Hydrogen atomic clock temperature control system

Abstract

The embodiment of the invention provides a hydrogen atomic clock temperature control system. The system comprises at least one temperature control subsystem, and the temperature control subsystem comprises a control module, a temperature detection module and a temperature adjusting module. The temperature detection module is arranged on the outer side of a microwave resonant cavity of the hydrogen atomic clock, and the temperature detection module is used for collecting the temperature of the microwave resonant cavity; the temperature adjusting module comprises a refrigerating unit and a heating unit; the refrigerating unit and the heating unit are arranged on the outer side of the microwave resonant cavity; the refrigeration unit is used for cooling the microwave resonant cavity; the heating unit is used for heating the microwave resonant cavity; the control module is electrically connected with the refrigeration unit, the heating unit and the temperature detection module. The control module is used for adjusting the temperature of the microwave resonant cavity through the refrigerating unit or the heating unit. According to the hydrogen atomic clock temperature control system provided by the embodiment of the invention, the limitation that an existing hydrogen atomic clock temperature control system only has a one-way heating function but lacks a refrigeration function is solved, and rapid adjustment and stable maintenance of the temperature are realized.

Description

Technical Field

[0001] The present invention relates to the field of temperature control technology, and in particular to a hydrogen atomic clock temperature control system. Background Art

[0002] The hydrogen maser clock is a high-precision timing device based on the frequency of hydrogen atom energy level transitions. With its ultra-high stability and accuracy, it plays a key role in fields such as satellite navigation, astronomical observation, quantum communication, and radio astronomy, which have extremely strict requirements on time accuracy.

[0003] Hydrogen atomic clocks have extremely high requirements for temperature environment. Their core components, such as microwave resonant cavities, need to operate within an extremely stable narrow temperature band. Existing technologies usually rely on active heating and passive heat dissipation for temperature control.

[0004] However, existing hydrogen atomic clocks have significant drawbacks when faced with ambient temperature fluctuations or internal thermal disturbances. They are unable to cope with rising temperatures, which significantly intensify the thermal motion of hydrogen atoms, directly causing energy level transition frequency drift and resulting in a decrease in timing accuracy. Summary of the Invention

[0005] An embodiment of the present invention provides a hydrogen atomic clock temperature control system to adjust the operating temperature of the hydrogen atomic clock.

[0006] An embodiment of the present invention provides a hydrogen atomic clock temperature control system, comprising at least one temperature control subsystem, the temperature control subsystem comprising a control module, a temperature detection module and a temperature adjustment module;

[0007] The temperature detection module is arranged outside the microwave resonant cavity of the hydrogen atomic clock, and the temperature detection module is used to collect the temperature of the microwave resonant cavity;

[0008] The temperature regulation module includes a cooling unit and a heating unit; the cooling unit and the heating unit are arranged outside the microwave resonant cavity; the cooling unit is used to cool the microwave resonant cavity; the heating unit is used to heat the microwave resonant cavity;

[0009] The control module is electrically connected to the refrigeration unit, the heating unit and the temperature detection module respectively; the control module is used to adjust the temperature of the microwave resonant cavity through the refrigeration unit or the heating unit.

[0010] Optionally, the temperature control subsystem has a heat preservation mode and a temperature adjustment mode;

[0011] The control module is configured in the keep warm mode as follows:

[0012] When the temperature of the microwave resonant cavity is higher than the upper limit T1 of the first preset temperature range, controlling the refrigeration unit to cool the microwave resonant cavity;

[0013] When the temperature of the microwave resonant cavity is lower than the lower limit T2 of the first preset temperature range, controlling the heating unit to heat the microwave resonant cavity;

[0014] The control module is configured in thermostat mode as follows:

[0015] The target temperature adjustment power is calculated based on the difference between the temperature of the microwave resonant cavity and the target adjustment temperature T3;

[0016] When the temperature of the microwave resonant cavity is higher than the upper limit T4 of the second preset temperature range, controlling the refrigeration unit to adjust the power according to the target temperature to cool the microwave resonant cavity;

[0017] When the temperature of the microwave resonant cavity is lower than the lower limit T5 of the second preset temperature range, the heating unit is controlled to adjust the power to heat the microwave resonant cavity according to the target temperature.

[0018] Optionally, the hydrogen atomic clock temperature control system includes a temperature holding stage and a temperature adjustment stage;

[0019] During the insulation phase, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem in the insulation mode;

[0020] During the temperature adjustment stage, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem in a temperature preservation mode and at least one temperature control subsystem in a temperature adjustment mode.

[0021] Optionally, the microwave resonant cavity includes at least two temperature control areas; the temperature control areas correspond to the temperature control subsystems one by one; and at least one of the preset temperature ranges and target adjustment temperatures of different temperature control subsystems is different.

