Temperature control method and temperature control system for valve

Abstract

A temperature control method and temperature control system for a valve. The temperature control method for a valve comprises: determining a temperature deviation on the basis of the current temperature and a target temperature of a valve (S1); determining a target voltage on the basis of the temperature deviation (S2); determining whether the current voltage of a heating apparatus is consistent with the target voltage, and if the current voltage of the heating apparatus is inconsistent with the target voltage, controlling, on the basis of the target voltage, a voltage adjustment module to adjust a voltage of the heating apparatus, so as to obtain an adjusted voltage (S3); and updating the adjusted voltage to a new current voltage of the heating apparatus, and returning to a determination operation (S4).

Description

Valve temperature control method and temperature control system Technical Field

[0001] The present application relates to the field of semiconductor manufacturing, and in particular, to a temperature control method and a temperature control system for a valve. Background Art

[0002] In the semiconductor equipment manufacturing industry, temperature is a critical parameter influencing processing results. Many components in semiconductor equipment require temperature control, making thermostats a widely used component in these devices. The most common temperature control solution for valves is to heat the valve body with a heater rod and measure temperature with a thermocouple, achieving closed-loop temperature control.

[0003] With the development of existing technologies and the accelerated iteration speed of chip manufacturing processes in the semiconductor industry, the process requirements for temperature control accuracy in reaction chambers and related valve products are constantly increasing.

[0004] Therefore, how to improve temperature control accuracy is a technical problem that technicians in this field urgently need to solve. Summary of the Invention

[0005] The present application aims to solve at least one of the technical problems existing in the prior art, and proposes a valve temperature control method and a temperature control system, which improves the temperature control accuracy by controlling the temperature through a dual closed loop of temperature and voltage.

[0006] To achieve the purpose of this application, a valve temperature control method is provided, comprising:

[0007] Determine the temperature deviation based on the current temperature of the valve and the target temperature;

[0008] determining a target voltage according to the temperature deviation;

[0009] Determine whether the current voltage of the heating device is consistent with the target voltage; if not, control the voltage regulating module to adjust the voltage of the heating device according to the target voltage to obtain an adjusted voltage;

[0010] The adjusted voltage is updated as the new current voltage of the heating device, and the process returns to the determination operation.

[0011] In some embodiments, determining the target voltage according to the temperature deviation includes:

[0012] Determining a target voltage using a first proportional-integral-differential model according to the temperature deviation; and / or

[0013] The step of controlling the voltage regulating module to regulate the voltage of the heating device according to the target voltage to obtain an adjusted voltage includes:

[0014] Determining a voltage regulation parameter using a second proportional-integral-differential model according to the target voltage;

[0015] The voltage regulating module is controlled to regulate the voltage of the heating device according to the voltage regulating parameter to obtain an adjusted voltage.

[0016] In some embodiments, determining the target voltage according to the temperature deviation further includes:

[0017] Determining an adjustment parameter corresponding to a deviation range to which the temperature deviation belongs, the adjustment parameter comprising at least one of a proportional coefficient, an integral coefficient, and a differential coefficient;

[0018] updating the first proportional integral differential model according to the adjustment parameter;

[0019] A target voltage corresponding to the deviation range is determined according to the temperature deviation and the updated first proportional-integral-differential model.

[0020] In some embodiments, there are two deviation ranges, namely a first deviation range and a second deviation range, and each temperature deviation belonging to the second deviation range is greater than each temperature deviation belonging to the first deviation range;

[0021] The determining of the adjustment parameter corresponding to the deviation range to which the temperature deviation belongs includes:

[0022] When the temperature deviation falls within the second deviation range, determining that the adjustment parameters include the proportional coefficient and the differential coefficient;

[0023] When the temperature deviation falls within the first deviation range, determining the adjustment parameter includes the integral coefficient.

[0024] In some embodiments, the voltage regulation module includes a thyristor, and the voltage regulation parameter is a duty cycle of a control signal of the thyristor.

[0025] In some embodiments, the valve is provided with a heating rod and a temperature sensor, the temperature sensor including a first temperature sensor, a second temperature sensor, and a third temperature sensor, the first temperature sensor, the second temperature sensor, and the third temperature sensor being arranged on the outer surface of the valve around the valve port of the valve, the second temperature sensor and the third temperature sensor corresponding to the two ends of the heating rod respectively, and the first temperature sensor being located on the side of the valve port away from the heating rod;

[0026] Before determining the temperature deviation according to the current temperature of the valve and the target temperature, the temperature control method further includes:

[0027] Obtaining measured temperatures of the first temperature sensor, the second temperature sensor, and the third temperature sensor;

[0028] Taking the average of the temperature measured by the second temperature sensor and the temperature measured by the third temperature sensor as a first average temperature;

[0029] An average value of the temperature measured by the first temperature sensor and the first average temperature is taken as the current temperature.

