Semiconductor wafer factory crown block track distributed over-temperature detection system and method

Abstract

The invention discloses a semiconductor wafer factory crown block track distributed over-temperature detection system and method, and relates to the technical field of temperature detection. The system comprises a temperature detection module, a current detection loop module, a control decision module, an execution and alarm module and a power supply module. An insulating double-core temperature sensing line of the temperature detection module is laid and fixed along a crown block track, temperature abnormity is converted into a physical electrical signal, the physical electrical signal is converted into a voltage signal by the current detection loop module and then transmitted to the control decision module, digital filtering processing and comparison are carried out, and the working state of the system is judged based on logic of a state machine. And outputting a control signal to the execution and alarm module. According to the invention, continuous linear monitoring of the crown block track temperature is realized by using the insulated double-core temperature sensing wire, a safety blind area is thoroughly eliminated, irreversible physical fusing is used as an alarm signal, and the anti-interference performance and the reliability are high. According to the scheme, on-demand work can be achieved, and meanwhile good expandability and compatibility are achieved.

Description

Technical Field

[0001] This invention relates to the field of temperature detection technology, and more particularly to a distributed over-temperature detection system and method for overhead crane tracks in semiconductor wafer fabs. Background Technology

[0002] In semiconductor wafer fabs, overhead crane tracks operate under heavy loads and high speeds for extended periods, resulting in intense friction between the wheels and tracks. This can easily lead to abnormally high localized temperatures on the tracks. Overheating can cause equipment malfunctions such as track deformation and accelerated wheel wear. Therefore, real-time and reliable monitoring and protection of overhead crane track temperatures are essential for ensuring safe production. Currently, monitoring overhead crane track temperatures primarily relies on the following technical solutions:

[0003] 1. Manual periodic inspection and handheld thermometer measurement: This is the most traditional method for detecting the temperature of overhead crane tracks in semiconductor wafer fabs. Maintenance personnel periodically use handheld devices such as infrared thermometers to measure the temperature at specific points on the track. The disadvantages and reasons for this method include: 1) Non-real-time: It cannot achieve 24-hour continuous monitoring; temperature anomalies occurring during inspection intervals cannot be detected in time, resulting in a significant safety gap; 2) Incomplete and inefficient: Measurements can only be taken at a limited number of preset points, failing to cover the entire track and easily missing localized overheating areas between monitoring points. Furthermore, manual inspection is time-consuming, labor-intensive, and costly; 3) Inability to achieve automatic linkage: Even if overheating is detected, it relies on manual reporting and operation, resulting in a slow response and inability to achieve rapid automatic power-off protection in emergency situations.

[0004] 2. Fixed-mount point temperature sensors: Track temperature detection is achieved by installing multiple thermocouples, RTDs, or digital temperature sensors (such as DS18B20) at fixed intervals along the track. The disadvantages and reasons for this method include: 1) Inevitable monitoring blind spots: Although an improvement over manual inspection, it is essentially still discrete-point monitoring. The area between sensors (usually several meters to tens of meters) becomes a monitoring blind spot; if local overheating occurs within this blind spot, the system will completely fail. The denser the sensor deployment, the higher the cost and the more complex the wiring; 2) Complex installation and maintenance, significant reliability challenges: Each sensor requires an independent power supply, signal line, and protective sleeve, resulting in a huge workload for installation and maintenance on long-distance, high-vibration tracks. Sensors and their wiring are easily damaged under harsh conditions, leading to a high single-point failure rate; 3) High system cost and poor scalability: Achieving full coverage requires a large number of sensors, resulting in high total cost and a complex system architecture, hindering large-scale deployment.

