Energy-saving centralized direct-current power supply method and device for electrical appliances

Abstract

The present invention discloses an energy-saving centralized direct-current (DC) power supply method and device for electrical appliances. In order to solve the problem of high energy consumption of distributed inversion for DC loads in shops and shopping malls, in the present invention, a central inversion power supply method is used, a third-generation SiC mosfet is used as an inversion core, a PFC is used to perform power factor correction on a power supply end, and a CLLLC achieves lossless on-off of switch transistors, providing a new way for energy-saving power supply. A human-machine interface (HMI) is used for setting and detecting the operation status and output parameters of the system. A main controller issues an output command to a main circuit controller and collects current and voltage signals to detect the operation statuses of modules. Three-phase power from a power grid is supplied to the PFC module to achieve power factor correction, and the voltage is adjusted to 700 V DC to supply power to a DC-DC inverter. The power is diverted by means of a shunt and output to loads such as lamp beads, air conditioners and other devices to provide DC, thus achieving distribution to electrical appliances in shops or shopping malls.

Description

Energy-saving centralized DC power supply method and device for electrical appliances Technical Field

[0001] The present invention belongs to the technical field of energy-saving electrical appliances, and in particular relates to a centralized direct current power supply method and equipment for energy-saving electrical appliances. Background Art

[0002] With technological advancements, DC power equipment, such as LED lights and built-in cooling systems in air conditioners, has become widely used in shopping malls and stores. However, currently, LEDs and DC power equipment on the market all use separate inverters. Each module in a separate inverter generates power loss, primarily as heat. The amount of power loss varies depending on the manufacturer of the separate inverter circuit. Effectively improving and enhancing the power dissipation caused by separate multi-channel inverters has become a key technological innovation. However, there are currently no devices or methods that effectively address the high switching losses and persistently high energy consumption of distributed inverter modules.

[0003] Summary of the Invention

[0004] To address the shortcomings of the existing technology, the present invention proposes an energy-saving centralized DC power supply method and equipment for electrical appliances. The method adopts the third-generation SiC MOSFET as the inverter core, replacing conventional high-energy-consuming switching devices such as transistors and MOSFETs. PFC performs power factor correction on the power supply end, and CLLLC achieves lossless switching of the switching tube, effectively solving the problems of large switching losses and high energy consumption in distributed inverter modules, and providing a new approach to energy-saving power supply.

[0005] The present invention utilizes the following technical solutions.

[0006] An energy-saving centralized DC power supply device for electrical appliances, comprising:

[0007] HMI, main controller, three-phase PFC, DC-DC inverter, shunt, DC load, current detection circuit and voltage detection circuit 1, and current detection circuit and voltage detection circuit 2;

[0008] The HMI, the shunt, the current detection circuit and the voltage detection circuit 1, as well as the current detection circuit and the voltage detection circuit 2 are all connected to the main controller;

[0009] The current detection circuit and the voltage detection circuit 1 are connected to the three-phase PFC, and the current detection circuit and the voltage detection circuit 1 are used to collect the current and voltage of the three-phase PFC;

[0010] The current detection circuit and the second voltage detection circuit are connected to the DC-DC inverter device, and the current detection circuit and the second voltage detection circuit are used to collect the current and voltage of the DC-DC inverter device;

[0011] The three-phase PFC, the DC-DC inverter, the splitter and the DC load are connected in sequence.

[0012] Preferably, the HMI is used to set and detect the operating status and output parameters of the energy-saving electrical appliance centralized DC power supply device, issue output commands to the main controller, and simultaneously collect current and voltage signals of the three-phase PFC and DC-DC inverter device through the current detection circuit and voltage detection circuit 1 and the current detection circuit and voltage detection circuit 2 respectively to detect the operating status of the three-phase PFC and DC-DC inverter device;

[0013] The three-phase power from the grid is supplied to the three-phase PFC, which uses its Vienna bridge to achieve power factor correction and regulates the voltage to 700V DC to power the DC-DC inverter. The DC is then diverted through a splitter and output to the DC load to provide DC.

[0014] Preferably, the three-phase PFC includes:

[0015] The SiC uncontrolled rectifier bridge is composed of diodes D1-D6, the MOS tubes Q1-Q6 form a Vienna bridge, the MOS tubes Q7-Q10 form a full-bridge inverter topology, the L1-L3 filter inductors are connected to the full-bridge inverter topology, and the diodes D7-D12 connected to the full-bridge inverter topology are SiC MOSFET reverse freewheeling diodes.

