CN2595040Y

CN2595040Y - Digital electronic protector of motor

Info

Publication number: CN2595040Y
Application number: CN 02289131
Authority: CN
Inventors: 韩君杰; 武卫东
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-12-04
Filing date: 2002-12-04
Publication date: 2003-12-24
Anticipated expiration: 2012-12-04

Abstract

The utility model relates to a digital electronic protector of a motor, which belongs to the technical field of relay protection; the utility model is used for overcoming the defect of the existing protector so as to provide the intelligent digital electronic protector. The utility model has the technical proposal that the protector comprises a power circuit, an electric current sampling circuit and a control circuit, wherein, the electric current sampling circuit is composed of three branch circuits with the same structure, each branch circuit is composed of a current mutual inductor and a rectification filter circuit, the control circuit uses a single chip computer as a core part, the reference current and the correlation parameter of the motor are matched and set by a keyboard circuit and a program, and the single chip computer according to an input signal and a setting basic reference is respectively output the correlative signal to a buzzer SP, a state indication circuit, a digital display circuit or a relay control circuit to control or display an alarm. The utility model uses the single chip computer and the switch type power, increases the control precision, observably enhances the anti-jamming capability, and has the advantages of low cost and easy installation.

Description

Motor digital and electronic protector

Affiliated field

The utility model relates to a kind of improved motor protecting device, belongs to technical field of relay protection.

Technical background

Existing motor protecting device is divided into based on the relaying protection formula of relay and analog electrical minor two series products.This two series products respectively has its pluses and minuses; the relaying protection co-volume is big, Heavy Weight; and its performance is subject to the influence of ambient temperature, and the accessory of relay (for example thermal relay, overcurrent relay, overvoltage relay etc.) is easily aging, and country has listed it in superseded row now.The volume of analog electronic protector is much smaller than the relaying protection formula, but it exist control precision not high, react insensitive defective.In recent ten years, the digital technology develop rapidly, various digital electronic components and parts arise at the historic moment, and this makes digital technology become possibility in the application in various fields.

Summary of the invention

Technical problem to be solved in the utility model is to overcome the deficiency of above-mentioned protector and a kind of Intelligent Digital electronic protector that is used for motor is provided.

Problem of the present utility model realizes with following technical scheme:

A kind of motor digital and electronic formula protector, it comprises power circuit, current sampling circuit 1 and control circuit 2, the constituting of each circuit:

A. current sampling circuit 1

It is divided into three branch circuits that structure is identical, each branch circuit is formed by current transformer L1, rectifier diode D1 and filter capacitor C1, resistance R 1, described current transformer L1, rectifier diode D1 and filter capacitor C1, resistance R 1 are connected into half-wave rectifying circuit, filter capacitor C1 is attempted by the two ends of resistance R 1, be attempted by the two ends of resistance R 1 after resistance R 2, the R3 serial connection, the signal input part of the serial connection point connection control circuit 2 of resistance R 2, R3.

B. control circuit 2

Control circuit 2 is a core component with the single-chip microcomputer, adopt the 87LPC767 chip, the signal input part AD0 of analog-to-digital conversion part among the signal output part order sheet machine chip IC1 of three current sampling circuits 1, AD1, AD2, resistance R 10, R11, R12 and three button AN1, AN2, AN3 constitutes keyboard circuit 3, promptly an end of three buttons meets the P0.0 of single-chip microcomputer respectively, P0.1, the P0.2 mouth, other end ground connection, three lift resistance R 10, R11, the end of R12 and button AN3, AN2, the end of AN1 joins, another termination power VCC, memory IC 3 adopts serial EEPROM chip, its SCL, the SDA pin connects SCL and the SDA port of IC1 respectively; Resistance R 13 and relay J have constituted relay and control circuit 7, control coil serial connection back one end of resistance R 13 and relay J and the P1.5 mouth of IC1 join, other end ground connection, the normally closed contact of relay then is serially connected in the control loop of the button AN4 composition of controlling A.C. contactor CJO, and the main normally opened contact of A.C. contactor CJO connects the binding post of motor.

Above-mentioned motor digital and electronic protector, described control circuit 2 is set up intelligent temperature sensor S, and the signal output part of intelligent temperature sensor S connects the P0.7 mouth of single-chip microcomputer.