[0005] 3. Infrared Thermal Imaging Online Monitoring System: An infrared thermal imager is installed along the track or on the crane body to scan and image the track. The disadvantages and reasons for this method include: 1) Extremely high cost: High-precision infrared thermal imagers suitable for long-distance temperature measurement are expensive and usually require a pan-tilt unit, complex image analysis server, and software, resulting in very high initial investment and maintenance costs; 2) Poor environmental adaptability: Its measurement accuracy is easily affected by environmental moisture, dust, and smoke. In typical application scenarios such as steel plants and ports, the lens is easily contaminated, leading to blurred images or inaccurate temperature measurements, making reliability difficult to guarantee; 3) Inability to achieve direct and reliable linkage: The system is complex, with a long chain from image analysis to issuing alarm commands, and it is usually an independent monitoring layer, making it difficult to achieve simple, hard-wired emergency power-off linkage with the crane's underlying electrical control system.

[0006] In summary, how to achieve blind-spot-free, real-time, highly reliable temperature monitoring of operating components such as overhead crane tracks in long-distance, linear, and harsh environments, and which can directly drive safety protection actions, at a reasonable cost, has become an urgent problem to be solved in this field. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention proposes a distributed over-temperature detection system and method for overhead crane tracks in semiconductor wafer fabs. The temperature detection module's insulated dual-core temperature sensing wire is laid and fixed along the overhead crane track. Temperature anomalies are converted into physical electrical signals, which are then converted into voltage signals by a current detection loop module and transmitted to the control decision module. After digital filtering and comparison, the system's operating state is determined based on state machine logic, and control signals are output to the execution and alarm modules. This invention enables continuous linear monitoring of overhead crane track temperature, features a simple structure, high reliability, and strong scalability and compatibility.

[0008] A distributed over-temperature detection system for overhead crane tracks in a semiconductor wafer fab, characterized by comprising the following modules:

[0009] The temperature detection module uses an insulated double-core temperature sensing wire as the detection element to detect the temperature of the crane track in real time and convert temperature anomalies into physical and electrical signals.

[0010] The current detection loop module is electrically connected to the temperature detection module and is used to continuously monitor the electrical status of the temperature detection module and output the detection results as a voltage signal to the execution control module. The current detection loop module contains two current detection loops, each consisting of a current transformer, a current sampling resistor, an active rectifier circuit, and an RC filter circuit.

[0011] The control decision module, including an STM32F103RCT6 microcontroller, is used to receive the output voltage signal from the current detection loop module, digitally filter the acquired voltage signal, change the state of the state machine according to the signal processing result, and output the control signal to the execution and alarm module.

[0012] The execution and alarm module, including the overhead crane main power cabinet relay control circuit and status indicator control circuit, is used to receive control signals output by the control decision module and control the overhead crane power supply, key control circuits and status indicators according to the fault signals.

[0013] The power supply module is used to provide stable power to each module.

[0014] Furthermore, the insulated dual-core temperature sensing wire of the temperature detection module consists of two parallel metal conductors, with the metal conductors covered by a layer of thermoplastic insulating material with a specific melting temperature. The insulated dual-core temperature sensing wire is laid and fixed along the entire length of the overhead crane track, either close to or parallel to the side or bottom of the track. The length of the insulated dual-core temperature sensing wire is cut and laid according to the actual length of the overhead crane track. For overhead crane tracks of different lengths, insulated dual-core temperature sensing wires of appropriate lengths are selected or customized. The metal conductors are made of aluminum.

[0015] Furthermore, the thermoplastic insulation material of the insulated dual-core temperature sensing wire is a thermoplastic polymer. When the ambient temperature at any position of the insulated dual-core temperature sensing wire reaches or exceeds the rated melting temperature of the thermoplastic insulation material, the thermoplastic insulation material at that point melts, and the two conductors short-circuit at that point.

[0016] Furthermore, the current detection circuit module includes two symmetrically arranged current detection circuits. Each current detection circuit consists of a current transformer, a sampling resistor, an active rectifier circuit, and a filter circuit, used to detect the current in the two metal conductors of the insulated double-core temperature sensing wire and output the corresponding voltage signal V. O1 and V O2 To the control decision module.

