoupler U35, a triode Q11, a triode Q8, a triode Q14, and a relay element RY1.

[0061] In Figure 4 and Figure 10 , the single-chip microcomputer U41 further includes a PE1 terminal for outputting a dry contact enable signal; the PE1 terminal of the single-chip microcomputer U41 is connected to the base of the triode Q11 through a resistor R271, the base of the triode Q11 is connected to the collector of the triode Q11 through a resistor R270, the collector of the triode Q11 is connected to one emitter of the optocoupler U35, one emitter of the optocoupler U35 is connected to the other emitter of the optocoupler U35 through a parallel-connected diode D25 and a resistor R269, and the other emitter of the optocoupler U35 is connected to the +3.3V DC power supply of the voltage stabilizing circuit through a resistor R267; one receiving terminal of the optocoupler U35 is connected to the +5V DC power supply of the voltage stabilizing circuit through a resistor R266, the other receiving terminal of the optocoupler U35 is connected to the base of the triode Q8 and grounded through a resistor R272, the emitters of the triode Q8 and the triode Q11 are both grounded, the collector of the triode Q8 is connected to the +5V DC power supply of the voltage stabilizing circuit through a resistor R268 and connected to the base of the triode Q14 through a resistor R276, the base of the triode Q14 is grounded through a resistor R279, the emitter of the triode Q14 is grounded, the collector of the triode Q14 is connected to the control terminal of the relay element RY1, and the control terminal of the relay element RY1 is connected to the +12V DC power supply of the voltage stabilizing circuit through a diode D26; the common contact COM1 and the normally open contact NO1 of the relay element RY1 are used to be connected in series to the power supply line of the microgrid power distribution device.

[0062] It can be understood that the dry contact relay circuit can ensure that when the central circuit detects an abnormal voltage / current in a certain branch, it can quickly cut off the power supply line of the microgrid power distribution device, so that the power supply line of the microgrid power distribution device is in a power-off protection state and avoid damage.

[0063] It should be noted that the central circuit may further include some other circuit mechanisms, such as a parallel operation master-slave competition circuit, a phase synchronization circuit, a state synchronization circuit, a grid-connected and off-grid synchronization circuit, a delay synchronization circuit, etc. These circuits can generate corresponding functions under the enabling action of some ports of the single-chip microcomputer, and even control the collector and the relay to be synchronously triggered. Since they are not the key points of concern in this technical solution, they will not be described in detail here.

[0064] The microgrid power distribution device of the present application can be switched according to the working mode set by the customer. The working mode involved here can adopt the existing technology, such as the control methods disclosed in patent documents (CN109038670A - A Microgrid and Energy Storage System Controller, CN117477755A - Control Method of Microgrid and Power Supply System). Of course, some custom working modes can also be adopted.

[0065] For example, in working mode 1, when the mains power network (GRID) is powered off, the microgrid power distribution device detects no voltage at the port and disconnects the relay on the power branch where the mains power network is located. At the same time, it transmits a signal to the energy storage inverter through the communication line to switch to the off - grid state. At this time, the entire system will enter the off - grid operation mode. Only when the mains power network (GRID) is re - closed and connected to the grid, the relay will be turned on, and the energy storage inverter will be notified to switch to the grid - connected state.

[0066] For example, in working mode 2, when the microgrid power distribution device is operating in the off - grid state, it can let the energy storage inverter maintain the stability of the AC voltage and frequency on the busbar through charge and discharge, and let the ordinary grid - connected inverter or micro - inverter connected to the AC inverter continue to work, and together with the energy storage inverter, form an off - grid system.

[0067] For example, in working mode 3, when the mains power network (GRID) is powered off and the battery connected to the energy storage inverter has a low charge and cannot discharge, the microgrid power distribution device will start the backup generator through a dry contact, and at the same time, close the relay on the power branch where the standby generator is located, and enter the generator power supply mode. When the grid is restored, it will disconnect the standby generator again and close the relay on the power branch where the mains power network is located, and enter the grid - connected state.