[0022] Optionally, the hydrogen atomic clock temperature control system includes at least one first temperature control subsystem and at least one second temperature control subsystem;

[0023] The microwave resonant cavity comprises a first heat-insulating cavity, a second heat-insulating cavity and a third heat-insulating cavity, wherein the first heat-insulating cavity, the second heat-insulating cavity and the third heat-insulating cavity are coaxially sleeved in sequence from the inside to the outside;

[0024] The first temperature control subsystem is used to control the temperature between the first insulation cavity and the second insulation cavity;

[0025] The second temperature control subsystem is used to control the temperature between the second insulation cavity and the third insulation cavity;

[0026] The temperature detection module in the first temperature control subsystem is arranged between the first insulation cavity and the second insulation cavity, and is used to detect the temperature between the first insulation cavity and the second insulation cavity;

[0027] The temperature detection module in the second temperature control subsystem is arranged between the second insulation cavity and the third insulation cavity, and is used to detect the temperature between the second insulation cavity and the third insulation cavity.

[0028] Optionally, in the at least one first temperature control subsystem and the at least one second temperature control subsystem, the temperature adjustment module of at least one temperature control subsystem only includes a heating unit.

[0029] Optionally, the microwave resonant cavity includes at least three temperature control areas; the temperature control areas correspond to the temperature control subsystems one by one; and at least one of the preset temperature ranges and target adjustment temperatures of different temperature control subsystems is different;

[0030] At least one first temperature control subsystem is included between the first insulation cavity and the second insulation cavity, corresponding to at least one temperature control area;

[0031] At least two second temperature control subsystems corresponding to at least two temperature control areas are included between the second insulation cavity and the third insulation cavity;

[0032] During the temperature adjustment stage, the hydrogen atomic clock temperature control system includes at least one second temperature control subsystem in a temperature preservation mode and at least one first temperature control subsystem in a temperature adjustment mode.

[0033] Optionally, the hydrogen atomic clock temperature control system further includes a power supply; the temperature detection module includes a thermistor; the control module includes a first resistor, a second resistor, a third resistor and a differential amplifier;

[0034] One end of the first resistor is connected to a power supply, the other end of the first resistor is connected to a thermistor, and the connection node is a first connection node, and the other end of the thermistor is grounded; one end of the second resistor is connected to the power supply, the other end of the second resistor is connected to a third resistor, and the connection node is a second connection node, and the other end of the third resistor is grounded; a first comparison terminal of the differential amplifier is connected to the first connection point, and a second comparison terminal of the differential amplifier is connected to the second connection point;

[0035] Wherein, when the resistance values of the thermistor and the first resistor are not equal, the differential amplifier outputs a deviation voltage; the deviation voltage serves as a temperature signal of the microwave resonant cavity.

[0036] Optionally, the heating unit includes components and a heating structure, and the components include a first switching diode, a first operational amplifier circuit, and a first power amplifier;

[0037] The anode of the first switching diode is connected to the control module, the cathode of the first switching diode is connected to the anode of the first operational amplifier circuit, the cathode of the first operational amplifier is connected to the anode of the first power amplifier, and the cathode of the first power amplifier is connected to the heating unit;

[0038] The refrigeration unit includes components and a refrigeration structure, wherein the components include a second switching diode, a second operational amplifier circuit and a second power amplifier;

[0039] The positive pole of the second switching diode is connected to the control module, the negative pole of the second switching diode is connected to the positive pole of the second operational amplifier circuit, the positive pole of the second operational amplifier is connected to the positive pole of the second power amplifier, and the negative pole of the second power amplifier is connected to the refrigeration unit.

[0040] Optionally, the heating structure is an electric heating wire, which is arranged outside the microwave resonant cavity in a double-wire reverse winding manner.

[0041] Optionally, the refrigeration structure includes a semiconductor refrigerator, a refrigeration pipe and a refrigeration medium. The refrigeration pipe is wound around the outside of the microwave resonant cavity. There is a refrigeration medium in the refrigeration pipe. The semiconductor refrigerator is used to reduce the temperature of the refrigeration medium. The refrigeration medium exchanges heat with the microwave resonant cavity to reduce the temperature of the microwave resonant cavity.

[0042] An embodiment of the present invention provides a hydrogen atomic clock temperature control system, comprising at least one temperature control subsystem, which includes a control module, a temperature detection module, and a temperature adjustment module. The temperature detection module is used to collect the temperature of the microwave resonant cavity. A refrigeration unit is used to cool the microwave resonant cavity, and a heating unit is used to heat the microwave resonant cavity. The two work together to achieve rapid temperature adjustment and stable maintenance. This overcomes the limitation of existing hydrogen atomic clock temperature control systems, which only have a one-way heating function and lack a cooling function, and achieves rapid temperature adjustment and stable maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A schematic structural diagram of a hydrogen atomic clock temperature control system provided by an embodiment of the present invention;

[0044] Figure 2 A schematic structural diagram of a microwave resonant cavity provided in an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of the circuit structure of a temperature control subsystem provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0047] The embodiment of the present invention provides a hydrogen atomic clock temperature control system, Figure 1 A schematic diagram of the structure of a hydrogen atomic clock temperature control system provided by an embodiment of the present invention. Figure 2 A schematic structural diagram of a microwave resonant cavity provided in an embodiment of the present invention.

[0048] like Figure 1-Figure 2As shown, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem, and the temperature control subsystem includes a control module 10, a temperature detection module 20 and a temperature adjustment module 30.

[0049] The temperature detection module 20 is disposed outside the microwave resonant cavity 40 of the hydrogen atomic clock. The temperature detection module 20 is used to collect the temperature of the microwave resonant cavity 40 .

