Intelligent prevention and control method for electrical fire
Technical Field
The invention can be widely applied to the technical fields of fire fighting, electric power, electromechanics and the like in activities such as life, production, management and the like of people, and particularly relates to an intelligent electric fire prevention and control method.
Background
The protector for protecting the overload, short circuit, electric leakage, residual current and the like of the whole loop used by the existing circuit is a technical protection measure aiming at protecting the circuit and personal safety, and the protection of the short circuit, the overcurrent, the electric leakage and the residual current can be triggered to trip out the protection circuit or the personal safety only when the protector occurs, namely the protector has a protection effect on the faults of the overload, the short circuit, the electric leakage and the residual current of the whole loop, and the protector is a target which is already determined by the research and development of electrical engineers. However, a large number of experiments prove that an ignition source capable of causing a fire disaster is generated when the protectors jump off, and if the fault point combustion conditions are met, the fire disaster is inevitable. Therefore, the ignition source generated by short circuit, overcurrent, electric leakage and residual current electrical fault is not controlled. A large number of experiments also prove that the protectors have no protective effect on interphase high-impedance discharge, single/double-phase carbonization conduction discharge, full-line overload, short circuit, poor contact discharge and under-overvoltage electrical faults which can generate a fire ignition source in a circuit.
In fact, the working principle of the existing short-circuit, overcurrent, electric leakage and residual current protectors can also explain the reason that the fire ignition source caused by the short-circuit, overcurrent, electric leakage and residual current faults cannot be eliminated. The short circuit, overcurrent, leakage current and residual current circuit breakers used in the existing circuit can convert the changed electromagnetic field, the heated hot metal sheet, the induced current difference and the three-phase current difference into energy for pulling an armature to move or the hot metal sheet to expand or pull a coil when the protected circuit generates current with extremely high change rate, long-time overcurrent, leakage current and three-phase unbalanced residual current, so as to drive the moving contact to separate to break the circuit, thereby avoiding the fault of the fault circuit from further influencing the main circuit. Because the faults of poor contact discharge, interphase high-impedance discharge, single/double-phase carbonization discharge and single/double-phase carbonization conduction discharge can not generate current with extremely high change rate, long-time overcurrent, leakage current and three-phase unbalanced residual current, the existing four circuit protection circuit breakers can not implement protection.
Therefore, no control measure aiming at generating an ignition source for electrical faults exists in China, the control measure is the important reason that electrical fires are frequent in China, and fire statistics data show that the electrical fires are the top of all kinds of fires for decades. Especially, the electrical fire in the last 20 years in China accounts for more than 30% of the majority of the years, and the situation of the electrical fire is very severe.
Disclosure of Invention
The purpose of the invention is as follows: the method for effectively preventing and controlling the fire ignition source generated by interphase high-impedance discharge, single/double-phase carbonization path conduction, full-loop overload, short-circuit discharge, leakage discharge, poor-contact discharge and under-overvoltage discharge faults is provided.
Therefore, the invention provides the intelligent prevention and control method for the electrical fire, which comprises the following steps:
step 1: and acquiring current, voltage, resistance and power factor data through a large number of normal power consumption discharge and fault discharge experiments, and establishing a normal power consumption discharge and fault discharge characteristic database.
Step 2: and the combined current sensor and the like are used for acquiring the electric performance technical parameters such as current, voltage, resistance, power factor and the like of the protected circuit in real time.
And step 3: and (3) calculating and processing the data acquired in real time in the step (2) by using a single chip microcomputer, comparing the data with the normal power consumption discharge and fault discharge characteristic data in the database in the step (1), identifying and judging whether the circuit is in normal discharge or fault discharge, and further judging the fault discharge type and fault intensity if the circuit is in fault discharge.
And 4, step 4: judging whether the energy of the electrical fault discharge reaches the set minimum energy value of combustible materials caused by the type of fault verified by experiments according to the fault discharge type identified in the step 3, if the energy reaches or exceeds the set minimum energy value, sending a signal to a tripping mechanism by the singlechip to trip and cut off the fault discharge in time, and meanwhile pushing the fault signal to a corresponding management platform; if not, the step 5 is carried out.
And 5: judging whether the voltage exceeds a specified threshold range, if the voltage is lower than or exceeds a specified voltage value, sending a signal to a tripping mechanism to trip a cut-off circuit in time, and meanwhile pushing a fault signal to a corresponding management platform; and if the tripping signal is not sent to the tripping mechanism, the tripping signal is not sent to the tripping mechanism.
Further, the characteristic data of the normal power consumption discharge in the step 1 comprises discharge arc characteristic electrical performance data such as plug-in and plug-out plugs on the circuit, silicon controlled switches, electric welding operation, impact drilling operation and the like; the characteristic data of fault discharge comprises characteristic electrical property data of fault discharge such as short-circuit discharge, leakage discharge, interphase high-impedance discharge, poor contact discharge, ground discharge, single/double-phase carbonization path conduction discharge and the like on a circuit.
Further, the characteristic data in the step 2 is acquired, and the electrical property data is acquired by using a current detector and the like and is transmitted to the single chip microcomputer.
Further, the comparison algorithm for identifying the fault discharge in the step 3 is a combination of one or more of contrast, wavelet, fourier and neural networks.
Furthermore, the minimum energy value for researching the fire ignition source set by the type of fault starts from strengthening prevention and control and reducing electrical fire, and is verified by experiments that a large amount of fault discharge releases energy to ignite combustible materials, and the ignited combustible materials are confirmed to be absorbent cotton and filter paper sheets through the discussion of electrical and fire prevention and control experts and fire investigation experts.