[0068] For example, in working mode 4, when some ordinary loads need to be started at specific times or under certain specific working conditions, the user can custom - set the relay on the power branch where the ordinary load is located to be closed under certain specific working conditions, so as to supply power to the ordinary load connected to this power branch. For example, if it is desired that the water heater corresponding to ordinary load 1 works from 5 to 9 o'clock every day, the relay on the corresponding power branch can be set to be closed from 5 to 9 o'clock every day and disconnected at other times.

[0069] The microgrid power distribution device of the present application integrates all electrical loads and power supply units, making it more convenient for customers to install and greatly saving wire materials. This advantage is even more obvious when multiple units are paralleled. At the same time, it has an active switching mode and load control ability, making the entire power distribution more intelligent and capable of maintaining power supply under all working conditions. In addition, the microgrid power distribution device samples current / voltage at each power branch, which can accurately monitor the power flow and distribution of the entire system. Moreover, the microgrid power distribution device also has multiple communication capabilities and can be directly connected to computers and mobile phones, making the monitoring and control of the entire system more convenient.

[0070] It should be noted that the above-mentioned custom working modes 1 to 4 are to help technicians understand the intelligent power distribution ability of the microgrid power distribution device, rather than a limitation on the power distribution control method. The focus of the application lies in the device structure and circuit structure, rather than the working mode. Moreover, the switching and definition of the adopted working mode are considered to be existing technical solutions.

[0071] The above content is a further detailed description of the present application in combination with specific implementation manners. It cannot be determined that the specific implementation of the present application is only limited to these descriptions. For those of ordinary skill in the technical field to which the present application belongs, without departing from the inventive concept of the present application, several simple deductions or substitutions can still be made.

Claims

1. A microgrid power distribution device, characterized in that, Comprising: A busbar for collecting and transmitting electric energy; A plurality of power branches, all connected to the busbar, for respectively connecting to a plurality of power loads; A collector and a relay are arranged on each of the power branches. The collector is used for collecting the electric energy information of the corresponding power branch, and the relay is used for connecting or disconnecting the corresponding power branch; A central circuit is signal-connected to the collectors and relays arranged on each power branch, and is used for obtaining the electric energy signals of the corresponding power branches from the collectors and sending drive signals to the relays.

2. The microgrid power distribution device according to claim 1, characterized in that, The plurality of power loads include multiple ones of a mains power network, an AC inverter, a conventional load, a UPS load, a standby generator, and an energy storage inverter; wherein, the energy storage inverter is used for electrically connecting to a photovoltaic module and / or a battery; A circuit breaker is further arranged on each of the power branches, and the circuit breaker is used for fusing the corresponding power branch in case of overload or short circuit.