[0050] The temperature adjustment module 30 includes a cooling unit 31 and a heating unit 32 ; the cooling unit 31 and the heating unit 32 are arranged outside the microwave resonant cavity 40 ; the cooling unit 31 is used to cool the microwave resonant cavity 40 ; the heating unit 32 is used to heat the microwave resonant cavity 40 .

[0051] The control module 10 is electrically connected to the refrigeration unit 31 , the heating unit 32 and the temperature detection module 20 , respectively. The control module 10 is used to adjust the temperature of the microwave resonant cavity 40 through the refrigeration unit 31 or the heating unit 32 .

[0052] Specifically, during operation, the temperature detection module 20 collects the temperature of the microwave resonant cavity 40 in real time and transmits the data to the control module 10. The control module 10 is pre-set with a preset temperature range of the microwave resonant cavity 40, which is determined by the operating temperature T0 and the floating accuracy ΔT.

[0053] For example, the preset operating temperature T0 can be set between 263.15K and 338.15K (-10°C to 65°C) depending on the model of the hydrogen atom maser and the ambient temperature of the application scenario. The floating accuracy can be adjusted within the range of ±0.01K to ±5K based on actual needs. If the preset operating temperature T0 = 320.65K (47.5°C) and the floating accuracy ΔT = 2.5K, the preset temperature range is 318.15 to 323.15K.

[0054] During the temperature maintenance phase, the temperature detection module 20 continuously monitors temperature changes, and the control module 10 fine-tunes the operating states of the cooling unit 31 and the heating unit 32 according to real-time temperature data to stabilize the temperature.

[0055] Specifically, when the temperature data fed back by the temperature detection module 20 indicates that the temperature of the microwave resonant cavity 40 deviates from the preset temperature range, the control module 10 controls the temperature adjustment module 30 to restore the temperature to the preset temperature range. If the current temperature is higher than the upper limit of the preset temperature range, the control module 10 sends a command to the cooling unit 31 to activate the cooling function and cool the microwave resonant cavity 40. If the current temperature is lower than the lower limit of the preset temperature range, the control module 10 controls the heating unit 32 to start operating and heat the microwave resonant cavity 40.

[0056] For example, in an application scenario with higher precision requirements, for example, in order to obtain an atomic excitation accuracy of less than 1×10-15 frequency, the control module 10 will further enhance the control accuracy so that the temperature stability in the preset temperature range is less than 7×10-3K and the temperature gradient is ≤0.05K, thereby ensuring high-precision timing of the hydrogen atomic clock.

[0057] The hydrogen atomic clock also includes a startup phase during use, during which the temperature of the resonant cavity of the hydrogen atomic clock is gradually adjusted from the ambient temperature to the operating temperature range.

[0058] During the startup phase, the control module 10 precisely regulates the working intensity of the cooling unit 31 and the heating unit 32 to ensure that the temperature change (temperature gradient) per unit time does not exceed ±0.5K.

[0059] It should be noted that the hydrogen atomic clock provided in the embodiment of the present invention has a composite temperature control scheme of a refrigeration unit 31 and a heating unit 32. Therefore, compared with the hydrogen atomic clock temperature control system that only has a one-way heating function but lacks a refrigeration function, the operating temperature and operating temperature range of the hydrogen atomic clock can be set near the ambient temperature, thereby achieving the purpose of rapid startup.

[0060] An embodiment of the present invention provides a hydrogen atomic clock temperature control system, comprising at least one temperature control subsystem, which includes a control module, a temperature detection module, and a temperature adjustment module. The temperature detection module is used to collect the temperature of the microwave resonant cavity. A refrigeration unit is used to cool the microwave resonant cavity, and a heating unit is used to heat the microwave resonant cavity. The two work together to achieve rapid temperature adjustment and stable maintenance. This overcomes the limitation of existing hydrogen atomic clock temperature control systems, which only have a one-way heating function and lack a cooling function, and achieves rapid temperature adjustment and stable maintenance.

[0061] Optionally, the temperature control subsystem has a heat preservation mode and a temperature adjustment mode, each of which has different preset temperature ranges and temperature stabilities. In the temperature adjustment mode, the temperature control subsystem's primary task is to adjust the current microwave resonant cavity to a second preset temperature range using a preset temperature gradient. When the temperature of the microwave resonant cavity reaches the second preset temperature range for a period of time, the temperature control subsystem switches from the temperature adjustment mode to the heat preservation mode. In the heat preservation mode, the temperature control subsystem's primary task is to provide a stable temperature environment outside the microwave resonant cavity. Therefore, compared to the temperature adjustment mode, the heat preservation mode has a smaller preset temperature range, higher temperature stability, and a smaller floating precision ΔT.

[0062] The control module 10 is configured in the keep warm mode as follows:

[0063] When the temperature of the microwave resonant cavity 40 is higher than the upper limit T1 of the first preset temperature range, the refrigeration unit 31 is controlled to cool the microwave resonant cavity 40;

[0064] When the temperature of the microwave resonant cavity 40 is lower than the lower limit T2 of the first preset temperature range, the heating unit 32 is controlled to heat the microwave resonant cavity 40;

[0065] Among them, the upper limit T1 of the first preset temperature range can be understood as the working temperature T0 + floating accuracy △T; the lower limit T2 of the first preset temperature range can be understood as the working temperature T0 - floating accuracy △T; the insulation mode can be understood as adjusting to maintain the temperature when the temperature deviates from the preset range.

