Multifunctional DCDC converter

Abstract

The utility model relates to a multifunctional DCDC converter, which effectively solves the problems that a photovoltaic converter and an energy storage PCS which are common in the market at present are usually separately designed and used, and are lack of flexibility and universality and the like. Comprising a control module arranged in a case, the control module comprises a control circuit board, and the control circuit board is provided with a digital signal processor, a current and voltage operational amplifier electrically connected with the digital signal processor, a PWM level converter electrically connected with the digital signal processor and a first optocoupler; the power module comprises a power circuit board, a voltage sensor, an operational amplifier electrically connected with the voltage sensor, a second optocoupler electrically connected with the first optocoupler, and a triode electrically connected with the second optocoupler; according to the utility model, the converter, the energy storage battery and the photovoltaic assembly are combined, so that the integrated energy management is realized, the flexibility and universality of the system are greatly improved, the number of equipment and the complexity of the system are reduced, and the cost is also reduced at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage photovoltaics, in particular to a multifunctional DCDC converter. Background Art

[0002] With the growing global demand for clean energy, photovoltaic (PV) energy and energy storage technologies are becoming increasingly important tools for addressing energy supply and environmental protection challenges. As a renewable energy source, PV energy offers advantages such as being pollution-free and widely distributed, leading to its widespread application in the energy industry. However, the volatility and intermittent nature of PV energy pose challenges to its large-scale application. Therefore, it needs to be combined with energy storage technologies to balance the gap between supply and demand and improve energy efficiency.

[0003] However, the existing photovoltaic power generation system still has the following problems in the design and use of photovoltaic modules and energy storage batteries:

[0004] 1. In photovoltaic power generation systems, photovoltaic panels and energy storage batteries are two key components. However, the photovoltaic converters and energy storage PCS commonly found on the market are usually designed and used separately, lacking flexibility and versatility.

[0005] 2. The existing converters are not highly integrated and cannot adjust multiple working modes, which limits the universality of the converters. Utility Model Content

[0006] In view of the above problems, the present invention provides a multifunctional DCDC converter, which has the advantages of high flexibility, low cost and long equipment service life.

[0007] The technical solution is that the utility model includes:

[0008] The control module includes a control circuit board, on which a digital signal processor, an operational amplifier unit electrically connected to the digital signal processor, a PWM level converter electrically connected to the digital signal processor, and a first optical coupler are provided;

[0009] A power module comprising a power circuit board, a voltage sensor, a voltage operational amplifier electrically connected to the voltage sensor, a Hall sensor, the Hall sensor being connected to a current operational amplifier, the output ends of the voltage operational amplifier and the current operational amplifier being electrically connected to a digital signal processor via wiring, and a second optocoupler electrically connected to the first optocoupler, the second optocoupler being electrically connected to a transistor;

[0010] Also included is an IGBT driver electrically connected to the PWM level converter, and an IGBT electrically connected to the IGBT driver;

[0011] The filter module includes a filter circuit board, the voltage sensor electrically connected to the output end of the filter circuit board, a low-voltage side DC soft-start relay electrically connected to point C of the transistor and the fourth pin of the second optocoupler, a low-voltage side DC incoming line relay, and an inductor. The wire of the IGBT output end passes through the Hall sensor and is connected to the input end of the inductor. The filter module can be externally connected to a photovoltaic module or an energy storage battery;

[0012] A front panel interaction module includes a button, a program download port, and a display device, and the digital signal processor is electrically connected to the front panel interaction module;

[0013] A heat dissipation module, comprising a heat dissipation fan, wherein the heat dissipation fan is connected to point C of the transistor and the fourth pin of the second optocoupler;

[0014] A high-power terminal is provided outside the chassis, and input terminals are respectively provided on the power circuit board and the filter circuit board. The high-power terminals are respectively electrically connected to the corresponding input terminals, and the photovoltaic components or energy storage batteries are respectively electrically connected to the high-power terminals.

[0015] Preferably, the IGBT includes a thermistor to convert the temperature signal into an electrical signal and transmit it to the control module to adjust the speed of the cooling fan.

[0016] Preferably, the front panel interaction module further includes a dip switch, and the dip switch is connected to the GPIO interface of the digital signal processor via a wire strip.

[0017] Preferably, the switching program between the DIP switch and the digital signal processor includes: a constant voltage charging program, a constant current charging program, a constant voltage discharging program, a constant current discharging program and a photovoltaic converter maximum power point tracking program.

[0018] Preferably, the filter circuit board is a three-way LC filter structure.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. Integrated energy management is achieved through the combination of converters, energy storage batteries and photovoltaic modules, which greatly improves the flexibility and versatility of the system, reduces the number of devices and system complexity, and also reduces costs.

[0021] 2. Through software integration, this inverter supports multiple operating modes, including but not limited to the constant current charge and discharge mode of PCS, the constant voltage charge and discharge mode, and the maximum power point tracking (MPPT) control mode of the photovoltaic inverter. This enables the device to flexibly adjust its operating status according to actual energy demand and storage conditions, and optimize energy use and management.

