CN114517990A - Control circuit and method for thermoelectric refrigeration refrigerator - Google Patents
Control circuit and method for thermoelectric refrigeration refrigerator Download PDFInfo
- Publication number
- CN114517990A CN114517990A CN202011305123.8A CN202011305123A CN114517990A CN 114517990 A CN114517990 A CN 114517990A CN 202011305123 A CN202011305123 A CN 202011305123A CN 114517990 A CN114517990 A CN 114517990A
- Authority
- CN
- China
- Prior art keywords
- voltage
- refrigerator
- sampling
- control
- output
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000005057 refrigeration Methods 0.000 title claims abstract description 57
- 238000000034 method Methods 0.000 title claims abstract description 9
- 238000005070 sampling Methods 0.000 claims description 75
- 238000001816 cooling Methods 0.000 claims description 25
- 230000000087 stabilizing effect Effects 0.000 claims description 11
- 239000003990 capacitor Substances 0.000 claims description 9
- 230000006641 stabilisation Effects 0.000 claims description 2
- 238000011105 stabilization Methods 0.000 claims description 2
- 230000009467 reduction Effects 0.000 abstract description 4
- 238000010586 diagram Methods 0.000 description 8
- 230000001276 controlling effect Effects 0.000 description 6
- 238000001914 filtration Methods 0.000 description 5
- 230000001105 regulatory effect Effects 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000004308 accommodation Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B21/00—Machines, plants or systems, using electric or magnetic effects
- F25B21/02—Machines, plants or systems, using electric or magnetic effects using Peltier effect; using Nernst-Ettinghausen effect
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
- F25D29/00—Arrangement or mounting of control or safety devices
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D23/00—Control of temperature
- G05D23/19—Control of temperature characterised by the use of electric means
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
- Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
Abstract
The invention relates to a control circuit of a thermoelectric refrigeration refrigerator, which acquires data parameters through a control unit, namely the temperature in the refrigerator of the thermoelectric refrigeration refrigerator, the set temperature of the thermoelectric refrigeration refrigerator and the working voltage currently supplied to a refrigerating sheet of the thermoelectric refrigeration refrigerator, generates a corresponding control signal according to the related data parameters and sends the control signal to a switch power supply, so that the switch power supply can adjust the output voltage supplied to the refrigerating sheet according to the control signal, namely, an output adjustable switch power supply is formed to supply power to the refrigerating sheet; therefore, the traditional DC/DC voltage reduction circuit arranged on the control board in the prior art is not needed, so that the electric control cost of the thermoelectric refrigeration refrigerator is obviously reduced. In addition, the invention also relates to a control method of the thermoelectric refrigeration refrigerator.
Description
Technical Field
The invention relates to the technical field of thermoelectric refrigeration refrigerators, in particular to a control circuit and a control method of a thermoelectric refrigeration refrigerator.
Background
With the improvement of the consumption level of the present residents, people increasingly advocate leisure and high-quality life, and the refrigerator is used as a household necessity and also becomes a basic configuration in other outdoor leisure or accommodation occasions. Depending on the type of refrigerator configured, this includes not only conventional compressor refrigerators but also absorption refrigerators and thermoelectric refrigeration (i.e., semiconductor) refrigerators; particularly, the thermoelectric refrigeration refrigerator has the advantages of low cost, free inclination, light weight and the like, so that the thermoelectric refrigeration refrigerator has a large market in the field of mobile refrigerators, such as hotels or retail markets.
The refrigeration principle of the thermoelectric refrigeration refrigerator is as follows: by using the Peltier refrigeration element (i.e. refrigeration piece) and the Peltier principle, the cold energy can be continuously generated by direct current and then configuring a heat exchanger (such as heat dissipation aluminum, a fan and the like). This allows the thermoelectric refrigeration refrigerator to have the following advantages: the refrigerator has low cost, light weight and small size and is easy to manufacture; and the refrigeration system is not influenced by direction and refrigeration is not influenced by random inclination, so that the refrigerator is particularly suitable for mobile refrigerators. However, the thermoelectric refrigerating refrigerator itself has the following disadvantages: such as having to be powered using a DC power supply; therefore, the AC/DC adapter is required to be configured when in use, and the cost is obviously increased.
In the prior art, as shown in fig. 1, an AC/DC switching power supply and a control board are usually used to control the supply voltage of the cooling fins to adjust the cooling power. Specifically, the switching power supply converts Alternating Current (AC) to a fixed Direct Current (DC) voltage, such as 12V, and supplies the same to the control board, which (e.g., via a DC/DC voltage reduction circuit provided thereon) can adjust, for example, the 12V DC voltage to different voltages to the cooling fins for controlling the temperature of the refrigerator. Such a solution would inevitably lead to higher electrical control costs.
Disclosure of Invention
The technical problem to be solved by the invention is how to reduce/save the electric control cost of the thermoelectric refrigeration refrigerator. Therefore, the invention provides a novel control circuit and a novel control method for a thermoelectric refrigeration refrigerator.