[0066] Specifically, when the temperature control subsystem is in insulation mode, the temperature detection module 20 collects the temperature of the microwave resonant cavity 40 in real time and transmits the data to the control module 10. The control module 10 is pre-set with a first preset temperature range [T1, T2] for the microwave resonant cavity 40. The control module 10 controls the temperature adjustment module 30 to restore the temperature to the preset temperature range. If the current temperature is higher than the upper limit T1 of the first preset temperature range, the control module 10 sends a command to the cooling unit 31 to activate the cooling function and cool the microwave resonant cavity 40. If the current temperature is lower than the lower limit T2 of the first preset temperature range, the control module 10 controls the heating unit 32 to start operating and heat the microwave resonant cavity 40.

[0067] The control module 10 is configured in the temperature adjustment mode as follows:

[0068] The target temperature adjustment power is calculated based on the difference between the temperature of the microwave resonant cavity 40 and the target adjustment temperature T3.

[0069] When the temperature of the microwave resonant cavity 40 is higher than the upper limit T4 of the second preset temperature range, the refrigeration unit 31 is controlled to adjust the power according to the target temperature to cool the microwave resonant cavity 40;

[0070] When the temperature of the microwave resonant cavity 40 is lower than the lower limit T5 of the second preset temperature range, the heating unit 32 is controlled to adjust the power according to the target temperature to heat the microwave resonant cavity 40;

[0071] Among them, the target temperature adjustment power can be understood as being set based on the current hydrogen atomic clock's ability to withstand temperature changes; the temperature adjustment mode can be understood as actively adjusting to the target temperature according to the preset power.

[0072] Specifically, in the temperature control subsystem's temperature adjustment mode, the control module 10 determines the target adjustment temperature T3 based on the hydrogen atomic clock's operating status and environmental parameters, calculates the difference between the current temperature and T3, and calculates the upper limit T4 and lower limit T5 of the second preset temperature range based on the floating precision ΔT. After accounting for cavity temperature fluctuations caused by thermal inertia and heat conduction, the temperature of the microwave resonant cavity 40 is adjusted at the target temperature adjustment power to ensure that the temperature of the microwave resonant cavity 40 ultimately remains within the second preset temperature range [T4, T5].

[0073] For example, during the startup phase of the hydrogen atomic clock, if the room temperature is 25° (i.e., the temperature of the microwave resonant cavity 40 is 25°), the frequency of the microwave resonant cavity is 1.420 GHz, corresponding to the operating temperature of 27.5° (i.e., the target adjustment temperature T3 = 27.5°), the floating accuracy △T = ±0.5°, at this time, the control module 10 enters the temperature adjustment mode.

[0074] First, obtain the current temperature and floating precision ΔT, calculate the second preset temperature range of 27° to 28°, and calculate the difference between the current temperature and the target adjustment temperature T3 (27.5°) to be +2.5° (needing a temperature increase). Based on the system's heat capacity, thermal conductivity characteristics, and the hydrogen atomic clock cavity's ability to withstand temperature changes, calculate the required target temperature adjustment power, such as 50W.

[0075] Then, the power is adjusted to the target temperature to continue heating the microwave resonant cavity 40 so that the microwave resonant cavity 40 enters the second preset temperature range with a temperature variation curve that is as smooth as possible.

[0076] Optionally, the hydrogen atomic clock temperature control system includes a temperature holding stage and a temperature adjustment stage;

[0077] During the insulation phase, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem in the insulation mode;

[0078] During the temperature adjustment stage, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem in a temperature preservation mode and at least one temperature control subsystem in a temperature adjustment mode.

[0079] Specifically, the system may include multiple temperature control subsystems. During the insulation phase of the hydrogen maser temperature control system, at least one temperature control subsystem operates in insulation mode, and some temperature control subsystems may be in temperature adjustment mode, depending on the difference between the current temperature and the target adjustment temperature. The core goal of this phase is to maintain the microwave resonant cavity as a whole or its key areas in an extremely stable and narrowly fluctuating temperature environment (i.e., the first preset temperature range [T1, T2]) to minimize the impact of temperature fluctuations on the atomic transition frequency and ensure the long-term frequency stability of the hydrogen maser. All subsystems in insulation mode work independently or collaboratively to monitor the temperature of their responsible areas, and when the temperature deviates from its preset narrow range, they make fine adjustments to bring the temperature back to the set range.

[0080] During the temperature control phase of the hydrogen maser, such as at startup, the temperature control system employs a more complex hybrid heating mode strategy: at least one temperature control subsystem is placed in temperature control mode. This subsystem is used to actively and uniformly change the temperature of its responsible region, approaching the target adjustment temperature T3 according to a preset temperature gradient (or power calculated based on the temperature difference), and ultimately stabilizing within a relatively wide second preset temperature range [T4, T5]. Simultaneously, at least one temperature control subsystem remains in or switches to insulation mode, providing local thermal environment stability or thermal boundary control for the temperature control region. For example, insulation of the sides or bottom of the microwave resonant cavity can reduce the impact of external thermal interference on the core temperature control process or prevent excessive heat loss or inflow to / from non-target areas, thereby improving temperature control efficiency and protecting the structure.

