Direct-current voltage conversion circuit and air conditioning equipment
By designing DC voltage conversion circuits for filtering, bucking, half-bridge, LLC and rectifier modules in air conditioning equipment, the problems of low efficiency and poor stability in traditional solutions are solved, and more efficient and stable voltage conversion is achieved, suitable for Efficient drive of air conditioning fans and water pumps.
Patent Information
- Application Number
- CN202420887434.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-26
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2034-04-26
AI Technical Summary
Traditional DC voltage conversion schemes have problems such as low conversion efficiency, limited adjustment range and poor output voltage stability in air conditioning fans and water pump drives.
A DC voltage conversion circuit including filtering module, step-down module, half-bridge module, LLC module and rectifier module is designed. Through filtering, step-down, AC conversion, resonant conversion and rectification, high-efficiency voltage conversion and stable output are achieved. .
It improves conversion efficiency, expands the adjustment range, and significantly improves the stability of the output voltage to meet the demand for efficient driving of air conditioners or water pumps.
Smart Images
Figure CN222283079U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power conversion, in particular to a direct current voltage conversion circuit and air conditioning equipment. Background Art
[0002] With the rapid development of modern air-conditioning technology, fans and water pumps are key components in air-conditioning systems, and the optimization and upgrading of their driving technology is particularly important.
[0003] Although traditional DC voltage conversion solutions have been used to some extent in air conditioning fan and water pump drives, they still have problems such as low conversion efficiency, limited adjustment range, and poor output voltage stability.
[0004] Therefore, there is a need for an improved DC voltage conversion circuit and air conditioning device that provide higher conversion efficiency, wider adjustment range and higher output voltage stability. Utility Model Content
[0005] In view of this, in order to solve the problems of low efficiency, limited adjustment range and poor output voltage stability during DC voltage conversion, the embodiments of the present utility model provide a DC voltage conversion circuit and air-conditioning equipment, which can provide higher conversion efficiency, wider adjustment range and higher output voltage stability.
[0006] In the first aspect, an embodiment of the utility model provides a DC voltage conversion circuit, which includes a filtering module, a buck module, a half-bridge module, an LLC module, and a rectifier module; the input end of the filtering module is connected to the voltage input end of the circuit, the output end of the filtering module is connected to the input end of the buck module, and the filtering module is used to filter the input voltage; the output end of the buck module is connected to the input end of the half-bridge module, and the buck module is used to buck the filtered input voltage; the output end of the half-bridge module is connected to the input end of the LLC module, and the half-bridge module is used to generate an AC voltage according to the stepped-down voltage; the output end of the LLC module is connected to the input end of the rectifier module, and the LLC module is used to resonate and adjust the AC voltage; the output end of the rectifier module is connected to the voltage output end of the circuit, and the rectifier module is used to rectify the AC voltage after resonant conversion and voltage adjustment, and output a DC voltage.
[0007] Preferably, the voltage input end includes a first input end and a second input end, and the filtering module includes a first filtering output end and a second filtering output end; the filtering module includes a first inductor, a first capacitor unit, a first transformer, and a second capacitor unit; one end of the first inductor is connected to the first input end of the voltage input end; the other end of the first inductor is connected to one end of the first capacitor unit through a first connection point, and the other end of the first capacitor unit is connected to the second input end of the voltage input end through a second connection point; the first connection point is also connected to one end of the first coil in the first transformer; the second connection point is also connected to one end of the second coil in the first transformer; the other end of the first coil is connected to one end of the second capacitor unit through a third connection point; the other end of the second coil is connected to the other end of the second capacitor unit through a fourth connection point; the first coil and the second coil are the primary and secondary sides of the first transformer; one end of the second capacitor unit is the first filtering output end of the filtering module; the other end of the second capacitor unit is the second filtering output end of the filtering module.