According to a first aspect of the present invention, there is provided a control circuit for a thermoelectric refrigeration refrigerator, comprising:
the output voltage of the output adjustable switching power supply is used for supplying power to a refrigerating sheet of the thermoelectric refrigeration refrigerator;
a control unit configured to receive an in-box temperature of the thermoelectric refrigerating refrigerator, a set temperature thereof, and an operating voltage currently supplied to the cooling fins, to generate and transmit a corresponding control signal according to the in-box temperature, the set temperature, and the operating voltage;
the output adjustable switching power supply comprises a voltage division sampling adjusting module for sampling an output voltage, wherein the voltage division sampling adjusting module is provided with a voltage division sampling end and is configured to receive and adjust voltage division according to a corresponding control signal sent by the control unit so as to generate a voltage at the voltage division sampling end;
the output adjustable switching power supply also comprises a voltage stabilizing module, a feedback module and a switch control module;
when the voltage at the divided voltage sampling end is less than the reference voltage provided in the voltage stabilization module, the feedback module is configured to feed back the comparison result to the switch control module, so as to control the increase of the output voltage through the switch control module until the voltage at the divided voltage sampling end is equal to the reference voltage;
when the voltage at the divided voltage sampling end is greater than the reference voltage provided in the voltage stabilizing module, the feedback module is configured to feed back the comparison result to the switch control module, so that the drop of the output voltage is controlled by the switch control module until the voltage at the divided voltage sampling end is equal to the reference voltage.
According to the control circuit of the thermoelectric refrigeration refrigerator, data parameters, namely the temperature in the refrigerator, the set temperature and the working voltage of the refrigerating sheet currently supplied to the thermoelectric refrigeration refrigerator, are collected through the control unit, and corresponding control signals are generated and sent to the switching power supply according to the related data parameters, so that the switching power supply can adjust the output voltage supplied to the refrigerating sheet according to the control signals, namely, the output adjustable switching power supply is formed to supply power to the refrigerating sheet; therefore, the traditional DC/DC voltage reduction circuit arranged on the control board in the prior art is not needed, so that the electric control cost of the thermoelectric refrigeration refrigerator is obviously reduced.
In addition, the control circuit of the thermoelectric refrigeration refrigerator according to the first aspect of the invention may also have the following additional technical features:
according to one aspect of the invention, according to a corresponding control signal sent by the control unit, the voltage division sampling adjustment module forms a voltage division resistor combination corresponding to the control signal to adjust voltage division so as to generate a voltage at the voltage division sampling end.
According to one aspect of the invention, the partial voltage sampling adjustment module comprises an NPN triode, a first partial voltage resistor, a second partial voltage resistor, a third partial voltage resistor, a fourth partial voltage resistor and a filter capacitor; the base electrode of the NPN triode is used for receiving the corresponding control signal generated and sent by the control unit; the first voltage-dividing resistor is connected in series with a second voltage-dividing resistor, one end of the first voltage-dividing resistor is connected to the output voltage end of the output adjustable switching power supply, one end of the second voltage-dividing resistor is grounded, the third voltage-dividing resistor is connected in series with a fourth voltage-dividing resistor, one end of the third voltage-dividing resistor is connected to the common connection end of the first voltage-dividing resistor and the second voltage-dividing resistor, and one end of the fourth voltage-dividing resistor is connected to the collector electrode of the NPN triode; the filter capacitor is connected between the common connection end of the third voltage dividing resistor and the fourth voltage dividing resistor and the ground; the common connecting end of the first voltage dividing resistor, the second voltage dividing resistor and the third voltage dividing resistor forms a voltage dividing and sampling end of the voltage dividing and sampling adjusting module.
According to an aspect of the invention, the voltage stabilizing module is a three-terminal regulator, wherein a reference input electrode of the three-terminal regulator is connected to a voltage dividing and sampling end of the voltage dividing and sampling adjusting module.
According to one aspect of the invention, the feedback module is an optocoupler, wherein the optocoupler includes a light emitting diode and a phototransistor at the high voltage main side of the power supply; the switch control module is a PWM control chip with a built-in switch MOSFET; wherein the anode of the light emitting diode is connected to the output voltage end of the output adjustable switching power supply through a current limiting resistor, and the cathode of the light emitting diode is connected to the cathode of the three-terminal regulator; and the emitter of the phototriode is connected to the control pin of the PWM control chip.
According to one aspect of the present invention, the control unit is a microcontroller configured to receive the inside temperature of the thermoelectric refrigeration refrigerator, the set temperature thereof, and the operating voltage currently supplied to the cooling fins, to generate and transmit a PWM signal having a corresponding duty ratio to the voltage division adoption adjusting module according to the inside temperature, the set temperature, and the operating voltage.
According to an aspect of the present invention, an output voltage terminal of the output adjustable switching power supply may be connected to an input terminal of a boost control circuit, an output voltage of the boost control circuit being used to power the remaining loads in the thermoelectric cooling refrigerator.
According to one aspect of the invention, the output voltage terminal of the boost control circuit is connected to the input terminal of a linear voltage stabilizing circuit, and the output voltage of the linear voltage stabilizing circuit is used for supplying power to the control unit.
According to one aspect of the invention, the output adjustable switching power supply and the control unit are both arranged on a control board of the thermoelectric refrigeration refrigerator.