[0081] Optionally, the microwave resonant cavity 40 includes at least two temperature control areas; the temperature control areas correspond to the temperature control subsystems one by one; and at least one of the preset temperature range and the target adjustment temperature of different temperature control subsystems is different.

[0082] Specifically, the temperature control area can be understood as different physical or functional areas on the microwave resonant cavity 40, such as the top, side, and bottom. In application scenarios with higher precision requirements, these areas can be further subdivided into more sub-areas. Due to the differences in thermal conductivity, exposure to the environment, distance from the core working area, and structural functions of different areas, their sensitivity to temperature changes and required control accuracy may vary. Therefore, different temperature control areas are managed by different temperature control subsystems, and at least one of the preset temperature ranges and target adjustment temperatures of different temperature control subsystems is different.

[0083] By dividing different positions on the microwave resonant cavity 40 into multiple temperature control zones, local temperature control and heating compensation adjustment are formed for each zone, and a non-uniform heating arrangement is adopted to achieve high-precision temperature control of different zones, making the temperature distribution of the entire microwave resonant cavity 40 more uniform and the overall temperature difference smaller.

[0084] Continue to refer Figure 2 In an optional embodiment, the hydrogen atomic clock temperature control system includes at least one first temperature control subsystem and at least one second temperature control subsystem;

[0085] The microwave resonant cavity 40 includes a first heat-insulating cavity 41, a second heat-insulating cavity 42 and a third heat-insulating cavity 43, which are coaxially sleeved from the inside to the outside.

[0086] The first temperature control subsystem is used to control the temperature between the first insulation cavity 41 and the second insulation cavity 42;

[0087] The second temperature control subsystem is used to control the temperature between the second insulation cavity 42 and the third insulation cavity 43;

[0088] The temperature detection module 20 in the first temperature control subsystem is arranged between the first insulation cavity 41 and the second insulation cavity 42, and is used to detect the temperature between the first insulation cavity 41 and the second insulation cavity 42. The temperature detection module 20 in the second temperature control subsystem is arranged between the second insulation cavity 42 and the third insulation cavity 43, and is used to detect the temperature between the second insulation cavity 42 and the third insulation cavity 43.

[0089] Specifically, microwave resonant cavity 40 comprises a first insulation cavity 41, a second insulation cavity 42, and a third insulation cavity 43, arranged coaxially from the inside out. Third insulation cavity 43, the outermost insulation layer, primarily isolates the device from temperature fluctuations in the external environment. Second insulation cavity 42, the middle buffer layer, facilitates heat transfer and stabilizes the internal environment. First insulation cavity 41 houses an atomic storage bubble 44, the core region where hydrogen atom transitions occur and where temperature stability is paramount.

[0090] Exemplarily, the second temperature control subsystem is located relatively externally, creating a relatively stable temperature barrier at the outermost edge of the resonant cavity, effectively isolating the interior from the effects of ambient temperature fluctuations. In this mode, it maintains the temperature of the interlayer region between the second insulation cavity 42 and the third insulation cavity 43 within a preset range.

[0091] The first temperature control subsystem is located in the inner layer closer to the core, and is used for higher-precision temperature control, strictly maintaining the temperature within a narrower preset temperature range, providing an extremely stable working temperature environment for the atomic storage bubble 44, and making the overall temperature control system faster, more accurate, and more stable in temperature maintenance.

[0092] Optionally, in the at least one first temperature control subsystem and the at least one second temperature control subsystem, the temperature adjustment module of at least one temperature control subsystem only includes the heating unit 32 .

[0093] Specifically, the hydrogen atomic clock temperature control system includes at least one first temperature control subsystem (inner layer) and at least one second temperature control subsystem (outer layer). At least one of the inner and outer temperature control subsystems has both heating and cooling capabilities to meet the most basic temperature control needs.

[0094] For example, the inner temperature control subsystem (such as the first temperature control subsystem) usually needs to maintain a high temperature state and is only equipped with a heating unit 31, while the outer temperature control subsystem (such as the second temperature control subsystem) needs to cope with changes in ambient temperature and is equipped with both a heating unit 31 and a cooling unit 32. Conversely, the core components of the hydrogen atomic clock are located in the innermost layer and require the most precise temperature control. The inner temperature control subsystem (such as the first temperature control subsystem) is equipped with a heating unit 31 and a cooling unit 32. In most application scenarios, it is more common for the ambient temperature to be lower than the system target temperature. The outer temperature control subsystem (such as the second temperature control subsystem) is only equipped with a heating unit 31 to simplify the system structure.

[0095] Optionally, the microwave resonant cavity 40 includes at least two temperature control areas; the temperature control areas correspond to the temperature control subsystems one by one; and at least one of the preset temperature range and the target adjustment temperature of different temperature control subsystems is different;

[0096] At least one first temperature control subsystem is included between the first insulation cavity 41 and the second insulation cavity 42, corresponding to at least one temperature control area;

[0097] At least two second temperature control subsystems corresponding to at least two temperature control areas are included between the second insulation cavity 42 and the third insulation cavity 43;

[0098] During the temperature adjustment stage, the hydrogen atomic clock temperature control system includes at least one second temperature control subsystem in a temperature preservation mode and at least one first temperature control subsystem in a temperature adjustment mode.