Above-mentioned motor digital and electronic protector, described control circuit 2 is set up operating state indicating circuit 5, warning circuit 4 and digital display circuit 6, described operating state indicating circuit 5 adopts light-emitting diode D8, D9, be connected to P1.6 and the P1.7 mouth of IC1 after light-emitting diode and its current-limiting resistance serial connection, other end ground connection; Described warning circuit 4 adopts buzzer SP, the P0.6 mouth of the termination IC1 of buzzer SP, and other end ground connection, described digital display circuit 6 adopts digital display chip IC2, and the SCL of IC2, SDA pin connect SCL and the SDA port of IC1 respectively.

Above-mentioned motor digital and electronic protector; described power circuit is by three-terminal voltage-stabilizing chip IC 4; high frequency transformer T; capacitor C 4; C5; C6; C7; resistance R 16; inductance L; clamp diode D4; diode D5; D6; D7 forms; wherein; one end of the elementary winding of an input termination high frequency transformer of power supply; the same inscription end of elementary winding and the D of IC4 end join; be connected on the two ends of the elementary winding of high frequency transformer after clamp diode D4 and the diode D5 serial connection; high frequency transformer is provided with two secondary winding; one of them constitutes output loop; another constitutes feedback loop; the secondary winding and the diode D6 that constitute output loop are connected into halfwave rectifier; the negative pole of diode D6 and inductance L; capacitor C 6; the filter circuit that C7 forms joins; constitute the same inscription end serial connection diode D7 of the secondary winding of feedback loop; connect the C end of IC4 after the resistance R 16; capacitor C 5 is its filter capacitor; the S end ground connection of IC4, capacitor C 4 is the filter capacitor of mains side.

According to the motor protector that the utility model is made, state of motor is that the operating current with the current transformer collection is to convert in the basis.Sampled value is given single-chip microcomputer after becoming voltage signal behind rectifying and wave-filtering, be converted into digital quantity by single-chip microcomputer.Adopt single-chip microcomputer as the control core, and adopt switching mode voltage stabilizer, so control precision improves greatly, and antijamming capability significantly strengthens.The utlity model has cost advantage low, easy for installation, and its scope of application is extensive, up to large-size machine, can realizes easily as long as change the current transformation ratio of current transformer from middle and small motor.

Description of drawings

Fig. 1 is an electric theory diagram of the present utility model;

Fig. 2 is the electrical schematic diagram of the used power supply of control circuit;

Fig. 3 is an electrical schematic diagram;

Fig. 4 is the Single Chip Microcomputer (SCM) program control flow chart.

Embodiment

Invention basic point of the present utility model is Digital Electronic Technique is applied to motor protection.This protector is sampled to the operating current of motor by current transformer; behind the current rectifying and wave filtering circuit of sampled value through diode and capacitor composition; carry out dividing potential drop through resistance R 2, R3 again; be transformed to suitable voltage and give single-chip microcomputer IC1; single-chip microcomputer carries out analog-to-digital conversion with signal, thereby the operating current of motor is become digital quantity by analog quantity.Single-chip microcomputer compares this digital quantity and set point; can judge thus whether motor is in overcurrent or three-phase imbalance state; if; buzzer SP reports to the police; after the time-delay of setting, still be in this state if detect motor, single-chip microcomputer will turn-off A.C. contactor CJO by auxiliary relay J; with the dump of motor, thereby reach the purpose of protecting motor.To open phase fault, then can not set this time-delay, but disconnect immediately.

The input signal of control circuit 2 has two groups, and one group is current signal, and one group is the temperature signal that temperature sensor S gathers.Temperature sensor S adopts intelligent, is the transducer of DS1820 such as model, and what its was exported is digital signal.Temperature sensor S is attached at the iron core place of motor, thereby collects the temperature parameter at iron core place.Resistance R 10, R11, R12 and three button AN1, AN2, AN3 constitute keyboard circuit 3, and it cooperates rated current, temperature that is used for setting motor and the time that the overcurrent time-delay closing is set with the keyboard service routine.Like this, single-chip microcomputer will and be provided with the contrast of benchmark according to input signal, export control signal respectively and give buzzer SP, electric machine operation state indicating circuit 5, digital display circuit 6 or relay relay and control circuit 7, control or show, reports to the police.

The RXD of singlechip chip, TXD can also connect outside serial communication circuit, provide the running parameter of this TV station motor with this to the centralized monitor center, with centralized monitor.

Fig. 3 is a program flow diagram of the present utility model.After reset circuit resetted single-chip microcomputer, program just began to carry out from " " frame of program flow diagram, and program is carried out initialization earlier, according to the delay time of content setting load current value, temperature value and the action of storing among the memory EEPROM.After this, program just begins each operational factor of circulatory monitoring motor, and each parameter is shown, when parameter occurs when unusual, Program time delay started auxiliary relay and provides control signal after a period of time.Memory adopts serial storage able to programme, erasable, and as AT24C02, the storage data of sort memory are difficult for losing.