According to a second aspect of the present invention, there is provided a control method of a thermoelectric refrigeration refrigerator, comprising the steps of:
s1, acquiring the temperature in the refrigerator, the set temperature and the working voltage of the refrigerating sheet currently supplied to the thermoelectric refrigerating refrigerator;
s2, generating corresponding control signals according to the temperature in the box, the set temperature and the working voltage data acquired in the step S1;
s3, sampling and voltage division adjusting the voltage output to the refrigeration piece according to the control signal generated in the step S2 to generate a divided voltage sampling voltage adjusted according to the control signal;
s4, comparing the divided sampled voltage generated in step S3 with a reference voltage, if the divided sampled voltage is smaller than the reference voltage, going to step S5, and if the divided sampled voltage is larger than the reference voltage, going to step S6;
s5, controlling the increase of the voltage output to the refrigeration piece until the divided sampling voltage is equal to the reference voltage;
and S6, controlling the voltage output to the refrigeration plate to drop until the divided sampling voltage is equal to the reference voltage.
Drawings
The invention will be further described with reference to the accompanying drawings and examples, in which:
FIG. 1 is a schematic diagram of a prior art control scheme for a thermoelectric refrigeration refrigerator;
FIG. 2 is a schematic block diagram of a control scheme for a thermoelectric refrigeration refrigerator having a control circuit according to a first aspect of the present invention;
FIG. 3 is a functional block diagram of a control circuit according to a first aspect of the present invention;
fig. 4 is a circuit diagram of an output adjustable switching power supply in a control circuit according to a first aspect of the present invention;
fig. 5 is a partial circuit diagram of a voltage stabilizing loop and a divided voltage sampling adjustment module (i.e., a sampling circuit) of the output adjustable switching power supply in the control circuit according to the first aspect of the present invention;
FIG. 6 is a functional block diagram according to one embodiment of a control scheme for a thermoelectric refrigeration refrigerator having a control circuit according to a first aspect of the present invention;
FIG. 7 is a circuit diagram of a portion of the functional blocks in the functional block diagram shown in FIG. 6;
fig. 8 is a flowchart of a control method of a thermoelectric cooling refrigerator in accordance with a second aspect of the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are illustrative and intended to explain the present invention and should not be construed as limiting the present invention.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings.
Referring to fig. 3 and 4, the voltage-dividing sampling adjustment module (i.e., the sampling circuit) of the output adjustable switching power supply 10 in the control circuit of the embodiment is basically mainly composed of an NPN transistor T17, first to fourth voltage-dividing resistors R19, R27, R76 and R77, and a filter capacitor E10, the voltage-stabilizing module in the voltage-stabilizing loop of the output adjustable switching power supply 10 is a three-terminal voltage stabilizer U4, the feedback module in the voltage-stabilizing loop of the output adjustable switching power supply 10 is an optocoupler U2, the switching control module is a PWM control chip U3 with a built-in switching MOSFET, and the control unit is a microcontroller 20.
The structure and connection relationship of relevant main modules in the control circuit according to the present invention are further described with reference to fig. 4 in conjunction with fig. 5. A pin 1, i.e., a base, of the NPN transistor T17 forms a receiving end of a control signal output by the microcontroller 20, for example, two resistors connected in series are connected in series between a control signal output end of the microcontroller 20 and a grounded pin 2, i.e., an emitter, of the NPN transistor T17, wherein the base of the NPN transistor T17 is connected to a common connection end of the two resistors; the first voltage-dividing resistor R19 is connected in series with the second voltage-dividing resistor R27, one end of the first voltage-dividing resistor R19 is connected to the output voltage VDD of the output adjustable switching power supply, one end of the second voltage-dividing resistor R27 is grounded, the third voltage-dividing resistor R76 is connected in series with the fourth voltage-dividing resistor R77, one end of the third voltage-dividing resistor R76 is connected to the common connection end of the first voltage-dividing resistor R19 and the second voltage-dividing resistor R27, and one end of the fourth voltage-dividing resistor R77 is connected to the pin 3, i.e., the collector, of the NPN transistor T17; wherein the filter capacitor E10 is connected between the common connection of the third voltage dividing resistor R76 and the fourth voltage dividing resistor R77 and ground; the common connection end of the first voltage-dividing resistor R19, the second voltage-dividing resistor R27 and the third voltage-dividing resistor R76 forms a voltage-dividing sampling end R. A pin 2 of the three-terminal voltage regulator U4, namely a reference input electrode, is connected to a voltage division sampling end R; the optocoupler U2 comprises a light emitting diode and a phototriode on the high-voltage main side of the power supply, a pin 1 of the optocoupler U2, namely an anode of the light emitting diode, is connected to an output voltage end VDD of the output adjustable switching power supply through a current-limiting resistor R18, a pin 2 of the optocoupler U2, namely a cathode of the light emitting diode, is connected to a pin 1 of the three-terminal regulator U4, namely a cathode; and a pin 3 of the optocoupler, i.e., an emitter of the phototransistor, is connected to a control pin C of the PWM control chip U3, and a switching MOSFET built in the PWM control chip U3 is used to control the operation of the power conversion circuit of the output adjustable switching power supply 10.
