Control method based on cold and heat treatment system

Abstract

The invention discloses a control method based on a cold and heat treatment system. The cold and heat treatment system adopts an H-bridge module to switch the polarity of an input port of a thermoelectric refrigerating unit so as to control switching of a heating mode and a refrigerating mode; refrigerating and heating power is controlled through pulse modulation; the heat dissipation of the thermoelectric refrigerating unit passes through the radiator temperature acquisition and the radiator; a plurality of channels share the H-bridge module to realize refrigeration and heating switching, and control on temperature influence is realized through secondary modulation of a relay during working; the output temperature of the terminal thermoelectric refrigerating unit is monitored in real time, heat dissipation is achieved by controlling the power of the heat dissipation fan, the refrigerating and heating power is controlled by modulating the voltage pulse of the refrigerating sheet for simultaneous working of multiple channels, and the energy requirements in different channels are met through secondary modulation of the relays arranged in the channels. And multi-channel differential accurate temperature control is achieved.

Description

Technical Field

[0001] This invention relates to the field of physiotherapy system control methods, specifically to a control method based on a cold and hot therapy system. Background Technology

[0002] Patent CN202211105019.3 discloses a skin treatment device, comprising: a skin contact element; a semiconductor cooling element, one side of which is thermally coupled to the skin contact element; a first driving circuit having a control terminal and a first output terminal and a second output terminal electrically connected to the semiconductor cooling element; a control circuit electrically connected to the control terminal, and controlling the first driving circuit by issuing a first control signal and a second control signal at different times. The first control signal is used to make the first output terminal output a positive voltage and the second output terminal output a negative voltage, so as to cool the side of the semiconductor cooling element thermally coupled to the skin contact element; the second control signal is used to make the first output terminal output a negative voltage and the second output terminal output a positive voltage, so as to heat the side of the semiconductor cooling element thermally coupled to the skin contact element. This method achieves the cooling / heating effect of the semiconductor cooling element by changing the voltage polarity on both sides of the semiconductor cooling element. Furthermore, a sensor detects data such as ambient temperature, skin temperature, and voltage / current of the working circuit, causing the control circuit to output control signals, namely the first control signal and the second control signal, to drive the H-bridge to switch polarities.

[0003] The hardware design of this system is suitable for controlling the temperature of a single-channel semiconductor cooling / heating system. However, it cannot achieve differentiated temperature control of each channel in a multi-channel semiconductor cooling / heating system, making it unsuitable for precise differential temperature control of multiple channels.

[0004] The lack of power monitoring for the thermoelectric cooler can easily lead to damage; the use of a threshold comparison method for driving the H-bridge with a temperature-converted signal poses a risk of overtreatment. Summary of the Invention

[0005] The purpose of this invention is to provide a control method based on a cold and hot therapy system to solve the problem mentioned in the background art that existing therapy systems cannot achieve multi-channel differential temperature control.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A control method based on a cold and hot therapy system is disclosed. The cold and hot therapy system uses an H-bridge module to switch the polarity of the thermoelectric cooler input port to control the switching of heating and cooling modes; the cooling and heating power is controlled by pulse modulation; the heat dissipation of the thermoelectric cooler is achieved through radiator temperature acquisition and radiator; multiple channels share the H-bridge module to realize the switching of cooling and heating, and the temperature influence is controlled by relay secondary modulation during operation.

[0008] The switching between the cold and hot modes of the system is achieved by switching the polarity of the output port of the electric heating cooler driven by the H-bridge module, which is realized by changing the voltage levels of IN1 and IN2 at the cooling chip terminals.

[0009] Controlling the heat dissipation capacity of the thermoelectric cooler first requires analyzing the working principle of the thermoelectric cooler and performing quantitative analysis, including the following steps;

[0010] S1; The thermoelectric cooler is a refrigeration technology that utilizes the Seebeck effect, Peltier effect, Thomson effect, Joule effect, and Fourier effect. Its refrigeration performance depends on these five basic thermoelectric effects.

[0011] S2; The Seebeck effect generates an electromotive force when there is a temperature difference between the two ends of different materials, and the Peltier effect causes heat absorption and release phenomena when current passes through a closed loop formed by different materials.