[0008] Preferably, the first capacitor unit includes a first capacitor, a second capacitor, and a third capacitor; the first capacitor and the second capacitor are connected in series to form a first capacitor branch, and the connection point between the first capacitor and the second capacitor is grounded; the third capacitor is connected in parallel with the first capacitor branch; or, the second capacitor unit includes a fourth capacitor, a fifth capacitor, and a sixth capacitor; the fourth capacitor and the fifth capacitor are connected in series to form a second capacitor branch, and the connection point between the fourth capacitor and the fifth capacitor is grounded; the sixth capacitor is connected in parallel with the second capacitor branch.
[0009] Preferably, the buck module includes a first buck output terminal and a second buck output terminal; the buck module includes a switch unit, a resistor unit, a rectifier diode unit, a second inductor, and a seventh capacitor; the switch unit is connected in parallel to the two ends of the resistor unit through a fifth connection point and a sixth connection point; the fifth connection point is connected to the first filter output terminal of the filter module; the sixth connection point is connected to the first input terminal of the rectifier diode unit; the second input terminal of the rectifier diode unit is connected to the second filter output terminal of the filter module; the first output terminal of the rectifier diode unit is connected to one end of the second inductor; the other end of the second inductor is connected to one end of the seventh capacitor through a seventh connection point; the other end of the seventh capacitor is grounded through an eighth connection point; the seventh connection point and the eighth connection point are the first buck output terminal and the second buck output terminal, respectively.
[0010] Preferably, the half-bridge module includes a first half-bridge output terminal and a second half-bridge output terminal; the half-bridge module includes a first switch tube, a second switch tube, an eighth capacitor, and a ninth capacitor; the first switch tube is connected in series with the second switch tube through a ninth connection point to form a first branch; the eighth capacitor is connected in series with the ninth capacitor through a tenth connection point to form a second branch; the first branch and the second branch are connected in parallel through an eleventh connection point and a twelfth connection point; the eleventh connection point is also connected to the first buck output terminal; the twelfth connection point is also connected to the second buck output terminal; the ninth connection point serves as the first half-bridge output terminal; and the tenth connection point serves as the second half-bridge output terminal.
[0011] Preferably, the first switch tube and the second switch tube respectively receive a first control signal and a second control signal from outside the circuit, the first switch tube is used to be turned on or off according to the first control signal, and the second switch tube is used to be turned on or off according to the second control signal, wherein the first control signal and the second control signal are complementary PWM signals with a duty cycle of 50%.
[0012] Preferably, the LLC module includes a first output terminal, a second output terminal and a third output terminal; the LLC module includes a second transformer; the two ends of the primary coil of the second transformer are respectively connected to the first half-bridge output terminal and the second half-bridge output terminal; the two ends of the secondary coil of the second transformer and the middle tap of the secondary coil serve as the first output terminal of the LLC module, the second output terminal of the LLC module and the third output terminal of the LLC module respectively.
[0013] Preferably, the rectifier module includes a first rectifier output terminal and a second rectifier output terminal; the rectifier module includes a first diode, a second diode, a tenth capacitor, and a second inductor; the positive electrode of the first diode is connected to the first output terminal of the LLC module; the positive electrode of the second diode is connected to the second output terminal of the LLC module; the cathode of the first diode and the cathode of the first diode are connected to one end of the tenth capacitor through a thirteenth connection point; the thirteenth connection point is also connected to one end of the second inductor; the other end of the second inductor serves as the first rectifier output terminal; the other end of the tenth capacitor is connected to the third output terminal of the LLC module, and the other end of the tenth capacitor serves as the second rectifier output terminal.
[0014] Preferably, the circuit also includes a first resistor, a second resistor, and a thermistor; the first resistor is connected in parallel at both ends of the first capacitor unit, and the output end of the first resistor is connected to the first signal input end of the external micro control unit; the first resistor is used for the external micro control unit to perform input voltage sampling; the second resistor is connected in parallel at both ends of the tenth capacitor, and the output end of the second resistor is connected to the second signal input end of the external micro control unit; the second resistor is used for the external micro control unit to perform output voltage sampling; the thermistor is configured to be placed in the environment where the circuit is located, and is electrically connected to the third signal input end of the micro control unit, and the thermistor is used for the external micro control unit to perform temperature sampling.