[0030] The present application also provides a temperature control system, including a temperature sensor, a heating device and a control device, wherein the temperature sensor is used to measure the current temperature of the valve, the temperature sensor and the heating device are electrically connected to the control device, and the control device uses any one of the above-mentioned temperature control methods to control the heating device to adjust the temperature of the valve.

[0031] In some embodiments, the heating device is a heating rod, and the temperature sensor includes a first temperature sensor, a second temperature sensor, and a third temperature sensor. The temperature sensors are arranged on the outer surface of the valve around the valve port of the valve, the second temperature sensor and the third temperature sensor correspond to the two ends of the heating rod respectively, and the first temperature sensor is located on the side of the valve port away from the heating rod.

[0032] In some embodiments, the temperature sensor includes a thermocouple and four connection ends, wherein the first connection end and the second connection end of the four connection ends are connected to one end of the thermocouple, and the third connection end and the fourth connection end of the four connection ends are connected to the other end of the thermocouple, the first connection end is used to connect to a current source, the second connection end and the third connection end are used to connect to the two ends of a pressure measuring mechanism respectively, and the fourth connection end is grounded.

[0033] In some embodiments, the second connection end is connected to a first filter resistor and a first filter capacitor, the first end of the first filter resistor is connected to the second connection end, the second end of the first filter resistor is connected to the first end of the first filter capacitor, and the second end of the first filter capacitor is grounded, and / or

[0034] The third connection end is connected to a second filter resistor and a second filter capacitor, the first end of the second filter resistor is connected to the third connection end, the second end of the second filter resistor is connected to the first end of the second filter capacitor, and the second end of the second filter capacitor is grounded.

[0035] In some embodiments, a third filter capacitor is further provided between the second connection terminal and the third connection terminal, for filtering out a differential mode signal between the second connection terminal and the third connection terminal.

[0036] This application has the following beneficial effects:

[0037] The temperature control method of the valve provided in the present application includes: determining a temperature deviation based on the current temperature and target temperature of the valve; determining a target voltage based on the temperature deviation; judging whether the current voltage of the heating device is consistent with the target voltage, and if not, controlling the voltage regulating module to adjust the voltage of the heating device according to the target voltage to obtain an adjusted voltage; updating the adjusted voltage to the new current voltage of the heating device, and returning to the judgment operation. The temperature control method of the valve provided in the present application controls the voltage regulating module to adjust the voltage of the heating device according to the temperature deviation between the current temperature and the target temperature, so that the voltage of the heating device can be made close to the target voltage, thereby making the valve temperature close to the target temperature, thereby realizing closed-loop control of the valve temperature. After controlling the voltage regulating module to adjust the voltage of the heating device, the adjusted voltage can be updated to the new current voltage of the heating device, and re-judgment can be made whether it is consistent with the target voltage, thereby realizing closed-loop control of the voltage of the heating device. The temperature control method adopted in the present application adds voltage closed-loop control on the basis of temperature closed-loop control. The dual closed-loop control method makes the control of the heating device more precise, thereby improving the accuracy of temperature control.

[0038] The present application also provides a temperature control system that uses the above control method to control the heater and has the above advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG1 is a flow chart of a valve temperature control method provided in a specific embodiment of the present application;

[0040] FIG2 is a flow chart of a valve temperature control method provided by another embodiment of the present application;

[0041] Figure 3 is the response curve of the regulation process;

[0042] FIG4 is a schematic diagram of the structure of a temperature sensor in a temperature control system provided in a specific embodiment of the present application;

[0043] FIG5 is a schematic structural diagram of a valve in a specific embodiment of the present application.

[0044] 1 to 5 are denoted as follows: 100 , temperature sensor; 101 , thermocouple; 110 , first temperature sensor; 120 , second temperature sensor; 130 , third temperature sensor; 200 , valve; and 300 , heating rod. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solution of the present application, the temperature control method and temperature control system of the valve provided by the present application are described in detail below with reference to the accompanying drawings.

[0046] The temperature control method of the valve provided in this application, as shown in FIG1 , includes:

[0047] S1. Determine the temperature deviation based on the current temperature and target temperature of the valve;

[0048] The valve temperature can be measured by a temperature sensor. A valve can have one or more temperature measurement points. When there are two or more temperature measurement points, the current valve temperature can be calculated by taking the geometric mean, arithmetic mean, or other processing of the current temperatures measured at each temperature measurement point. The target temperature can be set by the user or obtained using other methods, as required. The temperature deviation can be the absolute value of the difference between the current temperature and the target temperature.