[0012] S3; The relationship between Peltier heat and electric current generated by the Peltier effect, Q P =π AB ×I; where π AB The Peltier coefficient (determined by material A / B), I is the current, and the Joule heating phenomenon, i.e., the heat generated inside a current-carrying conductor, is expressed as Q. J =I 2 R, where Q J The Joule heating effect, where I is the electric current and R is the conductor resistance, is an irreversible thermal effect. The Thomson effect, on the other hand, is a reversible thermal effect, where a temperature gradient exists in the direction of the current flow in a current-carrying conductor, causing heat exchange between the conductor and its surroundings.

[0013] S4; The Fourier effect mainly describes the heat transfer along a temperature gradient in a medium. The heat transferred per unit time is directly proportional to the area perpendicular to the heat transfer and the temperature gradient. Where λ is the thermal conductivity of the medium, K is the thermal conductivity coefficient of the medium, and T h T is the absolute temperature of the hot end. c This is the absolute temperature of the cold end.

[0014] S5; Since the Thomson heat is very small and negligible, Q can be obtained through energy conservation. H =Q P +Q J +QK The quantitative expression for the heat exchange between the cold end of a semiconductor refrigeration chip and the outside environment is:

[0015] S6; then the cooling capacity within the treatment time t; The change function of factor KΔT over the treatment time will affect the total cooling capacity Q. H Furthermore, KΔT = K × (T) h -T c The smaller the factor KΔT, the greater its cooling capacity Q. H The larger T is. c The absolute temperature of the cold junction is usually negative, T h The absolute temperature of the hot end is usually a positive value; therefore, T h The smaller the absolute temperature of the hot end, the smaller the factor KΔT, and the smaller the cooling capacity Q. H The larger.

[0016] The heat dissipation of the thermoelectric cooler includes the following steps;

[0017] S1; The system hardware temperature acquisition device acquires the hot end temperature and feeds it back to the MCU main controller;

[0018] S2; temperature control is achieved through a MIMO neural network temperature control algorithm;

[0019] S3; Drives the fan module; Controls fan power; Controls the absolute temperature of the hot end Th; Thus controlling the total cooling capacity QH;

[0020] S4; The fan power control changes the heat dissipation energy of the cooling chip, thus changing the absolute temperature Th at the hot end. The system then collects the hot end temperature and feeds it back to the main controller.

[0021] By repeating the above steps, different heat dissipation methods can be implemented under different environments, achieving precise temperature control.

[0022] The H-bridge module circuit has I / O_1 and I / O_2 as output ports, and OUT1 and OUT2 as output ports. The branch lines connected to port OUT1 are combined into the OUT1 bus, and the branch lines connected to port OUT2 are combined into the OUT2 bus. The treatment terminal has multiple channels, each containing a relay. The control coil of each relay is controlled by the MUC. The relay contacts of each channel are normally open, and the contacts close after receiving a control signal. Each channel relay has at least two contacts, one of which, contact-1, is connected to the OUT1 bus, and the other, contact-2, is connected to the OUT2 bus. When the relay of each channel receives the relay coil control signal, it applies the terminal voltage formed by OUT1 and OUT2 to the input port of the cooling chip of each channel through the aforementioned contacts-1 and-2 of each relay.

[0023] The H-bridge input ports I / O_1 and I / O_2 are pulse width modulated (PWM) to achieve pulse modulation on the port voltage between output ports OUT1 and OUT2. By controlling the opening and closing timing of the relays in each channel, different energy supplies are provided to different channels of the treatment terminal that share the H-bridge output port. The secondary modulation of the relays in each channel of the treatment terminal is adapted to the cooling and heating requirements of the heat flux density applied to different treatment positions of each channel. Thus, when multiple channels of the treatment terminal work simultaneously, the treatment temperature can be met at different treatment positions within the same treatment time, achieving a uniform and good treatment effect.

