CN110953154A - Screw compressor work frequency conversion online switching system - Google Patents
Screw compressor work frequency conversion online switching system Download PDFInfo
- Publication number
- CN110953154A CN110953154A CN201911056554.2A CN201911056554A CN110953154A CN 110953154 A CN110953154 A CN 110953154A CN 201911056554 A CN201911056554 A CN 201911056554A CN 110953154 A CN110953154 A CN 110953154A
- Authority
- CN
- China
- Prior art keywords
- screw compressor
- frequency conversion
- frequency
- online switching
- starting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000006243 chemical reaction Methods 0.000 title claims abstract description 36
- 210000001503 joint Anatomy 0.000 claims description 6
- 238000000034 method Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 241000555745 Sciuridae Species 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000004753 textile Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C2240/00—Components
- F04C2240/40—Electric motor
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention discloses a screw compressor work frequency conversion online switching system, which comprises a frequency converter, an online switching module and an online switching unit, wherein the starting and running modes of a screw compressor are divided into two parts: the system comprises a variable frequency starting mode and a power frequency running mode, wherein the starting mode fully utilizes the characteristics of small variable frequency starting impact and low requirement on a user power supply; because the starting time is short, the influence on the harmonic wave of the power grid is greatly reduced, and the current is 1.2-1.5 times of the rated current when the frequency converter is started, the capacity of the frequency converter can be reduced, the operation mode can be applied, the structure is simple, the price is substantial, simultaneously, the power consumption of the frequency converter is reduced by 2-3%, the harmonic wave of the power grid is eliminated, the frequency conversion of the starting mode is switched to the power frequency of the operation mode, and the requirements of flexibility and adaptability are met.
Description
Technical Field
The invention relates to the related field of screw compressors, in particular to a screw compressor work frequency conversion online switching system.
Background
The screw compressor is a mechanical device with wide application, and is applied to the fields of machinery, metallurgy, textile, food and the like, and for a screw compressor, the flexibility and the adaptability of the use environment of the screw compressor are considered besides the self starting operation mode, and the existing starting operation mode of the screw compressor mainly comprises power frequency starting operation and variable frequency starting operation; the industrial frequency starting operation mode of the screw compressor adopts a star-delta voltage reduction starting mode, a stator winding of a squirrel cage motor adopts a star connection method during starting, a triangle connection method during operation is adopted, the industrial frequency starting operation mode of the screw compressor has 1/3 torque of rated torque during starting, 5-7 times of rated current during starting, and excessive starting current can cause the voltage of a power grid to be reduced, thereby possibly affecting the normal operation of other electric equipment and even causing the tripping of a user power supply, simultaneously causing the motor winding to generate heat, accelerating insulation aging and affecting the service life of the motor, therefore, the requirement on the user power supply is higher, and the light load and even no load during starting of the screw compressor are strictly limited, the variable frequency starting operation mode of the screw compressor has the torque of 0.7-1.2 times of the rated torque during starting and the current of 1.2-1.5 times of the rated current during starting, mechanical and electrical impact is small, the requirement on a user power supply is not high, the load when the screw compressor is started is wide and loose, but the frequency conversion starting operation mode of the screw compressor is not enough in cost, 2-3% of power consumption exists, and harmonic waves can be generated to a power grid.
Disclosure of Invention
Therefore, in order to solve the above-mentioned disadvantages, the present invention provides an online switching system for the duty cycle of a screw compressor.
The invention is realized in such a way that an online switching system for the working frequency conversion of the screw compressor is constructed, the device comprises a frequency converter, an online switching module and an online switching unit, wherein the frequency converter is used for being responsible for the frequency conversion starting of the screw compressor, the online switching module is used for being responsible for the control calculation of the online switching of the working frequency conversion of the screw compressor, and the online switching unit is used for being responsible for the implementation of the online switching of the working frequency conversion of the screw compressor.
Preferably, the frequency converter is in control butt joint with a motor of the screw compressor.
Preferably, the online switching module specifically controls and calculates a switching time point at which the variable frequency start is switched to the power frequency operation.
Preferably, the online switching unit is specifically switched to power frequency operation by frequency conversion starting.
Preferably, the online switching module is in control butt joint with the online switching unit.
Preferably, the online switching module monitors the phase of the user three-phase power supply and the phase of the three-phase voltage output by the frequency converter.
Preferably, the phase difference between the phase of the user three-phase power supply and the phase of the output three-phase voltage of the frequency converter is within +/-5 degrees.