[0015] On the other hand, an air conditioning device is provided, the device comprising any one of the DC voltage conversion circuits described above.
[0016] In summary, the beneficial effects of the utility model are as follows: the utility model can effectively filter out high-frequency noise and stray signals through the filtering module to ensure that the subsequent circuit modules can work stably; the step-down module reduces the amplitude of the input voltage by changing the voltage ratio, so as to obtain the required lower voltage level; the half-bridge module receives the stepped-down DC voltage, and converts it into AC voltage through switch control, so as to achieve efficient voltage conversion and reduce energy loss; the LLC module adopts resonant conversion technology, and uses a resonant network composed of components such as inductors, capacitors and resistors to resonate and adjust the AC voltage output by the half-bridge module, so as to achieve efficient energy transmission and low loss, while maintaining the stability and accuracy of the output, thereby meeting the requirements of the air-conditioning fan or water pump for efficient driving; the rectifier module can efficiently rectify the AC voltage after the resonant conversion, and output a stable DC voltage, thereby ensuring the stable operation of the fan or water pump. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solution of the embodiment of the utility model, the drawings required for use in the embodiment of the utility model will be briefly introduced below. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work, and these are all within the protection scope of the utility model.
[0018] Figure 1 It is a schematic diagram of module connection of a DC voltage conversion circuit according to an embodiment of the utility model.
[0019] Figure 2 The figure is a schematic diagram of the circuit principle of the DC voltage conversion circuit of the embodiment of the utility model.
[0020] Figure 3 It is a schematic diagram of the structure of the air conditioning equipment of the embodiment of the utility model. DETAILED DESCRIPTION
[0021] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only intended to provide a better understanding of the present invention by illustrating examples of the present invention.
[0022] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0023] Example 1
[0024] like Figure 1 As shown, the embodiment of the utility model provides a DC voltage conversion circuit 100, which can be used as a driving circuit for a condensing fan, an evaporating fan or a water pump in an air conditioning system to drive the condensing fan, the evaporating fan or the water pump and other equipment to operate. The DC voltage conversion circuit 100 can also cooperate with other circuits and components, such as a micro control unit, a sampling component, a thermistor, etc., to achieve intelligent control.
[0025] For more information about the DC voltage conversion circuit 100 and related air-conditioning equipment, please refer to the following and related descriptions of other embodiments.
[0026] The DC voltage conversion circuit 100 includes a filter module 110 , a buck module 120 , a half-bridge module 130 , an LLC module 140 , and a rectifier module 150 .
[0027] The input end of the filter module 110 is connected to the voltage input end 101 of the DC voltage conversion circuit 100, and the output end of the filter module 110 is connected to the input end of the step-down module 120. The filter module 110 is used to filter the input voltage. The filter module 110 may include at least one of a capacitor, an inductor, a resistor, and a magnetic element.
[0028] The output end of the buck module 120 is connected to the input end of the half-bridge module 130, and the buck module 120 is used to buck the filtered input voltage. The buck module 120 can be a BUCK circuit, which can include components such as a transformer, a switch tube, an inductor, and a capacitor.
[0029] The output end of the half-bridge module 130 is connected to the input end of the LLC module 140. The half-bridge module 130 is used to generate an AC voltage according to the stepped-down voltage. The half-bridge module 130 may include a semiconductor switch device, such as a MOSFET or an IGBT, etc., to achieve voltage conversion through switch control.
[0030] The output end of the LLC module 140 is connected to the input end of the rectifier module 150. The LLC module 140 is used to perform resonant conversion and voltage regulation on the AC voltage. The LLC module 140 may include a resonant network composed of components such as an inductor, a capacitor, and a resistor.
[0031] The output end of the rectifier module 150 is connected to the voltage output end 102 of the DC voltage conversion circuit 100. The rectifier module 150 is used to rectify the AC voltage after the resonant conversion and voltage adjustment, and output a DC voltage. Exemplarily, the rectifier module 150 may include a single-phase rectifier unit composed of components such as a diode, a capacitor, a resistor, and a transformer.