[0024] Given the varying heat flux densities at different treatment sites, multi-channel operation utilizes relay-based secondary modulation to control temperature. Furthermore, the secondary modulation of relays can also eliminate the influence of factors affecting temperature, such as differences in materials and processes used in each channel, and the assembly of heat dissipation mechanisms.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] This invention achieves heat dissipation by real-time monitoring of the output temperature of the terminal thermoelectric cooler and controlling the power of the heat-dissipating fan. For multiple channels working simultaneously, the cooling and heating power is controlled by voltage pulse modulation at the cooling chip end. The energy demand of different channels is achieved through secondary modulation by relays set in the channels, thus achieving precise temperature control for multiple channels. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the circuit structure of the present invention;

[0028] Figure 2 This is a diagram of the H-bridge drive circuit of the present invention;

[0029] Figure 3 This is a schematic diagram of the hot-end temperature control of the cooling chip of the present invention;

[0030] Figure 4 This is a schematic diagram of the relay secondary modulation circuit of the present invention;

[0031] Figure 5 This is a schematic diagram of the pulse modulation timing of the present invention;

[0032] Figure 6 This is a schematic diagram of the relay secondary modulation timing of the present invention;

[0033] Figure 7 This is a schematic diagram of the heat transfer model of the semiconductor refrigeration chip of the present invention;

[0034] Figure 8 This is a schematic diagram illustrating the Peltier effect principle of the present invention;

[0035] Figure 9 This is a schematic diagram illustrating the Thomson effect principle of the present invention. Detailed Implementation

[0036] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0037] A control method based on a cold and hot therapy system is disclosed. The cold and hot therapy system uses an H-bridge module to switch the polarity of the thermoelectric cooler input port to control the switching of heating and cooling modes; the cooling and heating power is controlled by pulse modulation; the heat dissipation of the thermoelectric cooler is achieved through radiator temperature acquisition and radiator; multiple channels share the H-bridge module to realize the switching of cooling and heating, and the temperature influence is controlled by relay secondary modulation during operation.

[0038] The switching between the cold and hot modes of the system is achieved by switching the polarity of the output port of the electric heating cooler through the H-bridge module, which is accomplished by changing the voltage levels of IN1 and IN2 at the cooling chip terminals.

[0039] like Figure 7-9 As shown, controlling the heat dissipation capacity of the thermoelectric cooler first requires analyzing the working principle of the thermoelectric cooler and performing quantitative analysis, including the following steps;

[0040] S1; The thermoelectric cooler is a refrigeration technology that utilizes the Seebeck effect, Peltier effect, Thomson effect, Joule effect, and Fourier effect. Its refrigeration performance depends on these five basic thermoelectric effects.

[0041] S2; The Seebeck effect generates an electromotive force when there is a temperature difference between the two ends of different materials, and the Peltier effect causes heat absorption and release phenomena when current passes through a closed loop formed by different materials.

[0042] S3; The relationship between Peltier heat and electric current generated by the Peltier effect, Q P =π AB ×I; where π AB The Peltier coefficient (determined by material A / B), I is the current, and the Joule heating phenomenon, i.e., the heat generated inside a current-carrying conductor, is expressed as Q. J =I 2 R, where Q J The Joule heating effect, where I is the electric current and R is the conductor resistance, is an irreversible thermal effect. The Thomson effect, on the other hand, is a reversible thermal effect, where a temperature gradient exists in the direction of the current flow in a current-carrying conductor, causing heat exchange between the conductor and its surroundings.

[0043] S4; The Fourier effect mainly describes the heat transfer along a temperature gradient in a medium. The heat transferred per unit time is directly proportional to the area perpendicular to the heat transfer and the temperature gradient. Where λ is the thermal conductivity of the medium, K is the thermal conductivity coefficient of the medium, and T h T is the absolute temperature of the hot end. c This is the absolute temperature of the cold end.

[0044] S5; Since the Thomson heat is very small and negligible, Q can be obtained through energy conservation. H =Q P +Q J +Q K The quantitative expression for the heat exchange between the cold end of a semiconductor refrigeration chip and the outside environment is:

[0045] S6; then the cooling capacity within the treatment time t; The change function of factor KΔT over the treatment time will affect the total cooling capacity Q. H Furthermore, KΔT = K × (T) h -T c The smaller the factor KΔT, the greater its cooling capacity Q. H The larger T is. c The absolute temperature of the cold junction is usually negative, T h The absolute temperature of the hot end is usually a positive value; therefore, T h The smaller the absolute temperature of the hot end, the smaller the factor KΔT, and the smaller the cooling capacity Q. H The larger.