The invention has the following advantages: the invention provides a screw compressor work frequency conversion online switching system through improvement, compared with the same type of equipment, the screw compressor work frequency conversion online switching system has the following improvement:
the invention discloses a screw compressor work frequency conversion on-line switching system, which divides the starting and running modes of a screw compressor into two parts: the system comprises a variable frequency starting mode and a power frequency running mode, wherein the starting mode fully utilizes the characteristics of small variable frequency starting impact and low requirement on a user power supply; because the starting time is short, the influence on the harmonic wave of the power grid is greatly reduced, and the current is 1.2-1.5 times of the rated current when the frequency converter is started, the capacity of the frequency converter can be reduced, the operation mode can be applied, the structure is simple, the price is substantial, simultaneously, the power consumption of the frequency converter is reduced by 2-3%, the harmonic wave of the power grid is eliminated, the frequency conversion of the starting mode is switched to the power frequency of the operation mode, and the requirements of flexibility and adaptability are met.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic diagram of the present invention, an I/O conversion on-line switching system;
FIG. 3 is an enlarged schematic view taken at A of FIG. 2 in accordance with the present invention;
FIG. 4 is an enlarged schematic view of the invention at B of FIG. 2;
FIG. 5 is an enlarged schematic view at C of FIG. 2 of the present invention;
fig. 6 is an enlarged schematic view at D in fig. 2 of the present invention.
Wherein: a frequency converter-11, an online switching module-12 and an online switching unit-13.
Detailed Description
The present invention will be described in detail below with reference to fig. 1 to 6, and the technical solutions in the embodiments of the present invention will be clearly and completely described, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a screw compressor work frequency conversion online switching system through improvement, which comprises a frequency converter 11, an online switching module 12 and an online switching unit 13, wherein the frequency converter 11 is used for being responsible for frequency conversion starting of a screw compressor, the online switching module 12 is used for being responsible for control calculation of screw compressor work frequency conversion online switching, and the online switching unit 13 is used for being responsible for implementation of screw compressor work frequency conversion online switching.
Furthermore, the frequency converter 11 is in control butt joint with a motor of the screw compressor, so that the screw compressor is started up and then the frequency converter 11 drives the motor to start up.
Further, the online switching module 12 specifically controls and calculates a switching time point at which the variable frequency start is switched to the power frequency operation.
Further, the online switching unit 13 is specifically switched to power frequency operation by frequency conversion starting.
Further, the online switching module 12 is in control butt joint with the online switching unit 13, so that the online switching module 12 can control the online switching unit 13 to operate.
Further, the online switching module 12 monitors the phase of the three-phase power of the user and the phase of the three-phase voltage output by the frequency converter.
Further, the phase difference between the phase of the user three-phase power supply and the phase of the output three-phase voltage of the frequency converter is within +/-5 degrees.
The invention provides an on-line switching system of screw compressor working frequency conversion by improvement, which operates according to the following mode;
firstly, a screw compressor receives a starting command;
secondly, the motor of the screw compressor is driven by the frequency converter 11 to start to operate;
thirdly, after the motor works to reach the rated rotating speed, the phase of the three-phase power supply of the user and the phase of the three-phase voltage output by the frequency converter 11 are monitored by the online switching module 12;
fourthly, after the phase difference between the two is within +/-5 degrees, the online switching module 12 controls the online switching unit 13 to cut off the output of the frequency converter 11 and switch on the power frequency input, so that the motor is driven by a power frequency power supply to complete the work frequency conversion online switching work of the screw compressor.
The invention provides a screw compressor work frequency conversion on-line switching system through improvement, which divides the starting and running modes of the screw compressor into two parts: the system comprises a variable frequency starting mode and a power frequency running mode, wherein the starting mode fully utilizes the characteristics of small variable frequency starting impact and low requirement on a user power supply; because the starting time is short, the influence on the harmonic wave of the power grid is greatly reduced, and the current is 1.2-1.5 times of the rated current when the frequency converter is started, the capacity of the frequency converter 11 can be reduced, the operation mode can be applied, the structure is simple, the price is substantial, simultaneously, the power consumption of the frequency converter is reduced by 2-3%, the harmonic wave of the power grid is eliminated, the frequency conversion of the starting mode is switched to the power frequency of the operation mode, and the requirements of flexibility and adaptability are met.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. The utility model provides an online switched systems of screw compressor worker frequency conversion which characterized in that: including converter (11), online switching module (12) and online switching unit (13), converter (11) are used for being responsible for helical-lobe compressor's frequency conversion and start, online switching module (12) are used for being responsible for the control calculation that helical-lobe compressor work frequency conversion switches on line, online switching unit (13) are used for being responsible for the implementation that helical-lobe compressor work frequency conversion switches on line.
2. The on-line switching system for the working frequency conversion of the screw compressor according to claim 1, wherein: and the frequency converter (11) is in control butt joint with a motor of the screw compressor.
3. The on-line switching system for the working frequency conversion of the screw compressor according to claim 1, wherein: the online switching module (12) specifically controls and calculates a switching time point for switching the variable frequency start to the power frequency operation.
4. The on-line switching system for the working frequency conversion of the screw compressor according to claim 1, wherein: the online switching unit (13) is specifically switched to power frequency operation by frequency conversion starting.
5. The on-line switching system for the working frequency conversion of the screw compressor according to claim 1, wherein: and the online switching module (12) is in control butt joint with the online switching unit (13).
6. The on-line switching system for the working frequency conversion of the screw compressor according to claim 1, wherein: and the online switching module (12) monitors the phase of a three-phase power supply of a user and the phase of three-phase voltage output by the frequency converter.