3. The microgrid power distribution device according to claim 1, characterized in that, The central circuit includes a DC power supply circuit, and the DC power supply circuit includes a rectifier and a voltage stabilizing circuit. The rectifier is used for obtaining AC electric energy from the busbar and rectifying it into DC electric energy, and the voltage stabilizing circuit is used for obtaining DC electric energy from the rectifier and converting it into DC electric energy of multiple levels. The voltage stabilizing circuit includes a voltage stabilizing chip U1, a voltage stabilizing chip U39, an operational amplifier U25A, and an operational amplifier U25D; The voltage stabilizing chip U1 has a BOOT terminal, a VIN terminal, an EN terminal, an SS terminal, a VSENSE terminal, a COMP terminal, a GND terminal, and a PH terminal. Among them, the VIN terminal of the voltage stabilizing chip U1 is connected to the rectifier and obtains +12V DC electric energy, and is respectively grounded through the capacitors C768, C764, and C9 connected in parallel, and grounded through the resistors R1015 and R1022 connected in series. The connection terminal of the resistors R1015 and R1022 is connected to the EN terminal of the voltage stabilizing chip U1. The SS terminal of the voltage stabilizing chip U1 is grounded through the capacitor C763. The BOOT terminal of the voltage stabilizing chip U1 is grounded through the capacitor C752, the inductor L17, the resistor R1013, the resistor R1020, and the resistor R1024 arranged in series. The connection terminal of the capacitor C752 and the inductor L17 is connected to the PH terminal of the voltage stabilizing chip U1 and is connected to the GND terminal of the voltage stabilizing chip U1 through the diode D127. The connection terminal of the inductor L17 and the resistor R1013 is connected to the GND terminal of the voltage stabilizing chip U1 through the capacitors C756, C755, and C753 connected in parallel. The connection terminal of the resistor R1013 and the resistor R1020 is connected to the VSENSSE terminal of the voltage stabilizing chip U1. The COMP terminal of the voltage stabilizing chip U1 is grounded through the resistor R1017 and the capacitor C767 connected in series, and grounded through the capacitor C765; The connection terminal of the inductor L17 and the resistor R1013 is used to generate +5V DC electric energy of the voltage stabilizing circuit; The voltage regulator chip U39 includes a Vin terminal, a Vout terminal, and a GND terminal. Among them, the Vin terminal of the voltage regulator chip U39 obtains the +5V DC power of the voltage regulation circuit, and is grounded through the capacitors C268, C269, and C7 connected in parallel. The Vout terminal of the voltage regulator chip U39 is grounded through the capacitors C272, C271, C140, C167, and C270 connected in parallel, and is grounded through the LED1 and resistor R5 connected in series. The GND terminal of the voltage regulator chip U39 is directly grounded; the Vout terminal of the voltage regulator chip U39 is used to generate the +3.3V DC power of the voltage regulation circuit; The non-inverting input terminal of the operational amplifier U25A obtains the +5V DC power of the voltage regulation circuit through the resistors R167 and R158 connected in series. The connection terminal of the resistors R158 and R167 is grounded through the resistors R166 and R174 connected in series, and is grounded through the diode U16 and capacitor C174 connected in parallel. The other end of the resistor R158 is grounded through the capacitors C111 and C109 connected in parallel. The inverting input terminal of the operational amplifier U25A is grounded through the diode ZD18, capacitors C160, C340, C162, and C341 connected in parallel, and the inverting input terminal of the operational amplifier U25A is connected to the output terminal of the operational amplifier U25A through the resistor R164; The non-inverting input terminal of the operational amplifier U25D is connected to the connection terminal of the resistor R158 and the resistor R168 through the capacitor R326. The inverting input terminal of the operational amplifier U25D is grounded through the capacitors C344, C107, C342, and C343 connected in parallel, and the inverting input terminal of the operational amplifier U25D is connected to the output terminal of the operational amplifier U25D through the resistor R175; The inverting input terminal of the operational amplifier U25A is used to generate the +3VAP DC power of the voltage regulation circuit, and the inverting input terminal of the operational amplifier U25D is used to generate the +3VB DC power of the voltage regulation circuit.

4. The microgrid power distribution device according to claim 3, characterized in that, The central circuit further includes a single-chip microcomputer U41, and the single-chip microcomputer U41 includes a PC14 terminal, a PC15 terminal, an OSC-IN terminal, an OSC-OUT terminal, a VSS terminal, and a VDD terminal; A crystal oscillator XL4 is connected between the PC14 terminal and the PC15 terminal of the single-chip microcomputer U41, and the crystal oscillator XL4 is connected in parallel with the resistors C259 and C262 connected in sequence, and the connection terminal of the resistors C259 and C262 is grounded; A crystal oscillator XL1 is connected between the OSC-IN terminal and the OSC-OUT terminal of the single-chip microcomputer U41, and the crystal oscillator XL1 is connected in parallel with the resistors C285 and C287 connected in sequence, and the connection terminal of the resistors C285 and C287 is grounded; The VSS terminal of the single-chip microcomputer U41 is grounded, and the VDD terminal of the single-chip microcomputer U41 obtains the +3.3V DC power from the voltage regulation circuit; The single-chip microcomputer U41 also includes PC0, PC1, PC2, PC3, PA0, and PA1, which are used to obtain the power signals of the multiple power branches regarding voltage respectively; The single-chip microcomputer U41 also includes PA2, PA3, PA4, PA5, PA6, PA7, PC4, PC5, PB0, and PB1, which are used to obtain the power signals of the multiple power branches regarding current respectively; The single-chip microcomputer U41 also includes PE7, PE8, PE9, PE10, PE11, PE13, PE14, and PE15, which are used to send drive signals to the relays in the multiple power branches respectively.