[0017] Furthermore, the state machine of the microcontroller in the control decision module is configured with three states: waiting, running, and fault. When there is no current in the crane track, the state machine operates in the waiting state, and the control decision module does not output control signals. When the crane track is energized, V... O1 When the sampled value is greater than the given start value, the state machine operates in the running state, and the control decision module outputs a fault-free signal to the execution and alarm module; in V O1 The sampled value is greater than the given start value and V O1 and V O2 The absolute value of the difference is less than 0.1 times V. O1When sampling values ​​are obtained, the state machine operates in a fault state, and the control decision module outputs a fault signal to the execution and alarm module; the starting value depends on the system noise and the threshold of the induced voltage coupled from other crane tracks when the crane track is powered off.

[0018] Furthermore, when the execution and alarm module receives a fault signal, the control circuit drives the relay to immediately disconnect, cutting off the main power supply of the crane or the key control circuit to achieve forced power-off protection, and at the same time, drives the status indicator to issue an alarm; when the execution and alarm module receives a no-fault signal, drives the status indicator to operate normally.

[0019] Furthermore, the insulated dual-core temperature sensing wire of the temperature detection module uses a current-limiting measure to limit the current Icom at the common terminal of the insulated dual-core temperature sensing wire to within 2A. This current-limiting measure involves selecting one of the two current detection circuits as the current detection circuit for the common terminal, and connecting a current-limiting capacitor Clim in series in the common circuit of this current detection circuit. The expression for the current-limiting capacitor Clim is:

[0020]

[0021] Where E is the induced voltage across the current detection circuit, L is the equivalent inductance across the current detection circuit, and R is the equivalent resistance across the current detection circuit.

[0022] In addition, this application also proposes a distributed over-temperature detection method for overhead crane tracks in semiconductor wafer fabs, comprising the following steps:

[0023] Step S1: Lay and fix the insulated double-core temperature sensing wire of the temperature detection module along the entire length of the crane track, close to or parallel to the side or bottom of the track. Connect the two leads of the insulated double-core temperature sensing wire to the two current detection circuit input terminals of the signal conversion module, and complete the electrical connection between each module.

[0024] Step S2: After the crane starts, the crane track is energized and generates an alternating magnetic field. The insulated double-core temperature sensing wire of the temperature detection module generates an induced current. The two metal conductors transmit the induced current signal to the two current detection circuits of the signal conversion module respectively. When the temperature of the crane track is within the normal range, the two temperature sensing wires remain intact. When the temperature of the crane track at a certain point exceeds the rated melting temperature of the thermoplastic insulation material, the thermoplastic insulation material at that point melts, and the two conductors short-circuit at that point.

[0025] Step S3: The current detection circuit of the current detection circuit module couples the induced current signal through a current transformer, converts it into a voltage signal through a current sampling resistor, and then converts the AC signal into a DC signal through an active rectifier circuit and an RC filter circuit, outputting the voltage signal V corresponding to the first metal conductor. O1 and the corresponding second metal conductor VO2 The voltage signal is sent to the control decision module;

[0026] Step S4: The control decision module receives the voltage signal V. O1 V O2 The signals are digitally filtered and then compared to determine the system's operating state based on state machine logic.

[0027] When there is no current in the crane track, the state machine operates in a waiting state, and the control decision module does not output control signals;

[0028] When the overhead crane track is energized, V O1 When the sampled value is greater than the given start value, the state machine operates in the running state, and the control decision module outputs a fault-free signal to the execution and alarm module.

[0029] When the overhead crane track is energized, at V O1 The sampled value is greater than the given start value and V O1 and V O2 The absolute value of the difference is less than 0.1 times V. O1 When sampling values, the state machine operates in a fault state, and the control decision module outputs a fault signal to the execution and alarm module;

[0030] Step S5: When the execution and alarm module receives a fault signal, the control circuit drives the relay to immediately disconnect, cutting off the main power supply of the crane or the critical control circuit to achieve forced power failure protection. At the same time, the drive status indicator light emits an alarm. When the execution and alarm module receives a no-fault signal, the drive status indicator light operates normally.

