CN2181660Y

CN2181660Y - Intelligent frequency-change refrigerating unit

Info

Publication number: CN2181660Y
Application number: CN 93235686
Authority: CN
Inventors: 赵泉勇; 李涛; 彭达生; 林成基; 边文志
Original assignee: Pufa Electronic Tech Dev Co Tangshan City
Current assignee: Pufa Electronic Tech Dev Co Tangshan City
Priority date: 1993-12-25
Filing date: 1993-12-25
Publication date: 1994-11-02
Anticipated expiration: 2003-12-25

Abstract

The utility model relates to an intelligent frequency-change refrigerating unit, which belongs to the technical field of automatic temperature control. The main control circuit of the intelligent frequency-change refrigerating unit takes an 8098 single chip computer as a kernel. The control circuit outputs PWM pulse waveforms, and carries out regular switching by a driving circuit which controls a three-phase inversion bridge. Output switching signals form three-phase PWM sinusoidal waves with high efficiency used for driving a nd-fe-b three-phase permanent magnet synchronous motor matching with a frequency-change control circuit and a spiral type compressor. The utility model which applies computer technology to the frequency-change control circuit has the advantages of intellectualization, small size, low noise, low energy consumption, horizontal temperature control and high power factors.

Description

Intelligent frequency-change refrigerating unit

The utility model relates to a kind of intelligent frequency-conversion refrigerating plant, belongs to temperature automatic control technology field.

The prior art refrigerating plant, all right and wrong are intelligent, and its power consumption is big, efficient is low, noise is high, because motor speed is non-adjustable, so make it the frequent shutdown start, temperature control curve is unsmooth, does not have the function of automatic environment-identification.

The purpose of this utility model is in order to overcome above-mentioned weak point of the prior art, microcomputer is applied in the frequency conversion control circuit, adopt motor and the compressor that matches with frequency conversion control circuit simultaneously, thereby the automatic environment-identification condition of a kind of energy is provided, changes the motor compressor frequency automatically, reach automatic output best power, realize that efficient, energy-conservation, noise elimination and temperature control the intelligent frequency-conversion refrigerating plant of steady purpose.

The purpose of this utility model is achieved in that it comprises motor, compressor, frequency converter, wherein the major loop of frequency converter is made of rectification circuit, three phase inverter bridge, drive circuit three parts, the input and the power supply of rectification circuit join, the PN end of output and three phase inverter bridge joins, the input of drive circuit and the control circuit of frequency converter join, the input of output and three phase inverter bridge joins, and the output and the motor of three phase inverter bridge join.The control circuit of frequency converter is a core with 8098 single-chip microcomputers, the P of 8098 single-chip microcomputers ₃Mouth joins with the data wire of memory 2764, and the least-significant byte address bus by latch 373 and memory 2764 joins the P of 8098 single-chip microcomputers simultaneously ₄Mouth joins with the high address bus of memory 2764, three tunnel outputs of the high-speed output hso of 8098 single-chip microcomputers are joined with three road inputs of driver 7407 in the same way, three road inputs in addition through

phase inverter

7404 and 7407 join simultaneously, the output of driver 7407 joins by the input of

driver

7414,74365 and drive circuit in the same way, temperature sensor joins through the A/D mouth of

amplifier

7650 and 8098 single-chip microcomputers, the P of 8098 single-chip microcomputers ₂₀Mouth joins with the public control end of driver 74365.The holding circuit of frequency converter comprises that major loop current foldback circuit, electrical network are crossed, under-voltage protecting circuit, main circuit power device overtemperature protection circuit; the output of described holding circuit all joins with the input of NAND gate circuit; the output of NAND gate circuit divides two-way; the middle fracture EXTIN of one tunnel and 8098 single-chip microcomputers joins, and the public control end of another road and driver 74365 joins.

Of the present utility model is the control circuit of the frequency converter of core composition with 8098 single-chip microcomputers, output pwm pulse waveform, control three phase inverter bridge by drive circuit then and carry out switch clocklike, efficiently sinusoidal wave thereby the switching signal of output has formed three-phase PWM, be used for the drive motors rotation.

The utility model compared with prior art, because with 8098 single-chip microcomputers is the best combination of frequency converter with the corresponding motor and the compressor of core, and used advanced control software, so that the effect that this refrigerating plant has reached intelligent, volume is little, noise elimination is energy-conservation, control is steady, power factor is high.

The drawing explanation of accompanying drawing:

Fig. 1 is a schematic diagram of the present utility model.

Fig. 2 is the major loop and the holding circuit figure of frequency converter of the present utility model.

Fig. 3 is the control circuit figure of frequency conversion of the present utility model.

Fig. 4 is a software control block diagram of the present utility model.

Embodiment is described in further detail the utility model below in conjunction with (accompanying drawing).

The utility model is made up of the major loop of frequency converter and drive circuit, the control circuit of frequency converter, holding circuit, temperature sensor, motor, compressor.Civil power three-phase 380V power supply is input to the UR rectifier bridge of frequency converter major loop by RST, makes to exchange to become direct current, passes through R ₁To capacitor C ₀₁, C ₀₂K closure after 1 second is treated in charging, and the DC voltage behind the rectifying and wave-filtering is offered three phase inverter bridge GTR _1-6PN end.By 8098 single-chip microcomputers is the pwm pulse signal of the control circuit output that constitutes of core, is input to drive circuit D by plug wire spare X _rPhotoelectrical coupler isolate driver D _rThe pwm pulse ripple that sends according to control circuit drives GTR _1-6Three phase inverter bridge, make it switch clocklike, thereby differ 120 °, the three-phase PWM equivalent sine wave of frequency adjustable, voltage variable by U, V, W output, this frequency is 30-165HZ, drive motors rotation, corresponding motor speed are that 1000-3300 changes, and this motor adopts neodymium iron boron three-phase magnetic-synchro motor, drive compressor operating, this compressor adopts the vortex type compressor thereupon.Frequency conversion control circuit of the present utility model is a core with 8098 single-chip microcomputers, and program software is solidificated in the memory 2764, thereby has improved the reliability and the antijamming capability of this system.The P of 8098 single-chip microcomputers ₃Mouth joins with the data wire of memory 2764, makes data/address bus P _3-0-P _3-7With 2764 D ₀-D ₇Carry out both-way communication, simultaneously P ₃Mouth joins by the least-significant byte address bus of latch 373 with memory 2764, makes P ₃Mouthful with 2764 A ₀-A ₇Carry out the address communication, 8098 P ₄Mouth joins with the high address bus of memory 2764, makes P ₄Mouthful with 2764 A ₈-A ₁₃Address wire is carried out alternately.The PWM three-phase sine-wave that native system software generates, three road outputs by the high-speed output hso of 8098 single-chip microcomputers, be input to three road inputs in addition of driver 7407 in the same way, be input to three road inputs in addition of driver 7407 in the same way through phase inverter 7404 simultaneously, the output of driver 7407 is imported PWM three sinusoidal wave control signals by

driver

7414,74365 and plug connector X to drive circuit in the same way.Temperature sensor CU50 temperature signal after amplifier 7650 is amplified, be input to the A/D mouth of 8098 single-chip microcomputers, compare through data acquisition conversion of A/D mouth and design temperature, when the room temperature that sensor CU50 records is higher than setting value or is lower than setting value, control by software, export suitable frequency with the control compressor, make room temperature reach setting value by computer, and the thermostatic control of realization best power, its software work principle is as shown in Figure 4.Frequency converter holding circuit of the present utility model; major loop current foldback circuit wherein detects the main circuit current signal by the FL current divider; send into the NAND gate input through optocoupler; when overcurrent or short-circuit signal occur; make the NAND gate output low level; this signal stops the output except that blocking driver 74365 immediately, also signal is delivered to simultaneously the middle fracture EXTIN of 8098 single-chip microcomputers, makes 8098 SHO mouth stop to export.Electrical network is crossed, under-voltage protecting circuit is made up of signal circuit and comparison circuit, and line voltage is through T ₁Behind the step-down rectifier, pass through W ₁Obtain the signal voltage that is directly proportional with it and send into comparison circuit, compare with reference voltage again, when signal voltage is higher than reference voltage ref ₁The time, comparator C OM ₁Output low level quits work frequency converter to the NAND gate input, when signal voltage is lower than reference voltage ref ₂The time, comparator C OM ₂Output low level also makes frequency converter quit work to the NAND gate input.The main circuit power device overtemperature protection circuit passes through comparator C OM to heat alarm by the thermal relay that is installed on the radiator ₃Compare, when temperature surpassed 85 ℃, thermal relay continued action, COM ₃Output low level quits work frequency converter to the NAND gate input.

Claims

1, a kind of intelligent frequency-conversion refrigerating plant comprises motor, compressor, frequency converter, it is characterized in that:

The major loop of a, frequency converter comprises rectification circuit, three phase inverter bridge, drive circuit, the input and the power supply of rectification circuit join, the PN end of output and three phase inverter bridge joins, the input of drive circuit and the control circuit of frequency converter join, the input of output and three phase inverter bridge joins, and the output and the motor of three phase inverter bridge join;

The control circuit of b, frequency converter is a core with 8098 single-chip microcomputers, the P of 8098 single-chip microcomputers ₃Mouth joins with the data wire of memory 2764, and the least-significant byte address bus by latch 373 and memory 2764 joins the P of 8098 single-chip microcomputers simultaneously ₄Mouth joins with the high address bus of memory 2764, three tunnel outputs of the high speed output HSo of 8098 single-chip microcomputers are joined with three road inputs of driver 7407 in the same way, three road inputs in addition through phase inverter 7404 and 7407 join simultaneously, the output of driver 7407 joins by the input of driver 7414,74365 and drive circuit in the same way, temperature sensor is through several the joining of A/D of amplifier 7650 and 8098 single-chip microcomputers, the P of 8098 single-chip microcomputers ₂₀Mouth joins with the public control end of driver 74365;

The holding circuit of c, frequency converter comprises that major loop current foldback circuit, electrical network are crossed, under-voltage protecting circuit, main circuit power device overtemperature protection circuit; the output of described holding circuit all joins with the input of NAND gate circuit; the output of NAND gate circuit divides two-way; the middle fracture EXTIN of one tunnel and 8098 single-chip microcomputers joins, and the public control end of another road and driver 74365 joins.

2, intelligent frequency-conversion refrigerating plant according to claim 1 is characterized in that program controlled software is solidificated in the memory 2764.

3, intelligent frequency-conversion refrigerating plant according to claim 1 is characterized in that motor is the neodymium iron boron three-phase permanent magnet synchronous motor.

4, intelligent frequency-conversion refrigerating plant according to claim 1 is characterized in that compressor is the vortex type compressor.