5. The microgrid power distribution device according to claim 4, characterized in that, One of the multiple power loads is the mains network, denoted by GRID, and the collector on the power branch connected to the mains network includes a mains voltage acquisition circuit and a mains current acquisition circuit; The mains voltage acquisition circuit includes operational amplifiers U4C and U8B; the non-inverting terminal of operational amplifier U4C is connected to one power line of the power branch where the mains network is located through resistor R17, and is grounded through the parallel-connected capacitor C335 and resistor R21. The inverting terminal of operational amplifier U4C is connected to the other power line of the power branch where the mains network is located through resistor R14, and is connected to the output terminal of operational amplifier U4C through the parallel-connected capacitor C332 and resistor R1099. The output terminal of operational amplifier U4C is connected to the non-inverting terminal of operational amplifier U8B through resistor R1102. The non-inverting terminal of operational amplifier U8B is connected to the +3VB DC power supply of the voltage stabilizing circuit through the parallel-connected capacitor C27 and resistor R36, and is grounded through capacitor C98. The inverting terminal of operational amplifier U8B is connected to the output terminal of operational amplifier U8B. The output terminal of operational amplifier U8B is grounded through the series-connected resistor R79 and capacitor C70. The connection terminal of resistor R79 and capacitor C70 is connected to the PC0 terminal of the single-chip microcomputer U41, and the PC0 terminal of the single-chip microcomputer U41 is configured to obtain the voltage of the power branch where the mains network is located; The mains current acquisition circuit includes operational amplifiers U5D, U6D, and U17B. The non-inverting input terminal of operational amplifier U5D is connected to one side of a power line of the power branch where the mains network is located through resistor R91, and is grounded through the parallel-connected capacitor C36 and resistor R115. The inverting input terminal of operational amplifier U5D is connected to the other side of the same power line of the power branch where the mains network is located through resistor R82, and is connected to the output terminal of operational amplifier U5D through the parallel-connected capacitor C31 and resistor R71. The output terminal of operational amplifier U5D is connected to the non-inverting input terminal of operational amplifier U17B through resistor R49, and one end of resistor R49 is connected to the +3VB DC power supply of the voltage stabilizing circuit through the series-connected capacitor C149 and resistor R57. The non-inverting input terminal of operational amplifier U6D is connected to one side of another power line of the power branch where the mains network is located through resistor R89, and is grounded through the parallel-connected capacitor C37 and resistor R113. The inverting input terminal of operational amplifier U6D is connected to the other side of the same power line of the power branch where the mains network is located through resistor R83, and is connected to the output terminal of operational amplifier U6D through the parallel-connected capacitor C29 and resistor R193. The output terminal of operational amplifier U6D is connected to the non-inverting input terminal of operational amplifier U17B through resistor R47, and one end of resistor R47 is connected to the +3VB DC power supply of the voltage stabilizing circuit through the series-connected resistor R195 and capacitor C146. The non-inverting input terminal of operational amplifier U17B is grounded through capacitor C143. The inverting input terminal of operational amplifier U17B is connected to the output terminal of operational amplifier U17B. The output terminal of operational amplifier U17B is grounded through the series-connected resistor R3 and capacitor C4. The connection terminal of resistor R3 and capacitor C4 is connected to the PA2 terminal of microcontroller U41. The PA2 terminal of microcontroller U41 is configured to acquire the current of the power branch where the mains network is located.

