Anti-electric shock safe power utilization system on construction site

Abstract

The invention discloses a construction site anti-electric shock safe power utilization system, which comprises a main controller, the main controller is in communication connection with a display unit through Ethernet / RS485, the main controller is connected with a plurality of microcontroller systems through RS485 / Ethernet, each microcontroller system is in communication connection with a circuit identification system through RS485 / CAN, and the circuit identification system is connected with the display unit through RS485 / Ethernet. And each group of the microcontroller system and the circuit identification system which are in communication connection through RS485 / CAN are arranged in the same explosion-proof box. Compared with a leakage current monitoring scheme, the explosion-proof anti-electric shock device adopts a method of combining power supply physical isolation, insulation monitoring and fault positioning, is more reliable, protects field personnel from electric shock, guarantees the field construction safety of the personnel, reduces the field fire risk, has an explosion-proof function for single-phase insulation or grounding faults, and has a good application prospect. The normal operation of equipment is not influenced; according to the invention, a neutral point grounding system is redesigned to be a neutral point non-grounding system, the fault position can be positioned when the load is in single-phase insulation or fault, and cutting and alarming can be carried out.

Description

Technical Field

[0001] The invention belongs to the technical field of safe electricity use of equipment at a construction site, and in particular relates to a safe electricity use system for preventing electric shock at a construction site. Background Art

[0002] There are many types of equipment that need to be powered in the oil field, and the on-site environment is complex. Electrical equipment is easily affected by moisture, aging or insulation damage. Once the electrical system has insulation damage or leakage, it will not only ignite the flammable gas in the oil field, causing fire or explosion accidents, but also may cause electric shock to people, resulting in casualties. Therefore, facing the harsh natural environment, the leakage protection work of oilfield engineering electrical equipment is very important. In practice, the leakage protection work of oilfield equipment still has the problem of insufficient standardization of leakage protection circuit design, which brings hidden dangers to the safe operation of electrical equipment. The existing technology mostly adopts zero-sequence current or leakage current protection schemes, which have deficiencies and some defects in the safety circuit, and leakage is prone to cause casualties.

[0003] Therefore, it is very important to provide a safe and reliable power supply for on-site equipment and ensure the safety of on-site personnel. Summary of the invention

[0004] The purpose of the present invention is to provide a construction site anti-electric shock safety electricity system, which solves the problem of leakage in the detection process in the prior art that causes casualties.

[0005] The technical solution adopted by the present invention is: a safe electricity use system for preventing electric shock at a construction site, including a main controller, the main controller is connected to a display unit via Ethernet / RS485 communication, the main controller is connected to several microcontroller systems via RS485 / Ethernet, each microcontroller system is connected to a circuit identification system via RS485 / CAN communication, and each group of microcontroller systems and circuit identification systems connected via RS485 / CAN communication are installed together in the same explosion-proof box.

[0006] The present invention is also characterized in that:

[0007] The circuit identification system includes an insulation detection board and an insulation fault location board, the insulation fault location board is connected to a plurality of zero-sequence current transformers through wires, the insulation detection board is provided with a first analog input and output module, and the first analog input and output module is respectively connected to a voltage sampler, a current sampler and an insulation sampler through wires;

[0008] It also includes a safety transformer, and the input ends of the voltage sampler, the current sampler and the insulation sampler are respectively connected to the output end of the safety transformer.

[0009] The microcontroller system is provided with a digital input and output module and a second analog input and output module, the digital input and output module is respectively connected with an indicator light, a buzzer, a contactor and a reset button through wires, and the second analog input and output module is respectively connected with a temperature sensor through wires;

[0010] The safety transformer is connected to an indicator light via electrical wires;

[0011] The indicator lights and buzzers are explosion-proof, and the indicator lights and buzzers are connected to operating handles respectively;

[0012] A heat dissipation module is arranged outside the explosion-proof box.