The specific operation principle of the embodiment of the control circuit shown in fig. 3 and 4 is:
the microcontroller 20 collects data, for example, the NTC sensor collects the internal temperature Tc of the thermoelectric refrigeration refrigerator, the operation panel collects the set temperature Ts, and the resistor samples the working voltage Vc currently supplied to the refrigeration plate 30 (i.e., the output voltage VDD currently supplied to the refrigeration plate), the microcontroller 20 further compares the internal temperature Tc and the set temperature Ts and determines whether the voltage supplied to the refrigeration plate 30 by the switching power supply 10 needs to be adjusted, and the microcontroller generates a PWM signal with a corresponding duty ratio according to the comparison and determination result; a base of an NPN transistor T17 of the voltage division sampling adjustment module (i.e., the sampling circuit) receives the PWM signal with the corresponding duty ratio, and after filtering through a capacitor E10, a first voltage division resistor R19, a second voltage division resistor R27, a third voltage division resistor R76, and a fourth voltage division resistor R77 form a voltage division resistor combination corresponding to the PWM signal with the corresponding duty ratio, and specifically, the second voltage division resistor R27, the third voltage division resistor R76, and the fourth voltage division resistor R77 form a combined voltage division resistor R77 according to the duty ratio of the PWM signalpwm:
And the combined voltage-dividing resistor RpwmThen, the voltage is serially connected to the first voltage dividing resistor R19 to sample and divide the output voltage VDD of the switching power supply 10, so as to obtain the voltage U at the divided voltage sampling end RR：
For example, when the microcontroller 20 compares the in-box temperature Tc with the set temperature Ts and determines that it is necessary to increase the voltage currently supplied to the cooling fins 30 by the switching power supply 10, it generates a PWM signal having an increased duty ratio; the base of the NPN transistor T17 of the voltage-dividing sampling adjustment module (i.e., the sampling circuit) receives the PWM signal with the increased duty ratio, and after filtering through the capacitor E10, the first voltage-dividing resistor R19, the second voltage-dividing resistor R27, the third voltage-dividing resistor R76, and the fourth voltage-dividing resistor R77 form a voltage-dividing resistor combination corresponding to the PWM signal with the increased duty ratio in the manner described above, and perform sampling and voltage-dividing adjustment on the output voltage VDD of the switching power supply 10, so as to obtain the voltage U at the voltage-dividing sampling end R (i.e., the reference input electrode of the three-terminal regulator U4, i.e., the pin 2)R(ii) a The voltage URWill be less than the reference voltage U provided in the three-terminal regulator U4Ref(e.g., 2.5V), the current of the light emitting diode (i.e., the sampling current I flowing through the light emitting diode and the three-terminal regulator as shown in fig. 5) passing through the optocoupler U2 is reduced, so that the light emitting intensity of the light emitting diode is reduced, the emitter current of the phototriode is reduced, the reduced current is fed back to the control pin C of the PWM control chip U3, the PWM control chip U3 correspondingly increases the PWM duty ratio of the switching MOSFET to adjust the operation of the power conversion circuit (e.g., the high frequency transformer), the voltage is converted to output different voltage waveforms, and the increased dc output voltage VDD is obtained through rectification filtering until the voltage U3REqual to the reference voltage URef(ii) a Thereby realizing the work of refrigerating sheetsThe voltage is controlled to be increased.
For example, when the microcontroller 20 compares the in-box temperature Tc with the set temperature Ts and determines that it is necessary to lower the voltage currently supplied to the cooling fins 30 by the switching power supply 10, it generates a PWM signal having a lowered duty ratio; the base of the NPN transistor T17 of the voltage-dividing sampling adjustment module (i.e., the sampling circuit) receives the PWM signal with the reduced duty ratio, and after filtering through the capacitor E10, the first voltage-dividing resistor R19, the second voltage-dividing resistor R27, the third voltage-dividing resistor R76, and the fourth voltage-dividing resistor R77 form a voltage-dividing resistor combination corresponding to the PWM signal with the reduced duty ratio in the manner described above, and perform sampling and voltage-dividing adjustment on the output voltage VDD of the switching power supply 10, so as to obtain the voltage U at the voltage-dividing sampling end R (i.e., the reference input electrode of the three-terminal regulator U4, i.e., the pin 2)R(ii) a The voltage URWill be greater than the reference voltage U provided in the three-terminal regulator U4Ref(e.g., 2.5V), the current of the light emitting diode (i.e., the sampling current I flowing through the light emitting diode and the three-terminal regulator as shown in fig. 5) passing through the optocoupler U2 is increased, so that the light emitting intensity of the light emitting diode is enhanced, the emitter current of the phototransistor is increased, the increased current is fed back to the control pin C of the PWM control chip U3, the PWM control chip U3 correspondingly reduces the PWM duty ratio of the switching MOSFET to adjust the operation of the power conversion circuit (e.g., the high frequency transformer), the voltage is converted to output different voltage waveforms, and the reduced dc output voltage VDD is obtained by rectification and filtering until the voltage U3REqual to the reference voltage URef(ii) a Thereby realizing the drop control of the working voltage of the refrigeration piece.
For example, when the microcontroller 20 compares the in-box temperature Tc with the set temperature Ts and determines that the voltage currently supplied to the cooling fins 30 by the switching power supply 10 can be maintained, it may maintain the PWM signal of the current duty ratio such that the voltage URMaintaining a reference voltage equal to that provided in the three terminal regulator; therefore, the maintenance control of the working voltage of the refrigeration piece is realized.
