CN103311918A - Variable frequency oil engine-based direct current (DC) power generation system - Google Patents
Variable frequency oil engine-based direct current (DC) power generation system Download PDFInfo
- Publication number
- CN103311918A CN103311918A CN201310195485XA CN201310195485A CN103311918A CN 103311918 A CN103311918 A CN 103311918A CN 201310195485X A CN201310195485X A CN 201310195485XA CN 201310195485 A CN201310195485 A CN 201310195485A CN 103311918 A CN103311918 A CN 103311918A
- Authority
- CN
- China
- Prior art keywords
- oil machine
- frequency
- output
- frequency conversion
- variable frequency
- 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
- 238000010248 power generation Methods 0.000 title claims abstract description 13
- 238000006243 chemical reaction Methods 0.000 claims description 35
- 239000000446 fuel Substances 0.000 abstract description 4
- 239000003921 oil Substances 0.000 description 47
- 230000005284 excitation Effects 0.000 description 7
- 238000001514 detection method Methods 0.000 description 5
- 230000005611 electricity Effects 0.000 description 5
- 238000007599 discharging Methods 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 239000002253 acid Substances 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000009545 invasion Effects 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Landscapes
- Control Of Eletrric Generators (AREA)
Abstract
The invention relates to a variable frequency oil engine-based direct current (DC) power generation system which comprises a storage battery and a DC bus, wherein the storage battery is connected with the DC bus; the system also comprises a variable frequency oil engine, a medium frequency DC permanent magnet generator, a load detector and an oil engine variable frequency controller, wherein the variable frequency oil engine is connected with the medium frequency DC permanent magnet generator in a mechanical way; a DC output end of the medium frequency DC permanent magnet generator is connected with the DC bus; an input end of the load detector is connected with the DC bus; an output end of the load detector is connected with an input end of the oil engine variable frequency controller; and an output end of the oil engine variable frequency controller is connected with a control end of the variable frequency oil engine. The system can adjust the output voltage of the generator by adjusting the rotating speed of the variable frequency oil engine, and finally achieves the aim of adjusting the charge current and the load current of the storage battery. The oil engine works in a variable frequency state, rotates at high speed when having heavy load, and runs at low speed when having light load, thus greatly improving the system efficiency, improving the fuel consumption rate of the system, reducing the whole emission and achieving the aim of protecting the environment and saving energy.
Description
Technical field
The present invention relates to technical field of power generation, is a kind of DC power generation system based on the frequency conversion oil machine specifically.
Background technology
Because a lot of communication base stations are remote, without commercial power supply, thereby generally adopt diesel-electric set electric supply.The whole world comprises that the Middle East, north African, Southeast Asia and western China have about 500,000 base stations to adopt diesel-electric set electric supply at present.These greatest problem that adopt the diesel generating set of conventional art are that energy consumption and discharging are higher, do not meet the world trends of modern energy conservation and emission reduction.
The conventional diesel generator unit structure behind the fixed frequently oil machine band motor alternator output AC voltage, is transformed to the charging of 48V DC-voltage supply pond and load use through AC/DC power rectification module as shown in Figure 1.Because electric energy is through repeatedly conversion and oil machine constant speed work, electricity generation system efficient is low, cost is high, and system reliability is low.
Recently there is again the excitation-type dc low-voltage generator of scheme utilization output 48V that direct charging of batteries reached the effect that reduces system cost, but this scheme is still used traditional excitation-type generator, needs excitation winding to produce excitation field by exciting current.And exciting current need consume extra exciting power, and this has reduced the efficient of generator, and its generating efficiency generally is lower than 85%.In addition because traditional low frequency excitation generator is operated in power frequency 50Hz, thereby the volume of generator, weight are larger.And in this scheme, system is frequently work surely, and oil machine can't frequency control, thereby system's oil consumption is large, discharges high.
Summary of the invention
The purpose of this invention is to provide a kind of DC power generation system based on the frequency conversion oil machine, solving in the existing electricity generation system, oil machine can't variable frequency work and efficient is low, oil consumption large, discharging is high problem.