[0013] The beneficial effects of the present invention are:

[0014] 1. The intelligent explosion-proof and electric shock-proof device uses a combination of power supply physical isolation, insulation monitoring and fault location. It is more reliable than the leakage current monitoring solution. Once the voltage of the human body in contact with the equipment reaches the safe voltage value that can be tolerated, the device will start the automatic protection function, and the on-site equipment can still operate normally. The device can monitor all live equipment on site in an all-round way, and can accurately monitor and troubleshoot the source of the fault, protect on-site personnel from electric shock, ensure the safety of on-site construction personnel, reduce the risk of on-site fire, and play an explosion-proof function in the event of single-phase insulation or grounding faults, without affecting the normal operation of the equipment;

[0015] 2. The present invention redesigns the neutral point grounding system into a neutral point ungrounded system, and can locate the fault position, cut off and alarm when the load is single-phase insulated or faulty. The core of this on-site anti-electric shock safety power system is to establish a microcontroller system with unified architecture and data, which can effectively connect various data modules, integrate the power information resources of various lines in on-site operations, break the single function of each component, form multi-scenario information linkage, realize the information integration of the on-site power system, and centrally store and intelligently analyze various normalized and non-normalized power data, comprehensively promoting the on-site power safety management and control to panoramic data management, transparent operation status, intelligent diagnosis and decision-making, and efficient equipment repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the explosion-proof box structure in the construction site anti-electric shock safety power system of the present invention;

[0017] Figure 2 It is a schematic diagram of the internal connection structure of the construction site anti-electric shock safety power system of the present invention;

[0018] Figure 3 It is a schematic diagram of the parallel use and management of multiple construction site anti-electric shock safety electricity systems according to the present invention. DETAILED DESCRIPTION

[0019] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] The construction site anti-electric shock safety electricity system includes an explosion-proof box, which is equipped with a circuit identification system, a microcontroller system and a display unit. The circuit identification system is connected to the microcontroller system via RS485 / CAN communication, the microcontroller system is connected to the main controller via RS485 / Ethernet, and the main controller is connected to the display unit via Ethernet / RS485 communication. When working, the circuit identification system collects current, voltage, insulation status and other signals, and transmits them to the microcontroller via RS485 / CAN communication. The microcontroller processes the data and transmits it to the display unit via the main controller. The display unit can intuitively monitor and identify the on-site working conditions of the circuit device, which is convenient for on-site control;

[0021] It is worth noting that: Figure 3 As shown, the intelligent explosion-proof and electric shock-proof device for electrical places can be used alone or in parallel. It can be managed uniformly by a main controller, and human-computer interaction is performed through the display unit. The main controller receives data from each microcontroller through communication. The main controller and the display unit can be installed in a safe area.

[0022] Specifically, Figure 2 As shown, the circuit identification system includes an insulation detection board and an insulation fault locating board. The insulation fault locating board is connected to a plurality of zero-sequence current transformers through wires. The insulation fault locating board includes 4, 8, and 12 channel models, and each channel can be connected to 3 zero-sequence current transformers. The insulation detection board is provided with a first analog input and output module, and the first analog input and output module is respectively connected to a voltage sampler, a current sampler, and an insulation detector through wires. It also includes a safety transformer, and the input ends of the voltage sampler, the current sampler, and the insulation detector are respectively connected to the output end of the safety transformer. The insulation monitoring board has current and phase-to-phase short-circuit protection functions, such as Figure 2 As shown, a current transformer and a temperature sensor are also provided between the safety transformer and the connecting wires of the voltage sampler, the current sampler and the insulation tester. The voltage sampler, the current sampler and the insulation tester collect signals through the safety transformer, specifically: the total load voltage is sampled by the voltage sampler, the total load current is sampled by the current, the insulation state of the load circuit detection unit is detected, and then transmitted to the insulation detection board, and then transmitted to the microcontroller for processing.

[0023] The safety transformer is connected to an indicator light through electric wires to display the working status of the safety transformer. The indicator light is set with a safety limit value. If the on-site personnel are busy with work and ignore the indicator light, the device will play an automatic protection function.