[0031] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0032] (1) The semiconductor wafer fab overhead crane track distributed over-temperature detection system and method disclosed in this invention realizes seamless monitoring of the entire line and completely eliminates safety blind spots: by continuously laying temperature sensing lines along the entire length of the track, the traditional discrete point monitoring is transformed into continuous line monitoring, ensuring that overheating at any point on the track can be detected instantly, fundamentally solving the problem of monitoring blind spots caused by the spacing of sensor points in the prior art.

[0033] (2) This invention pioneers an irreversible physical melting alarm mechanism, which is highly reliable and adaptable to various environments: it uses the irreversible physical melting of the insulation layer of the temperature sensing wire at a set temperature as an alarm signal. This mechanism is simple and direct, and is not affected by electronic device drift, software crashes, or electromagnetic interference. Its inherent reliability far exceeds that of complex systems based on electronic sensors.

[0034] (3) The present invention designs an intelligent logic of "monitoring while running and hibernation while stopped": cleverly utilizing the induced current generated when the track is energized as a detection signal source. The system automatically activates monitoring only when the track is energized and the crane is running (i.e., when there is a risk of overheating); it automatically goes into hibernation when stopped. It achieves on-demand operation, logical self-consistency, and requires no additional power supply or control lines.

[0035] (4) This invention has strong scalability and compatibility, and provides a data foundation for predictive maintenance: the system can be added to the existing overhead crane system as an independent safety layer without modifying the core control system of the overhead crane. It is flexible in deployment, compatible with new and old equipment, and conducive to technical transformation and promotion in existing factories. By recording and analyzing the location and frequency of historical melting points, areas with uneven track wear or concentrated mechanical stress can be indirectly assessed, providing valuable decision-making references for the preventive maintenance of equipment. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab, as proposed in this invention.

[0037] Figure 2 This is a schematic diagram of the insulated dual-core temperature sensing wire of the temperature detection module of the present invention before it melts.

[0038] Figure 3 This is a schematic diagram of the insulated dual-core temperature sensing wire of the temperature detection module of the present invention after it has melted.

[0039] Figure 4 This is the current detection circuit of the current detection circuit module of the present invention.

[0040] Figure 5 This is a schematic diagram of the microcontroller used in the control decision module of this invention.

[0041] Figure 6 This is the equivalent model of the track over-temperature detection circuit before it melts in this invention.

[0042] Figure 7 This is an equivalent model of the track over-temperature detection circuit after it melts in this invention.

[0043] in, Figure 4 In this context, CT stands for current transformer, Rcs is the current sampling resistor, and V... O This is the output voltage signal; Figure 6 In this context, Icom represents the current at the common terminal of the insulated dual-core circuit, Clim represents the current-limiting capacitor, Cs represents the equivalent parasitic capacitance between the two temperature sensing wires, and Iline represents the induced current. Detailed Implementation

[0044] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. The technical solutions in the embodiments of the present invention will be clearly and completely described. 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.

[0045] like Figure 1 As shown, a distributed over-temperature detection system for overhead crane tracks in a semiconductor wafer fab is characterized by comprising the following modules:

[0046] The temperature detection module uses an insulated double-core temperature sensing wire as the detection element to detect the temperature of the crane track in real time and convert temperature anomalies into physical and electrical signals.

[0047] The current detection loop module is electrically connected to the temperature detection module and is used to continuously monitor the electrical status of the temperature detection module and output the detection results as a voltage signal to the execution control module. The current detection loop module contains two current detection loops, each consisting of a current transformer, a current sampling resistor, an active rectifier circuit, and an RC filter circuit.

[0048] The control decision module, including an STM32F103RCT6 microcontroller, is used to receive the output voltage signal from the current detection loop module, digitally filter the acquired voltage signal, change the state of the state machine according to the signal processing result, and output the control signal to the execution and alarm module.