[0049] S2. Determine the target voltage based on the temperature deviation;

[0050] In one specific embodiment of the present application, a first proportional-integral-differential (PID) model is used to determine the target voltage based on the temperature deviation. Specifically, the temperature deviation can serve as the input of the first PID model, and the target voltage is the output of the first PID model. Of course, the user can also use other methods to determine the target voltage, such as using an MPC (Model Predictive Control) algorithm, which is not limited here.

[0051] S3, determining whether the current voltage of the heating device is consistent with the target voltage; if not, controlling the voltage regulating module to adjust the voltage of the heating device according to the target voltage to obtain an adjusted voltage;

[0052] The current voltage of the heater can be acquired through components such as an analog-to-digital converter. The voltage regulator module can be used to adjust the heater voltage to bring it closer to the target voltage. This changes the heater power and brings the valve temperature closer to the target temperature. However, due to control accuracy limitations, the heater voltage often deviates from the target voltage.

[0053] S4. Update the adjusted voltage to the new current voltage of the heating device, and return to step S3.

[0054] After the voltage regulation module adjusts the voltage of the heating device, it can re-collect the voltage of the heating device. The collected voltage is the adjusted voltage, and the adjusted voltage is updated as the new current voltage of the heating device. Returning to step S3, the new current voltage is compared with the target voltage, thus achieving closed-loop voltage control.

[0055] The temperature control method of the valve provided in the embodiment of the present application controls the voltage of the heating device to be close to the target voltage by controlling the voltage regulating module to adjust the voltage of the heating device according to the temperature deviation between the current temperature and the target temperature, thereby making the voltage of the heating device close to the target temperature, thereby achieving closed-loop control of the valve temperature. After the voltage regulating module is controlled to adjust the voltage of the heating device, the adjusted voltage can be updated to the new current voltage of the heating device, and it can be re-judged whether it is consistent with the target voltage, thereby achieving closed-loop control of the voltage of the heating device. The temperature control method adopted in the present application adds voltage closed-loop control on the basis of temperature closed-loop control. This dual closed-loop control method can improve the response time and smoothness of the temperature curve, and respond quickly and accurately when the temperature changes, while avoiding the occurrence of integral supersaturation and overshoot, thereby making the control of the heating device more accurate, thereby improving the accuracy of temperature control.

[0056] In some embodiments, the above step S2, i.e., determining the target voltage according to the temperature deviation, further includes:

[0057] The target voltage is determined according to the temperature deviation using a first proportional integral differential model.

[0058] The proportional term of the first proportional-integral-derivative model includes the temperature deviation, the integral term includes the historical deviation, and the differential term includes the time change rate of the temperature deviation.

[0059] In some embodiments, the first PID model is as follows:

[0060] Where, u(t) is the target voltage, K p is the proportionality coefficient, K I is the integral coefficient, K D is the differential coefficient, and err(t) is the temperature deviation.

[0061] As shown in FIG2 , in some embodiments, step S1 includes the following steps:

[0062] S11, receiving the set target temperature SP;

[0063] S12. After receiving the set target temperature SP, calculate the current temperature deviation err n = target temperature SP - current temperature PV n , where n is the temperature of the nth temperature measurement point, n=1,2,...,N, and N is the number of temperature measurement points. The proportional term of the first proportional integral differential model used in the temperature control method of this application is K p ×err n , historical bias The integral term is The time rate of change of temperature deviation is The differential term is K D ×V err .

[0064] In some embodiments, in the above step S3, controlling the voltage regulating module to regulate the voltage of the heating device according to the target voltage to obtain the adjusted voltage includes:

[0065] S31, determining voltage regulation parameters using a second proportional-integral-differential model according to the target voltage;

[0066] The second PI / D model uses the target voltage as input and the voltage regulation parameter as output. Thus, the corresponding voltage regulation parameter can be obtained based on the target voltage through the second PI / D model. Of course, the integral term, proportional term, and differential term of the second PI / D model can be set according to user needs and are not limited here.

[0067] S32. Control the voltage regulating module to regulate the voltage of the heating device according to the voltage regulating parameter to obtain an adjusted voltage.

[0068] Specifically, in the above step S32, the voltage regulation parameter is input into the voltage regulation module, so that the voltage regulation module can regulate the voltage of the heating device according to the voltage regulation parameter to achieve the target voltage.

[0069] In some embodiments, the above step S4 includes the following steps:

[0070] S41 , updating the adjusted voltage to the new current voltage of the heating device, and returning to step S31 .

[0071] S42. Provide a new current voltage of the heating device.

[0072] S43. Obtain a new current temperature.