[0099] Specifically, the microwave resonant cavity 40 is divided into at least three temperature control areas, wherein the inner layer includes at least one first temperature control subsystem corresponding to at least one temperature control area, and the outer layer includes at least two second temperature control subsystems corresponding to at least two temperature control areas.

[0100] During the temperature adjustment stage, the hydrogen atomic clock temperature control system adopts a more complex hybrid heating mode strategy: at least one first temperature control subsystem (located in the inner layer of the microwave resonant cavity 40) will be placed in the temperature adjustment mode. This subsystem is used to actively and uniformly change the temperature of the core area of the microwave resonant cavity 40, approach the target adjustment temperature according to the preset temperature gradient (or the power calculated according to the temperature difference), and finally stabilize within the preset temperature range. At the same time, at least one second temperature control subsystem (located in the outer layer of the microwave resonant cavity 40) will remain in or switch to the insulation mode to provide local thermal environment stability or thermal boundary control for the temperature adjustment area. For example: insulation of the side or bottom area of the microwave resonant cavity can reduce the impact of external thermal interference on the core temperature adjustment process, or prevent excessive heat loss / inflow to / from non-target areas, thereby improving the temperature adjustment efficiency and protecting the structure.

[0101] For example, in one specific embodiment, the hydrogen atomic clock temperature control system utilizes dual-layer precision temperature control, with five independent temperature control subsystems controlling the inner and outer furnace control zones. Specifically, the five independent temperature control circuits for the outer furnace top and bottom, and the inner furnace top, middle, and bottom of the microwave resonant cavity 40 are continuously adjustable from 45°C to 55°C in the middle and bottom portions of the microwave resonant cavity 40, with a stability of 0.001°C. The outer furnace top, middle, and bottom provide a stable temperature environment for the microwave resonant cavity 40, with a stability of 0.01°C.

[0102] Optionally, the hydrogen atomic clock temperature control system further includes a power supply; the temperature detection module 20 includes a thermistor Rn; and the control module 10 includes a first resistor R1, a second resistor R2, a third resistor R3 and a differential amplifier A1.

[0103] One end of the first resistor R1 is connected to the power supply VIN, the other end of the first resistor R1 is connected to the thermistor Rn, and the connection node is a first connection node. The other end of the thermistor Rn is grounded; one end of the second resistor R2 is connected to the power supply VIN, the other end of the second resistor R2 is connected to the third resistor R3, and the connection node is a second connection node. The other end of the third resistor R3 is grounded GND; the first comparison terminal of the differential amplifier A1 is connected to the first connection point, and the second comparison terminal of the differential amplifier A1 is connected to the second connection point.

[0104] The differential amplifier A1 outputs a deviation voltage when the resistance values of the thermistor Rn and the first resistor R1 are not equal; the deviation voltage serves as a temperature signal of the microwave resonant cavity 40 .

[0105] Specifically, the first resistor R1, the second resistor R2, the third resistor R3 and the thermistor Rn form a Wheatstone bridge. The Wheatstone bridge is used in the circuit to detect the resistance change of the thermistor, thereby indirectly measuring the temperature.

[0106] For example, a first resistor R1, a second resistor R2, a third resistor R3, and a thermistor Rn form a Wheatstone bridge. R2 and R3 have the same resistance value. Thermistor Rn is attached to the surface of the microwave resonant cavity, and its resistance changes with temperature. Together with R1, it forms one arm of the bridge, while R2 and R3 form the other arm. A differential amplifier A1 connects the midpoints of the two arms to collect the voltage difference signal.

[0107] When thermistor Rn and first resistor R1 are equal in magnitude, the bridge is balanced. When the microwave cavity temperature changes, the resistance of thermistor Rn changes, causing the bridge to become unbalanced. Differential amplifier A1 then outputs a voltage signal corresponding to the temperature deviation. This signal, after processing, drives temperature adjustment module 30 to adjust the cavity temperature. For example, when the temperature falls below the target value, thermistor Rn is greater than R1, and the bridge outputs a positive deviation voltage, triggering heating unit 32. Conversely, cooling unit 31 is activated or the heating power of heating unit 32 is reduced, achieving stable control of the microwave cavity temperature.

[0108] Optionally, the heating unit 32 includes components and a heating structure, and the components include a first switching diode D1, a first operational amplifier circuit A2, and a first power amplifier A3;

[0109] The anode of the first switching diode D1 is connected to the control module 10, the cathode of the first switching diode D1 is connected to the anode of the first operational amplifier circuit A2, the cathode of the first operational amplifier A2 is connected to the anode of the first power amplifier A3, and the cathode of the first power amplifier A3 is connected to the heating unit 32;

[0110] The refrigeration unit 31 includes components and a refrigeration structure. The components include a second switching diode D2, a second operational amplifier circuit A4, and a second power amplifier A5.

[0111] The anode of the second switching diode D2 is connected to the control module 10, the cathode of the second switching diode D2 is connected to the anode of the second operational amplifier circuit A4, the anode of the second operational amplifier A4 is connected to the anode of the second power amplifier A5, and the cathode of the second power amplifier A5 is connected to the refrigeration unit 31.