[0024] The microcontroller is provided with a digital input and output module and a second analog input and output module. The digital input and output modules are connected to indicator lights, buzzers, contactors and reset buttons through wires. The second analog input and output modules are connected to temperature sensors through wires to sample the temperature in the explosion-proof box. The microcontroller processes the signals transmitted through the insulation detection board and the insulation fault location board to monitor the current changes of the entire load. For serious load overload, for installation protection, on the one hand, a buzzer is used to prompt, and on the other hand, it can also be displayed through the display unit, which is convenient for manual safe operation and control. As an information terminal, the microcontroller system has the advantages of accurate signal acquisition and conversion, strong anti-interference ability, and can calibrate the accuracy of analog and digital output signals. It can efficiently integrate all information of other functional modules, accurately judge and analyze the signal information of each circuit, and store and remember the collected information. When it is judged that the heat of a certain circuit reaches the safety critical value, it will automatically process it, so that the circuit is powered off, and automatic protection is achieved, and other circuits are working normally; after the microprocessor collects the signal, it is processed by program algorithm calculation and transmits the information to the alarm display terminal, accurately and quickly reflecting the status of each circuit.

[0025] Among them, the insulation monitoring board, insulation fault location board, display unit, and microcontroller all support AC / DC24V power supply, and can use a transformer to step down the voltage to AC24V through the main circuit or use a switch to control the power supply.

[0026] The contactor should contain load contacts, including at least one normally open contact, connected to the microcontroller to indicate the contactor status.

[0027] The indicator lights and buzzers are both explosion-proof and can better adapt to the construction site environment. The indicator lights and buzzers are respectively connected to operating handles to enhance the sensitivity of intelligent signal response and improve intelligent technical support, providing users with safer, smarter and more convenient operation.

[0028] A heat dissipation module is arranged outside the explosion-proof box to improve the safety technical level of the overall anti-electric shock and explosion-proof device.

[0029] The overall technical solution of this system is: the design concept of dual combination function of acquisition system plus hardware, sending instructions to each component through the system, monitoring the operation of each component and the control of the working system, realizing the power supply working condition of each component control line and the real-time working feedback value of the system monitoring circuit, achieving dual protection technical functions, improving the sensitivity of the monitoring system, avoiding the limitations of single protection, modularizing functions, faster operation feedback speed, and improving safety assurance speed. At the same time, it has reserved upgrade functions, open design, and strong compatibility.

[0030] The main circuit of this system adopts the technology of local ungrounded neutral point (IT power supply). Because the neutral point of its power supply is not grounded, when a relative ground insulation fault occurs at the load end, it cannot form a circuit to the ground, and only a very small capacitive leakage current will be generated, which will not cause harm to the human body. Before the circuit breaker is actuated, the system makes a defensive feedback to ensure the connectivity of the equipment power supply. The construction site anti-electric shock safety power system is a safe power protection device for well site operations. It can be connected to 380VAC and connected in series to the rear stage of the main switch. For accidental electric shock to the human body caused by line aging, wear, extrusion, etc., and line overlap caused by rain, humidity, and immersion, predictive maintenance can be achieved to protect the safety of on-site personnel and equipment. In addition to anti-electric shock, leakage monitoring, distributed capacitance, load voltage, current, power and other monitoring, the explosion-proof device also has voltage and current protection functions.

[0031] The addition of a physical harmonic shielding layer design to the system can simultaneously monitor and warn of multiple parameters of the load power supply line in real time, analyze and determine, for example, the insulation status, and issue fault alarms and conduct linkage evaluations on other equipment for selective protection; through discrete current capture technology, the electric field (reverse magnetic field) function is immediately activated for the collected current and electrons, and the discrete current and electrons are absorbed back into the electric field to prevent leakage accidents.

[0032] Example 1

[0033] Working process: The insulation detection board samples the total load current through the current sampler, samples the total load voltage through the voltage sampler, monitors the insulation status of the load line through the insulation detector, samples the temperature value of the safety transformer through the temperature sensor, and then transmits it to the insulation detection board, and then to the microcontroller; the insulation fault location board samples the load status through the zero-sequence current transformer and transmits it to the microcontroller through communication;

[0034] The microcontroller samples the button status through the digital input and output module, controls the contactor coil and buzzer through the digital input and output module, and samples the temperature of the temperature sensor in the cabinet through the second analog input module. The microcontroller transmits the data to the display unit through the main controller for display. The operator can view, record, compare, and modify the information through the display unit.