[0073] In some embodiments, the voltage regulation module includes a thyristor. A thyristor is a power control device based on a thyristor (power electronic device), also known as a thyristor voltage regulator. It has the advantages of high efficiency, no mechanical noise and wear, fast response, small size, and light weight.

[0074] On this basis, in some embodiments, the voltage regulation parameter is, for example, the duty cycle of the control signal of the thyristor. In step S31, the duty cycle of the control signal is determined based on the target voltage using a second proportional-integral-differential model. In step S32, the control signal is output to the thyristor to adjust the voltage output by the thyristor to the heating device to the target voltage.

[0075] Changing the duty cycle of the control signal input to the thyristor can change the output voltage of the thyristor to the heating device. Of course, users can also use other voltage regulating modules and adopt corresponding control methods according to the voltage regulating modules, which is not limited here.

[0076] In some embodiments, when there is EMC (Electromagnetic Compatibility) electromagnetic interference or voltage disturbance, temperature control can be performed through the voltage loop. At this time, the controller has the smallest amount of calculation and the fastest dynamic response, which avoids the phenomenon of single-loop integral oversaturation. Based on the fact that the temperature deviation err is consistent with the voltage change trend, the dual closed-loop control method adopted in this application is divided into an outer temperature loop and an inner voltage loop. The output of the outer temperature loop serves as the input of the inner voltage loop. In the outer temperature loop control, the inner voltage loop must be used. Whether there is EMC electromagnetic interference or voltage disturbance can be judged by monitoring the voltage waveform. When a disturbance occurs, the frequency or amplitude of the voltage will change. If the current temperature is equal to the target temperature, when the voltage fluctuates, the voltage can be adjusted only through the voltage loop.

[0077] In this embodiment, the proportional term controls the system's response time, the differential term eliminates the system's steady-state error, and the differential term adjusts overshoot and dynamic deviation. Together, the integral, proportional, and differential terms alter the smoothness and response time of the system's response curve. By adjusting these parameters, temperature control requirements can be achieved.

[0078] In some embodiments, the above step S2, i.e., determining the target voltage according to the temperature deviation, further includes:

[0079] S21, determining an adjustment parameter corresponding to a deviation range to which the temperature deviation belongs, where the adjustment parameter includes at least one of a proportional coefficient, an integral coefficient, and a differential coefficient;

[0080] S22, updating the first proportional integral differential model according to the adjustment parameters;

[0081] S23 : Determine a target voltage corresponding to the deviation range according to the temperature deviation and the updated first proportional-integral-differential model.

[0082] The temperature control method provided in the embodiment of the present application can set several deviation ranges, that is, the temperature deviation is divided into multiple intervals, and each deviation range corresponds to a different adjustment parameter. After determining the deviation range to which the temperature deviation belongs, the corresponding adjustment parameter can be determined. Then, the first proportional integral differential model is updated according to the adjustment parameter, and at least one of the proportional coefficient, integral coefficient and differential coefficient of the first proportional integral differential model is changed. The temperature deviation err is input into the updated first proportional integral differential model to obtain a target voltage corresponding to the deviation range, and then the target voltage can be determined according to the deviation range to which the temperature deviation belongs, using the first proportional integral differential model corresponding thereto, that is, to achieve segmented control of the temperature to meet the requirements of overshoot and adjustment time.

[0083] In some embodiments, there are two deviation ranges, namely a first deviation range and a second deviation range, and each temperature deviation within the second deviation range is greater than each temperature deviation within the first deviation range. In this case, step S21, i.e., determining the adjustment parameter corresponding to the deviation range to which the temperature deviation belongs, includes:

[0084] S211. When the temperature deviation falls within the second deviation range, determining that the adjustment parameters include a proportional coefficient and a differential coefficient;

[0085] S212: When the temperature deviation falls within the first deviation range, determine that the adjustment parameters include an integral coefficient.

[0086] In a specific embodiment of the present application, as shown in FIG2 , there are two deviation ranges |err|, namely a first deviation range and a second deviation range. The first deviation range is less than or equal to 10°C, and the second temperature deviation range is greater than 10°C. When the temperature deviation err is greater than 10°C, that is, it falls within the second temperature deviation range, the temperature control method changes the proportional coefficient K of the first proportional integral differential model. P and differential coefficient K D , to quickly adjust the temperature so that the temperature returns to within the deviation threshold. That is, the adjustment parameters corresponding to the second deviation range where the temperature deviation err is greater than 10°C include the proportional coefficient K P and differential coefficient K D When the temperature deviation err is less than or equal to 10°C, that is, it belongs to the first temperature deviation range, by changing the integral coefficient K of the first proportional integral differential model I , in order to accurately adjust the temperature, the smoothness of the temperature curve and the accuracy of the adjustment can be improved. That is, the adjustment parameters corresponding to the first deviation range of the temperature deviation err less than or equal to 10°C include the integral coefficient K I Of course, users can set the number and size of the deviation range according to their needs, and there is no limit here.