Realize that technical scheme of the present invention is as follows: a kind of DC power generation system based on the frequency conversion oil machine, comprise storage battery and dc bus, storage battery is connected to dc bus, also comprises frequency conversion oil machine, intermediate frequency dc permanent magnetic generator, load sensor and oil machine frequency-variable controller; The frequency conversion oil machine is mechanically connected to the intermediate frequency dc permanent magnetic generator, the dc output end of intermediate frequency dc permanent magnetic generator is connected to dc bus, the input of load sensor is connected to dc bus, the output of load sensor is connected to the input of oil machine frequency-variable controller, and the output of oil machine frequency-variable controller is connected to the control end of frequency conversion oil machine.
The intermediate frequency dc permanent magnetic generator comprises intermediate frequency permanent magnet generator and three-phase chopper circuit; The three-phase chopper circuit comprises the chopper circuit of three brachium pontis and direct current output cathode, direct current output negative pole, the chopper circuit of each brachium pontis is made of an ac input end and the first thyristor, the second thyristor, the anodic bonding of the first thyristor is to ac input end, the negative electrode of the second thyristor is connected to ac input end, the negative electrode of the first thyristor is connected to described direct current output cathode, and the anodic bonding of the second thyristor is to described direct current output negative pole; Three live wires (A, B, C) of described intermediate frequency permanent magnet generator are connected respectively to the ac input end (a, b, c) of three-phase chopper circuit, and the direct current output cathode of described three-phase chopper circuit, direct current output negative pole consist of the dc output end of described intermediate frequency dc permanent magnetic generator.
The oil machine frequency-variable controller comprises analog input module, single-chip microcomputer, analog output module and motor speed controller, and analog input module and analog output module are connected respectively to described single-chip microcomputer; The input of analog input module consists of the input of described oil machine frequency-variable controller, the output of analog output module is connected to the input of motor speed controller, and the output of motor speed controller consists of the output of described oil machine frequency-variable controller.
In the technical program, the frequency conversion oil machine refers at work petrol engine or the Diesel engine of variable speed.The rotating speed of frequency conversion oil machine and the pass of its frequency are: n=60f.In the following formula, n be engine rotating speed (rev/min), per minute 60 seconds, f are engine frequency (hertz).
The mode of operation of electricity generation system is as follows:
1, frequency conversion oil machine drives the intermediate frequency direct accumulators group of dc permanent magnetic generator output dc voltage and load supplying.
2, when load increases, according to the load characteristic of generator, its output voltage will descend.After load sensor detects this voltage drop, feed back this load condition oil feeder frequency-variable controller, control frequency conversion oil machine improves rotating speed, increases input power, with the raising generator output voltage, and provides larger charging current accumulators group.
3, when load reduces, based on identical principle, generator output voltage rises, load sensor feeds back this load condition oil feeder frequency-variable controller equally, control frequency conversion oil machine reduces rotating speed, reduces input power, reduces the direct current machine output voltage simultaneously, and reduce charging current.
4, frequency conversion oil machine is operated in minimum speed when zero load, full load works in maximum speed.
Native system comes the output voltage of regulator generator by the rotating speed of regulating the frequency conversion oil machine, and finally reaches the purpose of regulating battery charging electric current and load current.Because oil machine is operated in the frequency conversion state, i.e. high speed rotating during heavy duty, low cruise during underloading therefore can greatly improve system effectiveness, improves system's fuel consumption, reduces whole discharging, reaches the purpose of environment protecting and power-saving.Native system adopts 48V direct current intermediate frequency permanent magnet generator, and this intermediate frequency permanent magnet generator adopts the permanent magnet excitation material, does not need excitation winding, need not consume extra exciting power; Permanent magnet generator does not need the parts such as shaft coupling, bearing, axle, has reduced wearing and tearing and loss.Thereby the more traditional excitation generator of permanent magnet generator engine efficiency that uses in the native system is high by about 5%.Because generator is operated in about intermediate frequency 400Hz, more traditional 50Hz excitation electromotor frequency is high, thereby the generator volume is little, weight alleviates about 30% on year-on-year basis.Native system uses DC generator, cancelled the required AC/DC Switching Power Supply rectification module of traditional alternating current power-generating system, DC generator voltage is directly supplied with battery pack and load, improve system effectiveness, reduce system cost, eliminated more comprehensively the high-frequency noise that former Switching Power Supply rectification module brings simultaneously.Native system can be widely used in communication base station, military generator group and mobile pharos etc., and significantly reduce fuel oil consumption, exhaust emission and maintenance cost possess higher Social benefit and economic benefit.