[0016] Preferably, the DC-DC inverter device includes:

[0017] D13-D16 rectifier diodes, L4, L5 resonant inductors, transformer T1, C1-C7 filter inductors and 500kHz high-frequency transformer.

[0018] Preferably, the voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 2 and the voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 1 is the same, and the voltage acquisition circuit includes:

[0019] Resistors R8-R12 divide the voltage and output it to R13 and R14 through linear optocoupler U2Pin6 and Pin7. Capacitor C17 filters and connects to U3. U3 is an operational amplifier. After amplification, the output is sent to the FDBK acquisition terminal. R18 and C21 are filtering circuits. FDBK is connected to the ADC acquisition pin of the main controller.

[0020] Preferably, the current detection circuit and the voltage detection circuit 2 and the voltage detection circuit and the voltage detection circuit 1 have the same voltage acquisition circuit structure, and the current acquisition circuit includes:

[0021] Resistor R19, capacitor C22 and capacitor C23 form a current limiting and voltage stabilizing circuit. The current sensor to IL_N, IL_P is input to the U4 operational amplifier. After being amplified by the amplifier circuit composed of U4, resistor R20 and resistor R21, the signal is output to resistor R4, filtered by capacitor C3, and transmitted to IL_Fdbk. IL_Fdbk is connected to the ADC acquisition end of the main controller.

[0022] A method for centralized DC power supply for energy-saving electrical appliances, comprising:

[0023] Step 1: Perform status checks such as PFC status check, CLLLC status check, and splitter status check;

[0024] Step 2: If a fault occurs during the status detection process, the operation of modules such as the three-phase PFC, DC-DC inverter, and splitter will be stopped. The HMI will pop up a fault alarm and fault code, and the main controller will terminate the subsequent steps.

[0025] Step 3: If the status detection result is normal, the output parameter setting is performed by the corresponding algorithm module to calculate the parameter value required for output.

[0026] Preferably, the method for centralized DC power supply for energy-saving electrical appliances further includes:

[0027] During the operation of modules such as three-phase PFC, DC-DC inverter and splitter, the temperature sensor collects the temperature of the module in real time and transmits it to the main controller for detection.

[0028] Preferably, the method for detecting the PFC state includes:

[0029] The voltage acquisition circuit and the current acquisition circuit respectively collect the voltage and current values ​​of the set detection points Collect1-Collect5, and calculate the average value of the three-phase input voltage, VMeas = (((float32_t)(V_FB_1+VIENNA_V_FB_2+V_FB_3+V3_FB_4))×ADC_CALE_FACTOR×0.25-v3MeasOffset)×2.0; with the average value as the target, calculate the error value: Voltage_error_buffer = fabs(VBusRefSlewed_buffer–VbusMeas_buffer); adjust the PWM duty cycle according to the error value to maintain three-phase voltage balance. The current loop balancing process is similar.

[0030] Preferably, the method for detecting the CLLLC state includes:

[0031] The voltage and current acquisition circuits respectively collect the voltage and current at the set Collect6-Collect9 acquisition points, and collect the current and voltage values ​​of the primary and secondary sides of the transformer. By adjusting the switching frequency of the upper and lower bridge arms, they resonate with the primary side capacitor C4, inductor L1, and capacitor C5, making them operate in a soft switching state. The switching frequency is adjusted to adjust the output voltage.

[0032] The method of branch detection includes: detecting the current value of each load separately, and judging whether the load is operating normally according to the collected circuit value.

[0033] Preferably, the method for centralized DC power supply for energy-saving electrical appliances further includes:

[0034] The HMI control interface displays the voltage and current of three phases A, B, and C, and calculates the active power and power factor of each phase to detect the operating status of the system in real time.

[0035] Preferably, the method for performing calculations by the corresponding algorithm module includes:

[0036] The present invention constructs a fuzzy neural network PID controller running on a main controller to realize multi-channel output balance control, takes the error e and the error change rate ec as the input of the fuzzy neural network, and the correction values ​​ΔKP, ΔKI, and ΔKD of the PID parameters as outputs. By controlling the correction values, online adjustment of the three PID parameters is realized.

[0037] Preferably, the fuzzy neural network adopts a two-input and three-output network structure model, which specifically includes:

[0038] By detecting the output current and voltage values ​​of each shunt, the power of each channel can be calculated. The actual power of the entire system is the sum of the actual power and the rated power. The difference between the actual power and the rated power is e, and the difference change is ec. E and ec are input as the input layer:

[0039] enter:

[0040] The output of the input layer is: Q1(i,j)=I1(i)(i=1,2,j=1,2,...,7)

[0041] The input and output of the fuzzification layer are:

[0042] enter:

[0043] Output: O2(i,j)=exp(I2(i,j))(i=1,2,j=1,2,...,7)

[0044] Where cij is the center value of the membership function, and bij is the width of the membership function.