[0087] Furthermore, temperature deviations within different deviation ranges use different adjustment parameters for the first proportional-integral-differential model, meaning that temperature deviations within different deviation ranges are adjusted differently. As shown in Figure 2, when the temperature deviation is large (e.g., greater than 10°C), the adjustment method for that deviation range is rapid adjustment using the proportional and differential terms. However, when the temperature deviation is small (e.g., less than or equal to 10°C), the adjustment method for that deviation range is precise adjustment using the integral term. This not only improves response speed but also ensures control accuracy. Here, we take two sets of temperature deviations (err) as an example. The first set (10°C, 15°C, 25°C, 50°C, 75°C, and 100°C) falls within the deviation range of |err| > 10°C, while the second set (1°C, 2°C, 5°C, and 9°C) falls within the deviation range of |err| ≤ 10°C. Calibration and fitting are performed on each set of temperature deviations (err) to obtain corresponding temperature deviation-temperature curves. This ensures that, over the full range of temperature deviations (|err| ≤ 10°C and |err| > 10°C), the adjustment time is controlled within 5 minutes and the overshoot of the temperature response curve is less than 0.5%. Figure 3 is a schematic diagram of the adjustment process. The horizontal axis of Figure 3 represents the adjustment time t, and the vertical axis represents the final value ratio y(t) corresponding to the adjustment time t. This final value ratio y(t) can also be expressed as a percentage. In Figure 3, the delay time is the time it takes to reach 50% of the final value for the first time, the rise time is the time required from 0 to the first reaching of the final value, the peak time is the time required to cross the final value to reach the first peak, the settling time is the shortest time required for the response to remain within the error band of ±5% (or ±3%) of the final value, and the overshoot is the percentage by which the peak value exceeds the final value.

[0088] In some embodiments, as shown in FIG5 , the valve 200 is provided with a heater rod 300 and a temperature sensor 100. The temperature sensor 100 includes a first temperature sensor 110, a second temperature sensor 120, and a third temperature sensor 130. The first temperature sensor 110, the second temperature sensor 120, and the third temperature sensor 130 are disposed on the outer surface of the valve 200, surrounding the valve opening of the valve 200. The second temperature sensor 120 and the third temperature sensor 130 correspond to the two ends of the heater rod 300, respectively. The first temperature sensor 110 is located on the side of the valve opening away from the heater rod 300. Of course, the user can also set the number and location of the heater rods and temperature sensors as needed, and this is not limited here.

[0089] On this basis, before the above step S1, i.e., determining the temperature deviation according to the current temperature of the valve 200 and the target temperature, the temperature control method further includes:

[0090] Obtaining the measured temperatures of the first temperature sensor 110 , the second temperature sensor 120 , and the third temperature sensor 130 ;

[0091] The average value of the temperature measured by the second temperature sensor 120 and the temperature measured by the third temperature sensor 130 is taken as the first average temperature; the average value of the temperature measured by the first temperature sensor 110 and the first average temperature is taken as the current temperature.

[0092] Because the first temperature sensor 110 and the second temperature sensor 120 are relatively close to the heating rod 300, the temperatures they measure are relatively accurate, and the first average temperature is relatively close to the temperature of the heating rod 300. Since the third temperature sensor 130 is farther away from the heating rod 300, a more accurate temperature sensor can be used, improving the accuracy of temperature measurement. The average of the temperature measured by the first temperature sensor 110 and the first average temperature is the current temperature, which can more accurately describe the temperature of the valve 200.

[0093] In some embodiments, the temperature mean (i.e., the average of the temperature measured by the first temperature sensor 110 and the first average temperature) can also be combined with the heat conduction equation to obtain the rate of change of temperature over time. When the current temperature reaches the set temperature, the temperature change trend can be quickly determined based on the rate of change of temperature over time, so as to make an early prediction of the temperature change. The heat conduction equation in a three-dimensional isotropic medium is:

[0094] Among them, u is the temperature function of a point in space, t is time, x, y, and z are the three coordinate axes of space, and k is the thermal diffusivity, which depends on the thermal conductivity of the material.

[0095] In this embodiment, at least three temperature measuring points are provided on the valve, and the current temperature is determined by the average temperature of each temperature measuring point, thereby improving the accuracy of temperature detection.

[0096] The present application also provides a temperature control system, including a temperature sensor 100, a heating device and a control device. The temperature sensor 100 is used to measure the current temperature of the valve. The temperature sensor 100 and the heating device are both electrically connected to the control device. The control device uses the temperature control method in any of the above embodiments to control the heating device to adjust the temperature of the valve.