[0032] The utility model can effectively filter out high-frequency noise and stray signals through the filtering module to ensure that the subsequent circuit modules can work stably; the step-down module reduces the amplitude of the input voltage by converting the voltage ratio, so as to obtain the required lower voltage level; the half-bridge module receives the DC voltage after the step-down, and converts it into AC voltage through switch control, so as to achieve efficient voltage conversion and reduce energy loss; the LLC module adopts resonant conversion technology, and utilizes a resonant network composed of components such as inductors, capacitors and resistors to perform resonant conversion and voltage adjustment on the AC voltage output by the half-bridge module, so as to achieve efficient energy transmission and low loss, while maintaining output stability and accuracy, thereby meeting the requirements of air-conditioning fans or water pumps for efficient driving; the rectifier module can efficiently rectify the AC voltage after the resonant conversion, and output a stable DC voltage, thereby ensuring the stable operation of the fan or water pump.
[0033] like Figure 2 As shown, the voltage input terminal includes a first input terminal and a second input terminal.
[0034] In some embodiments, the filter module 110 includes a first filter output terminal and a second filter output terminal.
[0035] The filter module 110 includes a first inductor L1 , a first capacitor unit, a first transformer T1 , and a second capacitor unit.
[0036] One end of the first inductor L1 is connected to the first input end of the voltage input end; the other end of the first inductor L1 is connected to one end of the first capacitor unit through the first connection point, and the other end of the first capacitor unit is connected to the second input end of the voltage input end through the second connection point; the first connection point is also connected to one end of the first coil in the first transformer T1; the second connection point is also connected to one end of the second coil in the first transformer T1; the other end of the first coil is connected to one end of the second capacitor unit through the third connection point; the other end of the second coil is connected to the other end of the second capacitor unit through the fourth connection point; the first coil and the second coil are the primary side and the secondary side of the first transformer; one end of the second capacitor unit is the first filter output end of the filter module 110; the other end of the second capacitor unit is the second filter output end of the filter module 110.
[0037] The utility model integrates multiple components such as inductors, capacitors and transformers through the design of the above-mentioned filtering module to form a composite filtering system. Through the combined effect of the inductors, capacitors and transformers, the filtering module can effectively filter out high-frequency noise and clutter in the input voltage, making the output voltage purer and more stable; the inductor has a blocking effect on the AC signal, while the capacitor has a conducting effect on the AC signal. The combination of the two can form a low-pass filter to effectively filter out high-frequency interference; at the same time, the electromagnetic induction relationship between the primary and secondary coils of the transformer can further improve the filtering effect.
[0038] In some embodiments, the first capacitor unit includes a first capacitor C1, a second capacitor C2, and a third capacitor C3; the first capacitor C1 and the second capacitor C2 are connected in series to form a first capacitor branch, and the connection point between the first capacitor C1 and the second capacitor C2 is grounded; the third capacitor C3 is connected in parallel with the first capacitor branch; or the second capacitor unit includes a fourth capacitor C4, a fifth capacitor C5, and a sixth capacitor C6; the fourth capacitor C4 and the fifth capacitor C5 are connected in series to form a second capacitor branch, and the connection point between the fourth capacitor C4 and the fifth capacitor C5 is grounded; the sixth capacitor C6 is connected in parallel with the second capacitor branch.
[0039] By connecting capacitors of different capacitance values in series or in parallel, the filter module can achieve filtering effects in multiple frequency bands. Grounding the connection points between capacitors can reduce electromagnetic interference and improve circuit stability.
[0040] In some embodiments, the buck module 120 includes a first buck output terminal and a second buck output terminal. The buck module 120 includes a switch unit K1, a resistor unit R4, a rectifier diode unit 121, a second inductor L2, and a seventh capacitor C7. Among them, the switch unit K1 may include at least one of a pull switch, a push button switch, a toggle switch, etc. The rectifier diode unit may include a full-bridge rectifier circuit, that is, four rectifier diodes are connected in the form of a bridge circuit. In each operating cycle of the full-bridge rectifier circuit, only two diodes are operating at the same time. Through the unidirectional conduction function of the diode, the alternating current can be converted into a unidirectional direct current pulsating voltage. The second inductor can be an inductor with a magnetic core. The resistor unit R4 may include a resistor or a resistor network, etc.