[0022] 3. Through the settings of temperature sampling circuit, control module and power module, the fan speed can be accurately controlled and adjusted according to the actual heat dissipation requirements of the inverter to achieve efficient heat dissipation. At the same time, reasonable temperature control can reduce the damage caused by overheating of the inverter and extend the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a hardware layout diagram of the present utility model.

[0024] Figure 2 It is a schematic diagram of the hardware layout between the modules in the present invention.

[0025] Figure 3 This is the DC-DC topology diagram of the utility model.

[0026] Figure 4 This is a schematic diagram of the temperature sampling circuit in the utility model.

[0027] Figure 5 This is the logic block diagram of the DIP switch in the utility model.

[0028] Figure 6 This is the temperature control logic block diagram of the utility model. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] Depend on Figures 1 to 3 Give, including those placed inside the chassis:

[0031] The control module includes a control circuit board, which uses a high-speed floating-point DSP TMS320F28335PGFA for real-time calculations and PWM output control. The control circuit board is provided with a digital signal processor, an operational amplifier unit electrically connected to the digital signal processor, and the operational amplifier unit includes voltage and current operational amplifiers, a PWM level converter connected to the digital signal processor, and a first optical coupler;

[0032] The power module includes a power circuit board (the power circuit board adopts a three-phase bridge GD150FFY120C6S module with a vertical front panel air duct design), a voltage sensor, a voltage operational amplifier electrically connected to the voltage sensor, and a Hall sensor, the Hall sensor is connected to a current operational amplifier, the output ends of the voltage operational amplifier and the current operational amplifier are respectively electrically connected to the digital signal processor through a cable, and a second optocoupler electrically connected to the first optocoupler, the second optocoupler is electrically connected to a transistor, and the above circuit is divided into five paths, the output ends of the five transistors and the fourth pin of the second optocoupler are respectively connected to the fan, the high-voltage side DC incoming line relay, the high-voltage side DC soft start relay, and the low-voltage side DC incoming line relay and the low-voltage side DC soft start relay in the filter module;

[0033] Also included is an IGBT driver electrically connected to the PWM level converter, and an IGBT electrically connected to the IGBT driver;

[0034] The filter module includes a filter circuit board, the voltage sensor electrically connected to the output end of the filter circuit board, a low-voltage side DC soft-start relay connected to point C of the transistor and the fourth pin of the second optocoupler, and a low-voltage side DC incoming line relay. It also includes an inductor, and the wire of the IGBT output end passes through the Hall sensor and is connected to the input end of the inductor. The filter module can be externally connected to a photovoltaic module or an energy storage battery;

[0035] A front panel interaction module includes buttons, a program download port, and a display device. In this embodiment, the display device is an OLED display that can display system-related fault information, such as DC hardware overvoltage fault, DC software overvoltage fault, DC hardware overcurrent fault, DC software overcurrent fault, IGBT overtemperature fault, undervoltage fault, etc. The digital signal processor is electrically connected to the front panel interaction module;

[0036] The heat dissipation module includes a heat dissipation fan, which is connected to point C of the transistor and the fourth pin of the second optocoupler, and the heat dissipation fan is controlled by PWM;

[0037] A high-power terminal is provided outside the chassis, and input terminals are respectively provided on the power circuit board and the filter circuit board. The high-power terminals are electrically connected to the corresponding input terminals, and the photovoltaic modules or energy storage batteries are electrically connected to the high-power terminals. Through the combination of the above-mentioned converter, energy storage battery and photovoltaic module, integrated energy management is achieved, which greatly improves the flexibility and versatility of the system, reduces the number of devices and the complexity of the system, and also reduces the cost.

[0038] refer to Figure 3 As shown in the figure, the following supplementary explanations are given for the DC-DC topology diagram:

[0039] When the system starts working, the incoming line relay and soft start relay will operate in sequence to allow power to enter the circuit.

[0040] IGBTs are switching elements that can be turned on or off as needed, allowing current to flow or preventing it from flowing. In this circuit, there are three groups of IGBTs (IGBT1, 2; IGBT3, 4; IGBT5, 6). Each group of three IGBTs is staggered and connected in parallel to form a so-called three-phase bridge structure, which is used to control the direction and magnitude of the current.

[0041] The IGBTs are turned on and off in a specific order. In buck mode control, current flows from X3, passes through inductors L7 and L8, and then flows to X6. During this process, the inductor stores and releases energy to keep the current stable.

[0042] The soft-start resistor limits the current when the system starts, protecting the circuit from excessive current.

[0043] When the system reaches a stable state, the soft-start resistor will be short-circuited and no longer participate in the work.

[0044] refer to Figure 4 and Figure 6 As shown, the power module also includes a thermistor, which converts the temperature signal into an electrical signal and transmits it to the control module to adjust the speed of the cooling fan.

[0045] Complementing the temperature control of the converter are:

[0046] First, the signal sampled by the temperature circuit is fed back to the digital signal processor for analysis, enabling real-time monitoring of the operating temperature of the converter power module and calculating the appropriate fan speed using a built-in algorithm.