[0097] In some embodiments, as shown in FIG4 , the temperature sensor 100 includes a thermocouple 101 and four connection terminals. The four connection terminals are formed, for example, by four wires, and the internal resistances of the four wires are RL1, RL2, RL3, and RL4, respectively. The first connection terminal (formed by a wire with an internal resistance of RL1) and the second connection terminal (formed by a wire with an internal resistance of RL2) of the four connection terminals are connected to one end of the thermocouple 101, and the third connection terminal (formed by a wire with an internal resistance of RL3) and the fourth connection terminal (formed by a wire with an internal resistance of RL4) of the four connection terminals are connected to the other end of the thermocouple 101. The first connection terminal is used to connect to a current source IOUT0, which outputs current IOUT. The second and third connection terminals are respectively used to connect to the two ends of a pressure measuring mechanism, and the fourth connection terminal is grounded. Current flows from the first connection terminal to the fourth connection terminal through the thermocouple 101. The second and third connection terminals can measure the voltage across the thermocouple 101, thereby determining the temperature of the measurement point. The temperature sensor 100 adopts a four-wire connection method, which can separate the voltage applied to the thermocouple 101 from the current loop, eliminate the influence of the internal resistance of the wire in the current loop, and improve the measurement accuracy.

[0098] In some embodiments, the second connection end and the third connection end are respectively connected to two signal channels (AINP, AINM) of the pressure measuring mechanism, and the two signal channels (AINP, AINM) are used to collect the voltage signals at both ends of the thermocouple 101. The voltage signals at both ends of the thermocouple 101 are a pair of common mode signals, and the pressure measuring mechanism can convert one of the voltage signals so that a pair of common mode signals form a pair of fully differential signals. The pressure measuring mechanism then measures the voltage on the thermocouple 101 by the fully differential signal, thereby eliminating the internal resistance of the wire in the voltage measurement loop and improving measurement accuracy. As shown in Figure 4, a third filter capacitor C3 is also provided between the second connection end and the third connection end. The third filter capacitor C3 is used to filter out the differential mode signal and further improve measurement accuracy. The capacitance value of the third filter capacitor C3 can be 0.1uF. Of course, the user can also set the capacitance value of the third filter capacitor C3 as needed, which is not limited here.

[0099] In some embodiments, as shown in Figure 4, the second connection end is connected to a first filter resistor R1 and a first filter capacitor C1, the first end of the first filter resistor R1 is connected to the second connection end, the second end of the first filter resistor R1 is connected to the first end of the first filter capacitor C1, and the second end of the first filter capacitor C1 is grounded. The first filter resistor R1 and the first filter capacitor C1 form a low-pass filter, which can effectively avoid interference caused by high-frequency AC signals. Furthermore, in some embodiments, the resistance of the first filter resistor R1 is 1KΩ, and the capacitance of the first filter capacitor C1 is 0.01uF. Of course, the user can also set the capacitance value of the first filter resistor R1 and the first filter capacitor C1 as needed, which is not limited here.

[0100] In some embodiments, the third connection terminal is connected to a second filter resistor R2 and a second filter capacitor C2. As shown in Figure 4, the first end of the second filter resistor R2 is connected to the third connection terminal, the second end of the second filter resistor R2 is connected to the first end of the second filter capacitor C2, and the second end of the second filter capacitor C2 is grounded. The second filter resistor R2 and the second filter capacitor C2 form a low-pass filter, which can effectively avoid interference caused by high-frequency AC signals. Furthermore, in some embodiments, the resistance of the second filter resistor R2 is 1KΩ, and the capacitance of the second filter capacitor C2 is 0.01uF. Of course, the user can also set the capacitance value of the second filter resistor R2 and the second filter capacitor C2 as needed, which is not limited here.

[0101] In some embodiments, the fourth connection terminal of the temperature sensor 100 is further connected to a calibration module, which includes a first calibration resistor R5 and a second calibration resistor R6 connected in series between the fourth connection terminal of the temperature sensor 100 and ground. The calibration module also includes a first calibration channel REFIN(+) and a second calibration channel REFIN(-). The first calibration channel REFIN(+) is connected between the first calibration resistor R5 and the fourth connection terminal of the temperature sensor 100, and the second calibration channel REFIN(-) is connected between the first calibration resistor R5 and the second calibration resistor R6. The first calibration channel REFIN(+) and the second calibration channel REFIN(-) can be used to measure the accuracy of the resistance of the thermocouple 101, thereby determining the accuracy of the temperature sensor 100.

