High-Precision Semiconductor Laser Current Drive and Temperature Control System Design

The design and verification of accurate temperature control system of the oven with the small or middle scale programmable logic controller (PLC) base on the dahlin algorithm is introduced. The design can achieve accurate control to the pure lag system and regulate the other logic control form the same controller. The system is cost-effective on the specific modular or instrument for the complex computing in some automatic device. Meanwhile, the design is computed and simulated by the matlab softwear for verifying the implementation. DOI: http://dx.doi.org/10.11591/telkomnika.v11i8.3101

The performance parameters and long-term operation stability of the photodetector in radiation temperature measurement will change with the change of working temperature. In order to meet the high precision temperature control demand of the photodetector, a temperature control system based on the thermoelectric refrigeration control chip ADN8831 is designed. The control system uses the thermistor as the temperature sensing element, and uses the analog proportional integral differential (PID) circuit to control the temperature closed-loop. The experimental results show that the Thermoelectric cooler (TEC) inside the photodetector can stabilize at the set temperature within 11 s under the drive of the temperature control system, and the temperature control accuracy is as low as ± 0.01 °C.

Laparoscopic surgery is a widely used minimally invasive surgery. Although using warm carbon dioxide to establish pneumoperitoneum has been demonstrated beneficial, building a high-precision and fast-response temperature control system is difficult to achieve. To this end, we propose a temperature control system for insufflator with hot and cold flow mixed. Firstly, we design the pipeline structure of the system, and the circuit hardware considering the selected components. Then, two stages, including preheating and delivery stage, are developed to improve the heating efficiency of the system, which are controlled by fuzzy logic and PID algorithm, respectively. Besides, we construct the simulation model to investigate the transfer characteristics of the heating system. Finally, a prototype of the system is developed, and experiments are performed to validate its effectiveness. The proposed system provides a feasible scheme of carbon dioxide heating for building pneumoperitoneum.

In order to ensure the measurement accuracy and long-term working stability of the laser methane sensor in the field environment such as coal mines, a design method of a high-precision double-closed-loop laser temperature control system based on the laser absorption peak and working temperature is proposed to improve the temperature control system of the DFB laser. control accuracy. Based on ADN8834 integrated TEC controller chip, the temperature control system based on PI compensation network is designed, and the simulation analysis of the temperature control system is carried out. In order to verify the accuracy and long-term working stability of the temperature control system, the laser methane sensor has passed the (-20~60)℃ high and low temperature experiment. The application of methane sensors in industrial sites such as coal mines provides technical support.

Chapter 9 - Case Study: Temperature control project

<div class="htmlview paragraph">Unique challenges arise during the design of temperature and humidity control systems (THCS) for use in microgravity. The design of the Plant Research Unit’s (PRU) THCS builds on the experience gained during the Biomass Production System (BPS) project and extends the understanding of the critical design variables and necessary technical advancements to allow for longer on-orbit operation. Previous systems have been limited by loss of prime, clogging in the porous plates and component reliability. Design of THCSs for long-duration space flight experiments requires the mitigation of these issues as well as a complete understanding of the relevant design variables. In addition to the normal design variables (e.g. mass, power, volume), a complex and interdependent relationship exists between the THCS variables including operational temperature range, operational humidity range, required humidity condensation rate and system air flow.</div>

In the RNA virus laboratory, to realize the characteristics of small temperature fluctuation and high precision in the process of RNA virus detection, a high-precision temperature control system based on a fuzzy PID temperature control algorithm is designed. The system takes MSP430 as the main controller and controls the temperature through the NTC acquisition circuit and TEC-driven circuit. The system first adopts the incremental PID algorithm for preliminary design, second determines the incremental PID parameters, and then obscures the algorithm on this basis to make it an adaptive fuzzy PID algorithm, which further improves the stability and response speed of the system. Finally, through the physical test, the incremental PID algorithm is compared with the adaptive fuzzy PID algorithm, and the design of a fuzzy PID temperature control system for RNA virus detection is realized. The test results show that the system error of the improved fuzzy PID is less than $0.2^{\circ}\mathrm{C}$, the working time is shortened by nearly 70 seconds, and has the characteristics of high precision, fast response speed, and small temperature fluctuation. Through the PID temperature control system for RNA virus detection designed, by comparison, the system has high precision and low-temperature fluctuation and can be well used in RNA virus laboratories.

With the development of science and technology in China, temperature control system has been widely used in many fields. The emergence of PLC effectively improves the shortcomings of PID control system, optimizes the performance of PID control system, and plays a very important role in promoting industrial production and construction. In view of the design of temperature control system of heating furnace, configuration software and PLC can be used the combination of technology can achieve the goal of furnace temperature control, and it can also monitor the furnace temperature in real time and comprehensively, and then adjust the furnace temperature according to the application requirements. The investment in the process is less, which can reduce the cost to a certain extent, and also has the application advantage of high accuracy. The temperature control system of electric heating furnace is designed in this paper. PLC is mainly used, and the temperature system is controlled intelligently with touch screen. According to the actual situation and cost budget, the controller of this paper chooses Mitsubishi FX2N- 48MR series PLC. In order to achieve intelligent control, it needs to use digital PID control algorithm, which is convenient for the staff to operate Gt1040-qbbd-c series touch screen is used to realize human-computer interaction. The system can be started and stopped. The touch screen for temperature setting can be very simple to operate. The temperature change can also be visually displayed and monitored, and the whole system can be automatically set.