According to the control circuit of the embodiment, the temperature in the box is controlled by the microcontrollerTc is compared with the set temperature Ts, and whether the voltage currently supplied to the refrigerating sheet by the switching power supply needs to be increased, decreased or maintained is judged according to the comparison result to generate a PWM signal with a corresponding duty ratio, so that the voltage dividing resistors in the voltage dividing sampling adjusting module of the switching power supply can form a voltage dividing resistor combination corresponding to the duty ratio according to the corresponding duty ratio to generate a voltage U at a correspondingly adjusted voltage dividing sampling end (which can be considered to form an output voltage adjusting control end to a certain extent)RAccording to the voltage URThe output voltage supplied to the refrigerating sheet by the switching power supply is adjusted, so that an output adjustable switching power supply is formed to supply power to the refrigerating sheet; thereby eliminating the need for the prior art conventional DC/DC voltage reduction circuit provided on the control board, enabling control of the thermoelectric refrigeration refrigerator in a more cost effective and efficient manner.
The specific operating principle of the control circuit according to the invention is further explained below with reference to a set of illustrative examples:
in this example, the voltage output of the switching power supply 10 can be adjusted to, for example, 5.5 to 12V, and the microcontroller 20 collects the current inside temperature Tc, the set temperature Ts, and the refrigerating sheet operating voltage Vc in real time, aiming to control the inside temperature Tc within the range of [ Ts-0.5 ℃, Ts +0.5 ℃ ].
For example, when the microcontroller 20 compares the internal temperature Tc with the set temperature Ts to obtain Tc ≧ Ts +0.5 ℃, if the current working voltage Vc is zero (i.e., in a shutdown state), the microcontroller may send a PWM signal with a corresponding duty ratio, for example, the PWM signal with a 38% duty ratio makes a voltage dividing resistor with a corresponding set resistance in a voltage dividing sampling adjustment module form a voltage dividing resistor combination according to the duty ratio to generate a voltage UR at a correspondingly adjusted voltage dividing sampling end, and controls to increase the output voltage VDD supplied from the switching power supply to the refrigeration sheet to 8V according to the voltage UR, and if the internal temperature in the refrigerator does not reach the target range after running for ten minutes, the microcontroller may send a PWM signal with an increased duty ratio, for example, the PWM signal with a 100% duty ratio makes a voltage dividing resistor with a corresponding set resistance in the voltage dividing sampling adjustment module form a voltage dividing resistor combination according to the duty ratio (i.e., R76 ≧ Ts) R77 is connected in series, then connected in parallel with R27 and then connected in series with R19) to generate a voltage UR at the divided voltage sampling end after corresponding adjustment, and the output voltage VDD supplied to the refrigerating sheet by the switching power supply is increased to the full voltage of 12V according to the voltage UR to generate the maximum refrigerating capacity and the fastest refrigerating speed; and if the acquired current working voltage Vc is not zero (namely is not in a shutdown state), the microcontroller increases the duty ratio of the current PWM signal to 100% to control the increase of the output voltage VDD supplied to the refrigerating sheet by the switching power supply to the full voltage 12V, so that the maximum refrigerating capacity and the fastest refrigerating speed are generated.
When the microcontroller 20 compares the temperature Tc in the box with the set temperature Ts and obtains that the Tc is more than or equal to Ts and more than or equal to 0.5 ℃ and less than Ts +0.5 ℃, fuzzy PID adjustment can be adopted; if the temperature Tc in the refrigerator is decreased, the microcontroller sends a PWM signal with a decreased duty ratio to control to decrease the output voltage VDD supplied from the switching power supply to the cooling fins, and if the temperature Tc in the refrigerator is increased, the microcontroller sends a PWM signal with an increased duty ratio to control to increase the output voltage VDD supplied from the switching power supply to the cooling fins until the temperature Tc in the refrigerator is stabilized. During which the fluctuation of the temperature in the cabinet can be guaranteed to be minimal by using PID regulation.
When the microcontroller 20 compares the temperature Tc in the box with the set temperature Ts and obtains Tc<At Ts-0.5 ℃, the microcontroller may send a PWM signal with a duty cycle of 0 so that the voltage dividing resistors with corresponding set resistance values in the voltage dividing sampling adjustment module form a voltage dividing resistor combination according to the duty cycle (i.e., only R27 is connected in series with R19) to generate a voltage U at the voltage dividing sampling end after corresponding adjustmentRAnd according to the voltage URThe output voltage VDD supplied to the refrigerating sheet by the switch power supply is controlled to be reduced to the lowest voltage of 5.5V, or the refrigerating sheet is directly controlled to be turned off (namely Vc is zero) so as to be in a shutdown state.
Additionally or alternatively, in an alternative implementation of this exemplary example of the control circuit, the output voltage VDD supplied by the switching power supply to the cooling fins may be controlled by the duty cycle of the PWM signal sent by the microcontroller to be adjusted stepwise (i.e., to increase or decrease in steps) to avoid, to some extent, excessive fluctuations in the voltage across the cooling fins. For example, when Tc ≧ Ts +0.5 ℃ is collected, the microcontroller may increase the duty ratio of the current PWM signal to control the output voltage VDD supplied by the switching power supply to the refrigeration chip to increase by 0.5V and maintain the duty ratio for a certain period (e.g., one minute), while if Tc ≧ Ts +0.5 ℃ is still collected, the microcontroller may further increase the duty ratio of the PWM signal to control the output voltage VDD supplied by the switching power supply to the refrigeration chip to increase by 0.5V and maintain the duty ratio for a certain period (e.g., one minute), and so on until Ts-0.5 ≦ Tc < Ts +0.5 ℃ is collected. When Ts-0.5 ℃ is more than or equal to Tc and less than Ts +0.5 ℃, if the temperature Tc in the refrigerator is reduced, the microcontroller can reduce the duty ratio of the current PWM signal to control the output voltage VDD supplied to the refrigerating sheet by the switching power supply to be reduced by 0.5V and maintain the duty ratio for a certain period (such as one minute), and if the temperature Tc in the refrigerator is still reduced, the microcontroller can further reduce the duty ratio of the PWM signal to control the output voltage VDD supplied to the refrigerating sheet by the switching power supply to be reduced by 0.5V and maintain the duty ratio for a certain period (such as one minute); if the temperature Tc in the box rises (caused by opening a door of the box or putting new contents in the box), the microcontroller sends a PWM signal with an increased duty ratio to control the output voltage VDD supplied by the switching power supply to the cooling fins to rise by 0.5V; whereby the adjustment is performed stepwise until the inside temperature Tc is stabilized. However, it should be understood that the above-described voltage adjustment steps and sustain periods are merely illustrative, and any other feasible voltage adjustment steps and sustain periods may be used.