Meanwhile, the provided intelligent electric fire prevention and control device (hereinafter referred to as prevention and control device) is connected between a load and a power supply, the single chip microcomputer can also directly give out a signal to control a release, and the prevention and control device controls a fire ignition source of a protected circuit by using the intelligent electric fire prevention and control method.
The invention has the beneficial technical effects that:
the invention can identify, judge and control fire ignition sources generated by faults such as full-loop overload, short-circuit discharge, leakage discharge, poor contact discharge, interphase high-impedance discharge, single/double-phase carbonization path conduction, undervoltage and the like. Can effectively control the ignition source of the electrical fire so as to prevent the electrical fire from happening.
Drawings
FIG. 1 is a flow chart of the steps of the prevention and control method of the present invention.
FIG. 2 is a schematic diagram of the circuit of the prevention and control device of the present invention.
Detailed Description
The invention is described in further detail below with reference to the figures and the detailed description.
The invention judges the type of the electrical fault according to the change of electrical performance parameters such as current, voltage, resistance and the like in a current loop caused when the discharge type electrical fault occurs. And controlling the fire ignition source of the protected circuit by using the prevention and control device.
The circuit principle is shown in fig. 2: the prevention and control device is connected between a load and a power supply, and the fire ignition source of the protected circuit caused by electrical faults is controlled by using the prevention and control technical method. The combined current sensor is used for collecting electrical property data, the single chip microcomputer is used for carrying out data processing, analysis and fault type and fault intensity judgment, and when electrical fault conditions needing to be cut off are found, the single chip microcomputer gives a tripping signal to control the tripper to trip and cut off a circuit power supply.
As shown in fig. 1, the specific judgment and control includes:
step 1: and acquiring current, voltage, resistance and power factor data through a large number of normal power consumption discharge and fault discharge experiments, and establishing a normal power consumption discharge and fault discharge characteristic database.
The characteristic data of normal power consumption discharge comprises discharge arc characteristic electrical performance data, curves and the like of a plug, a silicon controlled switch, electric welding operation, impact drill operation and the like on a circuit; the characteristic data of fault discharge comprises characteristic electrical performance data and curves of faults such as short-circuit discharge, leakage discharge, interphase high-impedance discharge, poor contact discharge, earth discharge, single/double-phase carbonization path conduction discharge and the like on a circuit.
Step 2: and the combined current sensor and the like are used for acquiring the electric performance technical parameters such as current, voltage, resistance, power factor and the like of the protected circuit in real time.
And step 3: and (3) calculating and processing the data acquired in real time in the step (2) by using a single chip microcomputer, comparing the data with the normal power consumption discharge and fault discharge characteristic data in the database in the step (1), identifying and judging whether the circuit is in normal discharge or fault discharge, and further judging the fault discharge type if the circuit is in fault discharge. The specific comparison algorithm is one or more of contrast, wavelet, Fourier and neural network.
And 4, step 4: judging whether the energy of the electrical fault discharge reaches the set minimum energy value of combustible materials caused by the type of fault verified by experiments according to the fault discharge type identified in the step 3, if so, sending a signal to a tripping mechanism by the single chip microcomputer to trip and cut off the fault discharge in time, and meanwhile, pushing the fault signal to a corresponding management platform; if not, the step 5 is carried out.
And 5: judging whether the voltage exceeds a specified threshold range, if the voltage is lower than or exceeds a specified voltage value, sending a signal to a tripping mechanism to trip a cut-off circuit in time, and meanwhile pushing a fault signal to a corresponding management platform; and if the tripping signal is not sent to the tripping mechanism, the tripping signal is not sent to the tripping mechanism.
The set minimum energy value for triggering the fire is obtained from the starting of strengthening prevention and control and reducing electrical fire through experimental verification that a large amount of fault discharge releases energy to ignite combustible materials. And the ignited combustible materials are confirmed to be absorbent cotton and filter paper sheets through the discussion of electrical, fire prevention and control and fire investigation experts.
Experimental conditions and environment: the invention relates to a prevention and control device which is connected in a household 220V circuit, wherein one end of the circuit is connected with a power supply port, the other end of the circuit is connected with a fault module port and a common household electric load or load cabinet port, interphase high-impedance discharge, single-phase carbonization conduction discharge, double-phase carbonization conduction discharge, electric leakage, short circuit and poor contact discharge fault are carried out on the fault module, standard combustible substances are placed at fault points, whether the standard combustible substances are ignited or not is observed when the fault occurs, and if the prevention and control device acts to disconnect the circuit before ignition, the electric fire can be effectively prevented and controlled; otherwise, if the fire is not activated or the combustible is ignited, the electric fire cannot be effectively prevented and controlled. The results of the specific experiments are shown in table 1.
TABLE 1 Fault discharge prevention and control experiment results
Through experiments, the invention can effectively control and prevent electrical fire by more than 60 percent of electrical fire ignition sources with short circuit and double-phase carbonization conduction discharge faults, more than 90 percent of electrical fire ignition sources with poor contact discharge faults, more than 90 percent of electrical fire ignition sources with interphase high-impedance discharge faults, more than 90 percent of electrical fire ignition sources with single-phase carbonization conduction discharge faults and more than 99.9 percent of leakage discharge faults. If the prevention and control device is widely popularized and applied nationwide, 2-4 electric fire prevention and control switches can be used by each family, a large number of production places such as a generation workshop and the like can be used, the using amount is large, and great economic benefits can be generated while a large number of electric fires are reduced.