[0049] The execution and alarm module, including the overhead crane main power cabinet relay control circuit and status indicator control circuit, is used to receive control signals output by the control decision module and control the overhead crane power supply, key control circuits and status indicators according to the fault signals.

[0050] The power supply module is used to provide stable power to each module.

[0051] Furthermore, such as Figure 2 As shown, the insulated dual-core temperature sensing wire of the temperature detection module consists of two parallel metal conductors. The metal conductors are covered with a layer of thermoplastic insulating material with a specific melting temperature. The insulated dual-core temperature sensing wire is laid and fixed along the entire length of the overhead crane track, either close to or parallel to the side or bottom of the track. The metal conductors are made of aluminum, achieving the lowest cost and lightest weight while meeting the core function of transmitting "on / off" signals.

[0052] In practical applications, the length of the insulated dual-core temperature sensing wire can be cut and laid according to the actual length of the track to be monitored. For tracks of different lengths, only temperature sensing wires of corresponding lengths need to be selected or customized, while the circuit parameters of the current detection loop module (such as the capacitance value of the current-limiting capacitor Clim) can be pre-configured or slightly adjusted according to the approximate length range of the temperature sensing wire, while the core detection algorithm remains unchanged. The current detection loop module and the control decision module determine faults by monitoring the current difference, giving them inherent robustness to changes in loop reference parameters caused by length variations.

[0053] Furthermore, such as Figure 3 As shown, the thermoplastic insulation material of the insulated double-core temperature sensing wire is a low-melting-point thermoplastic polymer. When the ambient temperature at any position of the insulated double-core temperature sensing wire reaches or exceeds the rated melting temperature of the thermoplastic insulation material, the thermoplastic insulation material at that point melts, and the two conductors short-circuit at that point.

[0054] Low-melting-point thermoplastic polymers possess precise and stable melting point characteristics, reliably melting or shrinking upon reaching a set temperature, thereby short-circuiting the two aluminum conductors and triggering an accurate alarm signal. The specific low-melting-point thermoplastic polymer selected depends on the preset track trigger protection temperature;

[0055] In a specific embodiment of the present invention, the insulation layer of the temperature sensing wire selected has a melting temperature of 86°C, considering that:

[0056] (1) Exceeding the maximum daily ambient temperature and normal equipment operating temperature: Semiconductor wafer manufacturing workshops are usually equipped with strict clean temperature control systems, and their ambient temperature is precisely maintained within the range of approximately 22°C ± 2°C. Even when the equipment is generating heat during normal operation, it is extremely rare for the temperature to remain stable above 86°C for an extended period. Therefore, under normal operating conditions, changes in ambient temperature are unlikely to reach or approach the melting threshold, thus eliminating the possibility of the temperature sensing wire accidentally melting due to fluctuations in ambient temperature.

[0057] (2) Below the ignition point or damage temperature of critical materials: The ignition point or the temperature at which many materials such as cables and plastics begin to release toxic gases is in the hundreds of degrees. Setting 86°C in the “early overheating stage”, which is far below these dangerous temperatures, provides a valuable time window for personnel response and early intervention.

[0058] Furthermore, the current detection circuit module includes two symmetrically arranged current detection circuits, each current detection circuit as follows: Figure 4 The circuit shown consists of a current transformer, a sampling resistor, an active rectifier circuit, and a filter circuit. It is used to detect the current in the two metal conductors of the insulated double-core temperature sensing wire and output the corresponding voltage signal V. O1 and V O2 To the control decision module.

[0059] Furthermore, the state machine of the microcontroller in the control decision module is configured with three states: waiting, running, and fault. When there is no current in the crane track, the state machine operates in the waiting state, and the control decision module does not output control signals. When the crane track is energized, V... O1 When the sampled value is greater than the given start value, the state machine operates in the running state, and the control decision module outputs a fault-free signal to the execution and alarm module; in V O1 The sampled value is greater than the given start value and V O1 and V O2 The absolute value of the difference is less than 0.1 times V. O1 When sampling values, the state machine operates in a fault state, and the control decision module outputs a fault signal to the execution and alarm module; the microcontroller is... Figure 5 As shown.

