A multi-path temperature control system for heating clothing and method thereof

Abstract

The application discloses a multi-path temperature control system for heating clothes and a method thereof, and relates to the technical field of temperature control.The application comprises heating clothes, heat preservation clothes, a motor and a PLC, wherein the top electric heating plate of the heating clothes, the middle-upper heating clothes, the middle-lower heating clothes and the lower heating clothes are all provided with a plurality of electric heating pieces and a plurality of temperature sensors; the heat preservation clothes are sleeved outside the heating clothes; the heating clothes are sleeved outside the motor; the heating area of the motor is divided into a top area, a middle area and a lower area; the top area, the middle area and the lower area are all provided with an electric heating plate and a plurality of temperature sensors.The application solves the temperature control precision through a fuzzy PID control algorithm, provides a preset value of the temperature setting value, and through a plurality of tests, the heating temperature variation trend of each area is investigated, the preset temperature setting value of each area is corrected, and the solid-state relay adjusts the output voltage size through chopping, so that the application has the advantages of simple structure, higher cost performance and wider application.

Description

Technical Field

[0001] This invention belongs to the field of temperature control technology, and in particular relates to a multi-channel temperature control system and method for heated clothing. For engine heating, the original method was to preheat, keep warm and cool in a constant temperature room. Now, using wearable heated clothing is a new solution and a new approach. Background Technology

[0002] The control systems of electric heating systems are mainly divided into contactor / relay control, solid-state relay control, and thyristor control.

[0003] The contactor / relay control method disconnects the circuit before reaching a certain temperature (set temperature + turn-off advance) and turns it on before reaching a certain temperature (set temperature + turn-on advance). Alternatively, it uses a segmented, superimposed approach to logically control multiple electric heating circuits, with each contactor / relay controlling one heating circuit and generating a fixed heating power. The superposition of N such heating circuits results in a sum of N heating powers. This control method is convenient to maintain, has low operating costs, and is relatively easy to control, but the entire system is cumbersome and large, and the temperature control accuracy is not high.

[0004] Solid-state relays, as contactless switching devices composed of solid-state electronic components, can achieve a turn-off frequency of up to 50Hz. The difference between solid-state relays and silicon controlled rectifiers (SCRs) lies in their operation: a solid-state relay uses a SCR plus synchronous triggering; a solid-state relay is essentially an electronic switch and cannot regulate current, while a SCR can control its conduction angle and thus regulate current magnitude. SCRs offer higher control precision but are also more expensive; solid-state relays regulate output voltage through chopping, have a simpler structure, are more cost-effective, and have wider applications. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-channel temperature control system and method for heated clothing. It solves the problem of temperature control accuracy by using a fuzzy PID control algorithm, provides preset values ​​for temperature setpoints, and conducts multiple tests to investigate the temperature change trends in each zone, thereby correcting the preset temperature setpoints for each zone. This solves the problems of existing temperature control systems being cumbersome, bulky, and having low temperature control accuracy.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] This invention relates to a multi-channel temperature control system for heated clothing, comprising a heated clothing, an insulating clothing, a motor, and a PLC. The heated clothing consists of a top electric heating plate, an upper-middle heated clothing, a lower-middle heated clothing, and a lower heated clothing. Each of the top electric heating plate, upper-middle heated clothing, lower-middle heated clothing, and lower heated clothing is equipped with multiple electric heating elements and multiple temperature sensors. The insulating clothing is worn over the heated clothing. The heated clothing is worn over the motor. The motor's heating area is divided into a top area, a middle area, and a lower area. Each of the top, middle, and lower areas is equipped with an electric heating plate and multiple temperature sensors. The temperature sensors are connected to the input terminals of the PLC. The temperature sensors are used to collect the real-time temperature of their respective sections and upload the data to the PLC. The output terminals of the PLC are connected to the electric heating plates and electric heaters, respectively. The PLC uses fuzzy PID and PWM algorithms to control the heating output power of each section of the heated clothing in real time.

[0008] As a preferred technical solution, the engine, heated clothing, and thermal insulation clothing constitute a closed system; the top electric heating plate, the upper middle heating clothing, the lower middle heating clothing, and the lower heating clothing area of ​​the heated clothing are interconnected for heat exchange.