[0046] like Figure 3 As shown, the heat dissipation of the thermoelectric cooler includes the following steps;

[0047] S1; The system hardware temperature acquisition device acquires the hot end temperature and feeds it back to the MCU main controller;

[0048] S2; temperature control is achieved through a MIMO neural network temperature control algorithm;

[0049] S3; Drive fan module; Control fan power; Control hot end absolute temperature T h Thus controlling the total cooling capacity Q H ;

[0050] S4; Fan power control alters the heat dissipation energy of the cooling chip, and the absolute temperature of the hot end T. h Upon the change, the system then collects the hot-end temperature and feeds it back to the main controller.

[0051] By repeating the above steps, different heat dissipation methods can be implemented under different environments, achieving precise temperature control.

[0052] like Figure 4 As shown, the H-bridge module circuit output ports are I / O_1 and I / O_2, and output ports are OUT1 and OUT2. The branch lines connected to port OUT1 are combined into the OUT1 bus, and the branch lines connected to port OUT2 are combined into the OUT2 bus. The treatment terminal has multiple channels, each containing a relay. The control coil of each relay is controlled by the MUC. The relay contacts of each channel are normally open, and the contacts close after receiving a control signal. Each channel relay has ≥2 contacts, one of which, contact-1, is connected to the OUT1 bus, and contact-2 is connected to the OUT2 bus. When the relay of each channel receives the relay coil control signal, it applies the terminal voltage formed by OUT1 and OUT2 to the input port of the cooling chip of each channel through the aforementioned contacts-1 and contact-2 of each relay.

[0053] like Figure 4 As shown, the H-bridge input ports I / O_1 and I / O_2 are pulse width modulated (PWM) to achieve pulse modulation on the port voltage between output ports OUT1 and OUT2. By controlling the opening and closing timing of the relays of each channel, different energy supplies are provided to different channels of the treatment terminal that share the H-bridge output port. The secondary modulation of the relays of each channel of the treatment terminal is adapted to the cooling and heating requirements of the heat flux density of each channel applied to different treatment positions. Thus, when multiple channels of the treatment terminal work simultaneously, the treatment temperature can be met at different treatment positions within the same treatment time, achieving a uniform and good treatment effect.

[0054] Given the varying heat flux densities at different treatment sites, multi-channel operation utilizes relay-based secondary modulation to control temperature. Furthermore, the secondary modulation of relays can also eliminate the influence of factors affecting temperature, such as differences in materials and processes used in each channel, and the assembly of heat dissipation mechanisms.

[0055] like Figure 2 As shown, the H-bridge hardware circuit is set on the thermoelectric cooler to control the polarity switching of the port voltage. The switching is achieved by changing the level of IN1 and IN2. The following situations occur during operation.

[0056] IN1 IN2 Current direction state H L VCC→Q1→OUT1→Refrigeration element→OUT2→Q4→Ground Refrigeration L L No-loop formation Not working L H VCC→Q2→OUT2→Refrigeration element→OUT1→Q3→Ground heating H H No-loop formation Not working

[0057] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the present invention without departing from its novel spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A control method based on a cold / heat therapy system, characterized in that, The cold and hot therapy system uses an H-bridge module to switch the polarity of the thermoelectric cooler input port to control the switching between heating and cooling modes; it controls the cooling and heating power through pulse modulation; the heat dissipation of the thermoelectric cooler is achieved through radiator temperature acquisition and radiator; multiple channels share the H-bridge module to realize the switching between cooling and heating, and the temperature influence is controlled through secondary modulation by relays during operation.

2. The control method based on a cold and hot therapy system according to claim 1, characterized in that, The switching between the cold and hot modes of the system is achieved by switching the polarity of the output port of the electric heating cooler through the H-bridge module, which is accomplished by changing the voltage levels of IN1 and IN2 at the cooling chip terminals.