[0041] The switch unit K1 is connected in parallel at both ends of the resistor unit R4 through the fifth connection point and the sixth connection point; the fifth connection point is connected to the first filter output end of the filter module; the sixth connection point is connected to the first input end of the rectifier diode unit 121; the second input end of the rectifier diode unit 121 is connected to the second filter output end of the filter module; the first output end of the rectifier diode unit 121 is connected to one end of the second inductor L2; the other end of the second inductor L2 is connected to one end of the seventh capacitor C7 through the seventh connection point; the other end of the seventh capacitor C7 is grounded through the eighth connection point, and the second output end of the rectifier diode unit 121 is connected to the eighth connection point; the seventh connection point and the eighth connection point are the first buck output end and the second buck output end, respectively.
[0042] The step-down module can effectively reduce the input voltage to the required output voltage through the coordinated operation of the switch unit K1 , the resistor unit R4 , the rectifier diode unit 121 , the second inductor L2 and the seventh capacitor C7 .
[0043] In some embodiments, the half-bridge module 130 includes a first half-bridge output terminal, a second half-bridge output terminal, and a third half-bridge output terminal; the half-bridge module includes a first switch tube Q1 and a second switch tube Q2.
[0044] The first switch tube Q1 is connected in series with the second switch tube Q2 through the ninth connection point to form a first series branch; one end of the first series branch is connected to the first buck output terminal, and this end of the first series branch serves as the first half-bridge output terminal; the other end of the first series branch is connected to the second buck output terminal, and this other end of the first series branch serves as the second half-bridge output terminal, and the ninth connection point also serves as the third half-bridge output terminal.
[0045] In some embodiments, the first switch tube Q1 and the second switch tube Q2 respectively receive a first control signal and a second control signal from outside the circuit, the first switch tube Q1 is used to be turned on or off according to the first control signal, and the second switch tube Q2 is used to be turned on or off according to the second control signal, wherein the first control signal and the second control signal are complementary PWM signals with a duty cycle of 50%.
[0046] The first switch tube Q1 and the second switch tube Q2 can be IGBT tubes or power MOS tubes, etc. When the first switch tube Q1 and the second switch tube Q2 are connected in series, the emitter of the first switch tube Q1 is connected to the collector of the second switch tube Q2 through the ninth connection point, the collector of the first switch tube Q1 is connected to the first buck output terminal, and the collector of the first switch tube Q1 serves as the first half-bridge output terminal, the emitter of the second switch tube Q2 is connected to the second buck output terminal, and the emitter of the second switch tube Q2 serves as the second half-bridge output terminal. The first switch tube Q1 and the second switch tube Q2 receive the first control signal and the second control signal from the outside of the circuit (for example, a micro control unit) through their respective gates.
[0047] In some embodiments, LLC module 140 includes a first output terminal, a second output terminal, and a third output terminal.
[0048] The LLC module 140 includes an eighth capacitor C8, a ninth capacitor C9, and a second transformer T2. The eighth capacitor C8 is connected in series with the ninth capacitor C9 through the tenth connection point to form a second series branch, one end of the second series branch is connected to the first half-bridge output end, and the other end of the second series branch is connected to the second half-bridge output end. The two ends of the primary coil of the second transformer T2 are connected to the third half-bridge output end and the tenth connection point, respectively; the two ends of the secondary coil of the second transformer T2 and the middle tap of the secondary coil serve as the first output end of the LLC module 140, the second output end of the LLC module 140, and the third output end of the LLC module 140, respectively.
[0049] The utility model can generate an AC voltage and realize efficient energy conversion by controlling the alternating on and off of the first switch tube Q1 and the second switch tube Q2; since a complementary PWM signal with a duty cycle of 50% is used as a control signal, the on and off timing of the first switch tube Q1 and the second switch tube Q2 can be accurately controlled, and zero voltage switching can be realized, and the voltage or current is reduced to zero at the moment of switching of the switch tube, thereby reducing power loss and electromagnetic interference in the switching process and improving the efficiency and reliability of the system.