[0045] The input and output of the fuzzy inference layer are:

[0046] Input: P3(i)=O2(1,j1)O2(2,j2)(i=1,2,...,49,j1,j2=1,2,...,7)

[0047] Output: Q3(i)=I3(i)(i=1,2,...,49)

[0048] The input and output of the output layer are:

[0049] enter:

[0050] Output: Q4(j)=I4(j)(j=1,2,3)

[0051] Where wij is the weight coefficient from the fuzzy inference layer to the output layer, and the output is the correction value of the PID parameter:

[0052] The output of the fuzzy neural network is the corrected value of the three PID parameters:

[0053] The output of the fuzzy neural network PID controller is: u(k)=K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]+u(k-1)

[0054] Where u(k) is the output of the system at time kT; e(k) is the system error at time kT.

[0055] The beneficial effect of the present invention is that, compared with the prior art, the present invention solves the problem of high energy consumption of distributed inverters for DC loads in shops and shopping malls. The present invention adopts a centralized inverter power supply method, adopts the third-generation SiC MOSFET as the inverter core, uses PFC to perform power factor correction on the power supply end, and CLLLC realizes lossless on-off of the switch tube, providing a new way to energy-saving power supply. The human-machine interface (HMI) is used to set and detect the operating status and output parameters of the system. The output command is issued to the main circuit controller through the main controller, and the current and voltage signals are collected at the same time to detect the operating status of each module. The three-phase power of the power grid is supplied to the PFC module to realize power factor correction, and the voltage is adjusted to 700V DC to power the DC-DC inverter. The output is diverted by the shunt and output to loads such as lamp beads, air conditioners and other equipment to provide DC, which is distributed to electrical appliances in shops or shopping malls. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] FIG1 is a schematic diagram of an energy-saving centralized DC power supply device for electrical appliances according to the present invention;

[0057] FIG2 is a circuit diagram of the three-phase PFC and DC-DC inverter device of the present invention;

[0058] FIG3 is a circuit diagram of the voltage acquisition circuit of the present invention;

[0059] FIG4 is a circuit diagram of the current acquisition circuit of the present invention;

[0060] FIG5 is a flow chart of the software control in the present invention;

[0061] FIG6 is a schematic diagram of the control interface of the HMI of the present invention;

[0062] FIG7 is a structural diagram of the fuzzy neural network PID controller according to the present invention;

[0063] FIG8 is a structural diagram of the fuzzy neural network described in the present invention. DETAILED DESCRIPTION

[0064] To reduce energy consumption, the present invention proposes an energy-saving centralized LED power supply method. The method adopts the third-generation SiC MOSFET as the inverter core, replacing conventional high-energy-consuming switching devices such as transistors and MOSFETs. PFC performs power factor correction on the power supply end, and CLLLC realizes lossless switching of the switching tube, effectively solving the problems of large switching losses and high energy consumption in distributed inverter modules, and providing a new approach to energy-saving power supply.

[0065] To make the purpose, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely expressed below in conjunction with the drawings in the embodiments of the present invention. The embodiments expressed in this application are only part of the embodiments of the present invention, not all of them. Based on the spirit of the present invention, other embodiments obtained by ordinary technicians in this field without making creative work are all within the scope of protection of the present invention.

[0066] As shown in FIG1 , the interactive service platform for diversified energy supply and utilization equipment of the present invention includes:

[0067] HMI, main controller, three-phase PFC, DC-DC inverter, shunt, DC load, current detection circuit and voltage detection circuit 1, and current detection circuit and voltage detection circuit 2;

[0068] The HMI, the shunt, the current detection circuit and the voltage detection circuit 1, as well as the current detection circuit and the voltage detection circuit 2 are all connected to the main controller;

[0069] The current detection circuit and the voltage detection circuit 1 are connected to the three-phase PFC, and the current detection circuit and the voltage detection circuit 1 are used to collect the current and voltage of the three-phase PFC;

[0070] The current detection circuit and the second voltage detection circuit are connected to the DC-DC inverter device, and the current detection circuit and the second voltage detection circuit are used to collect the current and voltage of the DC-DC inverter device;

[0071] The three-phase PFC, the DC-DC inverter, the splitter and the DC load are connected in sequence.