[0060] Since the two independent current detection circuits are fully connected in parallel after the insulation layer of the temperature sensing wire completely melts, the absolute value of the difference between the sampled values ​​of Vo1 and Vo2 should be 0. However, considering the accuracy of the sampling circuit resistor, the reverse recovery time of the switching diode in the active rectifier circuit, and the gain and bandwidth of the operational amplifier, the threshold for switching the state machine to the fault state is set to 0.1 times the sampled value of Vo1 to ensure that the state machine can reliably switch when the insulation layer of the temperature sensing wire melts.

[0061] Regarding the determination of the starting value, an experimentally determined value slightly higher than the system noise and the induced voltage threshold coupled from other crane tracks when the crane track is de-energized is generally set to 0.1 times the Iline1 sampling value under operating conditions.

[0062] Furthermore, when the execution and alarm module receives a fault signal, the control circuit drives the relay to immediately disconnect, cutting off the main power supply of the crane or the key control circuit to achieve forced power-off protection, and at the same time, drives the status indicator to issue an alarm; when the execution and alarm module receives a no-fault signal, drives the status indicator to operate normally.

[0063] Furthermore, the equivalent models of the track over-temperature detection circuit before and after the fuse is broken are as follows: Figure 6 and Figure 7 As shown, in a specific embodiment of the present invention, the temperature sensing wire diameter is 0.64mm, the melting temperature of the insulation layer is 86 degrees Celsius, and the insulated double-core temperature sensing wire of the temperature detection module limits the current Icom at the common terminal of the insulated double-core temperature sensing wire to within 2A through current limiting measures. The current limiting measure involves selecting one of the two current detection circuits as the current detection circuit where the common terminal is located, and connecting a current limiting capacitor Clim in series in the common circuit of this current detection circuit. The expression for the current limiting capacitor Clim is:

[0064]

[0065] Where E is the induced voltage across the current detection circuit, L is the equivalent inductance across the current detection circuit, and R is the equivalent resistance across the current detection circuit. Because of the parasitic capacitance Cs, the common terminal current Icom is larger than the theoretically calculated value; therefore, the capacitive reactance of the current-limiting capacitor Clim is also larger than the theoretically calculated value.

[0066] In addition, this application also proposes a distributed over-temperature detection method for overhead crane tracks in semiconductor wafer fabs, comprising the following steps:

[0067] Step S1: Lay and fix the insulated double-core temperature sensing wire of the temperature detection module along the entire length of the crane track, close to or parallel to the side or bottom of the track. Connect the two leads of the insulated double-core temperature sensing wire to the two current detection circuit input terminals of the signal conversion module, and complete the electrical connection between each module.

[0068] Step S2: After the crane starts, the crane track is energized and generates an alternating magnetic field. The insulated double-core temperature sensing wire of the temperature detection module generates an induced current. The two metal conductors transmit the induced current signal to the two current detection circuits of the signal conversion module respectively. When the temperature of the crane track is within the normal range, the two temperature sensing wires remain intact. When the temperature of the crane track at a certain point exceeds the rated melting temperature of the thermoplastic insulation material, the thermoplastic insulation material at that point melts, and the two conductors short-circuit at that point.

[0069] Step S3: The current detection circuit of the current detection circuit module couples the induced current signal through a current transformer, converts it into a voltage signal through a current sampling resistor, and then converts the AC signal into a DC signal through an active rectifier circuit and an RC filter circuit, outputting the voltage signal V corresponding to the first metal conductor. O1 and the corresponding second metal conductor V O2 The voltage signal is sent to the control decision module;

[0070] Step S4: The control decision module receives the voltage signal V. O1 V O2 The signals are digitally filtered and then compared to determine the system's operating state based on state machine logic.