7. The on-line switching system for the working frequency conversion of the screw compressor according to claim 6, wherein: the phase difference between the phase of the user three-phase power supply and the phase of the three-phase voltage output by the frequency converter is within +/-5 degrees.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911056554.2A CN110953154A (en) | 2019-10-31 | 2019-10-31 | Screw compressor work frequency conversion online switching system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911056554.2A CN110953154A (en) | 2019-10-31 | 2019-10-31 | Screw compressor work frequency conversion online switching system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110953154A true CN110953154A (en) | 2020-04-03 |
Family
ID=69976063
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911056554.2A Pending CN110953154A (en) | 2019-10-31 | 2019-10-31 | Screw compressor work frequency conversion online switching system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110953154A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113550883A (en) * | 2021-07-19 | 2021-10-26 | 中国工商银行股份有限公司 | Water chilling unit, control method thereof, electronic equipment and storage medium |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201113439Y (en) * | 2007-06-19 | 2008-09-10 | 深圳市中传电气技术有限公司 | Large power frequency converter power frequency and variable frequency automatic switching device |
| CN101562353A (en) * | 2009-05-11 | 2009-10-21 | 山东新风光电子科技发展有限公司 | On-line mutual switching control device of fundamental frequency power supply and variable frequency power supply |
| CN105656389A (en) * | 2016-03-25 | 2016-06-08 | 无锡市优利康电气有限公司 | Power frequency and variable frequency switching method |
| CN109150061A (en) * | 2018-09-20 | 2019-01-04 | 山东奥卓电气科技发展有限公司 | A kind of heavy-duty motor work frequency conversion switching system and its control method |
| CN109245661A (en) * | 2018-09-29 | 2019-01-18 | 苏州英威腾电力电子有限公司 | Work frequency conversion switching circuit, control method, system, device and readable storage medium storing program for executing |
-
2019
- 2019-10-31 CN CN201911056554.2A patent/CN110953154A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201113439Y (en) * | 2007-06-19 | 2008-09-10 | 深圳市中传电气技术有限公司 | Large power frequency converter power frequency and variable frequency automatic switching device |
| CN101562353A (en) * | 2009-05-11 | 2009-10-21 | 山东新风光电子科技发展有限公司 | On-line mutual switching control device of fundamental frequency power supply and variable frequency power supply |
| CN105656389A (en) * | 2016-03-25 | 2016-06-08 | 无锡市优利康电气有限公司 | Power frequency and variable frequency switching method |
| CN109150061A (en) * | 2018-09-20 | 2019-01-04 | 山东奥卓电气科技发展有限公司 | A kind of heavy-duty motor work frequency conversion switching system and its control method |
| CN109245661A (en) * | 2018-09-29 | 2019-01-18 | 苏州英威腾电力电子有限公司 | Work frequency conversion switching circuit, control method, system, device and readable storage medium storing program for executing |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113550883A (en) * | 2021-07-19 | 2021-10-26 | 中国工商银行股份有限公司 | Water chilling unit, control method thereof, electronic equipment and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104734311A (en) | Compressor energy control circuit and method and centrifugal water chilling unit | |
| CN103475243A (en) | Control system and method for inverter | |
| CN110953154A (en) | Screw compressor work frequency conversion online switching system | |
| CN101527539B (en) | Speed adjustment control system of anti-inversion failure seamless switching motor and control method thereof | |
| Bhase et al. | Energy conservation using VFD | |
| CN102185557A (en) | Speed regulation control system of single-phase induction motor | |
| CN201690400U (en) | Frequency-conversion soft-start hybrid power cabinet | |
| CN101882905A (en) | Wireless remote soft start electrical cabinet | |
| CN107707158B (en) | Frequency converter comprehensive braking system and working method thereof | |
| CN103166543A (en) | Multi-split variable-frequency speed control system of energy-saving feedback type brushless coiling motor | |
| Thanyaphirak et al. | Soft starting control of single-phase induction motor using PWM AC Chopper control technique | |
| CN201947218U (en) | Single-phase induction motor speed regulation control system | |
| CN201328095Y (en) | Mineral flame-proof type variable-frequency high-voltage soft start device | |
| CN201674441U (en) | Motor soft starter with improved main circuit | |
| US11486614B2 (en) | Compressor and refrigeration device | |
| CN202612060U (en) | Air compressor | |
| CN109274300B (en) | Starting and excitation system and method for gas turbine generator set | |
| CN106992723B (en) | Brushless double-fed motor starting control device and method capable of realizing multi-mode operation | |
| CN205265469U (en) | Intelligence motor control means | |
| CN204851732U (en) | Aseptic wind system in dairy products workshop is start control system all | |
| CN204190662U (en) | Mine tailing sand pump governing system | |
| CN111884561B (en) | Crane goods smooth lifting control system and method based on doubly-fed motor | |
| CN210003460U (en) | of increase motor heat dissipation function drags two frequency conversion air compressor machine systems | |
| CN217563338U (en) | Flywheel energy storage system participating in power grid frequency modulation | |
| CN104410343A (en) | Excitation control method, excitation control system, controller and air conditioner external unit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200403 |