[0072] In a preferred but non-limiting embodiment of the present invention, a human-machine interface (HMI) is used to set and detect the operating status and output parameters of the energy-saving centralized DC power supply device for electrical appliances, issue output commands to the main controller, and simultaneously collect current and voltage signals of the three-phase PFC and DC-DC inverter device through the current detection circuit and voltage detection circuit 1 and the current detection circuit and voltage detection circuit 2, respectively, to detect the operating status of the three-phase PFC and DC-DC inverter device;

[0073] The three-phase grid power is fed to a three-phase PFC, which uses its Vienna bridge to perform power factor correction. The voltage is then regulated to 700VDC to power the DC-DC inverter. This power is then diverted through a splitter and output to DC loads such as lamps and air conditioners, providing DC power for distribution to electrical appliances in stores or shopping malls. The use of SiC MOSFETs reduces energy loss during centralized inverter operation, replacing distributed, individual inverters and achieving energy savings. A centralized power supply module with a power output of 10kW can achieve centralized inverter operation in a local area.

[0074] In a preferred but non-limiting embodiment of the present invention, as shown in FIG2 , a three-phase PFC includes:

[0075] The SiC uncontrolled rectifier bridge is composed of diodes D1-D6, the MOS tubes Q1-Q6 form a Vienna bridge, the MOS tubes Q7-Q10 form a full-bridge inverter topology, the L1-L3 filter inductors are connected to the full-bridge inverter topology, and the diodes D7-D12 connected to the full-bridge inverter topology are SiC MOSFET reverse freewheeling diodes.

[0076] In a preferred but non-limiting embodiment of the present invention, the DC-DC inverter device includes:

[0077] Rectifier diodes D13-D16, resonant inductors L4 and L5, transformer T1, filter inductors C1-C7, and a 500kHz high-frequency transformer are included. The three-phase power is filtered by L1-L3 and input into an uncontrolled rectifier circuit consisting of SiC MOSFETs D1-D6. DC is then filtered by capacitors C1 and C2. Load changes adjust the PWM pulse widths of the three switching transistor pairs Q1, Q2; Q3, Q4; and Q5, Q6, respectively, to adjust the three-phase AC waveform. This stabilizes the input voltage and maintains three-phase voltage balance despite subsequent load changes or power fluctuations. The full-bridge circuit adjusts the frequency of the transistor pairs Q7, Q10; Q8, Q9 to create resonance in inductors L4, L5, capacitors C1, C2, and transformer T1, reducing energy loss during switching and achieving the desired DC output voltage.

[0078] As shown in FIG3 , in a preferred but non-limiting embodiment of the present invention, the voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 2 and the voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 1 are the same, and the voltage acquisition circuit includes:

[0079] Resistors R8-R12 divide the voltage, which is then output to R13 and R14 via a linear optocoupler (U2) at Pins 6 and 7. Capacitor C17 filters the voltage and connects it to U3, an operational amplifier. After amplification, the output is sent to the FDBK data acquisition terminal. R18 and C21 form a filtering circuit. FDBK is connected to the main controller's ADC data acquisition pin. In Figure 2, the Collect1-Collect9 detection points measure voltage values, respectively, for current collection in the PFC and CLLC circuits. The collected current is then fed into the CPU software for circuit protection, pulse width modulation, and algorithm adjustments.

[0080] As shown in FIG4 , in a preferred but non-limiting embodiment of the present invention, the current detection circuit and the voltage detection circuit 2 and the voltage detection circuit 1 have the same voltage acquisition circuit structure, and the current acquisition circuit includes:

[0081] Resistor R19, capacitors C22, and C23 form a current-limiting and voltage-stabilizing circuit. The current sensor, IL_N and IL_P, feeds into the U4 operational amplifier. After amplification by the amplifier circuit consisting of U4, resistors R20, and R21, the signal is output to resistor R4, filtered by capacitor C3, and transmitted to IL_Fdbk, which is connected to the main controller's ADC. In Figure 2, points Collect1 through Collect9 measure current values ​​for the PFC and CLLC circuits, respectively. The collected current is then fed into the software for circuit protection, pulse width modulation, and algorithm adjustments.

[0082] As shown in FIG5 , the energy-saving centralized DC power supply method for electrical appliances according to the present invention includes:

[0083] Step 1: Perform PFC status detection, CLLLC status detection and splitter detection status detection; detect the current value of each load (Load 1, Load 2, Load N) respectively, and determine whether the load is operating normally based on the collected circuit value.