[0009] As a preferred technical solution, the top electric heating plate uses two sets of electric heating elements; the upper middle heating garment, the lower middle heating garment, and the lower heating garment all use two sets of electric heating films.

[0010] As a preferred technical solution, the power output circuit of each group of heating elements or heating films is independent and controlled separately; in any working cycle, only one power output circuit of the two heating elements of the top electric heating plate is working.

[0011] This invention relates to a multi-channel temperature control method for heated clothing, comprising the following steps:

[0012] Step S1: Preheating. Set the preheating temperature to 50℃ via PLC. The maximum temperature overshoot of the four zones will not exceed 2℃.

[0013] Step S2: Insulation: The insulation time is controlled by PLC for five consecutive days, with a temperature control accuracy of ±1℃;

[0014] Step S3: Cooling down. The temperature is controlled by PLC to drop from 50℃ to 35℃ at a rate of 1-2℃ / hour. During the cooling process, the heated clothing needs to be reheated to maintain the cooling rate.

[0015] As a preferred technical solution, the PLC controls the heating output power of each part of the heating garment in real time through fuzzy PID algorithm and PWM algorithm.

[0016] As a preferred technical solution, the fuzzy PID algorithm includes a traditional PID control algorithm and a fuzzy control algorithm. The traditional PID control algorithm is applied to the temperature control of the insulation device. In the temperature control, the fuzzy relationship between the three parameters of the PID (P, I, D) and the error E (the difference between the temperature acquisition value and the temperature setpoint) and the error change rate Ec is continuously found. According to the determined fuzzy control rules, the three parameters of the PID are linearly adjusted to meet the different requirements of different E and Ec on the three parameters.

[0017] As a preferred technical solution, the PLC then uses a PWM algorithm to calculate a PWM output square wave from the calculated PID output, which periodically controls the on / off time and operating frequency of the solid-state relay.

[0018] As a preferred technical solution, the fuzzy control algorithm formula is as follows:

[0019]

[0020] In the formula, z0 is the precise value of the fuzzy controller output after defuzzification; z i The value of u within the domain of the fuzzy control quantity; c (z i ) for z i The membership degree value.

[0021] The present invention has the following beneficial effects:

[0022] This invention solves the temperature control accuracy problem through a fuzzy PID control algorithm, provides a preset value for the temperature setpoint, and conducts multiple sets of experiments to investigate the temperature change trend of each zone, thereby correcting the preset temperature setpoint for each zone. The solid-state relay adjusts the output voltage through chopping, resulting in a simple structure, higher cost performance, and wider application.

[0023] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a flowchart of a multi-channel temperature control method for heated clothing according to the present invention;

[0026] Figure 2 The flow chart for the fuzzy PID algorithm;

[0027] Figure 3 This is a schematic diagram of the structure of the heating garment;

[0028] Figure 4 This is a schematic diagram of the engine structure. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Please see Figure 3-4 As shown, this invention is a multi-channel temperature control system for heated clothing, including heated clothing, thermal insulation clothing, an engine, and a PLC. The heated clothing consists of a top electric heating plate 101, an upper-middle heated clothing 102, a lower-middle heated clothing 103, and a lower heated clothing 104. Each of the top electric heating plate 101, upper-middle heated clothing 102, lower-middle heated clothing 103, and lower heated clothing 104 is equipped with multiple electric heating elements and multiple temperature sensors. The thermal insulation clothing is worn over the heated clothing. The heated clothing is worn over the engine. The engine's heating area is divided into a top area 201, a middle area 202, and a lower area 203. Each of the top area 201, middle area 202, and lower area 203 is equipped with an electric heating plate and multiple temperature sensors. The temperature sensors are connected to the input terminals of the PLC. The temperature sensors are used to collect the real-time temperature of their respective areas and upload it to the PLC. The output terminals of the PLC are connected to the electric heating plates and electric heaters, respectively. The PLC uses fuzzy PID and PWM algorithms to control the heating output power of each part of the heated clothing in real time.

[0031] The engine, heated clothing, and thermal clothing form a closed system; the top electric heating plate 101, the upper middle heated clothing 102, the lower middle heated clothing 103, and the lower heated clothing 104 are interconnected for heat exchange.