[0102] In some embodiments, a sixth filter capacitor C6 is provided between the first verification channel REFIN(+) and the second verification channel REFIN(-). The sixth filter capacitor C6 can be used to filter out differential mode signals, further improving measurement accuracy. The capacitance value of the sixth filter capacitor C6 can be 0.1uF. Of course, the user can also set the capacitance value of the sixth filter capacitor C6 as needed, which is not limited here.

[0103] In some embodiments, a third filter resistor R3 is provided between the fourth connection terminal of the temperature sensor 100 and the first verification channel REFIN(+). As shown in Figure 4, the first end of the third filter resistor R3 is connected to the third connection terminal, the second end of the third filter resistor R3 is connected to the first end of the fourth filter capacitor C4, and the second end of the fourth filter capacitor C4 is grounded. The third filter resistor R3 and the fourth filter capacitor C4 form a low-pass filter, which can effectively avoid interference caused by high-frequency AC signals. In some embodiments, the resistance of the third filter resistor R3 is 1KΩ, and the capacitance value of the fourth filter capacitor C4 is 0.01uF. Of course, the user can also set the capacitance value of the third filter resistor R3 and the fourth filter capacitor C4 as needed, which is not limited here.

[0104] In some embodiments, a fourth filter resistor R4 is provided between the second end of the first verification resistor R5 and the second verification channel REFIN(-). As shown in Figure 4, the first end of the fourth filter resistor R4 is connected to the third connection end, the second end of the fourth filter resistor R4 is connected to the first end of the fifth filter capacitor C5, and the second end of the fifth filter capacitor C5 is grounded. The fourth filter resistor R4 and the fifth filter capacitor C5 form a low-pass filter, which can effectively avoid interference caused by high-frequency AC signals. Furthermore, in some embodiments, the resistance of the fourth filter resistor R4 is 1KΩ, and the capacitance value of the fifth filter capacitor C5 is 0.01uF. Of course, the user can also set the capacitance value of the fourth filter resistor R4 and the fifth filter capacitor C5 as needed, which is not limited here.

[0105] In some embodiments, the number of the temperature sensors 100 is at least three, and each temperature sensor 100 is disposed on the outer side wall of the valve and evenly distributed around the valve.

[0106] In the specific embodiment shown in FIG5 , there are three temperature sensors 100, namely a first temperature sensor 110, a second temperature sensor 120, and a third temperature sensor 130. The first temperature sensor 110 is farther from the heater rod and has a larger line resistance. Therefore, a PT1000 thermocouple 101 can be used for the first temperature sensor 110, while a PT100 thermocouple 101 can be used for the second and third temperature sensors 120, 130. The combined use of PT1000 and PT100 thermocouples can improve temperature control accuracy from the original ±1°C to ±2°C to ±0.01°C, reducing temperature measurement deviations and enabling accurate and real-time reflection of valve cavity temperature changes. This reduces the impact of temperature errors on the terminal production process and prevents the occurrence of liquefied process gas deposition. Furthermore, the temperature probe portion of the temperature sensor 100 can be made of shock-resistant and corrosion-resistant materials to extend the service life of the temperature sensor 100.

[0107] In addition, when the temperature t≤0°C, the calculation formula of the resistance R of the temperature sensor 100 is: R(t)=R0×[1+At+Bt 2 +C(t-100)t 3 ]

[0108] When the temperature t≥0°C, the resistance R of the temperature sensor 100 is calculated as follows: R(t)=R0×(1+At+Bt 2 )

[0109] Where t is the temperature of the temperature sensor 100; R(t) is the resistance of the temperature sensor 100 at temperature t; R0 is the resistance of the temperature sensor 100 at 0°C, R0 = 100Ω for PT100; R0 = 1000Ω for PT1000; A = 3.9083×10-3 ; B = -5.775 × 10 -7 ; C = -4.183 × 10 -12 Under operating conditions, the temperature sensor 100 adopts a 4-wire connection method. The resistance R of the temperature sensor 100 can be calculated based on the detected voltage and current. The resistance R of the temperature sensor 100 calculated based on the detected voltage and current is compared with the resistance R of the temperature sensor 100 calculated using the above calculation formula for the resistance R of the temperature sensor 100. If the deviation is large, it is considered that there is a problem with the resistance R of the temperature sensor 100 and maintenance is required.

[0110] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present application, and the present application is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present application, and such modifications and improvements are also considered to be within the scope of protection of the present application.

Claims

1. A temperature control method for a valve, characterized in that, Including: Determine the temperature deviation based on the current temperature and the target temperature of the valve; Determine the target voltage according to the temperature deviation; Judge whether the current voltage of the heating device is consistent with the target voltage. If not, control the voltage regulating module to adjust the voltage of the heating device according to the target voltage to obtain the adjusted voltage; Update the adjusted voltage to the new current voltage of the heating device and return to the judgment operation.