[0071] When there is no current in the crane track, the state machine operates in a waiting state, and the control decision module does not output control signals;

[0072] When the overhead crane track is energized, V O1 When the sampled value is greater than the given start value, the state machine operates in the running state, and the control decision module outputs a fault-free signal to the execution and alarm module.

[0073] When the overhead crane track is energized, at V O1 The sampled value is greater than the given start value and VO1 and V O2 The absolute value of the difference is less than 0.1 times V. O1 When sampling values, the state machine operates in a fault state, and the control decision module outputs a fault signal to the execution and alarm module;

[0074] Step S5: When the execution and alarm module receives a fault signal, the control circuit drives the relay to immediately disconnect, cutting off the main power supply of the crane or the critical control circuit to achieve forced power failure protection. At the same time, the drive status indicator light emits an alarm. When the execution and alarm module receives a no-fault signal, the drive status indicator light operates normally.

[0075] The above descriptions are merely preferred embodiments of this application, and the present invention is not limited to the above embodiments. It is understood that other improvements and variations directly derived or conceived by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included within the protection scope of the present invention.

Claims

1. A distributed over-temperature detection system for overhead crane tracks in a semiconductor wafer fab, characterized in that, Includes the following modules: The temperature detection module uses an insulated double-core temperature sensing wire as the detection element to detect the temperature of the crane track in real time and convert temperature anomalies into physical and electrical signals. The current detection loop module is electrically connected to the temperature detection module and is used to continuously monitor the electrical status of the temperature detection module and output the detection results as a voltage signal to the execution control module. The current detection loop module contains two current detection loops, each consisting of a current transformer, a current sampling resistor, an active rectifier circuit, and an RC filter circuit. The control decision module, including an STM32F103RCT6 microcontroller, is used to receive the output voltage signal from the current detection loop module, digitally filter the acquired voltage signal, change the state of the state machine according to the signal processing result, and output the control signal to the execution and alarm module. The execution and alarm module, including the overhead crane main power cabinet relay control circuit and status indicator control circuit, is used to receive control signals output by the control decision module and control the overhead crane power supply, key control circuits and status indicators according to the fault signals. The power supply module is used to provide stable power to each module.

2. The distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab according to claim 1, characterized in that, The temperature detection module's insulated dual-core temperature sensing wire consists of two parallel metal conductors, each covered with a layer of thermoplastic insulating material with a specific melting temperature. The insulated dual-core temperature sensing wire is laid and fixed along the entire length of the overhead crane track, either close to or parallel to the side or bottom of the track. The length of the insulated dual-core temperature sensing wire is cut and laid according to the actual length of the overhead crane track. For overhead crane tracks of different lengths, insulated dual-core temperature sensing wires of appropriate lengths are selected or customized. The metal conductors are made of aluminum.

3. The distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab according to claim 1, characterized in that, The thermoplastic insulation material of the insulated double-core temperature sensing wire is a thermoplastic polymer. When the ambient temperature at any position of the insulated double-core temperature sensing wire reaches or exceeds the rated melting temperature of the thermoplastic insulation material, the thermoplastic insulation material at that point melts, and the two conductors short-circuit at that point.

4. The distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab according to claim 1, characterized in that, The current detection circuit module includes two symmetrically arranged current detection circuits. Each current detection circuit consists of a current transformer, a sampling resistor, an active rectifier circuit, and a filter circuit, used to detect the current in the two metal conductors of the insulated double-core temperature sensing wire and output the corresponding voltage signal V. O1 and V O2 To the control decision module.