In this article, the new method for designing the temperature control system with low vibration for a scanning tunneling microscope using dual modes heat exchanging process is proposed. The system is designed to operate into two modes i.e. the temperature control mode and the temperature stabilization mode. In the temperature control mode, the cold water is used as a heat convector in heat exchanging process. To reduce the vibration introduced by flowing of water in heat exchanging process, the cold vapor is used as a low density heat convector in the temperature stabilization mode. To assess the feasibility of the new proposed method, the preliminary experimental system is setup and verified. The experimental result of temperature control with step changed of the set-point temperature shows that temperature inside the cylindrical closed surface capsule reached the set-point value with the rise time of 25 min. The experimental result also shows that temperature stability with the fluctuation level of 0.05 °C and 0.01 °C over periods of 15 min and 2 min, respectively, are achieved. The results indicate that our goal to construct the temperature control system for a scanning tunneling microscope with temperature fluctuation of 0.01 °C over a period of 1 hour and low vibration can be realized by using the proposed method.

In this research, the design and simulation of an automatic system for temperature control using embedded system in order to automatically control of multi appliances depend on the temperature value. The appliances will be controlled are ventilation, cooling, heating and alert. This is an order to avoid or reduce to human intervention and increase system reliability. An important feature of this automation process is to reduce or eliminate the possibility of relying on the human factor operator for industries, warehouses and laboratories, and to improve working and performance environments. The system in this paper used the microcontroller PIC16F887 as the central control unit, LM35 temperature sensor as a temperature source,16x2 liquid crystal display (LCD) as indicator to display the different system working status an addition to some of drivers, relay and light emitting diodes (LED) as indicators to display the corresponding working appliance driver. The implementation and simulation of the system work has been achieved by using Proteus professional software v8.0 and mikroc pro for pic v.6.6.1 software to write the equivalent program and generate. Hex file for system working.

In industrial production, temperature and humidity are common main manipulated parameters, especially in heat treatment industry, the temperature control is becoming more and more important. This paper from two aspects that hardware and software introduced single-chip microcomputer (SCM) C8051F intelligent temperature and humidity control system, and described schematic diagram of hardware and software. The design adds the integration of carbon dioxide concentration and light intensity detection and necessary communication function. It is a more humanized and more practical intelligent temperature and humidity measurement and control system.

BACKGROUND: To maintain the required temperature range of electrical components of electric vehicles, it is necessary to use thermostating systems. The developing mathematical model of the temperature control system allows, even at the design stage of the vehicle, to determine the necessary parameters of the temperature control system, select algorithms for controlling the system, and calibrate the developed algorithm to ensure the necessary heat removal from electrical components. AIMS: Creation of a mathematical model of the electric motorcycle thermostating system, aimed at determining the potential possibilities of optimizing the system by organizing the air flow through the radiator. METHODS: The mathematical model is implemented in the AVL Cruise software environment. The characteristics of the components included in the model were obtained as a result of laboratory studies and supplemented with power equilibrium equations at the inputs and outputs, taking into account their efficiency. RESULTS: Using the developed model of the radiator of the thermostating system, the temperature graphs of the electric motor and inverter of the electric motorcycle during the driving cycle were obtained. It is noted that the applied temperature control system allows to maintain the temperature of electric components in the specified range. CONCLUSIONS: The mathematical model of the radiator of the thermostating system proposed in this paper allows to carry out calculations of the system at the stage of design of electric vehicles. The model also allows for further development in order to more fully determine the parameters of the thermostating system, including the thermal efficiency.

In view of the hysteretic nature of the heating and temperature control system with solid electric heat storage, this paper intends to control the related equipment by improved Smith predictive control method relying on the solid energy storage heating demonstration project of a university. This control method adds an additional regulator to the Smith predictive control method; in this manner, it can appropriately reduce the sensitivity of model accuracy, enhance the adaptability and effectively overcome the influence of delay on system stability, thus creating better robustness. The experimental results indicated that the temperature control accuracy could reach ±1°C.

The temperature control system is an indispensable key system for the thermal vacuum test. It is used to simulate the infrared heat flow environment of the spacecraft in orbit. In order to improve the stability and reliability of temperature control, this paper designs and develops a thermal vacuum test temperature control system based on the Modbus RTU serial communication protocol on the LabVIEW platform. The system combines the flexibility of software development on LabVIEW platform and combines the stability of serial communication with controller. This temperature control system has been used in thermal vacuum test, the control effect of overshooting within 1°C and temperature control accuracy within ±0.2°C. The system has high stability, which achieves the expected goal.

Oyster mushroom is one type of mushroom that is commonly consumed by Indonesian people which is relatively easy to cultivate. It can produce the optimum fruit body at temperatures below 30°C, the range of humidity is 60–90% with altitudes between 500–1000 meters above sea level. This paper describes on the development of the prototype of temperature and humidity control system in oyster mushroom cultivation using a fuzzy logic controller. The prototype comprises of DHT11 sensor for detecting temperature and humidity, Arduino microcontroller, mistmaker, and cooling fan. Fuzzy logic controller is installed in the Arduino microcontroller to generate an actuating signal for the mistmaker and cooling fan based on fuzzy inputs. The whole fuzzy system is designed using two inputs namely temperature and humidity with each input consist of three fuzzy sets with the triangular membership function. Meanwhile, the output variable is the speed of cooling fan with three fuzzy sets and triangular membership functions. A Mamdani inference system is adopted to achieve the control objective in the whole system. Based on the appropriate rule bases, fuzzy logic controllers are designed to produce the temperature and humidity setpoint around 27°C and 60–90 % respectively. Experimental results show the time response to achieve the setpoint span from 1 minute 27 seconds until 8 minutes 10 seconds.