Description of drawings
Fig. 1 is the structural representation that the frequency generator group is decided in traditional interchange.
Fig. 2 is the structural representation of DC frequency-changing electricity generation system.
Fig. 3 is the electrical schematic diagram of intermediate frequency mag-dynamo.
Fig. 4 is the structural representation of oil machine frequency-variable controller.
Fig. 5 is the output voltage characteristic curve of DC generator under load variations.
Fig. 6 is the output voltage characteristic curve of DC generator under rotation speed change.
Embodiment
As shown in Figure 2, frequency conversion oil machine is by bearing or terminal pad and intermediate frequency mag-dynamo mechanical connection; Driving generator by mechanical force after oil machine is rotated rotates; Thereby oil machine is converted into fuel kinetic energy and reaches generator.Generator produces electric current and voltage according to Faradic electricity magnetic induction principle cutting magnetic line in rotation, and its function is electric energy for transforming kinetic energy.The outlet terminal of generator and the both positive and negative polarity of batteries are electrically connected, to battery charging.The input signal of oil machine frequency-variable controller is the voltage detection signal of expression load voltage and load current.Detecting the load current method is: add Hall element at load end, Hall element can detect load current signal and induce the voltage signal of a transformation of scale, and this voltage signal feedback can be detected the load current size; The load voltage size then can be passed through the electric resistance partial pressure direct-detection.The output signal of oil machine frequency-variable controller is voltage signal, links to each other with the Throttle Opening Control of frequency conversion oil machine, changes the throttle size of frequency conversion oil machine by changing the output voltage signal size, with the amount of fuel that changes the frequency conversion oil machine what, thereby change the rotating speed of oil machine.
Such as Fig. 3, the intermediate frequency dc permanent magnetic generator comprises intermediate frequency permanent magnet generator and three-phase chopper circuit, but direct output of DC current is pressed.Usually the low-frequency voltage ripple that in DC generator, all contains 50Hz, the voltage ripple of this low frequency needs the energy storage devices such as jumbo electric capacity, or after connect the DC/DC Switching Power Supply and can eliminate.And the generator of this programme is operated in intermediate frequency 400Hz, thereby can greatly reduce voltage ripple, reduces the use of filter capacitor.The three-phase chopper circuit is usually operated under the all-pass state, is equivalent to three-phase bridge rectification circuit, does not produce any switch noise; Work as load dump, generator output voltage rises and when surpassing stop voltage, the ON time of every phase is dwindled in chopper circuit work, therefore can reduce rapidly output voltage to rated value.Batteries has the inhibitory action natural to the intermediate frequency voltage ripple, eliminates this voltage of intermediate frequency ripple, the direct voltage of output smoothing.While, the combination of employing DC generator and storage battery was conducive to the work of system because the pulsating voltage of lead-acid batteries intermediate frequency when charging and electric current are of value to the battery charge efficiency and improve battery life.
The oil machine frequency-variable controller as shown in Figure 4, its course of work is: behind the signals such as the smog that detects the sensor signal input, water enchroachment (invasion), battery temperature, ambient temperature, ambient humidity, can communicate by letter with the feed back on-site state with outer monitoring PC by RS485 bus or TCP/IP mouth.After the oil machine frequency-variable controller obtains load detection signal (generator voltage electric current, cell voltage current signal etc.) by load sensor, this detection signal input single-chip microcomputer is processed.Single-chip microcomputer thus load detection signal calculates the rotating speed that engine should move to the power curve of ratio engine, exports this tach signal to motor speed controller, regulates engine speed for it.For example: suppose frequency conversion oil machine rated output power 6KW when rotating speed is 1500rpm, rated output power 12KW under the 3000rpm.For the DC load of 48V, when load current was 100A, bearing power was 4.8KW, and supposing the system efficient is 80%, then needs the input power of 4.8KW/80%=6KW; When same load current was 200A, bearing power was 9.6KW, and supposing the system efficient is 80%, then needs the input power of 9.6KW/80%=12KW.Be 100A(48V when single-chip microcomputer detects load current) time, be at least 6KW by calculating the power output of finding engine this moment, the corresponding rotating speed of oil machine is 1500rpm, and just exporting relevant voltage signal notice oil machine frequency-variable controller is 1500rpm with the oil machine adjustment of rotational speed.Same increase to 200A(48V when load current) time single-chip microcomputer to calculate this moment required engine speed be 3000rpm, be 3000rpm therefore output relevant voltage signal is notified the oil machine frequency-variable controller with the oil machine adjustment of rotational speed.Wherein, motor speed controller selects Shanghai to permit an automatically controlled ESC9800 rotational speed governor.For guaranteeing necessary fuel-economizing, energy-saving effect, it is 20% to the slewing range that is fully loaded with rotating speed that engine no-load speed can be set, as shown in Figure 5; For this frequency conversion scope of coupling, by optimal design and the choose reasonable permanent magnetism magnetic material to generator, generator being set unloaded also is about 20% to fully loaded voltage drop, as shown in Figure 6 simultaneously.