The operating current and the working temperature of motor are all shown by display in real time; The normal operating conditions of motor and overcurrent, the phase failure, electric leakage, temperature are crossed high malfunction, show (two diodes of the D8 that only drawn among Fig. 3, D9, the state number of Xian Shiing can increase the number of diode as required) respectively by light-emitting diode.

The power supply that the utility model is supplied with each chip and control circuit 2 adopts switching type power supply, and it converts a direct voltage direct voltage of low pressure to once more through switching circuit, and its switch chip adopts TOP210.

Claims

1. motor digital and electronic formula protector, it comprises power circuit, current sampling circuit [1] and control circuit [2], it is characterized in that the constituting of each circuit:

B. current sampling circuit [1]

It is divided into three branch circuits that structure is identical, each branch circuit is formed by current transformer L1, rectifier diode D1 and filter capacitor C1, resistance R 1, described current transformer L1, rectifier diode D1 and filter capacitor C1, resistance R 1 are connected into half-wave rectifying circuit, filter capacitor C1 is attempted by the two ends of resistance R 1, be attempted by the two ends of resistance R 1 after resistance R 2, the R3 serial connection, the signal input part of the serial connection point connection control circuit [2] of resistance R 2, R3.

B. control circuit [2]

Control circuit [2] is a core component with single-chip microcomputer IC1, adopt the 87LPC767 chip, the signal input part AD0 of analog-to-digital conversion part among the signal output part order sheet machine chip IC1 of three current sampling circuits [1], AD1, AD2, resistance R 10, R11, R12 and three button AN1, AN2, AN3 constitutes keyboard circuit [3], promptly an end of three buttons meets the P0.0 of single-chip microcomputer respectively, P0.1, the P0.2 mouth, other end ground connection, three lift resistance R 10, R11, the end of R12 and button AN3, AN2, the end of AN1 joins, another termination power VCC, memory IC 3 adopts serial EEPROM chip, its SCL, the SDA pin connects SCL and the SDA port of IC1 respectively; Resistance R 13 and relay J have constituted relay and control circuit 7, control coil serial connection back one end of resistance R 13 and relay J and the P1.5 mouth of IC1 join, other end ground connection, the normally closed contact of relay then is serially connected in the control loop of the button AN4 composition of controlling A.C. contactor CJO, and the main normally opened contact of A.C. contactor CJO connects the binding post of motor.

2. motor digital and electronic protector according to claim 1 is characterized in that described control circuit [2] is set up intelligent temperature sensor S, and the signal output part of intelligent temperature sensor S connects the P0.7 mouth of single-chip microcomputer IC1.

3. motor digital and electronic protector according to claim 2, it is characterized in that, described control circuit [2] is set up operating state indicating circuit [5], warning circuit [4] and display circuit [6], described operating state indicating circuit [5] adopts light-emitting diode D8, D9, be connected to P1.6 and the P1.7 mouth of IC1 after light-emitting diode and its current-limiting resistance serial connection, other end ground connection; Described warning circuit [4] adopts buzzer SP, the P0.6 mouth of the termination IC1 of buzzer SP, and other end ground connection, described display circuit [6] adopts digital display chip IC2, and the SCL of IC2, SDA pin connect SCL and the SDA port of IC1 respectively.

4. motor digital and electronic protector according to claim 3; it is characterized in that; described power circuit is by switch chip IC4; high frequency transformer T; capacitor C 4; C5; C6; C7; resistance R 16; inductance L; clamp diode D4; diode D5; D6; D7 forms; wherein; one end of the elementary winding of an input termination high frequency transformer of power supply; the same inscription end of elementary winding and the D of IC4 end join; be connected on the two ends of the elementary winding of high frequency transformer after clamp diode D4 and the diode D5 serial connection; high frequency transformer is provided with two secondary winding; one of them constitutes output loop; another constitutes feedback loop; the secondary winding and the diode D6 that constitute output loop are connected into halfwave rectifier; the negative pole of diode D6 and inductance L; capacitor C 6; the filter circuit that C7 forms joins; constitute the same inscription end serial connection diode D7 of the secondary winding of feedback loop; connect the C end of IC4 after the resistance R 16; capacitor C 5 is its filter capacitor; the S end ground connection of IC4, capacitor C 4 is the filter capacitor of mains side.