In one embodiment of the control scheme of the thermoelectric refrigeration refrigerator having the control circuit according to the first aspect shown in fig. 6 and 7, the output voltage terminal of the output adjustable switching power supply 10 may be further connected to the input terminal of the boost control circuit 40. Specifically, the Boost control circuit 40 includes a first inductor L1 and a Boost chip U7(Boost circuit) for energy storage, so that the adjustable (variable) output voltage of the switching power supply 10 can be stabilized at 12V via the Boost control circuit (i.e., the Boost control circuit stably outputs 12V voltage), thereby enabling power supply to the rest of the loads in the thermoelectric cooling refrigerator. The remaining loads may be considered to refer to loads of the refrigerator other than the cooling fins, such as interior lights or fans, etc., in the refrigerator. This ensures that the switching power supply can adjust the voltage output to the refrigeration sheet according to the collected data parameters and can also be matched with the boost control circuit to realize stable and reliable operation of other loads in the refrigerator. In addition, the output voltage terminal of the boost control circuit 40 may be further connected to the input terminal of the linear voltage stabilizing circuit 50. Specifically, the linear voltage regulating circuit 50 includes a linear voltage regulating chip U1, so that the 12V voltage stably output by the boost control circuit 10 can be stepped down and stabilized at 5V via the linear voltage regulating circuit (i.e. the linear voltage regulating circuit stably outputs 5V voltage), thereby realizing power supply for a control unit (e.g. a microcontroller). The switching power supply can adjust the voltage output to the refrigerating sheet according to the collected data parameters, and meanwhile, the switching power supply can be matched with the boost control circuit to realize stable and reliable work of other loads in the refrigerator and can be matched with the linear voltage stabilizing circuit to realize stable and reliable work of the microcontroller. In other words, there is no interplay between the variable supply to the cooling fins, the 12V stable supply to the rest of the load of the refrigerator and the 5V stable supply to the microcontroller.
Additionally or alternatively, the output adjustable switching power supply 10 may be incorporated with a control board 60 of the thermoelectric refrigeration refrigerator, as shown, for example, in FIG. 2. Specifically, the switching power supply 10 and the control unit, such as the microcontroller 20, are both disposed on the control board 60 of the thermoelectric refrigeration refrigerator, so that the control circuit can be installed by installing the control board 60, thereby avoiding the need for externally connecting the control board to the switching power supply.
Alternatively, in an optional embodiment of the control circuit of the present invention, the NPN transistor in the divided-voltage sampling adjustment module may be a band-stop transistor. Alternatively, in another alternative embodiment (not shown) of the control circuit of the present invention, the NPN transistor in the divided voltage sampling adjustment module may be replaced by an NMOS transistor, for example.
There is also provided according to a second aspect of the present invention a control method comprising:
firstly, in step S1, acquiring an inside temperature Tc of the thermoelectric cooling refrigerator, a set temperature Ts thereof, and an operating voltage Vc of a cooling fin currently supplied to the thermoelectric cooling refrigerator; for example, the temperature Tc in the box can be acquired through an NTC sensor, the set temperature Ts can be acquired through an operation panel, and the working voltage Vc can be acquired through resistance sampling;
subsequently, in step S2, generating a corresponding control signal according to the acquired data of the internal temperature Tc, the set temperature Ts and the operating voltage Vc; for example, the in-box temperature Tc and the set temperature Ts are compared and it is determined whether the adjustment of the operating voltage Vc is necessary, so that a control signal such as a PWM signal having a corresponding duty ratio can be generated according to the comparison and determination result;
subsequently, in step S3, the voltage output to the cooling plate is sampled and voltage-divided and adjusted according to the generated control signal, such as PWM signal with corresponding duty ratio, to generate a divided voltage sampled voltage U adjusted according to the control signal, such as duty ratio of the control signalR；
Subsequently, in step S4, the generated divided sampling voltages U are comparedRAnd a reference voltage URefIf the voltage is divided, the sampling voltage URIs less than the reference voltage URefGo to step S5, if the divided sampling voltage U isRGreater than the reference voltage URefGo to step S6;
in step S5, the voltage output to the cooling plate is controlled to increase until the divided sampling voltage U is obtainedRIs equal to the reference voltage URefFor controlling the in-tank temperature Tc;
s6, controlling the voltage output to the refrigerating sheet to drop until the divided sampling voltage U is obtainedRIs equal to the reference voltage URefFor controlling the in-tank temperature Tc.