6. The microgrid power distribution device according to claim 4, characterized in that, The central circuit further includes a zero-crossing detection circuit for the voltage of the power branch where the mains network is located. The zero-crossing detection circuit for voltage includes operational amplifier U27C. The inverting input terminal of operational amplifier U27C is connected to the non-inverting input terminal of operational amplifier U8B in the mains voltage acquisition circuit through resistor R163, and is grounded through capacitor C53. The non-inverting input terminal of operational amplifier U27C is connected to the +3VAP DC power supply of the voltage stabilizing circuit through resistor R188, and is grounded through the parallel-connected capacitor C56 and resistor R97, and is connected to the output terminal of operational amplifier U27C through resistor R61. The output terminal of operational amplifier U27C is connected to the +3.3V DC power supply of the voltage stabilizing circuit through resistor R52, and is grounded through the series-connected resistor R55 and capacitor C51. Microcontroller U41 further includes a PB10 terminal. The PB10 terminal of microcontroller U41 is connected to the connection terminal of resistor R55 and capacitor C51, and is configured to acquire the zero-crossing signal of the voltage of the power branch where the mains network is located.

7. The microgrid power distribution device according to claim 4, characterized in that The central circuit further includes a relay drive circuit, and the relay drive circuit includes a voltage regulator chip U24; The voltage regulator chip U24 includes 1A1 terminal, 1A2 terminal, 1A3 terminal, 1A4 terminal, 2A1 terminal, 2A2 terminal, 2A3 terminal, 2A4 terminal, 1Y1 terminal, 1Y2 terminal, 1Y3 terminal, 1Y4 terminal, 2Y1 terminal, 2Y2 terminal, 2Y3 terminal, 2Y4 terminal, VCC terminal, GND terminal, 1OE terminal, and 2OE terminal; The 1A1 terminal, 1A2 terminal, 1A3 terminal, 1A4 terminal, 2A1 terminal, 2A2 terminal, 2A3 terminal, and 2A4 terminal of the voltage regulator chip U24 are respectively grounded through capacitors C161, C108, C106, C92, C91, C60, C58, and C57 arranged one-to-one, and are respectively connected to the PE11 terminal, PE13 terminal, E14 terminal, PE15 terminal, PE7 terminal, PE8 terminal, PE9 terminal, and PE10 terminal of the microcontroller U41 through resistors R11, R23, R31, R41, R43, R45, R59, and R62 arranged one-to-one. The PE11 terminal, PE13 terminal, E14 terminal, PE15 terminal, PE7 terminal, PE8 terminal, PE9 terminal, and PE10 terminal of the microcontroller U41 are respectively grounded through multiple equal-value resistors arranged one-to-one; the 1Y1 terminal, 1Y2 terminal, 1Y3 terminal, 1Y4 terminal, 2Y1 terminal, 2Y2 terminal, 2Y3 terminal, and 2Y4 terminal of the voltage regulator chip U24 are respectively connected to the relays arranged in the multiple DC powers one-to-one, and are respectively grounded through multiple equal-value resistors arranged one-to-one; the 1OE terminal and 2OE terminal of the voltage regulator chip U24 are both grounded, the VCC terminal of the voltage regulator chip U24 is connected to the +5V DC power of the voltage regulator circuit and is grounded through capacitor C55, and the GND terminal of the voltage regulator chip U24 is grounded; The voltage regulator chip U24 is used to convert the drive signal output by the microcontroller U41 into a voltage signal recognizable by the relay.