[0035] Example 2

[0036] The construction site anti-electric shock safety electricity use system includes an explosion-proof box, which is equipped with a circuit identification system, a microcontroller and a display unit. The circuit identification system is connected to the microcontroller via RS485 / CAN communication, the microcontroller is connected to the main controller via RS485 / Ethernet, and the main controller is connected to the display unit via Ethernet / RS485 communication. When working, the circuit identification system collects current, voltage, insulation status and other signals, and transmits them to the microcontroller via RS485 / CAN communication. The microcontroller processes the data and transmits it to the display unit via the main controller. The display unit can intuitively monitor and identify the on-site working conditions of the circuit device, which is convenient for on-site control. The intelligent explosion-proof and anti-electric shock device in the power consumption site is used separately, managed by the main controller, and human-computer interaction is performed through the display unit. The main controller receives data from each microcontroller through communication.

[0037] Example 3

[0038] On the basis of Example 2, the circuit identification system specifically includes an insulation detection board and an insulation fault locating board. The insulation fault locating board is connected to a number of zero-sequence current transformers through wires, wherein the insulation fault locating board includes a 4-channel model, each channel can be connected to 3 zero-sequence current transformers, the insulation detection board is provided with a first analog input and output module, the first analog input and output module is respectively connected to a voltage sampler, a current sampler and an insulation detector through wires, and also includes a safety transformer, the input ends of the voltage sampler, the current sampler and the insulation detector are respectively connected to the output end of the safety transformer, the insulation monitoring board has current and phase-to-phase short-circuit protection functions, and a current transformer and a temperature sensor are also provided between the safety transformer and the voltage sampler, the current sampler and the insulation detector connecting wires. The voltage sampler, the current sampler and the insulation detector collect signals through the safety transformer, specifically: the total load voltage is sampled by the voltage sampler, the total load current is sampled by the current, the insulation state of the load circuit detection unit is detected, and then transmitted to the insulation detection board, and then transmitted to the microcontroller for processing.

Claims

1. The construction site anti-electric shock safety power system is characterized by: The invention comprises a main controller, wherein the main controller is connected to a display unit via Ethernet / RS485 communication, the main controller is connected to a plurality of microcontroller systems via RS485 / Ethernet, each of the microcontroller systems is connected to a circuit identification system via RS485 / CAN communication, and each group of microcontroller systems and circuit identification systems connected via RS485 / CAN communication are installed together in the same explosion-proof box.

2. The construction site anti-electric shock safety electricity system according to claim 1 is characterized in that: The circuit identification system comprises an insulation detection board and an insulation fault locating board, wherein the insulation fault locating board is connected to a plurality of zero-sequence current transformers through wires, and the insulation detection board is provided with a first analog input and output module, wherein the first analog input and output module is respectively connected to a voltage sampler, a current sampler and an insulation sampler through wires; It also includes a safety transformer, and the input ends of the voltage sampler, the current sampler and the insulation sampler are respectively connected to the output end of the safety transformer.

3. The construction site anti-electric shock safety electricity system according to claim 1 is characterized in that: The microcontroller system is provided with a digital input and output module and a second analog input and output module. The digital input and output module is respectively connected to an indicator light, a buzzer, a contactor and a reset button through wires, and the second analog input and output module is respectively connected to a temperature sensor through wires.

4. The construction site anti-electric shock safety electricity system according to claim 2 is characterized in that: The safety transformer is connected with an indicator light via electric wires.

5. The construction site anti-electric shock safety electricity system according to claim 4 is characterized in that: The indicator light and buzzer are both explosion-proof and are respectively connected with an operating handle.

6. The construction site anti-electric shock safety electricity system according to claim 1 is characterized in that: A heat dissipation module is arranged outside the explosion-proof box.

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