[0112] Specifically, when the bridge outputs a positive bias voltage, indicating the temperature is below the target temperature, the signal output by the control module 10 is forward-conducted by the first switching diode D1 and amplified by the first operational amplifier circuit A2. The signal then drives the heating structure of the heating unit 32 through the first power amplifier A3 to initiate heating, thereby increasing the temperature of the microwave resonant cavity.

[0113] When the bridge outputs a negative deviation voltage, it indicates that the temperature is higher than the desired temperature. At this point, the signal output by the control module 10 is forward-conducted by the second switching diode D2 and amplified by the second operational amplifier circuit A4. The signal is then amplified by the second power amplifier A5, which then drives the cooling structure of the cooling unit 31 to initiate cooling, thereby lowering the temperature of the microwave resonant cavity. Alternatively, the control logic reduces the heating power of the heating unit 32 to achieve temperature control.

[0114] It's important to note that the operational amplifier (OPA) amplifies the weak deviation voltage signal output by the bridge to an appropriate amplitude (e.g., from millivolts to volts), addressing the issue of insufficient differential voltage signal strength. Based on the OPA's output signal, the power amplifier further converts the voltage signal into the drive signal required to drive the heating or cooling mechanism, ensuring that the heating or cooling unit can actually perform temperature regulation.

[0115] Optionally, the heating structure is a heating wire 33 , which is arranged outside the microwave resonant cavity 40 in a double-wire reverse winding manner.

[0116] Specifically, two heating wires are wound side by side in opposite directions outside the resonant cavity. When energized, the magnetic fields they generate are in opposite directions, canceling each other out. This prevents the alternating magnetic field generated by the current from interfering with the atomic transitions within the resonant cavity and achieves uniform heating. Furthermore, magnetic field interference can be further reduced by adding a magnetic shielding layer, such as a Permalloy cover.

[0117] When the microwave resonant cavity 40 comprises a multi-layered insulation cavity structure, such as a first insulation cavity 41, a second insulation cavity 42, and a third insulation cavity 43, a set of heating wires is positioned between the first insulation cavity 41 and the second insulation cavity 42. This set of heating wires precisely controls the temperature of the inner core region (e.g., the third insulation cavity 43 where the atomic transition cavity is located). Another set of heating wires is positioned between the second insulation cavity 42 and the third insulation cavity 43. This set of heating wires is primarily used to control the external ambient temperature, for example, to maintain the base temperature of the outer furnace, forming a primary thermal barrier to reduce the impact of external temperature fluctuations on the internal region.

[0118] Optionally, the refrigeration structure includes a semiconductor refrigerator 34, a refrigeration pipe 35 and a refrigeration medium. The refrigeration pipe 35 is wound around the outside of the microwave resonant cavity 40. There is a refrigeration medium in the refrigeration pipe 35. The semiconductor refrigerator 34 is used to reduce the temperature of the refrigeration medium. The refrigeration medium exchanges heat with the microwave resonant cavity 40 to reduce the temperature of the microwave resonant cavity 40.

[0119] Specifically, the cooling structure utilizes semiconductor refrigeration. A cooling pipe 35 is spirally wound around the outer surface of the microwave resonant cavity 40. A refrigerant medium circulates within the pipe, acting as a heat transfer medium. As the low-temperature medium flows through the pipe wrapped around the outer surface of the resonant cavity, it efficiently exchanges heat with the microwave resonant cavity 40, absorbing heat from the cavity and cooling the microwave resonant cavity 40.

[0120] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations, and substitutions are possible for those skilled in the art without departing from the scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A hydrogen atomic clock temperature control system, characterized in that: It includes at least one temperature control subsystem, which includes a control module, a temperature detection module and a temperature adjustment module; The temperature detection module is arranged outside the microwave resonant cavity of the hydrogen atomic clock, and the temperature detection module is used to collect the temperature of the microwave resonant cavity; The temperature adjustment module includes a refrigeration unit and a heating unit; the refrigeration unit and the heating unit are arranged outside the microwave resonant cavity; the refrigeration unit is used to cool the microwave resonant cavity; the heating unit is used to heat the microwave resonant cavity; The control module is electrically connected to the refrigeration unit, the heating unit and the temperature detection module respectively; the control module is used to adjust the temperature of the microwave resonant cavity through the refrigeration unit or the heating unit.

2. The hydrogen atomic clock temperature control system according to claim 1, characterized in that: The temperature control subsystem has a heat preservation mode and a temperature adjustment mode; The control module is configured in the keep warm mode to: When the temperature of the microwave resonant cavity is higher than an upper limit T1 of a first preset temperature range, controlling the refrigeration unit to cool the microwave resonant cavity; When the temperature of the microwave resonant cavity is lower than a lower limit T2 of a first preset temperature range, controlling the heating unit to heat the microwave resonant cavity; The control module is configured in the temperature adjustment mode to: Calculating the target temperature adjustment power according to the difference between the temperature of the microwave resonant cavity and the target adjustment temperature T3; When the temperature of the microwave resonant cavity is higher than an upper limit T4 of a second preset temperature range, controlling the refrigeration unit to adjust power according to the target temperature to cool the microwave resonant cavity; When the temperature of the microwave resonant cavity is lower than a lower limit T5 of a second preset temperature range, the heating unit is controlled to adjust the power to heat the microwave resonant cavity according to the target temperature.