[0050] In some embodiments, the rectifier module 150 includes a first rectifier output terminal and a second rectifier output terminal.
[0051] The rectifier module 150 includes a first diode D1 , a second diode D2 , a tenth capacitor C10 , and a third inductor L3 .
[0052] The anode of the first diode D1 is connected to the first output terminal of the LLC module 140; the anode of the second diode D2 is connected to the second output terminal of the LLC module 140; the cathode of the first diode D1 and the cathode of the first diode D2 are connected to one end of the tenth capacitor C10 through the thirteenth connection point; the thirteenth connection point is also connected to one end of the third inductor L3; the other end of the third inductor L3 serves as the first rectifier output terminal; the other end of the tenth capacitor C10 is connected to the third output terminal of the LLC module 140, and the other end of the tenth capacitor C10 serves as the second rectifier output terminal.
[0053] Through the specific connection method of the first diode D1 and the second diode D2, the rectifier module can efficiently convert the AC voltage output by the LLC module into a DC voltage, ensuring that only the AC voltage in the positive half cycle can pass through the diode, thereby realizing half-wave rectification and improving the rectification efficiency; the combination of the tenth capacitor C10 and the third inductor L3 plays a filtering role, which can filter out the residual AC components and noise in the rectified DC voltage, thereby providing a purer and more stable DC output.
[0054] In some embodiments, Figure 2 As shown, the DC voltage conversion circuit 100 further includes a first resistor R1, a second resistor R, a third resistor R3, and a thermistor RT.
[0055] The first resistor R1 is connected in parallel at both ends of the first capacitor unit, and the output end of the first resistor R1 (i.e., the two ends of the first resistor R1, used to output the voltage across the first resistor R1, and the corresponding position in the figure is only used to illustrate the output end) is connected to the first signal input end of the micro control unit U1; the first resistor R1 is used for the external micro control unit U1 to perform input voltage sampling.
[0056] The second resistor R2 is connected in parallel at both ends of the tenth capacitor C10, and the output end of the second resistor R2 (i.e., the two ends of the second resistor R2, used to output the voltage across the second resistor R2, and the corresponding position in the figure is only used to illustrate the output end) is connected to the second signal input end of the micro control unit U2; the second resistor R2 is used for the external micro control unit U1 to sample the output voltage.
[0057] The third resistor R3 is connected in series to the output end of the DC voltage conversion circuit 100, and the output end of the third resistor R3 (i.e., the two ends of the third resistor R3, used to output the voltage across the two ends of the third resistor R3, and the corresponding position in the figure is only used to illustrate the output end) is connected to the third signal input end of the micro control unit U2; the third resistor R3 is used for the external micro control unit U1 to perform output current sampling, and the current value can be obtained by dividing the voltage across the two ends of the third resistor R3 by the resistance value of the third resistor R3.
[0058] The thermistor RT is configured to be placed in the environment where the DC voltage conversion circuit 100 is located, and is electrically connected to the fourth signal input terminal of the micro control unit U1. The thermistor RT is used for the external micro control unit U1 to perform temperature sampling.
[0059] The external micro control unit U1 refers to a micro control unit outside the DC voltage conversion circuit 100. The external micro control unit U1 may be an MCU chip.
[0060] The first resistor R1 and the second resistor R2 are used for the microcontroller U1 to sample the input and output voltages, which is beneficial to obtain accurate data of the input and output voltages in real time, so that the system can adjust the output voltage of the DC voltage conversion circuit 100 according to actual needs, thereby ensuring the stable operation of equipment such as condensing fans, evaporating fans or water pumps. At the same time, the third resistor R3 is used for the microcontroller U1 to sample the current, which is convenient for the microcontroller U1 to obtain the output current, so as to make corresponding adjustments and optimizations. The thermistor RT is used to sense the temperature changes of the circuit working environment in real time, which is beneficial for the microcontroller U1 to adjust the output of the DC voltage conversion circuit 100 according to the corresponding temperature data, so as to avoid performance degradation or equipment damage caused by overheating.