2. The temperature control method according to claim 1, wherein The determining the target voltage according to the temperature deviation includes: Determine the target voltage according to the temperature deviation using a first proportional-integral-derivative model; and / or The controlling the voltage regulating module to adjust the voltage of the heating device according to the target voltage to obtain the adjusted voltage includes: Determine the voltage regulating parameter according to the target voltage using a second proportional-integral-derivative model; Control the voltage regulating module to adjust the voltage of the heating device according to the voltage regulating parameter to obtain the adjusted voltage.

3. The temperature control method according to claim 2, wherein The determining the target voltage according to the temperature deviation further includes: Determine the adjustment parameter corresponding to the deviation range to which the temperature deviation belongs, and the adjustment parameter includes at least one of a proportional coefficient, an integral coefficient, and a differential coefficient; Update the first proportional-integral-derivative model according to the adjustment parameter; Determine the target voltage corresponding to the deviation range according to the temperature deviation and the updated first proportional-integral-derivative model.

4. The temperature control method according to claim 3, wherein There are two deviation ranges, namely a first deviation range and a second deviation range, and each temperature deviation belonging to the second deviation range is greater than each temperature deviation belonging to the first deviation range; The determining the adjustment parameter corresponding to the deviation range to which the temperature deviation belongs includes: When the temperature deviation belongs to the second deviation range, determine that the adjustment parameter includes the proportional coefficient and the differential coefficient; When the temperature deviation belongs to the first deviation range, determine that the adjustment parameter includes the integral coefficient.

5. The temperature control method according to claim 2, characterized in that, The voltage regulating module includes a thyristor, and the voltage regulating parameter is the duty ratio of the control signal of the thyristor.

6. The temperature control method according to any one of claims 1 to 5, characterized in that The valve is provided with a heating rod and a temperature sensor. The temperature sensor includes a first temperature sensor, a second temperature sensor, and a third temperature sensor. The first temperature sensor, the second temperature sensor, and the third temperature sensor are arranged on the outer surface of the valve around the valve port of the valve. The second temperature sensor and the third temperature sensor respectively correspond to both ends of the heating rod, and the first temperature sensor is located on the side of the valve port away from the heating rod; Before determining the temperature deviation based on the current temperature and the target temperature of the valve, the temperature control method further includes: Obtain the measured temperatures of the first temperature sensor, the second temperature sensor, and the third temperature sensor; Take the average value of the measured temperatures of the second temperature sensor and the third temperature sensor as the first average temperature; Take the average value of the measured temperature of the first temperature sensor and the first average temperature as the current temperature.

7. A temperature control system, characterized in that, It includes a temperature sensor, a heating device and a control device. The temperature sensor is used to measure the current temperature of the valve. Both the temperature sensor and the heating device are electrically connected to the control device. The control device controls the heating device by using the temperature control method described in any one of claims 1 to 6 to adjust the temperature of the valve.

8. The temperature control system according to claim 7, wherein The heating device is a heating rod. The temperature sensor includes a first temperature sensor, a second temperature sensor and a third temperature sensor. The temperature sensors are arranged around the valve orifice on the outer surface of the valve. The second temperature sensor and the third temperature sensor respectively correspond to both ends of the heating rod. The first temperature sensor is located on the side of the valve orifice away from the heating rod.

9. The temperature control system according to claim 7, characterized in that, The temperature sensor includes a thermocouple and four connection terminals. Among them, the first connection terminal and the second connection terminal among the four connection terminals are connected to one end of the thermocouple. The third connection terminal and the fourth connection terminal among the four connection terminals are connected to the other end of the thermocouple. The first connection terminal is used to connect a current source. The second connection terminal and the third connection terminal are respectively used to connect both ends of a pressure measuring mechanism. The fourth connection terminal is grounded.

10. The temperature control system according to claim 9, wherein The second connection terminal is connected with a first filter resistor and a first filter capacitor. The first end of the first filter resistor is connected to the second connection terminal. The second end of the first filter resistor is connected to the first end of the first filter capacitor. The second end of the first filter capacitor is grounded, and / or The third connection terminal is connected with a second filter resistor and a second filter capacitor. The first end of the second filter resistor is connected to the third connection terminal. The second end of the second filter resistor is connected to the first end of the second filter capacitor. The second end of the second filter capacitor is grounded.

11. The temperature control system according to claim 9, characterized in that, A third filter capacitor is also provided between the second connection terminal and the third connection terminal to filter out the differential mode signal between the second connection terminal and the third connection terminal.

Images