3. The hydrogen atomic clock temperature control system according to claim 2, characterized in that: The hydrogen atomic clock temperature control system includes a heat preservation stage and a temperature adjustment stage; During the insulation stage, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem in the insulation mode; During the temperature adjustment stage, the hydrogen atomic clock temperature control system includes at least one temperature control subsystem in the temperature preservation mode and at least one temperature control subsystem in the temperature adjustment mode.

4. The hydrogen atomic clock temperature control system according to claim 2, characterized in that: The microwave resonant cavity includes at least two temperature control areas; the temperature control areas correspond to the temperature control subsystems one by one; and at least one of the preset temperature range and the target adjustment temperature is different between different temperature control subsystems.

5. The hydrogen atomic clock temperature control system according to claim 1, characterized in that: The hydrogen atomic clock temperature control system includes at least one first temperature control subsystem and at least one second temperature control subsystem; The microwave resonant cavity comprises a first thermal insulation cavity, a second thermal insulation cavity and a third thermal insulation cavity, wherein the first thermal insulation cavity, the second thermal insulation cavity and the third thermal insulation cavity are coaxially sleeved in sequence from the inside to the outside; The first temperature control subsystem is used to regulate the temperature between the first insulation cavity and the second insulation cavity; The second temperature control subsystem is used to control the temperature between the second insulation cavity and the third insulation cavity; The temperature detection module in the first temperature control subsystem is arranged between the first thermal insulation cavity and the second thermal insulation cavity, and is used to detect the temperature between the first thermal insulation cavity and the second thermal insulation cavity; The temperature detection module in the second temperature control subsystem is disposed between the second insulation cavity and the third insulation cavity, and is used to detect the temperature between the second insulation cavity and the third insulation cavity.

6. The hydrogen atomic clock temperature control system according to claim 5, characterized in that: The microwave resonant cavity includes at least three temperature control areas; the temperature control areas correspond to the temperature control subsystems one by one; at least one of the preset temperature range and the target adjustment temperature is different between different temperature control subsystems; At least one of the first temperature control subsystems is included between the first insulation cavity and the second insulation cavity, corresponding to at least one of the temperature control areas; At least two second temperature control subsystems corresponding to at least two temperature control areas are included between the second insulation cavity and the third insulation cavity; During the temperature adjustment stage, the hydrogen atomic clock temperature control system includes at least one second temperature control subsystem in a temperature keeping mode and at least one first temperature control subsystem in a temperature adjustment mode.

7. The hydrogen atomic clock temperature control system according to claim 5, characterized in that: Among the at least one first temperature control subsystem and the at least one second temperature control subsystem, the temperature adjustment module of at least one temperature control subsystem only includes the heating unit.

8. The hydrogen atomic clock temperature control system according to claim 1, characterized in that: The hydrogen atomic clock temperature control system further includes a power supply; the temperature detection module includes a thermistor; the control module includes a first resistor, a second resistor, a third resistor and a differential amplifier; One end of the first resistor is connected to the power supply, the other end of the first resistor is connected to the thermistor, and the connection node is a first connection node, and the other end of the thermistor is grounded; one end of the second resistor is connected to the power supply, the other end of the second resistor is connected to the third resistor, and the connection node is a second connection node, and the other end of the third resistor is grounded; the first comparison terminal of the differential amplifier is connected to the first connection point, and the second comparison terminal of the differential amplifier is connected to the second connection point; Wherein, when the resistance values of the thermistor and the first resistor are not equal, the differential amplifier outputs a deviation voltage; and the deviation voltage serves as the temperature signal of the microwave resonant cavity.

9. The hydrogen atomic clock temperature control system according to claim 1, characterized in that: The heating unit includes components and a heating structure, wherein the components include a first switching diode, a first operational amplifier circuit and a first power amplifier; The anode of the first switching diode is connected to the control module, the cathode of the first switching diode is connected to the anode of the first operational amplifier circuit, the cathode of the first operational amplifier is connected to the anode of the first power amplifier, and the cathode of the first power amplifier is connected to the heating unit; The refrigeration unit includes components and a refrigeration structure, wherein the components include a second switching diode, a second operational amplifier circuit and a second power amplifier; The anode of the second switching diode is connected to the control module, the cathode of the second switching diode is connected to the anode of the second operational amplifier circuit, the anode of the second operational amplifier is connected to the anode of the second power amplifier, and the cathode of the second power amplifier is connected to the refrigeration unit.

10. The hydrogen atomic clock temperature control system according to claim 9, characterized in that: The heating structure is an electric heating wire, which is arranged outside the microwave resonant cavity in a double-wire reverse winding manner.

11. The hydrogen atomic clock temperature control system according to claim 9, characterized in that: The refrigeration structure includes a semiconductor refrigerator, a refrigeration pipe and a refrigeration medium. The refrigeration pipe is wound around the outside of the microwave resonant cavity. The refrigeration pipe contains the refrigeration medium. The semiconductor refrigerator is used to reduce the temperature of the refrigeration medium. The refrigeration medium exchanges heat with the microwave resonant cavity to reduce the temperature of the microwave resonant cavity.

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