In the description of the invention, it is to be understood that the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Thus, the definitions of "first", "second", "third" and "fourth" features may explicitly or implicitly include one or more of such features.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and those skilled in the art can make combinations, changes, modifications, substitutions and alterations to the above embodiments within the scope of the present invention.
Claims (10)
1. A control circuit of a thermoelectric refrigeration refrigerator is used for driving the thermoelectric refrigeration refrigerator, and is characterized by comprising the following components:
the output adjustable switching power supply is used for supplying power to the refrigerating sheet of the thermoelectric refrigerating refrigerator;
a control unit configured to receive an in-box temperature of the thermoelectric refrigerating refrigerator, a set temperature thereof, and an operating voltage currently supplied to the cooling fins, to generate and transmit a corresponding control signal according to the in-box temperature, the set temperature, and the operating voltage;
the output adjustable switching power supply comprises a voltage division sampling adjusting module for sampling an output voltage, wherein the voltage division sampling adjusting module is provided with a voltage division sampling end and is configured to receive and adjust voltage division according to a corresponding control signal sent by the control unit so as to generate a voltage at the voltage division sampling end;
the output adjustable switching power supply also comprises a voltage stabilizing module, a feedback module and a switch control module;
when the voltage at the divided voltage sampling end is less than the reference voltage provided in the voltage stabilization module, the feedback module is configured to feed back the comparison result to the switch control module, so as to control the increase of the output voltage through the switch control module until the voltage at the divided voltage sampling end is equal to the reference voltage;
when the voltage at the divided voltage sampling end is greater than the reference voltage provided in the voltage stabilizing module, the feedback module is configured to feed back the comparison result to the switch control module, so that the drop of the output voltage is controlled by the switch control module until the voltage at the divided voltage sampling end is equal to the reference voltage.
2. The control circuit of the thermoelectric refrigerator-freezer according to claim 1, wherein the voltage dividing sampling adjusting module forms a voltage dividing resistor combination corresponding to the control signal to adjust the voltage division according to the corresponding control signal sent by the control unit, so as to generate the voltage at the voltage dividing sampling end.
3. The control circuit of the thermoelectric refrigerating refrigerator as claimed in claim 1 or 2, wherein the voltage division sampling adjusting module comprises an NPN triode, a first voltage division resistor, a second voltage division resistor, a third voltage division resistor, a fourth voltage division resistor, and a filter capacitor; the base electrode of the NPN triode is used for receiving the corresponding control signal generated and sent by the control unit; the first voltage-dividing resistor is connected in series with a second voltage-dividing resistor, one end of the first voltage-dividing resistor is connected to the output voltage end of the output adjustable switching power supply, one end of the second voltage-dividing resistor is grounded, the third voltage-dividing resistor is connected in series with a fourth voltage-dividing resistor, one end of the third voltage-dividing resistor is connected to the common connection end of the first voltage-dividing resistor and the second voltage-dividing resistor, and one end of the fourth voltage-dividing resistor is connected to the collector of the NPN triode; the filter capacitor is connected between the common connection end of the third voltage dividing resistor and the fourth voltage dividing resistor and the ground; the common connecting end of the first voltage dividing resistor, the second voltage dividing resistor and the third voltage dividing resistor forms a voltage dividing and sampling end of the voltage dividing and sampling adjusting module.
4. The control circuit of the thermoelectric refrigerating refrigerator as claimed in claim 1 or 2, wherein the voltage stabilizing module is a three-terminal regulator, wherein a reference input electrode of the three-terminal regulator is connected to the voltage division sampling terminal of the voltage division sampling adjusting module.
5. The control circuit of the thermoelectric refrigerator according to claim 4, wherein the feedback module is an optocoupler, wherein the optocoupler includes a light emitting diode and a phototransistor at the high voltage main side of the power supply; the switch control module is a PWM control chip with a built-in switch MOSFET;
wherein the anode of the light emitting diode is connected to the output voltage end of the output adjustable switching power supply through a current limiting resistor, and the cathode of the light emitting diode is connected to the cathode of the three-terminal regulator; and the emitter of the phototriode is connected to the control pin of the PWM control chip.
6. The control circuit of the thermoelectric refrigerating refrigerator according to claim 1 or 2, wherein the control unit is a microcontroller configured to receive an in-box temperature of the thermoelectric refrigerating refrigerator, a set temperature thereof, and an operating voltage currently supplied to the cooling fins, to generate and transmit a PWM signal having a corresponding duty ratio to the voltage division adoption adjusting module according to the in-box temperature, the set temperature, and the operating voltage.
7. The control circuit of the thermoelectric refrigerating refrigerator as claimed in claim 1 or 2, wherein the output voltage terminal of the output adjustable switching power supply is connected to the input terminal of the boost control circuit, and the output voltage of the boost control circuit is used for supplying power to the rest of the loads in the thermoelectric refrigerating refrigerator.
8. The control circuit of the thermoelectric refrigerator-freezer according to claim 7, wherein the output voltage terminal of the boost control circuit is connected to the input terminal of a linear voltage regulator circuit, the output voltage of the linear voltage regulator circuit being used to power the control unit.
9. The control circuit of the thermoelectric refrigerator according to claim 1 or 2, wherein the output adjustable switching power supply and the control unit are disposed on a control board of the thermoelectric refrigerator.