[0032] The top electric heating plate 101 uses two sets of electric heating elements; the upper middle heating garment 102, the lower middle heating garment 103, and the lower heating garment 104 all use two sets of electric heating films.

[0033] Each heating element or heating film has an independent and individually controlled power output circuit; in any given working cycle, only one power output circuit of the two heating elements of the top electric heating plate 101 is in operation.

[0034] Please see Figure 1As shown, the present invention is a multi-channel temperature control method for heated clothing, comprising the following steps:

[0035] Step S1: Preheating. Set the preheating temperature to 50℃ via PLC. The maximum temperature overshoot of the four zones will not exceed 2℃.

[0036] Step S2: Insulation: The insulation time is controlled by PLC for five consecutive days, with a temperature control accuracy of ±1℃;

[0037] Step S3: Cooling down. The temperature is controlled by PLC to drop from 50℃ to 35℃ at a rate of 1-2℃ / hour. During the cooling process, the heated clothing needs to be reheated to maintain the cooling rate.

[0038] The PLC uses fuzzy PID and PWM algorithms to control the heating output power of each part of the heating garment in real time. The fuzzy PID algorithm includes both traditional PID control and fuzzy control algorithms. Traditional PID control is applied to the temperature control of the insulation device. In temperature control, the fuzzy relationship between the three PID parameters (P, I, D) and the error E (the difference between the acquired temperature value and the set temperature value) and the error change rate Ec is continuously determined. Based on the defined fuzzy control rules, the three PID parameters are linearly adjusted to meet the different requirements of E and Ec on the three parameters. The PLC then uses the calculated PID output (0-100%) to calculate a PWM output square wave (the PID control cycle is consistent with the PWM output cycle), which periodically controls the on / off time (duty cycle) and operating frequency of the solid-state relay.

[0039] The formula for the fuzzy control algorithm is:

[0040]

[0041] In the formula, z0 is the precise value of the fuzzy controller output after defuzzification; z i The value of u within the domain of the fuzzy control quantity; c (z i ) for z i The membership degree value.

[0042] Example 1

[0043] In this system, temperature sensors are installed in two locations: one on the surface of the heating element of the heated clothing, and the other on the surface of the engine casing. Based on the engine's structural type, its heating control area is divided into top, middle, and bottom sections; the bottom section is only insulated, not heated. Therefore, at the top, the electric heating plate has two temperature sensors responsible for collecting the temperature value of the top electric heating plate (average temperature value); the middle heated clothing has four temperature sensors responsible for collecting the temperature value of the middle heated clothing (average temperature value); the middle casing has six temperature sensors responsible for collecting the temperature value of the middle casing (average temperature value); the lower heated clothing has two temperature sensors responsible for collecting the temperature value of the lower heated clothing (average temperature value), and the lower casing has two temperature sensors responsible for collecting the temperature value of the lower casing (average temperature value). The composition of the temperature sensors in the insulation device is shown in the table below:

[0044]

[0045] Table 1 shows the composition of the heating garment and temperature sensor.

[0046] In this system, each heating element / film's power output circuit is independent and can be controlled individually. Specifically, for the top heating plate, only one of the two heating element power output circuits operates during any given work cycle. Before power-on, a product performance and safety check is required, including resistance and insulation resistance checks on each heating element. Only heating elements / films that pass the checks are allowed to operate. Similarly, the middle and lower heating garments operate in an alternating cycle.

[0047] Temperature sensors are responsible for collecting real-time temperatures from various parts and uploading them to the PLC. The PLC used is an S7400 PLC, model 416-2XK04-0AB0. The PLC uses a fuzzy PID algorithm + PWM algorithm to control the heating output power of each part of the heating garment in real time. During the preheating, heating, curing, and heat preservation processes in this system, the temperature setpoint is set at 50℃, and the temperature range collected by the engine housing surface temperature sensor is maintained within 50±2℃. During the cooling process of the heat preservation device, the temperature setpoint is gradually reduced according to a cooling rate of 1~2℃ / h until it reaches 35℃. The cooling rate can be set according to actual usage requirements.