[0047] Then, the digital signal processor generates the corresponding PWM signal to adjust the fan speed;

[0048] Secondly, the control program will judge the calculated temperature to see if it exceeds the preset temperature T1. If it does, the upper limit of the power output will be limited, and a prompt will be displayed on the front panel indicating that the temperature has exceeded the preset temperature T1.

[0049] Then the temperature is judged again to determine whether the temperature exceeds the preset temperature T2. If it exceeds the preset temperature T2, the output power will be reduced;

[0050] Finally, determine whether the temperature exceeds the preset temperature T3. If it exceeds, an overtemperature fault will be reported and protection action will be taken to disconnect the relays on the high-voltage side and the low-voltage side and lock the PWM output. At the same time, the set values ​​of T1, T2, and T3 can be modified on the LED display module.

[0051] Considering that the existing converter has a low level of integration, firstly, it does not have the function of adjusting multiple working modes, and secondly, the program download port is set in the chassis. When changing the program or verifying different algorithms, it is necessary to disassemble the chassis for adjustment, which is very troublesome. The front panel interaction module also includes a dip switch, which is connected to the GPIO interface of the digital signal processor through a wire row. The DSP reads the value of the dip switch through the GPIO port and makes judgments based on the value;

[0052] refer to Figure 5 As an example of the program types controlled by the dip switch, the switching programs between the dip switch and the digital signal processor include: a constant voltage charging program, a constant current charging program, a constant voltage discharge program, a constant current discharge program, and a photovoltaic converter maximum power tracking program.

[0053] The following are examples of the values ​​of the DIP switches:

[0054] When the value is equal to 1, the energy storage PCS constant voltage charging control program is executed;

[0055] When the value is equal to 2, the energy storage PCS constant current charging is executed;

[0056] When the value is equal to 3, the PCS constant voltage discharge control program is executed;

[0057] When the value is equal to 4, the energy storage PCS constant current discharge control program is executed;

[0058] When the value is equal to 5, the maximum power point tracking (MPPT) control mode of the photovoltaic inverter is executed. When working in different control modes, the controlled quantity can be modified through the front panel LED display module. In the PCS constant current charge and discharge control mode, the output current can be modified, and in the PCS constant voltage charge and discharge control mode, the output voltage can be modified, realizing simple and convenient operation. At the same time, the hardware dial changes will be monitored in real time, and the working status can be switched in real time.

[0059] The filter circuit board has a three-way LC filter structure. The three-way LC filter structure refers to a design in which three groups of LC filters are used to filter each phase of the three-phase AC power in a power electronic converter or power supply system, thereby reducing high-frequency noise and ripple in the current or voltage of each phase, making the output smoother and closer to an ideal sine waveform.

[0060] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multifunctional DCDC converter, characterized in that: Included inside the chassis: The control module includes a control circuit board, on which a digital signal processor, an operational amplifier unit electrically connected to the digital signal processor, a PWM level converter electrically connected to the digital signal processor, and a first optical coupler are provided; A power module comprising a power circuit board, a voltage sensor, a voltage operational amplifier electrically connected to the voltage sensor, a Hall sensor, the Hall sensor being connected to a current operational amplifier, the output ends of the voltage operational amplifier and the current operational amplifier being electrically connected to a digital signal processor via wiring, and a second optocoupler electrically connected to the first optocoupler, the second optocoupler being electrically connected to a transistor; Also included is an IGBT driver electrically connected to the PWM level converter, and an IGBT electrically connected to the IGBT driver; The filter module includes a filter circuit board, the voltage sensor electrically connected to the output end of the filter circuit board, a low-voltage side DC soft-start relay electrically connected to point C of the transistor and the fourth pin of the second optocoupler, a low-voltage side DC incoming line relay, and an inductor. The wire of the IGBT output end passes through the Hall sensor and is connected to the input end of the inductor. The filter module can be externally connected to a photovoltaic module or an energy storage battery; A front panel interaction module includes a button, a program download port, and a display device, and the digital signal processor is electrically connected to the front panel interaction module; A heat dissipation module, comprising a heat dissipation fan, wherein the heat dissipation fan is connected to point C of the transistor and the fourth pin of the second optocoupler; A high-power terminal is provided outside the chassis, and input terminals are respectively provided on the power circuit board and the filter circuit board. The high-power terminals are respectively electrically connected to the corresponding input terminals, and the photovoltaic components or energy storage batteries are respectively electrically connected to the high-power terminals.

2. The multifunctional DCDC converter according to claim 1, characterized in that: The IGBT includes a thermistor that converts the temperature signal into an electrical signal and transmits it to the control module to adjust the speed of the cooling fan.

3. The multifunctional DCDC converter according to claim 2, characterized in that: The front panel interaction module further includes a dip switch, and the dip switch is connected to the GPIO interface of the digital signal processor via a wire row.

4. The multifunctional DCDC converter according to claim 3, characterized in that: The switching program between the DIP switch and the digital signal processor includes: a constant voltage charging program, a constant current charging program, a constant voltage discharging program, a constant current discharging program and a photovoltaic converter maximum power tracking program.

5. The multifunctional DCDC converter according to claim 4, characterized in that: The filter circuit board is a three-way LC filter structure.

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