3. The control method based on a cold and hot therapy system according to claim 1, characterized in that, Controlling the heat dissipation capacity of the thermoelectric cooler first requires analyzing the working principle of the thermoelectric cooler and performing quantitative analysis, including the following steps; S1; The thermoelectric cooler is a refrigeration technology that utilizes the Seebeck effect, Peltier effect, Thomson effect, Joule effect, and Fourier effect. Its refrigeration performance depends on these five basic thermoelectric effects. S2; The Seebeck effect generates an electromotive force when there is a temperature difference between the two ends of different materials, and the Peltier effect causes heat absorption and release phenomena when current passes through a closed loop formed by different materials. S3; The relationship between Peltier heat and electric current generated by the Peltier effect, Q P =π AB ×I; Joule heating, the phenomenon of heat generated inside an electric conductor, is expressed as Q. J =I 2 R is an irreversible thermal effect. The Thomson effect, where a temperature gradient exists in the direction of current flow in a current-carrying conductor, causes heat exchange between the conductor and its surroundings, is a reversible thermal effect. S4; The Fourier effect mainly describes the heat transfer along a temperature gradient, where the heat transferred per unit time is directly proportional to the area perpendicular to the temperature gradient. S5; Since the Thomson heat is very small and negligible, Q can be obtained through energy conservation. H =Q P +Q J +Q K The quantitative expression for the heat exchange between the cold end of a semiconductor refrigeration chip and the outside environment is: S6; then the cooling capacity within the treatment time t; The change function of factor KΔT over the treatment time will affect the total cooling capacity Q. H Furthermore, KAT = K × (T) h -T c The smaller the factor KΔT, the greater its cooling capacity Q. H The larger T is. c The absolute temperature of the cold junction is usually negative, T h The absolute temperature of the hot end is usually a positive value; therefore, T h The smaller the absolute temperature of the hot end, the smaller the factor KΔT, and the smaller the cooling capacity Q. H The larger.

4. The control method based on the cold and heat therapy system according to claim 3, characterized in that, The heat dissipation of the thermoelectric cooler includes the following steps; S1; The system hardware temperature acquisition device acquires the hot end temperature and feeds it back to the MCU main controller; S2; temperature control is achieved through a MIMO neural network temperature control algorithm; S3; Drive fan module; Control fan power; Control hot end absolute temperature T h Thus controlling the total cooling capacity Q H ; S4; Fan power control alters the heat dissipation energy of the cooling chip, and the absolute temperature of the hot end T. h Upon the change, the system then collects the hot-end temperature and feeds it back to the main controller. By repeating the above steps, different heat dissipation methods can be implemented under different environments, achieving precise temperature control.

5. The control method based on the cold and heat therapy system according to claim 2, characterized in that, The H-bridge module circuit has I / O_1 and I / O_2 as output ports, and OUT1 and OUT2 as output ports. The branch lines connected to port OUT1 are combined into the OUT1 bus, and the branch lines connected to port OUT2 are combined into the OUT2 bus. The treatment terminal has multiple channels, each containing a relay; the control coil of each relay is controlled by the MUC; the relay contacts of each channel are normally open, and close when a control signal is received; each channel relay has ≥2 contacts, one of which, contact-1, is connected to the OUT1 bus, and contact-2 is connected to the OUT2 bus; when each channel relay receives the relay coil control signal, it applies the terminal voltage formed by OUT1 and OUT2 to the input port of the cooling chip of each channel through the aforementioned contacts-1 and-2 of each relay.

6. The control method based on a cold and hot therapy system according to claim 5, characterized in that, The H-bridge input ports I / O_1 and I / O_2 are pulse width modulated (PWM) to achieve pulse modulation on the port voltage between the output ports OUT1 and OUT2. By controlling the opening and closing sequence of the relays in each channel, different energy supplies are provided to different channels of the treatment terminal that share the H-bridge output port. The secondary modulation of the relays in each channel of the treatment terminal is adapted to the cooling and heating requirements of the heat flux density applied to different treatment positions of each channel. Thus, when multiple channels of the treatment terminal work simultaneously, the treatment temperature can be met at different treatment positions within the same treatment time, achieving a uniform and good treatment effect.

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