[0048] Fuzzy PID algorithms include traditional PID control algorithms and fuzzy control algorithms. To better meet the control requirements of the insulation device, the control algorithm chosen is the fuzzy PID algorithm. This involves continuously identifying the fuzzy relationship between the three PID parameters (P, I, D) and the error E (the difference between the sampled temperature and the setpoint) and the error rate of change Ec during temperature control. Based on a defined fuzzy control rule, the three PID parameters are linearly adjusted to meet the different requirements of E and Ec on the three parameters. This overcomes the overshoot (including overshoot and undershoot) phenomenon that traditional PID algorithms often exhibit during rapid heating and temperature disturbances when the setpoint changes, thus achieving optimal temperature control performance. In simple terms, throughout the temperature control process, the three PID parameters (P, I, D) are no longer fixed values. Instead, they are adjusted according to different stages such as the initial heating stage, the stage approaching the setpoint, and dynamic equilibrium, selecting more suitable parameters based on the fuzzy control rule.

[0049] The PLC then uses the calculated PID output (0-100%) to calculate a PWM output square wave (the PID control cycle is consistent with the PWM output cycle), which periodically controls the on / off time (duty cycle) and operating frequency of the solid-state relay.

[0050] Example 2

[0051] A PID controller (proportional-integral-derivative controller) is a common feedback loop component in industrial control applications, consisting of a proportional unit (P), an integral unit (I), and a derivative unit (D). The basis of PID control is proportional control; integral control can eliminate steady-state error but may increase overshoot; derivative control can accelerate the response speed of large inertia systems and reduce the overshoot tendency.

[0052] Since its inception, the traditional PID controller has become a major technology in industrial control due to its advantages such as simple structure, good stability, reliable operation, and convenient adjustment. PID control is particularly convenient when the structure and parameters of the controlled object have a certain degree of uncertainty, making it impossible to establish an accurate model. While the PID control principle is simple and easy to implement, its parameter tuning is exceptionally complex. For the speed control system of a vehicle, because it is a time-varying nonlinear system requiring different PID parameters at different times, it is difficult to achieve good operating results throughout the entire process using a traditional PID controller.

[0053] like Figure 2As shown, fuzzy PID control utilizes fuzzy logic and certain fuzzy rules to optimize PID parameters in real time, overcoming the limitation of traditional PID control which cannot adjust parameters in real time. Fuzzy PID control includes fuzzification, determining fuzzy rules, and defuzzification. The car collects track information through sensors, determines the current deviation E from the track centerline and the change ec between the current and previous deviations, performs fuzzy inference based on given fuzzy rules, and finally defuzzifies the fuzzy parameters to output the PID control parameters.

[0054] The fuzzy controller mainly consists of three modules: fuzzification, fuzzy inference, and declarative analysis. First, our heated clothing collects temperature-related data, such as from the heating plate. This data is processed by an algorithm to obtain two values: the deviation from the centerline (E) and the change (difference) between the current and previous deviations (EC). (This algorithm uses 2D input; similarly, it can use 1D or 3D input, but 2D is more suitable for the heating plate.) For example, if the heating plate temperature is currently 50 degrees Celsius, and the previous temperature was 43 degrees Celsius, then E is 50, and EC is 50 - 43 = 7.

[0055] Next, we need to fuzzify these two values. Let's take E as an example. The E value collected by the temperature sensor has a range, meaning the deviation from the midline is within a feasible interval. Here, we assume this interval is -80 to 80, meaning the maximum distance the monitored temperature deviates from the midline is 80, with positive and negative indicating left or right. We further assume the feasible range for the rate of change of the midline deviation is -50 to +50.

[0056] Next, we need to fuzzify these two values. We divide the interval of E (-80 to 80) into eight parts: -80 to -60, -60 to -40, -40 to -20, -20 to 0, 0 to 20, 20 to 40, 40 to 60, and 60 to 80. Then, we represent -60, -40, -20, 0, 20, 40, and 60 using NB, NM, NS, ZO, PS, PM, and PB respectively (N can be understood as negative, P as positive, B as big, M as middle, S as small, and ZO as zero). For example, when E = 50, E belongs to the interval between PM and PB, and E in this case will have 2 (or 1) membership degrees. The percentage of E belonging to PM(40) is (60-50) / (60-40) = 1 / 2, and similarly, the percentage belonging to PB(60) is (50-40) / (60-40) = 1 / 2. This means that 40 to 60 is linearly segmented, and E belongs more closely to either PM or PB (when the output value E is greater than 60 (PB), the membership degree is 1, and the membership value is PB, meaning E completely belongs to PB; the same applies when E is less than -60 (NB)). Similarly, EC can also be fuzzed.