[0061] Example 2
[0062] Figure 3 A schematic diagram of the structure of an air conditioning device 300 provided in an embodiment of the utility model is shown.
[0063] like Figure 3 As shown, the air conditioning device 300 includes the DC voltage conversion circuit 100 described in some embodiments of Example 1. The air conditioning device 300 also includes a condensing fan, an evaporating fan or a water pump 310. The DC voltage conversion circuit 100 can provide a DC voltage to drive the condensing fan, the evaporating fan or the water pump 310 to work.
[0064] For more information about each module, component or circuit, please refer to the relevant description in Example 1.
[0065] The DC voltage conversion circuit 100 provided by the utility model is described in detail above. Those skilled in the art will further understand that the various illustrative logic blocks, modules, circuits and algorithm steps described in conjunction with the embodiments disclosed herein can be implemented as electronic hardware, computer software or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, various illustrative components, blocks, modules, circuits and steps have been described above in terms of functionality. Whether the functionality is implemented as hardware or software depends on the specific use and the design constraints imposed on the entire system. Those skilled in the art can implement the described functionality in different ways for each specific use. All equivalent structures or equivalent process transformations made using the contents of the specification and drawings of the utility model, or directly or indirectly used in other related technical fields, are similarly included in the scope of patent protection of the utility model. It should not be understood as a limitation on the utility model.
[0066] The above is only a specific implementation of the present invention. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present invention is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention.
Claims
1. A DC voltage conversion circuit, characterized in that: The circuit includes a filtering module, a buck module, a half-bridge module, an LLC module, and a rectifier module; The input end of the filter module is connected to the voltage input end of the circuit, the output end of the filter module is connected to the input end of the step-down module, and the filter module is used to filter the input voltage; The output end of the step-down module is connected to the input end of the half-bridge module, and the step-down module is used to step down the filtered input voltage; The output end of the half-bridge module is connected to the input end of the LLC module, and the half-bridge module is used to generate an AC voltage according to the stepped-down voltage; The output end of the LLC module is connected to the input end of the rectifier module, and the LLC module is used to perform resonant conversion and voltage adjustment on the AC voltage; The output end of the rectifier module is connected to the voltage output end of the circuit, and the rectifier module is used to rectify the AC voltage after resonant conversion and voltage adjustment, and output a DC voltage.
2. The circuit according to claim 1, characterized in that The voltage input terminal includes a first input terminal and a second input terminal, and the filter module includes a first filter output terminal and a second filter output terminal; The filtering module includes a first inductor, a first capacitor unit, a first transformer, and a second capacitor unit; One end of the first inductor is connected to a first input end of the voltage input end; the other end of the first inductor is connected to one end of the first capacitor unit through a first connection point, and the other end of the first capacitor unit is connected to a second input end of the voltage input end through a second connection point; The first connection point is also connected to one end of the first coil in the first transformer; the second connection point is also connected to one end of the second coil in the first transformer; The other end of the first coil is connected to one end of the second capacitor unit through a third connection point; the other end of the second coil is connected to the other end of the second capacitor unit through a fourth connection point; The first coil and the second coil are the primary side and the secondary side of the first transformer; One end of the second capacitor unit is the first filter output end of the filter module; the other end of the second capacitor unit is the second filter output end of the filter module.
3. The circuit according to claim 2, characterized in that The first capacitor unit includes a first capacitor, a second capacitor, and a third capacitor; the first capacitor and the second capacitor are connected in series to form a first capacitor branch, and the connection point between the first capacitor and the second capacitor is grounded; the third capacitor is connected in parallel to the first capacitor branch; or, The second capacitor unit includes a fourth capacitor, a fifth capacitor, and a sixth capacitor; the fourth capacitor and the fifth capacitor are connected in series to form a second capacitor branch, and the connection point between the fourth capacitor and the fifth capacitor is grounded; the sixth capacitor is connected in parallel to the second capacitor branch.