[0084] Step 2: If a fault occurs during the status detection process, modules such as the three-phase PFC, DC-DC inverter, and shunt are stopped. A fault alarm and fault code are displayed on the HMI, and the main controller terminates subsequent steps. The system then checks for PFC faults such as overvoltage, overcurrent, or three-phase imbalance; DC-DC faults such as primary-side overcurrent, primary-side overvoltage, SiC MOSFET overcurrent, secondary-side overcurrent, and secondary-side overvoltage; and single-circuit shorts and overcurrent in the shunt. Protection thresholds are set for each fault, and during the interruption, the system checks whether the equipment is operating within the specified window.

[0085] Step 3: If the status detection result is normal, the output parameter setting is performed by the corresponding algorithm module to calculate the parameter value required for output.

[0086] In a preferred but non-limiting embodiment of the present invention, the energy-saving electrical appliance centralized DC power supply method further includes:

[0087] During the operation of modules such as three-phase PFC, DC-DC inverter and splitter, the temperature sensor collects the temperature of the module in real time and transmits it to the main controller for detection to avoid overheating protection.

[0088] In a preferred but non-limiting embodiment of the present invention, the method for detecting the PFC state includes:

[0089] The hardware consists of the voltage acquisition circuit in Figure 3 and the current acquisition circuit in Figure 4, which respectively collect the voltage and current values ​​of the Collect1-Collect5 detection points set in Figure 2, and calculate the average value of the three-phase input voltage, VMeas = (((float32_t)(V_FB_1+VIENNA_V_FB_2+V_FB_3))×ADC_CALE_FACTOR×0.25-v3MeasOffset)×2.0, where: VMeas is the three-phase average voltage, V_FB_1 is the first phase detection voltage value, VIENNA_V_FB_2 is the second phase detection voltage value, V_FB_3 is the third phase detection value, and ADC_ALE_FACTOR is the analog The conversion coefficient between the simulated acquisition value and the actual current value, v3MeasOffset is the zero offset value of the op amp acquisition value; with the average value as the target, calculate the error value: Voltage_error_buffer = fabs(VBusRefSlewed_buffer – VbusMeas_buffer), where Voltage_error_buffer is the error value between the set value and the actual voltage, VBusRefSlewed_buffer is the set voltage value, and VbusMeas_buffer is the actual average value of the three-phase voltage acquired; adjust the PWM duty cycle according to the error value to maintain the three-phase voltage balance, and the current loop balancing process is similar.

[0090] In a preferred but non-limiting embodiment of the present invention, the method for detecting the CLLLC state includes:

[0091] The hardware consists of the voltage acquisition circuit in Figure 3 and the current acquisition circuit in Figure 4, which respectively collect the voltage and current of the set Collect6-Collect9 acquisition points, and collect the primary and secondary current and voltage values ​​of the transformer. By adjusting the switching frequency of the upper and lower bridge arms, resonance is generated with the primary side capacitor C4, inductor L1, and capacitor C5, making it operate in a soft switching state, and adjusting the switching frequency to achieve output voltage regulation.

[0092] In a preferred but non-limiting embodiment of the present invention, the energy-saving electrical appliance centralized DC power supply method further includes:

[0093] The HMI control interface, shown in Figure 6, displays the voltage and current of three phases A, B, and C. The three-phase voltage acquisition circuit is described in Figure 3, and the three-phase current acquisition circuit is described in Figure 4. The voltage and current values ​​at Colect1, Colect2, and Colect3 (Figure 1) are collected, respectively. The active power and power factor of each phase are calculated to monitor the system's operating status in real time. The output voltage or current can be set to meet the needs of different loads. Constant voltage or constant current operation is available, monitoring the module's output voltage and current. If a module fails, overheats, or overcurrent occurs, the HMI indicator turns red and the device stops operating.

[0094] In a preferred but non-limiting embodiment of the present invention, the method for performing calculations by the corresponding algorithm module includes:

[0095] The present invention implements a fuzzy neural network PID controller running on a master controller to achieve multi-channel output balancing control. The fuzzy neural network PID controller structure is shown in Figure 7. The error e and error change rate ec serve as inputs to the fuzzy neural network, and the PID parameter correction values ​​ΔKP, ΔKI, and ΔKD serve as outputs. By controlling the correction values, the three PID parameters can be adjusted online. Depending on the load power rating, the circuit parameters are adjusted to ensure that the output DC power always matches the load power rating.