5. The distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab according to claim 1, characterized in that, The state machine of the microcontroller in the control decision module is configured with three states: waiting, running, and fault. When there is no current in the crane track, the state machine operates in the waiting state, and the control decision module does not output control signals. When the crane track is energized, V... O1 When the sampled value is greater than the given start value, the state machine operates in the running state, and the control decision module outputs a fault-free signal to the execution and alarm module; in V O1 The sampled value is greater than the given start value and V O1 and V O2 The absolute value of the difference is less than 0.1 times V. O1 When sampling values ​​are obtained, the state machine operates in a fault state, and the control decision module outputs a fault signal to the execution and alarm module; the starting value depends on the system noise and the threshold of the induced voltage coupled from other crane tracks when the crane track is powered off.

6. The distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab according to claim 1, characterized in that, When the execution and alarm module receives a fault signal, the control circuit drives the relay to immediately disconnect, cutting off the main power supply of the crane or the key control circuit to achieve forced power failure protection, and at the same time, the drive status indicator light emits an alarm; when the execution and alarm module receives a no-fault signal, the drive status indicator light operates normally.

7. The distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab according to claim 1, characterized in that, The temperature detection module uses a current-limiting measure to limit the current Icom at the common terminal of the insulated dual-core temperature sensing wire to within 2A. This current-limiting measure involves selecting one of the two current detection circuits as the common terminal current detection circuit, and connecting a current-limiting capacitor Clim in series in the common circuit of this current detection circuit. The expression for the current-limiting capacitor Clim is: Where E is the induced voltage across the current detection circuit, L is the equivalent inductance across the current detection circuit, and R is the equivalent resistance across the current detection circuit.

8. A distributed over-temperature detection method for overhead crane tracks in a semiconductor wafer fab, characterized in that, The distributed over-temperature detection method for the overhead crane track in a semiconductor wafer fab is applied to the distributed over-temperature detection system for the overhead crane track in a semiconductor wafer fab as described in any one of claims 1-7. The distributed over-temperature detection method for the overhead crane track in a semiconductor wafer fab includes the following steps: Step S1: Lay and fix the insulated double-core temperature sensing wire of the temperature detection module along the entire length of the crane track, close to or parallel to the side or bottom of the track. Connect the two leads of the insulated double-core temperature sensing wire to the two current detection circuit input terminals of the signal conversion module, and complete the electrical connection between each module. Step S2: After the crane starts, the crane track is energized and generates an alternating magnetic field. The insulated double-core temperature sensing wire of the temperature detection module generates an induced current. The two metal conductors transmit the induced current signal to the two current detection circuits of the signal conversion module respectively. When the temperature of the crane track is within the normal range, the two temperature sensing wires remain intact. When the temperature of the crane track at a certain point exceeds the rated melting temperature of the thermoplastic insulation material, the thermoplastic insulation material at that point melts, and the two conductors short-circuit at that point. Step S3: The current detection circuit of the current detection circuit module couples the induced current signal through a current transformer, converts it into a voltage signal through a current sampling resistor, and then converts the AC signal into a DC signal through an active rectifier circuit and an RC filter circuit, outputting the voltage signal V corresponding to the first metal conductor. O1 and the corresponding second metal conductor V O2 The voltage signal is sent to the control decision module; Step S4: The control decision module receives the voltage signal V. O1 V O2 The signals are digitally filtered and then compared to determine the system's operating state based on state machine logic. When there is no current in the crane track, the state machine operates in a waiting state, and the control decision module does not output control signals; When the overhead crane track is energized, V O1 When the sampled value is greater than the given start value, the state machine operates in the running state, and the control decision module outputs a fault-free signal to the execution and alarm module. When the overhead crane track is energized, at V O1 The sampled value is greater than the given start value and V O1 and V O2 The absolute value of the difference is less than 0.1 times V. O1 When sampling values, the state machine operates in a fault state, and the control decision module outputs a fault signal to the execution and alarm module; Step S5: When the execution and alarm module receives a fault signal, the control circuit drives the relay to immediately disconnect, cutting off the main power supply of the crane or the critical control circuit to achieve forced power failure protection. At the same time, the drive status indicator light emits an alarm. When the execution and alarm module receives a no-fault signal, the drive status indicator light operates normally.

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