4. The circuit according to claim 2, characterized in that The buck module includes a first buck output terminal and a second buck output terminal; The step-down module includes a switch unit, a resistor unit, a rectifier diode unit, a second inductor, and a seventh capacitor; The switch unit is connected in parallel to both ends of the resistance unit through a fifth connection point and a sixth connection point; The fifth connection point is connected to the first filter output terminal of the filter module; The sixth connection point is connected to the first input end of the rectifier diode unit; the second input end of the rectifier diode unit is connected to the second filter output end of the filter module; The first output terminal of the rectifier diode unit is connected to one end of the second inductor; The other end of the second inductor is connected to one end of the seventh capacitor through a seventh connection point; The other end of the seventh capacitor is grounded through an eighth connection point; the second output end of the rectifier diode unit is connected to the eighth connection point; The seventh connection point and the eighth connection point are the first buck output terminal and the second buck output terminal respectively.
5. The circuit according to claim 4, characterized in that The half-bridge module includes a first half-bridge output end, a second half-bridge output end and a third half-bridge output end; The half-bridge module includes a first switch tube and a second switch tube; The first switch tube is connected in series with the second switch tube through a ninth connection point to form a first series branch; one end of the first series branch is connected to the first buck output end, and the one end of the first series branch serves as the first half-bridge output end; the other end of the first series branch is connected to the second buck output end, and the other end of the first series branch serves as the second half-bridge output end, and the ninth connection point serves as the third half-bridge output end.
6. The circuit according to claim 5, characterized in that The first switch tube and the second switch tube respectively receive a first control signal and a second control signal from outside the circuit, the first switch tube is used to be turned on or off according to the first control signal, and the second switch tube is used to be turned on or off according to the second control signal, wherein the first control signal and the second control signal are complementary PWM signals with a duty cycle of 50%.
7. The circuit according to claim 5, characterized in that The LLC module includes a first output terminal, a second output terminal and a third output terminal; The LLC module includes an eighth capacitor, a ninth capacitor and a second transformer; The eighth capacitor is connected in series with the ninth capacitor via the tenth connection point to form a second series branch; One end of the second series branch is connected to the output end of the first half-bridge, and the other end of the second series branch is connected to the output end of the second half-bridge; The two ends of the primary coil of the second transformer are respectively connected to the third half-bridge output end and the tenth connection point; the two ends of the secondary coil of the second transformer and the middle tap of the secondary coil serve as the first output end of the LLC module, the second output end of the LLC module and the third output end of the LLC module respectively.
8. The circuit according to claim 7, characterized in that The rectifier module comprises a first rectifier output terminal and a second rectifier output terminal; The rectifier module includes a first diode, a second diode, a tenth capacitor, and a third inductor; An anode of the first diode is connected to the first output terminal of the LLC module; An anode of the second diode is connected to the second output terminal of the LLC module; The cathode of the first diode and the cathode of the first diode are connected to one end of the tenth capacitor through a thirteenth connection point; the thirteenth connection point is also connected to one end of the third inductor; the other end of the third inductor serves as the first rectifier output end; The other end of the tenth capacitor is connected to the third output end of the LLC module, and the other end of the tenth capacitor serves as the second rectifier output end.
9. The circuit according to claim 8, characterized in that The circuit also includes a first resistor, a second resistor, a third resistor, and a thermistor; The first resistor is connected in parallel to both ends of the first capacitor unit, and the output end of the first resistor is connected to the first signal input end of the external micro control unit; the first resistor is used for the external micro control unit to perform input voltage sampling; The second resistor is connected in parallel to both ends of the tenth capacitor, and the output end of the second resistor is connected to the second signal input end of the external micro control unit; the second resistor is used for the external micro control unit to perform output voltage sampling; The third resistor is connected in series to the output end of the circuit, and the output end of the third resistor is connected to the third signal input end of the external micro control unit; the third resistor is used for the external micro control unit to perform output current sampling; The thermistor is configured to be placed in the environment where the circuit is located and electrically connected to the fourth signal input terminal of the external micro control unit. The thermistor is used for the external micro control unit to perform temperature sampling.
10. An air conditioning device, characterized in that: The device comprises a DC voltage conversion circuit according to any one of claims 1-9.