[0057] It is worth noting that the various units included in the above system embodiments are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be achieved; in addition, the specific names of each functional unit are only for easy differentiation and are not used to limit the scope of protection of the present invention.

[0058] Furthermore, those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware, and the corresponding program can be stored in a computer-readable storage medium.

[0059] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A multi-channel temperature control system for heated clothing, comprising heated clothing, thermal insulation clothing, a motor, and a PLC, characterized in that: The heated clothing consists of a top electric heating plate (101), an upper middle heated clothing (102), a lower middle heated clothing (103), and a lower heated clothing (104); the top electric heating plate (101), the upper middle heated clothing (102), the lower middle heated clothing (103), and the lower heated clothing (104) are all equipped with multiple electric heating elements and multiple temperature sensors; The thermal insulation garment is worn over the heating garment; The heating garment is fitted over the outside of the engine; the heating area of ​​the engine is divided into a top area (201), a middle area (202) and a lower area (203); each of the top area (201), the middle area (202) and the lower area (203) is equipped with an electric heating plate and multiple temperature sensors; The temperature sensor is connected to the input terminal of the PLC; the temperature sensor is used to collect the real-time temperature of the part it is located in and upload it to the PLC. The output terminals of the PLC are connected to the electric heating plate and the electric heating element respectively; the PLC controls the heating output power of each part of the heating garment in real time through fuzzy PID algorithm and PWM algorithm.

2. A multi-channel temperature control system for heated clothing according to claim 1, characterized in that, The engine, heating garment, and thermal insulation garment constitute a closed system; the top electric heating plate (101), upper middle heating garment (102), lower middle heating garment (103), and lower heating garment (104) of the heating garment are interconnected for heat exchange.

3. A multi-channel temperature control system for heated clothing according to claim 2, characterized in that, The top electric heating plate (101) uses two sets of electric heating elements; the upper middle heating garment (102), the lower middle heating garment (103) and the lower heating garment (104) all use two sets of electric heating films.

4. A multi-channel temperature control system for heated clothing according to claim 3, characterized in that, Each heating element or heating film has an independent and individually controlled power output circuit; in any given working cycle, only one power output circuit of the two heating elements of the top electric heating plate (101) is in operation.

5. The control method for a multi-channel temperature control system for heated clothing according to claim 4, characterized in that, Includes the following steps: Step S1: Preheating. Set the preheating temperature to 50℃ via PLC. The maximum temperature overshoot of the four zones will not exceed 2℃. Step S2: Insulation: The insulation time is controlled by PLC for five consecutive days, with a temperature control accuracy of ±1℃; Step S3: Cooling down. The temperature is controlled by PLC to drop from 50℃ to 35℃ at a rate of 1-2℃ / hour. During the cooling process, the heated clothing needs to be reheated to maintain the cooling rate.

6. The control method according to claim 5, characterized in that, The PLC uses fuzzy PID and PWM algorithms to control the heating output power of each part of the heating garment in real time.

7. The control method according to claim 6, characterized in that, The fuzzy PID algorithm includes a traditional PID control algorithm and a fuzzy control algorithm. The traditional PID control algorithm is applied to the temperature control of the insulation device. In the temperature control, the fuzzy relationship between the three parameters of the PID (P, I, D) and the error E (the difference between the temperature acquisition value and the temperature setpoint) and the error change rate Ec is continuously found. According to the determined fuzzy control rules, the three parameters of the PID are linearly adjusted to meet the different requirements of different E and Ec on the three parameters.

8. The control method according to claim 5, characterized in that, The PLC then uses the calculated PID output to calculate a PWM output square wave through a PWM algorithm, which periodically controls the on / off time and operating frequency of the solid-state relay.

9. The control method according to claim 7, characterized in that, The formula for the fuzzy control algorithm is: ； In the formula, The output of the fuzzy controller is the precise value after defuzzification; The value is within the domain of the fuzzy control quantity; for The membership degree value.

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