CN201398060Y

CN201398060Y - Electrification over-current protector

Info

Publication number: CN201398060Y
Application number: CN2009200045670U
Authority: CN
Inventors: 吴天际; 王向恒
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-02-16
Filing date: 2009-02-16
Publication date: 2010-02-03
Anticipated expiration: 2019-02-16

Abstract

The utility model relates to an electrification over-current protector, which is composed of a current mutual inductor, a single chip, a bridge-type rectifying diode, a single chip auxiliary power supply circuit and a circuit breaker, and is characterized in that after the circuit is connected, the current mutual inductor, a sampling resistor and the bridge-type rectifying diode are utilized to sample the current in a live wire and to convert the current to a voltage to be inputted into an ADC port of the single chip; when the value which is obtained by accumulating collected data within one seconds through the single chip is more than the setup safety value, the single chip controls the circuit breaker to cut off the electricity supply. By utilizing the electrification over-current protector, the normally-utilized current can be distinguished from the current flowing by the circuit after adopting the large-power electric appliance during the electrification; the single chip can cut off the circuit only under the situation that the large-power electric appliance is connected during the electrification, thus not only ensuring the normal power application of the user, but also effectively preventing the safety potential danger (for example, the large power part is arranged by the side of an inflammable object when the power source is not closed, and after the electrification, theheat which is released by the large power part can ignite the inflammable object to cause the fire) caused for the large power electric appliance is carelessly forgot to close during the power failure.

Description

Overcurrent protective device powers on

Technical field:

The utility model overcurrent protective device that powers on, the zone that is applied in collective's power supply are carried out in the power cuts to limit consumption process prevention work of forgetting to close the event of fire that power supply causes because of personnel's general idea.

Background technology:

China colleges and universities generally carry out the system of cutting off the power supply night in the winter time in term, influence learning life in second day in order to avoid the classmate owing to spending evening and having a rest.And the power consumption equipment (desk lamp, computer etc.) that power cuts to limit consumption every night often makes the classmate forget to close oneself, this comprises that some classmate is because of seeking the convenient high-power electric appliance (immersion heater, electric chafing dish etc.) that uses.Forget that the high-power electric appliance of closing restarts running in the time of can restoring electricity in the morning, thereby cause potential safety hazard such as fire.Shanghai Business School's dormitory breaking out of fire that take place early morning on November 15th, 2008, it is exactly to cause restoring electricity in the morning the back by " immersion heater " initiation fire owing to forget the power supply of pulling out " immersion heater " night that 4 schoolgirls commit suicide by jumping out of the building, and this type of is far above this example by high-power electric appliance in the phenomenon of the back initiation fire that restores electricity.Traditional circuit brake can not move under the situation of high-power electric appliance operate as normal, also can't carry out different responses to the state of circuit constantly in difference, does not still have the protective device at above-described potential safety hazard.

Summary of the invention

For satisfying the demand of above power supply safety; the over-current protection device that powers on that the utility model provides can detect by the electric current to circuit in the certain hour that restores electricity; if detect the electric current that flows through in the circuit greater than set point; then cut off circuit; and other constantly; this circuit brake is in resting state, does not influence high power device in other operate as normal constantly.

The overcurrent protective device (Fig. 2) that powers on is made up of current transformer (1), single-chip microcomputer (2), bridge rectifier diode (3), single-chip microcomputer auxiliary power circuit (4) circuit breaker (5); Be characterized as, at first after circuit restores electricity, by the alternating current on current transformer (1) the collection live wire, be converted into alternating voltage input bridge rectifier diode circuit (3) with sampling resistor, is direct voltage input single-chip microcomputer (2) by bridge rectifier diode with ac voltage rectifier, single-chip microcomputer (2) square adds up to the image data in the continuous 1s, if detected value is greater than the safety value of setting, then cut off the electricity supply by Single-chip Controlling circuit breaker (5), if detected value does not surpass set point, then single-chip microcomputer enters resting state automatically; This single-chip microcomputer (2) is characterized in that being built-in with 8 pin single-chip microcomputers of AD converter and holder; Auxiliary power circuit (4) is characterized in that capacitance decompression, voltage-stabiliser tube voltage stabilizing are to single-chip microcomputer load voltage value 5V.

Description of drawings

Fig. 1 is the technical characterictic figure of overcurrent protective device of originally powering on

Fig. 2 is originally power on overcurrent protective device composition and connection features schematic diagram

Fig. 3 is that wherein A represents current transformer according to the enforcement schematic diagram of Fig. 1 and Fig. 2 design, and B represents the bridge diode rectification circuit, and C represents electric capacity, D represents voltage stabilizing didoe, and E represents diode, and F represents electric capacity, and G represents diode, H represents triode, and I represents sampling resistor, and M represents single-chip microcomputer

Embodiment

The embodiment of the overcurrent protective device that powers on is described below in conjunction with Fig. 3.

The overcurrent protector only works during service restoration after power failure, does not work under the normal situation of circuit supply.

When power supply has just recovered, give single-chip microcomputer (M) power supply through the direct current regulation circuit that electric capacity (C), voltage stabilizing didoe (D), diode (E) and electric capacity (F) are formed, single-chip microcomputer (M) resets and begins operate as normal.At this moment, forget the high-power electric appliance of turning off because of power failure and can behind service restoration, start working that this can make has lasting big electric current to flow through in power supply several seconds of just having recovered in the circuit.

Electric current in the live wire induces electric current in the coil of the current transformer (A) of 10A-10mA, sampling resistor (I) two ends produce and live wire in the alternating voltage that is directly proportional of electric current.Alternating voltage process bridge full-wave rectifier (B), output dc voltage signal, the ADC of access single-chip microcomputer.Normal impulse current when the time of second-time far surpasses the electrical equipment start usually, so impulse current can influence the accuracy of measurement hardly.

The ADC of single-chip microcomputer is the continuous collecting data at work, and by single-chip microcomputer the image data in the continuous 1s square are added up, and its result is proportional to the average power of the circuit in the 1s.In case average power is greater than predefined safety value, under the control of single-chip microcomputer, triode (H) conducting, the trip coil action triggers circuit breaker and cuts off the electricity supply.If during this period of time, the measured value of the power of circuit does not surpass set point, and then single-chip microcomputer (M) quits work, and changes resting state over to.So far, the overcurrent protective device that powers on has just been finished the process of the overcurrent protection that powers on, and changes resting state over to.

Claims

1. overcurrent protective device that powers on, it is made up of current transformer (1), single-chip microcomputer (2), bridge rectifier diode (3), single-chip microcomputer auxiliary power circuit (4) circuit breaker (5); It is characterized by, at first after circuit restores electricity, by the alternating current on current transformer (1) the collection live wire, be converted into alternating voltage input bridge rectifier diode circuit (3) with sampling resistor, is direct voltage input single-chip microcomputer (2) by the bridge rectifier diode circuit with ac voltage rectifier, single-chip microcomputer (2) square adds up to the image data in the continuous 1s, if detected value is greater than the safety value of setting, then cut off the electricity supply by Single-chip Controlling circuit breaker (5), if effective value does not surpass set point, then single-chip microcomputer enters resting state automatically.

2. the overcurrent protective device that powers on according to claim 1 is characterized in that described single-chip microcomputer (2) is the 8 pin single-chip microcomputers that are built-in with A/D converter and holder.

3. the overcurrent protective device that powers on according to claim 1 is characterized in that auxiliary power circuit (4) is that capacitance decompression, voltage-stabiliser tube voltage stabilizing are to single-chip microcomputer rated voltage 5V.