8. The microgrid power distribution device according to claim 4, characterized in that, One of the multiple electrical loads is a mains network represented by GRID, and one of the multiple electrical loads is a UPS load represented by UPS. The central circuit further includes a multiplexing circuit, and the multiplexing circuit includes a multiplexing chip U13; The microcontroller U41 further includes a PE6 terminal and a PE5 terminal for respectively outputting multiplexing enable signals; The multiplexing chip U13 includes terminals 1B1, 1B2, 1B3, 1B4, 2B1, 2B2, 2B3, 2B4, 1A, 2A, S0, S1, OE, 2OE, VCC, and GND. The 1B1 and 1B3 terminals of the multiplexing chip U13 are respectively connected to a power line of the power branch where the mains power network is located through equivalent resistors. The 1B2 and 1B4 terminals of the multiplexing chip U13 are respectively connected to another power line of the power branch where the mains power network is located through equivalent resistors. The 1B1, 1B2, 1B3, and 1B4 terminals of the multiplexing chip U13 are respectively grounded through capacitors C97, C67, C68, and C73 arranged one-to-one. The 2B1 and 2B3 terminals of the multiplexing chip U13 are respectively connected to a power line of the power branch where the UPS load is located through equivalent resistors. The 2B2 and 2B4 terminals of the multiplexing chip U13 are respectively connected to another power line of the power branch where the UPS load is located through equivalent resistors. The 2B1, 2B2, 2B3, and 2B4 terminals of the multiplexing chip U13 are respectively grounded through capacitors C74, C75, C76, and C77 arranged one-to-one. The 1A and 2A terminals of the multiplexing chip U13 are respectively connected to the PC3 terminal and PA0 terminal of the microcontroller U41. The S0 and S1 terminals of the multiplexing chip are respectively connected to the PE6 terminal and PE5 terminal of the microcontroller U41. The OE, GND, and 2OE terminals of the multiplexing chip U13 are grounded and connected to the S1 terminal of the multiplexing chip U13 through capacitor C88, and connected to the S0 terminal of the multiplexing chip U13 through capacitor C258. The VCC terminal of the multiplexing chip U13 is connected to the +3.3V DC power of the voltage stabilizing circuit and grounded through capacitor C65. The multiplexing chip U13 can select the signal obtained from one of the 1B1 and 1B2 terminals under the enabling of the signal at the S1 terminal and transmit it to the PC3 terminal of the microcontroller U41 through the 1A terminal. It can also select the signal obtained from one of the 2B1 and 2B2 terminals under the enabling of the signal at the S0 terminal and transmit it to the PA0 terminal of the microcontroller U41 through the 2A terminal.

9. The microgrid power distribution device according to claim 4, characterized in that, The central circuit further includes a dry contact relay circuit, and the dry contact relay circuit includes optocoupler U35, triode Q11, triode Q8, triode Q14, and relay element RY1. The single-chip microcomputer U41 also includes a PE1 terminal for outputting a dry contact enable signal; the PE1 terminal of the single-chip microcomputer U41 is connected to the base of the triode Q11 through the resistor R271, the base of the triode Q11 is connected to the collector of the triode Q11 through the resistor R270, and the collector of the triode Q11 is connected to an emitter of the optocoupler U35. An emitter of the optocoupler U35 is connected to the other emitter of the optocoupler U35 through the diode D25 and the resistor R269 connected in parallel. The other emitter of the optocoupler U35 is connected to the +3.3V DC power supply of the voltage stabilizing circuit through the resistor R267. A receiving terminal of the optocoupler U35 is connected to the +5V DC power supply of the voltage stabilizing circuit through the resistor R266. The other receiving terminal of the optocoupler U35 is connected to the base of the triode Q8 and grounded through the resistor R272. The emitters of the triode Q8 and the triode Q11 are both grounded. The collector of the triode Q8 is connected to the +5V DC power supply of the voltage stabilizing circuit through the resistor R268 and connected to the base of the triode Q14 through the resistor R276. The base of the triode Q14 is grounded through the resistor R279. The emitter of the triode Q14 is grounded. The collector of the triode Q14 is connected to the control terminal of the relay element RY1. The control terminal of the relay element RY1 is connected to the +12V DC power supply of the voltage stabilizing circuit through the diode D26. The common contact COM1 and the normally open contact NO1 of the relay element RY1 are used to be connected in series to the power supply line of the microgrid power distribution device.

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