[0096] In a preferred but non-limiting embodiment of the present invention, the fuzzy neural network adopts a two-input and three-output network structure model, the structure of which is shown in FIG8 , and specifically includes:

[0097] By detecting the output current and voltage values ​​of each shunt, the power of each channel can be calculated. The actual power of the entire system is the sum of the actual power and the rated power. The difference between the actual power and the rated power is e. The fuzzy value of the change in the difference between the actual power and the rated power is quantized as ec. E and ec are input to the input layer:

[0098] enter:

[0099] The output of the input layer is: Q1(i,j)=I1(i)(i=1,2,j=1,2,...,7), where Qi is the output function and i, j are the function's independent variables.

[0100] The input and output functions of the fuzzification layer are:

[0101] enter:

[0102] Output: O2(i,j)=exp(I2(i,j))(i=1,2,j=1,2,...,7)

[0103] Where cij is the center value of the membership function and bij is the width of the membership function. This layer is used to transmit the input value to the next layer.

[0104] The third layer is the fuzzy inference layer, whose input and output functions are described below. Its function is to calculate the weight of each input component and calculate the fuzzy rules of each node to adjust the output PID parameters.

[0105] Input: P3(i)=O2(1,j1)O2(2,j2)(i=1,2,...,49,j1,j2=1,2,...,7)

[0106] Output: Q3(i)=I3(i)(i=1,2,...,49)

[0107] The input and output of the output layer are:

[0108] enter:

[0109] Output: Q4(j)=I4(j)(j=1,2,3)

[0110] Where wij is the weight coefficient from the fuzzy inference layer to the output layer, and the output is the correction value of the PID parameter:

[0111] The output of the fuzzy neural network is the corrected value of the three PID parameters:

[0112] The output of the fuzzy neural network PID controller is: u(k)=K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]+u(k-1)

[0113] Where u(k) is the output of the system at time kT; e(k) is the system error at time kT.

[0114] For example, the three-phase PFC operating efficiency test results of the present invention are shown in Table 1. With a bus voltage of 349VAC input, 700VDC is obtained through the PFC. The load current increases from 10A to 20A, the harmonic distortion rate is 5%, and the power factor can reach 0.99.

[0115] Table 1 PFC module operating efficiency test results

[0116] The efficiency test results of the LLC full-bridge inverter are shown in Table 2. With an input voltage of 650V DC and an output power of 10kW, the efficiency can reach 97.6%.

[0117] Table 2 Full-bridge inverter efficiency

[0118] The beneficial effect of the present invention is that, compared with the prior art, the present invention solves the problem of high energy consumption of distributed inverters for DC loads in shops and shopping malls. The present invention adopts a centralized inverter power supply method, adopts the third-generation SiC MOSFET as the inverter core, uses PFC to perform power factor correction on the power supply end, and CLLLC realizes lossless on-off of the switch tube, providing a new way to energy-saving power supply. The human-machine interface (HMI) is used to set and detect the operating status and output parameters of the system. The output command is issued to the main circuit controller through the main controller, and the current and voltage signals are collected at the same time to detect the operating status of each module. The three-phase power of the power grid is supplied to the PFC module to realize power factor correction, and the voltage is adjusted to 700V DC to power the DC-DC inverter. The output is diverted by the shunt and output to loads such as lamp beads, air conditioners and other equipment to provide DC, which is distributed to electrical appliances in shops or shopping malls.

[0119] The present disclosure can be a system, method, and / or computer program product. The computer program product can include a computer-readable storage medium having computer-readable program instructions thereon for causing a processor to implement various aspects of the disclosure.

[0120] The computer-readable backup medium can be a tangible network capable of retaining and backing up instructions executed by the instruction execution network. The computer-readable backup medium can be, but is not limited to, an electrical backup network, a magnetic backup network, an optical backup network, an electromagnetic backup network, a semiconductor backup network, or any suitable combination thereof. Further examples of computer-readable backup media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (HDROM), a digital versatile disc (DXD), a memory stick, a floppy disk, a mechanically encoded network, such as a punch card or a raised structure in a groove on which instructions are backed up, or any suitable combination thereof. Computer readable backup media as used herein is not to be construed as transient signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through power line cables), or electrical signals transmitted through wires.

[0121] The computer-readable program instructions expressed herein can be downloaded from a computer-readable backup medium to each inference / processing power grid circuit, or downloaded to an external computer or external backup power grid circuit via a wireless network, such as the Internet, a local area network, a wide area network, and / or a wireless network. A wireless network can include copper transmission cables, power transmission lines, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A wireless network adapter card or wireless network interface in each inference / processing power grid circuit receives the computer-readable program instructions from the wireless network and forwards them to the computer-readable backup medium in each inference / processing power grid circuit for storage.