10. A control method of a thermoelectric refrigeration refrigerator comprises the following steps:
s1, acquiring the temperature in the refrigerator, the set temperature and the working voltage of the refrigerating sheet currently supplied to the thermoelectric refrigerating refrigerator;
s2, generating corresponding control signals according to the temperature in the box, the set temperature and the working voltage data acquired in the step S1;
s3, sampling and voltage division adjusting the voltage output to the refrigeration piece according to the control signal generated in the step S2 to generate a divided voltage sampling voltage adjusted according to the control signal;
s4, comparing the divided sampled voltage generated in step S3 with a reference voltage, if the divided sampled voltage is smaller than the reference voltage, going to step S5, and if the divided sampled voltage is larger than the reference voltage, going to step S6;
s5, controlling the increase of the voltage output to the refrigeration piece until the divided sampling voltage is equal to the reference voltage;
and S6, controlling the voltage output to the refrigeration plate to drop until the divided sampling voltage is equal to the reference voltage.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011305123.8A CN114517990A (en) | 2020-11-19 | 2020-11-19 | Control circuit and method for thermoelectric refrigeration refrigerator |
| PCT/CN2021/131639 WO2022105851A1 (en) | 2020-11-19 | 2021-11-19 | Control circuit for thermoelectric refrigeration refrigerator, and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011305123.8A CN114517990A (en) | 2020-11-19 | 2020-11-19 | Control circuit and method for thermoelectric refrigeration refrigerator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114517990A true CN114517990A (en) | 2022-05-20 |
Family
ID=81595149
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011305123.8A Pending CN114517990A (en) | 2020-11-19 | 2020-11-19 | Control circuit and method for thermoelectric refrigeration refrigerator |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN114517990A (en) |
| WO (1) | WO2022105851A1 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86107077A (en) * | 1986-10-06 | 1987-08-26 | 孟祥厚 | Electronic control circuit for refrigerating compressor |
| CN87105169A (en) * | 1987-07-22 | 1988-04-27 | 孟祥厚 | Electronic control circuit for refrigerator |
| US5841204A (en) * | 1997-03-21 | 1998-11-24 | English; Larry G. | Temperature control system and method |
| CN2383267Y (en) * | 1999-04-12 | 2000-06-14 | 黄万江 | Intelligent switch power source of semiconductor refrigerator |
| CN2456117Y (en) * | 2000-12-28 | 2001-10-24 | 上海纽福克斯汽车配件有限公司 | Universal electric refrigerator |
| CN2831203Y (en) * | 2005-09-10 | 2006-10-25 | 海尔集团公司 | Semiconductor refrigerator |
| CN107588576A (en) * | 2017-08-21 | 2018-01-16 | 上海空间电源研究所 | The thermoelectric cooling power optimization regulating system and method for high precision temperature control |
-
2020
- 2020-11-19 CN CN202011305123.8A patent/CN114517990A/en active Pending
-
2021
- 2021-11-19 WO PCT/CN2021/131639 patent/WO2022105851A1/en active Application Filing
Also Published As
| Publication number | Publication date |
|---|---|
| WO2022105851A1 (en) | 2022-05-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11653431B2 (en) | Load control device for a light-emitting diode light source | |
| US20080304299A1 (en) | Low voltage LED drive from 120VAC line | |
| US10694593B2 (en) | Dynamic power supply for light emitting diode | |
| CN110536506B (en) | LED stroboscopic flashing circuit | |
| CN108617055B (en) | LED drive circuit and drive method of LED load | |
| CN108430139B (en) | LED driving circuit with silicon controlled rectifier dimmer and control method thereof | |
| CN114517990A (en) | Control circuit and method for thermoelectric refrigeration refrigerator | |
| US11258298B2 (en) | Solar powered office and factory lighting | |
| WO2016071146A1 (en) | Linear post-regulator | |
| CN110118422B (en) | Air conditioning system and operation method thereof | |
| CN204539556U (en) | The switch dimming drive circuit of Width funtion LED and LED dimming control system | |
| CN208793296U (en) | A kind of speed regulation circuit for fan | |
| KR100281352B1 (en) | Refrigerator | |
| CN112803568B (en) | AC/DC power supply system and power supply method | |
| CN213402821U (en) | Switching power supply voltage stabilizer circuit and air conditioner | |
| US11457516B2 (en) | Driver arrangement for a LED lighting device, a lighting device using the same and a drive method | |
| CN216721628U (en) | Low-power-consumption power supply circuit | |
| CN219893483U (en) | Low-cost LED constant current drive circuit | |
| RU2009132617A (en) | SUB-SYSTEM OF ELECTRIC SUPPLY OF THE REFRIGERATING CHAMBER OR THE COOLED SPACE, METHOD FOR PREVENTING THE SPEED OF THE COMPRESSOR OF THE TRANSPORT COLD REFRIGERATOR UNIT | |
| CN118054663A (en) | Multi-module power supply loop for supplying power to internal equipment of air conditioner | |
| EP3592111A1 (en) | A driver arrangement for a led lighting device, a lighting device using the same and a drive method | |
| CN111315101A (en) | Lighting board and lamp with same | |
| CN117997112A (en) | Power supply circuit and switching power supply using same | |
| CN116847500A (en) | LED constant current driving system | |
| CN110753425A (en) | Circuit for extracting low voltage from inductor and supplying power to chip |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |