CN203951370U - A kind of new type inverter - Google Patents

Abstract

The utility model relates to a kind of new type inverter, comprises rectification unit, filtering and inversion unit, control unit, and rectification unit, filtering are connected successively with inversion unit, control unit, and rectification unit becomes direct voltage alternating voltage; Filtering and inversion unit filtering part wherein carries out filtering the larger alternating current of pulsation and becomes level and smooth direct current; Converting Unit converts again three-phase alternating current to direct current, utilizes power switch component according to the driving of control circuit, the modulated PWM ripple of output pulse width, or Sine Pulse Width Modulation ripple; Control unit is used for producing the needed signal that respectively drives of output inverter bridge; In rectification unit inside, direct current reactor is housed.The beneficial effect of new type inverter described in the utility model is: be conducive to realize energy-conservation, guarantee constant product quality, conveniently control, be conducive to realize and automatically realize the product that performance is higher; Can utilize frequency converter to realize soft start, improve fail safe, extend equipment life.

Description

A kind of new type inverter

Technical field

The utility model relates to converter technique and microelectric technique, relates in particular to a kind of new type inverter.

Background technology

Frequency converter is application converter technique and microelectric technique, controls the electric control appliance of alternating current motor by changing machine operation supply frequency mode.Frequency converter is mainly comprised of rectification (AC-DC), filtering, inversion (direct current becomes interchange), brake unit, driver element, detecting unit microprocessing unit etc.; voltage and the frequency of cut-offfing to adjust out-put supply of the inner IGBT of portion of frequency converter; according to the actual needs of motor, provide its needed supply voltage; and then reach object energy-conservation, speed governing; in addition; frequency converter also has a lot of defencive functions, as overcurrent, overvoltage, overload protection etc.Along with improving constantly of industrial automatization, frequency converter has also obtained application very widely, main circuit is that the power converter part of voltage regulation and frequency modulation power supply is provided to asynchronous motor, the main circuit of frequency converter can be divided into two classes substantially: voltage-type is the frequency converter for exchanging by the DC converting of voltage source, and the filtering of DC loop is electric capacity; Current mode is the frequency converter for exchanging by the DC converting of current source, its DC loop filtering is inductance, it consists of three parts, power frequency supply is transformed to " rectifier " of direct current power, be absorbed in current transformer and inverter produce mains ripple " flat ripple loop ".

But, because the overload capacity of frequency conversion does not have motor overload ability strong, once motor has overload, first what damage is frequency converter, if the power of motor of having selected on equipment is greater than actual machine bearing power, but likely user can will be adjusted to mechanical output to reach output power of motor, now, frequency converter must be competent at, and the power that is to say frequency converter is selected and must be equal to or greater than power of motor.In conjunction with above, analyze the following aspects problem that often exists of existing frequency converter: 1. environment for use condition, line voltage, load and character; 2. ambient temperature is higher for a long time, while being arranged in the cooling bad rack that ventilates, can cause the frequency converter lost of life, the devices such as electronic device, particularly electrochemical capacitor, after higher than rated temperature, every rising 10 ℃ of life-spans can drop by halfs, so ambient temperature should keep lower, except perfect ventilation cooling system being set to guarantee the normal operation of frequency converter, on selecting, increase a capacitance grade, so that during specified operation, temperature rise declines to some extent and is completely necessary; 3. line voltage, when undesired, will be harmful to frequency converter, and overtension, as the line voltage to 380V will cause damage as risen to 450V; 4. high altitude localities reduces because of atmospheric density, and radiator can not reach specified radiator effect, generally more than 1000m, and every increase 100m capacity loss 10%; While being 5. used in different purposes, for general service frequency converter, adopt V/F=constant control mode can meet, large for load variations scope, and the occasion of the running accuracy of having relatively high expectations again, while particularly requiring to have stable speed and load capacity during low speed, will select the frequency converter of the modes such as vector control, to precision drive such as Digit Control Machine Tools, also will adopt the mode of closed-loop control and speed sensor, corresponding frequency converter also will have the interface of these cooperations; 6. frequency converter uses different places will elect to the degree of protection of frequency converter, and common IP10, IP20, IP30, IP40 grade can prevent that respectively Ф 50, Ф 12, Ф 2.5, Ф 1 solids from entering; 7. when frequency converter resets highlyer by modulating frequency and surpasses Default Value frequency for reducing electric moter noise, can cause frequency converter loss to increase, frequency is set higher, loss is larger, therefore want suitable off-load, increase simply modulating frequency, cause frequency converter overheated and damage, or frequency converter is defeated does not go out rated power; 8. vector control mode can only motor of a corresponding transducer drive, and the rated current of frequency converter should be equal to or greater than motor rated current, and the actual use electric current of motor can not be too less than rated current; 9. during a transducer drive multiple electric motors, frequency inverter capacity should be larger than multiple electric motors capacity sum, and can only select V/F control model, can not use vector control pattern; 10. when the inversion unit of many frequency converters shares a rectification/feedback unit, adopt common DC bus mode, be conducive to storage and the utilization of many inverter braking energies, now the capacity of rectification/feedback unit wants enough large, and to have the measure that prevents that Small-power Inverter rectifier bridge overload from damaging, in use, to multiple electric motors, can not brake simultaneously; (11) to the load of blower fan water pump class, as original use valve, air door adjust flux, when using speed govornor by frequency modulator flow instead, will bring significantly energy-conservationly, and the load of friction class is used the energy-saving effect of frequency control substantially can not embody.

The universal frequency converter of this case refer to be applicable to industrial general motor and general variable-frequency motor and by general mains supply (single-phase 220V, three-phase 380V 50Hz), make the frequency converter of speed regulating control, this type of frequency converter is due to the main flow that becomes frequency converter that is widely used of industrial circle.Therefore,, for above aspect, need to reasonably improve prior art.

Summary of the invention

For above defect; the utility model provides a kind of noise that is conducive to reduce motor, can reduce leakage current that output high order harmonic component causes, reduced interference, can protect the device for power switching of frequency converter inside, the new type inverter that is conducive to extend the electrical machine insulation life-span, to solve many deficiencies of prior art.

For achieving the above object, the utility model is by the following technical solutions:

A new type inverter, comprises rectification unit, filtering and inversion unit, control unit, and rectification unit, filtering are connected successively with inversion unit, control unit, and rectification unit wherein becomes direct voltage alternating voltage; Filtering and inversion unit filtering part wherein carries out filtering the larger alternating current of pulsation and becomes level and smooth direct current; Converting Unit converts again three-phase alternating current to direct current, utilizes power switch component according to the driving of control circuit, the modulated PWM ripple of output pulse width, or Sine Pulse Width Modulation ripple; Control unit is used for producing the needed signal that respectively drives of output inverter bridge;

Correspondingly, in rectification unit inside, direct current reactor is housed, in filtering and inversion unit outer setting, control power supply auxiliary input circuit and this circuit with three switches, between filtering and inversion unit and control unit, frequency setting potentiometer is installed, this potentiometer and the input of frequency setting electric current, analog frequency meter join, be positioned at a digital frequency meter pulse-scaling circuit of control unit outer end access, some contact input signal ends are set between this counting circuit and frequency setting potentiometer.

Described control unit output arranges RS485 communication interface; Direct current reactor connects respectively outside brake resistance part, brake unit by circuit.

The beneficial effect of new type inverter described in the utility model is:

(1) by rectifying part, filtering part, Converting Unit and four the electric circuit constitutes of control circuit, rectifying part becomes direct voltage alternating voltage; Filtering part carries out filtering the larger alternating current of pulsation and becomes smoother direct current; Converting Unit converts again three-phase alternating current to direct current, this inverter circuit is generally to utilize power switch component according to the driving of control circuit, the modulated PWM ripple of output pulse width, or Sine Pulse Width Modulation ripple, when the voltage of this waveform is added in load, due to load inductance effect, make current continuity, become the current waveform that approaches sine; Control circuit is for producing the needed signal that respectively drives of output inverter bridge; these signals are determined by external command, have the Comprehensive Control of frequency, frequency rise and fall speed, the control of outside break-make and the inner various protections of frequency converter and feedback signal etc.

(2) this frequency converter is all bipolar SPWM ripple to the output waveform of load, this waveform can increase substantially the efficiency of frequency converter, by regulating this frequency converter, be conducive to realize energy-conservation, guarantee constant product quality, conveniently control, be conducive to realize full-automatic and realize the product that performance is higher; Can utilize frequency converter to realize soft start, improve fail safe, extend equipment life.

Accompanying drawing explanation

With reference to the accompanying drawings the utility model is described in further detail below.

Fig. 1 is the theory of constitution schematic diagram of new type inverter described in the utility model embodiment;

Fig. 2 is the control circuit part schematic diagram of new type inverter described in the utility model embodiment;

Fig. 3 is the additional corollary equipment connection diagram of the frequency converter of new type inverter described in the utility model embodiment;

Fig. 4 is the outlet side AC reactor sectional schematic diagram of new type inverter described in the utility model embodiment;

Fig. 5-34th, each application state of this case and annexation schematic diagram and Fig. 5-34 are corresponding successively with this case application of frequency converter example 1-30.

In figure:

1, rectification unit; 2, filtering and inversion unit; 3, control unit.

Embodiment

As shown in Figure 1-2, new type inverter described in the utility model embodiment, comprise rectification unit 1, filtering and inversion unit 2, control unit 3, rectification unit 1 wherein becomes direct voltage alternating voltage, and filtering and inversion unit 2 filtering part wherein carries out filtering the larger alternating current of pulsation and becomes smoother direct current; Converting Unit converts again three-phase alternating current to direct current, utilize power switch component according to the driving of control circuit, the modulated PWM ripple of output pulse width, or Sine Pulse Width Modulation ripple, when the voltage of this waveform is added in load, due to load inductance effect, make current continuity, become the current waveform that approaches sine; Control unit 3 is used for producing the needed signal that respectively drives of output inverter bridge, and these signals have the Comprehensive Control of frequency, frequency rise and fall speed, the control of outside break-make and the inner various protections of frequency converter and feedback signal etc.;

Correspondingly, in rectification unit 1 inside, direct current reactor is housed and this direct current reactor connects respectively outside brake resistance part by circuit, brake unit, in filtering and inversion unit 2 outer setting, control power supply auxiliary input circuits and this circuit with three switches, between filtering and inversion unit 2 and control unit 3, frequency setting potentiometer is installed, this potentiometer and the input of frequency setting electric current, analog frequency meter joins, be positioned at a digital frequency meter pulse-scaling circuit of control unit 3 outer end accesses, some contact input signal ends are set between this counting circuit and frequency setting potentiometer, these control unit 3 outputs arrange RS485 communication interface, concrete control unit 3 interior contacts input signal terminal circuits connect as shown in Figure 2.

As shown in Figure 3, the new type inverter described in the utility model embodiment, for the connection of the additional corollary equipment of frequency converter, wherein,

T-distribution transformer;

QF-circuit breaker, disconnects electrical network for safety tripping operation;

KM-contactor, while sending a telegram here for regular job break-make and electric network power-fail there is not self-starting in frequency converter again;

FIL1-inlet wire side radio interference suppresses reactor, for reducing frequency converter radio interference to external world;

1ACL-mains side AC reactor, for improving input current waveform, improve rectifier and electrolysis filter capacitor life-span, reduce bad input current waveform to external world electrical network interference, the waveform influence of coordinating to have the converters such as thyristor cause on same power net, reduce that power switches and the impact of three-phase imbalance, therefore also make power supply coordinate reactor, requiring this reactor of high occasion just further to change more complicated power quality filter unit into;

DCL-direct current reactor, be used for improving the input current waveform distortion that capacitor filtering (the main filtering mode of current voltage type variable-frequency governor is capacitor filtering) causes and improve power factor, reduce and prevent because of impulse current cause rectifier bridge to damage and electric capacity overheated, when power transformer and the comprehensive internal resistance of power transmission line (the symbol DLC in figure should change DCL into) hour when more than 10 times (transformer capacity be greater than capacity motor), electrical network transition all need to use direct current reactor when frequent.

BD-brake unit, when frequency converter reduction frequency makes motor abrupt deceleration or gravity load make motor in generator operation, the feedback energy of motor braking is elevated to a certain degree frequency changer direct current bus voltage will open this brake unit, and consumption of energy is in brake resistance;

DBR-brake resistance, the resistance of motor power while consuming braking;

2ACL-outlet side AC reactor, frequency converter output be pulse width modulation voltage wave (PWM ripple) it be before and after along a very steep series impulse square wave, there is abundant harmonic wave, the life-span that these harmonic waves are harmful to motor and load (is typically motor winding turn-to-turn transient voltage dv/dt too high, cause breakdown between adjacent turns), and to electrical equipment interference around; When load end capacitive component is large, cause the switching device of frequency converter to flow through large impulse current, can damage switching device.

FIL2-outlet side radio interference suppresses reactor, during to output wiring distance >20m, especially needs to install;

JR-thermal overload relay, for preventing that long-time overcurrent from causing motor to damage.

Circuit breaker (QF) below can connect one or more frequency converter and other load, when frequency converter or other load are during because of overcurrent fault, can automatic cut-off power power supply, Accident prevention expands.The dangerous of connection automatically prevents from sending a telegram here when electric network power-fail again, and at when maintenance safety cut-off power supply, circuit breaker can be used the circuit breaker of normal air switch or highly sensitive cut-out, depends on the needs, and while selecting, always by electric current, should be greater than load total current more than 1.5 times;

Contactor (KM) is for controlled frequency converter regular job break-make, and electric network power-fail prevents that frequency converter from starting automatically while sending a telegram here again, and while selecting, rated current is also greater than frequency converter output current more than 1.5 times;

Radio interference inhibition reactor (FIL1, FIL2) is PWM (pulse-width modulation) ripple because of frequency converter output, comprised a large amount of high order harmonic components, harmonic wave high fdrequency component is in radio-frequency region, and frequency converter is outwards launched radio interference by power line and output line.Again because frequency converter is connected on electrical network, there is misoperation in the responsive part of control loop that on electrical network, various interference and transition surge also can interfere with frequency converter, is therefore provided with radio interference and suppresses reactor.It is use three inlet wires (to single-phase be two inlet wires), the inductance of equidirectional coiling on iron core or iron oxygen magnetic core, the sinusoidal ac instantaneous value sum of three lines of the three characteristics of the middle term is zero (single-phase sinusoidal ac two inlet wire current instantaneous values is also zero), therefore to normal power supply, this reactor is inoperative, and play barrier effect for this reactor of common-mode voltage (interference voltage occurring, instantaneous value can not be cancelled) on inlet wire, suppressed common mode disturbances, played good inhibition radio interference and use.The frequency range suppressing is generally below 10MHz, so inductance value needn't be large, is conventionally controlled at 2 ~ 33mH left and right, be on a closed magnetic circuit through or around on a few circle wires and making.Radio interference suppresses the connection of reactor as Fig. 8, to low capacity frequency converter because of electric current less, it is on same magnetic core, triple line is equidirectional around several circles.To large-capacity transducer, because electric current is large, wire is bad curved, use a plurality of magnetic cores, allow three wires through magnetic core mesopore, form reactor simultaneously.

Voltage-type universal frequency converter line voltage exchange change into direct current after rectification all through capacitor filtering, the use of capacitor makes input current be spike shape, when electric network impedance hour, this spike electric current is very big, cause very large humorous wave interference, and frequency converter rectifier bridge and capacitor are easily damaged.When transformer capacity is greater than frequency inverter capacity more than 10 times, when the internal resistance of electrical network distribution transformer and power transmission line can not stop spike electric current, while having thyristor equipment or on-off mode power ratio control factor compensation device on same power supply, when three phase mains degree of unbalance is greater than 3%, all to input side power factor be done to improve and be suppressed and disturb, all need to use mains side AC reactor.

Generally speaking, the inductance value of voltage source inverter, mains side AC reactor, adopts 3% impedance can prevent that mutation voltage from causing contactor tripping operation, makes total harmonic current distortion drop to 44% original left and right.In actual use, for cost saving, often adopt the inductance value of 2% impedance, but this is bad for environmental protection.Reasonable occasion should be used 4% impedance or larger reactor.

Direct current reactor is connected on before filter capacitor, the amplitude of impulse current after the rectification of its entry deterrence electric capacity, and improve power factor, reduction bus interchange pulsation.Direct current reactor advises all will adopting when transducer power is greater than 22kW, when transducer power larger, more should use, because while there is no direct current reactor, the capacitor filtering of frequency converter can cause the serious distortion of current waveform and and then grid voltage waveform is seriously distorted, and the rectifier bridge of the frequency converter that does serious harm on and filter capacitor life-span.The selection of the inductance value of direct current reactor is generally 2 ~ 3 times of same frequency converter input side AC reactor 3% impedance inductance value, minimumly wants 1.7 times,

The output of frequency converter is the voltage wave through PWM modulation, because the inductive mass-energy of motor winding makes current continuity, therefore electric current is sine-shaped substantially, the edge, front and back that pulse width modulation (PWM) has precipitous voltage to rise and decline, be that dv/dt is very large, make output lead to the great electromagnetic interference of external world transmitting content, and lead-out wire over the ground, motor winding inter-turn, winding all produce very large pulse current between over the ground, Figure 10 represents SPWM voltage, the waveform of electric current.

In order to alleviate frequency converter output dv/dt interference to external world, reduce output waveform distortion, reach environmental protection standard, minimizing causes insulation damages to the voltge surge of motor winding, reduce temperature rise and the noise of motor, avoid on power converter output pipe because of dv/dt and flow through excessive pulse shock electric current power tube is damaged, and reduce load short circuits and cause the damage to frequency converter, be necessary to set up AC reactor at the defeated end of frequency converter.

It is worthy of note when pulse voltage is passed through long power transmission line, because wave reflection stack on long line makes to surpass after critical length at long line (being frequency converter output lead), voltage likely reaches 2 times of DC bus (DC bus in frequency converter) voltage.Therefore frequency converter output line length is restricted, for removing this restriction, and must access outlet side AC reactor.

As shown in Figure 4, wire on the magnetic core position relationship end to end that is wound on of outlet side AC reactor is outwards launched the big or small degree of interfering energy to inductance, winding head is at nexine, tail is at skin, therefore it is better that the output that connects frequency conversion connects load motor, like this, the strong jamming of inverter output terminal is shielded by skin, reduces and disturbs outwards transmitting.

Small-power brake unit is generally inner at frequency converter, and outside only connects brake resistance.Powerful brake unit is received on frequency converter bus by external brake unit, when motor braking, the electric energy of motor feeds back to bus, busbar voltage is raise, while being elevated to certain value, open the switching tube of brake unit, by brake resistance, consume last minute electric energy of bus, maintain busbar voltage and do not continue up to raise, make motor power consumption in brake resistance, thereby obtain braking moment.The conductor length of brake unit is generally not more than 5m, and the DC bus (P+, N end) of receiving frequency converter will be used twisted-pair feeder or adherence parallel lines, its objective is minimizing inductance, and the cross section of wire should be not less than 1/2～1/4 of motor power transmission line.

The outside wiring of frequency converter: (1) major loop wire section is according to motor wiring requirement, and current density is generally below 3～4A/mm2;

(2) when the major loop wire of R, S, T and U, V, W is protected wiring in iron pipe, must not one or two conductor layings in an iron pipe, three line cloth of necessary three-phase are in same iron pipe, this is because sinusoidal wave three-phase current instantaneous value sum is zero, can on iron pipe, not cause magnetic flux to generate heat with causing loss;

(3) frequency converter output U, V, tri-lines of W are as applied not in iron pipe and snakeskin metal tube, because of the effect to iron pipe and flexible metal conduit electric capacity, can cause the transient pulse overcurrent of frequency converter internal power switching device, power switch is damaged, and generally when length of arrangement wire surpasses 30m (having pipe)～50m (without pipe), U, V, the W terminal place of frequency converter need insert AC reactor; If wire insulation is thinner, length of arrangement wire also should be shorter; When an a plurality of motor of transducer drive, should calculate by the total length of distribution; After access outlet side AC reactor, feedback does not surpass 400 m to the total length of motor yet;

(4) control line of frequency converter must be away from input and output forceful electric power wire, at a distance of more than 100mm, can not attractive in appearance control line and input and output forceful electric power wire be bundled in order to connect up;

(5) input signal cable of frequency converter will be used twisted-pair feeder or shielding conductor, the interference causing effectively to weaken external electromagnetic field, and multiple twin cabling degree should be more than 1 strand at every cm;

(6), when far distance controlled is done switching manipulation, with relay, serve as intermediary operation and can effectively reduce the interference that outer bound pair control line causes;

(7) together with the operation keys of most frequency converters is done with display section, become an operating case, operating case can take off does remotely-controlled operation, now connect wire cable or winding displacement often, require them away from power line and input and output forceful electric power wire, should penetrate if desired in shielding pipe box, outside electrical equipment control line also needs shielding when very long, and method is identical;

(8) when thick major loop electric wire is with transducer terminal sub-connection, must reliably be connected, the cold end terminal matching with binding post of standard for the end of a thread, is used cord end plier crimping;

(9) potentiometer of regulating frequency etc., switch and so on components and parts require to use Reliable Products, and note shielding while installing, and avoid external interference, otherwise can think that frequency converter has problem by mistake;

(10) all connecting lines will check after connecting, prevent from missing, misconnection, touch ground, short circuit;

(11) drop into after power supply, while finding also to want reconfiguration line, first will excise power supply, and notice that the electricity on DC loop electric capacity discharges (D.C. voltmeter measurement is less than 25V) completely, just can operate;

(12) power-factor of load can not proofreaied and correct to the output that receive frequency converter with electric capacity, because the access of electric capacity can cause inverter power device to flow through large ringing pulse electric current, damage;

(13) parameter of direct current reactor will match with frequency converter, should remove the short circuit copper part on former P1, P+ on frequency converter before installation, accesses herein direct current reactor;

(14) female wire of brake unit is received the DC bus (P+, N end) of frequency converter, the wiring of brake unit and brake resistance is all as far as possible short, length is not more than 5m, uses twisted-pair feeder or adherence parallel lines, and the cross section of wire should be not less than 1/2～1/4 of motor power transmission line;

(15) shell of frequency converter is answered reliable ground.

Debugging after frequency converter is installed:

Before energising, check: watch frequency converter installing space, ventilation situation, whether enough safely; Whether nameplate mates with motor; Whether control line is rationally distributed, to avoid interference; Inlet wire and outlet absolutely not must connect instead, and the internal main loop negative terminal N of frequency converter must not receive on electrical network center line, and each control line wiring should be correct.

Conductor length between frequency converter and motor surpasses about 50m, when this wire cloth length in iron pipe or flexible metal conduit surpasses about 30m, the situation such as transducer drive multiple electric motors particularly, distributed capacitance is very large over the ground frequency converter output lead, should on inverter output terminal, first connect AC reactor, then receive on wire below, it is finally load, in order to avoid excessive capacitance current damages inversion module, when outlet side wire is long, also the modulated carriers of PWM to be arranged on to low frequency, to reduce the heating of power output pipe, to reduce the probability damaging.

Confirm that frequency converter operating state and the mutual switching of power frequency operating state will have the interlocking of contactor, can not cause short circuit, and motor steering is identical during two kinds of use states;

According to factors such as frequency inverter capacities, confirm whether input side AC reactor and filtering direct current reactor access;

Whether the mains supply phase shortage that do not have, measure grid ac voltage and current value, control magnitude of voltage etc. at setting.

As shown in Fig. 5-34, be each application state of this case and annexation:

this case application of frequency converter example 1

Application on dust suction forced draft fan: if utilize micro-pressure-difference signal driver frequency converter to run slowly, annual only needs 60% electric energy operation, has realized energy-conservation.

this case application of frequency converter example 2

On central air-conditioning forced draft fan, apply: with pressure sensor (DC 4-20MA), keep blast in pipeline, on average as long as 50% operation has realized energy-conservation.

this case application of frequency converter example 3

On cooling tower, apply: utilize humidity sensor to adjust frequency converter, make blower fan adjustment, average needs 40% running, realize energy-conservation.

this case application of frequency converter example 4

On water supply pump, apply: setting pressure transducer on the output channel of pump, regulate frequency converter, make pump only need average 85% running, realized energy-conservation.

this case application of frequency converter example 5

On the forced draft fan of drying machine, apply: by mixed humidity in sensing chamber, the blower fan of frequency converter is carried out to equilibrium and regulate, make constant product quality.

this case application of frequency converter example 6

In agricultural and animal husbandry, apply: in order regulating and ventilation chamber is wet, to have used a plurality of fans, by Frequency Converter Control, can to have obtained and cultivate feeding environment optimization.

this case application of frequency converter example 7

On industrial washer, apply: use frequency converter according to the material of washing, quantity, to change the rotating speed of scrubber, be transferred at a high speed during dehydration, convenient control, has realized full-automatic.

this case application of frequency converter example 8

In food industry, apply: use frequency converter can control the parameters such as process time, make the best in qualityly, production efficiency is the highest.

this case application of frequency converter example 9

On noodle machine, apply: use the frequency converter can be according to the amount of rolling of milling roller adjusting rotary speed easily, realize automatically, product quality improves.

this case application of frequency converter example 10

On mixer, apply: use frequency converter to remove adjusting rotary speed according to material, product quality is improved.

this case application of frequency converter example 11

On dry heat processor, apply: for making indoor humidity even, a plurality of fans of Frequency Converter Control again, wind speed inhomogeneities reduces, and can obtain high performance product.

this case application of frequency converter example 12

On fiber industry machine, apply: the shuttle speed of spinning to different materials, with frequency converter, regulate, improve the quality of products.

this case application of frequency converter example 13

Cleaning, on dewaterer, apply: when changing speed, can utilize frequency converter to realize soft start, slow stop etc., has improved fail safe.

this case application of frequency converter example 14

On hopper, apply: at raw material supplying, use frequency converter can reach high-precision cooperation with coordinating of line speed.

this case application of frequency converter example 15

On plait mill, apply: use frequency converter according to coiled strip tensioning situation, to regulate easily the rotating speed of each motor, realize coiled strip process full-automatic, product quality is improved.

this case application of frequency converter example 16

Blower fan, water pump class Flow-rate adjustment: use the energy consumption of having avoided resistance gauges such as valve (blower fans) to cause after frequency converter, can realize amplitude peak energy-conservation.After using adjuster, can realize stability of flow output, easily realize flow and automatically control.

this case application of frequency converter example 17

In constant pressure water supply, apply: working pressure transmitter, PID adjuster are realized after negative feedback frequency converter, and frequency converter is adjusting rotary speed at any time, make the output pressure of pump stable, saved water tower and additional construction cost; Promote in large flow process class technology controlling and process, can realization flow Auto-control of the process, use gloomy blue frequency converter also can realize many pumps and control.

this case application of frequency converter example 18

On ribbon conveyer, apply: can realize stepless speed regulation; After the transducer of use location, can realize the control of speed change degree pendulum and start and stop automatic control; Select frequency converter to be equal to or greater than power of motor, while carrying, should consider regenerative braking downwards.

this case application of frequency converter example 19

The application that powder is carried: utilize the electric current I that detects mixer motor, feed back and set-point comparison, control frequency converter, make conveyor motor adjusted; Increase work efficiency, can realize unmanned operation; Device security increases substantially.

this case application of frequency converter example 20

Plate rolling roller speed governing application: by a Frequency Converter Control multiple electric motors, realize synchronous operation, make speed easy to adjust, realize same-phase, start and stop are steady, greatly improve quality and the efficiency of plate rolling.

this case application of frequency converter example 21

Dyeing machine Synchronization Control: use sliding roller to obtain sync signal, remove to regulate frequency converter, make the cloth tensioning degree of each operation in printing and dyeing consistent, reach synchronous; With frequently moving the precision that makes to print and dye, increase substantially; Realize auto-control, overcome the difficulty of artificial adjustment.

this case application of frequency converter example 22

On air-condition cooling tower, apply: cooling tower electric machine, according to cooling water temperature variable-speed operation, makes cooling water temperature balance; The comfortableness of air-conditioning improves; Low noise, extend equipment life.

this case application of frequency converter example 23

Ventilating system automatic control application: utilize temperature sensor feedback indoor temperature, act on fan of frequency converter motor, make indoor temperature maintain normal value, ventilation constant temperature, comfortable, power saving, low noise.

this case application of frequency converter example 24

Machine tool chief axis speed governing: to requiring the lathe of main shaft speed governing can reach stepless speed regulation with frequency converter, the synchronizing speed that speed can determine higher than mains frequency; The little lathe of torque while being applicable to low speed, but when low speed torque is large, need mechanical transmission to change torque; Stepless speed regulation is steady, and precision is high, arranges simple.

this case application of frequency converter example 25

Application on elevator: use PLC to control frequency converter output frequency and phase sequence, can make easily elevator upper and lower, and press S type curve motion, do not impact; The comfortableness of elevator improves; Elevator speed improves.

this case application of frequency converter example 26

On plastic extruder, apply: the outlet of plastic extrusion has pressure, transducer feeds back to adjuster and frequency converter by extrusion pressure, adjusts the rotating speed of extruder main spindle motor, thereby steady pressure guarantees product quality; System realizes continuously and regulating, and extrudes power stable; Simplified control, quality improves.

this case application of frequency converter example 27

Application on dance wire drawing machine: basic principle is similar with tension adjustment, every one-level kink draws this grade of frequency converter and regulates motor speed, and the wire second flow that reaches every one-level membrane equates, realizes serialization and produces; Greatly improve qualification rate, remove artificial adjustment from.

this case application of frequency converter example 28

On injection molding machine, apply: each operation of " close film, boost, inject, measurement, pressurize, rise film " in 1 circulation of injection mo(u)lding, the rotating speed of oil pressure pump constantly changes, and with frequency converter, can make that processing is stable, quality assurance, realize automation.

this case application of frequency converter example 29

Application on stock-cutter: change blank length according to the kind of food, purposes on stock-cutter, the speed that can change conveyer belt with frequency converter reaches, makes operating efficiency and cuts off accuracy and improve.

this case application of frequency converter example 30

Application on medicine equipment x-ray: for X-ray machine lifting, movement, locate, make to operate steadily, low noise, be applicable to hospital environment.

The above-mentioned description to embodiment is can understand and apply this case technology for the ease of those skilled in the art, person skilled in the art obviously can make various modifications to these examples easily, and General Principle described herein is applied in other embodiment and needn't passes through performing creative labour.Therefore, this case is not limited to above embodiment, and those skilled in the art is according to the announcement of this case, and the improvement of making for this case and modification all should be in the protection ranges of this case.

Claims (3)

1. a new type inverter, comprises rectification unit, filtering and inversion unit, control unit, it is characterized in that:

Rectification unit, filtering are connected successively with inversion unit, control unit, and rectification unit wherein becomes direct voltage alternating voltage;

Filtering and inversion unit filtering part wherein carries out filtering the larger alternating current of pulsation and becomes level and smooth direct current; Converting Unit converts again three-phase alternating current to direct current, utilizes power switch component according to the driving of control circuit, the modulated PWM ripple of output pulse width, or Sine Pulse Width Modulation ripple;

Control unit is used for producing the needed signal that respectively drives of output inverter bridge;

Correspondingly, in rectification unit inside, direct current reactor is housed, in filtering and inversion unit outer setting, control power supply auxiliary input circuit and this circuit with three switches, between filtering and inversion unit and control unit, frequency setting potentiometer is installed, this potentiometer and the input of frequency setting electric current, analog frequency meter join, be positioned at a digital frequency meter pulse-scaling circuit of control unit outer end access, some contact input signal ends are set between this counting circuit and frequency setting potentiometer.

2. new type inverter according to claim 1, is characterized in that: described control unit output arranges RS485 communication interface.

3. new type inverter according to claim 1, is characterized in that: described direct current reactor connects respectively outside brake resistance part, brake unit by circuit.