[0122] The computer program instructions for performing the operations of the present disclosure can be assembly language instructions, instruction set architecture (ISA) instructions, machine instructions, machine-specific instructions, microcode, firmware instructions, conditional values, or source or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Standard A, H++, and conventional procedural programming languages ​​such as "H" language or similar programming languages. The computer-readable program instructions can be executed entirely on the client computer, partially on the client computer, as a stand-alone software package, partially on the client computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the client computer via any wireless network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (such as through the Internet using an Internet service provider). In some embodiments, the electronic circuit is customized by using the status values ​​of computer-readable program instructions, such as a programmable logic circuit, a field programmable gate array (FPGA) or a programmable logic array (PLA), which can execute computer-readable program instructions to achieve various aspects of the overhead disclosure.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not deviate from the spirit and scope of the present invention should be included within the protection scope of the claims of the present invention.

Claims

1. An energy-saving centralized DC power supply device for electrical appliances, characterized in that: include: HMI, main controller, three-phase PFC, DC-DC inverter, splitter, DC load, current detection circuit and voltage detection circuit 1, and current detection circuit and voltage detection circuit 2; The HMI, the shunt, the current detection circuit and the voltage detection circuit 1, and the current detection circuit and the voltage detection circuit 2 are all connected to the main controller; The current detection circuit and the voltage detection circuit 1 are connected to the three-phase PFC, and the current detection circuit and the voltage detection circuit 1 are used to collect the current and voltage of the three-phase PFC; The current detection circuit and the voltage detection circuit 2 are connected to the DC-DC inverter device, and the current detection circuit and the voltage detection circuit 2 are used to collect the current and voltage of the DC-DC inverter device; The three-phase PFC, the DC-DC inverter, the splitter and the DC load are connected in sequence.

2. The energy-saving centralized DC power supply device for electrical appliances according to claim 1, characterized in that: The HMI is used to set and detect the operating status and output parameters of the energy-saving electrical appliance centralized DC power supply equipment, issue output commands to the main controller, and simultaneously collect the current and voltage signals of the three-phase PFC and DC-DC inverter devices through the current detection circuit and the voltage detection circuit 1 and the current detection circuit and the voltage detection circuit 2 respectively to detect the operating status of the three-phase PFC and DC-DC inverter devices; The three-phase power of the power grid is supplied to the three-phase PFC, which realizes power factor correction through its Vienna bridge and regulates the voltage to 700V DC to supply power to the DC-DC inverter, which is then shunted and output to the DC load to provide DC through the splitter.

3. The energy-saving centralized DC power supply device for electrical appliances according to claim 1, characterized in that: Three-phase PFC includes: The SiC uncontrolled rectifier bridge is composed of diodes D1-D6, the MOS tubes Q1-Q6 form a Vienna bridge, the MOS tubes Q7-Q10 form a full-bridge inverter topology structure, the L1-L3 filter inductors are connected to the full-bridge inverter topology structure, and the diodes D7-D12 connected to the full-bridge inverter topology structure are SiC mosfet reverse freewheeling diodes; The DC-DC inverter device includes: D13-D16 rectifier diodes, L4, L5 resonant inductors, transformer T1, C1-C7 filter inductors and 500kHz high frequency transformer.

4. The energy-saving centralized DC power supply device for electrical appliances according to claim 1, characterized in that: The voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 2 and the voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 1 is the same, and the voltage acquisition circuit includes: Resistors R8-R12 divide the voltage and output it to R13, R14 through linear optocoupler U2 Pin6, Pin7. Capacitor C17 filters and connects to U3. U3 is an operational amplifier and outputs it to the FDBK acquisition terminal after amplification. R18 and C21 are filtering circuits. FDBK is connected to the ADC acquisition pin of the main controller.

5. The energy-saving centralized DC power supply device for electrical appliances according to claim 1, characterized in that: The current detection circuit and the voltage detection circuit 2 and the voltage acquisition circuit structure of the current detection circuit and the voltage detection circuit 1 are the same, and the current acquisition circuit includes: Resistor R19, capacitor C22 and capacitor C23 form a current limiting and voltage stabilizing circuit. The current sensor to IL_N, IL_P is input to the U4 operational amplifier. After being amplified by the amplifier circuit composed of U4, resistor R20 and resistor R21, the signal is amplified and output to resistor R4, filtered by capacitor C3, and transmitted to IL_Fdbk. IL_Fdbk is connected to the ADC acquisition end of the main controller.

6. A method for centralized DC power supply for energy-saving electrical appliances, characterized in that: include: Step 1: Perform status detection such as PFC status detection, CLLLC status detection and splitter detection; Step 2: If a fault occurs during the status detection process, the operation of modules such as the three-phase PFC, DC-DC inverter and splitter is stopped, a fault alarm and fault code are popped up on the HMI, and the main controller terminates the subsequent steps; Step 3: If the status detection result is normal, the output parameter setting is performed by the corresponding algorithm module to calculate the parameter value required for the output.

7. The energy-saving centralized DC power supply method for electrical appliances according to claim 6, characterized in that: The energy-saving electrical appliance centralized DC power supply method also includes: During the operation of modules such as three-phase PFC, DC-DC inverter and splitter, the temperature sensor collects the temperature of the module in real time and transmits it to the main controller for detection.

8. The energy-saving centralized DC power supply method for electrical appliances according to claim 6, characterized in that: The PFC status detection methods include: The voltage acquisition circuit and the current acquisition circuit respectively collect the voltage and current values ​​of the set Collect1-Collect5 detection points, and calculate the average value of the three-phase input voltage, VMeas = (((float32_t)(V_FB_1+VIENNA_V_FB_2+V_FB_3+V3_FB_4))×ADC_CALE_FACTOR×0.25-v3MeasOffset)×2.0; take the average value as the target, calculate the error value: Voltage_error_buffer = fabs(VBusRefSlewed_buffer–VbusMeas_buffer); according to the error The difference adjusts the PWM duty cycle to maintain the three-phase voltage balance, and the current loop balance process is similar.

9. The energy-saving centralized DC power supply method for electrical appliances according to claim 6, characterized in that: The methods for detecting CLLLC status include: The voltage collection circuit and the current collection circuit respectively collect the voltage and current of the set Collect6-Collect9 collection points, collect the primary and secondary current and voltage values ​​of the transformer, and resonate with the primary side capacitor C4, inductor L1, and capacitor C5 through the upper and lower bridge arm switching frequency adjustment to make it operate in a soft switching state, and adjust the switching frequency to adjust the output voltage; The method of branch detection includes: detecting the current value of each load separately, and judging whether the load is running normally according to the collected circuit value.

10. The energy-saving centralized DC power supply method for electrical appliances according to claim 6, characterized in that: The energy-saving electrical appliance centralized DC power supply method also includes: The HMI control interface displays the voltage and current of the three phases A, B, and C, and calculates the active power and power factor of each phase to detect the operating status of the system in real time; The method for performing calculations by the corresponding algorithm module includes: The present invention constructs a fuzzy neural network PID controller running on a main controller to realize multi-channel output balance control, takes the error e and the error change rate ec as the input of the fuzzy neural network, and the correction values ​​ΔKP, ΔKI, and ΔKD of the PID parameters as the output, and realizes the online adjustment of the three parameters of PID by controlling the correction values; The fuzzy neural network adopts a two-input and three-output network structure model, which specifically includes: By detecting the output current and voltage values ​​of each channel of the shunt, the power of each channel can be calculated. The actual power of the entire system is the sum of the actual power and the rated power. The difference between the actual power and the rated power is e, and the difference changes to ec. E and ec are input as the input layer: enter: The output of the input layer is: Q1(i,j)=I1(i) (i=1,2,j=1,2,...,7) The input and output of the fuzzification layer are: enter: Output: O2(i,j)=exp(I2(i,j)) (i=1,2,j=1,2,...,7) Where cij is the center value of the membership function, and bij is the width of the membership function. The input and output of the fuzzy inference layer are: Input: P3(i)=O2(1,j1)O2(2,j2) (i=1,2,...,49,j1,j2=1,2,...,7) Output: Q3(i)=I3(i) (i=1,2,...,49) The input and output of the output layer are: enter: Output: Q4(j)=I4(j) (j=1,2,3) Where wij is the weight coefficient from the fuzzy reasoning layer to the output layer, and the output is the correction value of the PID parameter: The output of the fuzzy neural network is the corrected value of the three PID parameters: The output of the fuzzy neural network PID controller is: u(k)=K P [e(k)-e(k-1)]+K I e(k)+K D [e(k)-2e(k-1)+e(k-2)]+u(k-1) Where u(k) is the output of the system at time kT; e(k) is the system error at time kT.

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