Claims (6)
1. the DC power generation system based on the frequency conversion oil machine comprises storage battery and dc bus, and storage battery is connected to dc bus, it is characterized in that, also comprises frequency conversion oil machine, intermediate frequency dc permanent magnetic generator, load sensor and oil machine frequency-variable controller; The frequency conversion oil machine is mechanically connected to the intermediate frequency dc permanent magnetic generator, the dc output end of intermediate frequency dc permanent magnetic generator is connected to dc bus, the input of load sensor is connected to dc bus, the output of load sensor is connected to the input of oil machine frequency-variable controller, and the output of oil machine frequency-variable controller is connected to the control end of frequency conversion oil machine.
2. the DC power generation system based on the frequency conversion oil machine according to claim 1 is characterized in that, described intermediate frequency dc permanent magnetic generator comprises intermediate frequency permanent magnet generator and three-phase chopper circuit; The three-phase chopper circuit comprises the chopper circuit of three brachium pontis and direct current output cathode, direct current output negative pole, the chopper circuit of each brachium pontis is made of an ac input end and the first thyristor, the second thyristor, the anodic bonding of the first thyristor is to ac input end, the negative electrode of the second thyristor is connected to ac input end, the negative electrode of the first thyristor is connected to described direct current output cathode, and the anodic bonding of the second thyristor is to described direct current output negative pole; Three live wires (A, B, C) of described intermediate frequency permanent magnet generator are connected respectively to the ac input end (a, b, c) of three-phase chopper circuit, and the direct current output cathode of described three-phase chopper circuit, direct current output negative pole consist of the dc output end of described intermediate frequency dc permanent magnetic generator.
3. the DC power generation system based on the frequency conversion oil machine according to claim 1, it is characterized in that, described oil machine frequency-variable controller comprises analog input module, single-chip microcomputer, analog output module and motor speed controller, and analog input module and analog output module are connected respectively to described single-chip microcomputer; The input of analog input module consists of the input of described oil machine frequency-variable controller, the output of analog output module is connected to the input of motor speed controller, and the output of motor speed controller consists of the output of described oil machine frequency-variable controller.
4. the DC power generation system based on the frequency conversion oil machine according to claim 3 is characterized in that, the model of described motor speed controller is ESC9800.
5. according to claim 1 to 4 described any one DC power generation system based on the frequency conversion oil machine, it is characterized in that, described frequency conversion oil machine is the frequency conversion petrol engine.
6. according to claim 1 to 4 described any one DC power generation system based on the frequency conversion oil machine, it is characterized in that, described frequency conversion oil machine is the frequency conversion Diesel engine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310195485XA CN103311918A (en) | 2013-05-23 | 2013-05-23 | Variable frequency oil engine-based direct current (DC) power generation system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310195485XA CN103311918A (en) | 2013-05-23 | 2013-05-23 | Variable frequency oil engine-based direct current (DC) power generation system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103311918A true CN103311918A (en) | 2013-09-18 |
Family
ID=49136836
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310195485XA Pending CN103311918A (en) | 2013-05-23 | 2013-05-23 | Variable frequency oil engine-based direct current (DC) power generation system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103311918A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104682543A (en) * | 2015-03-17 | 2015-06-03 | 四川省辛普森动力设备有限公司 | Hybrid power supply system based on direct-current frequency variable power generator set |
| CN105897094A (en) * | 2015-02-18 | 2016-08-24 | 罗伯特·博世有限公司 | Generator-operated motor and operation of device consisting of active bridge rectifier |
| CN106685287A (en) * | 2015-11-10 | 2017-05-17 | 卡特彼勒公司 | Smart load bank and excitation control |
| CN106803670A (en) * | 2017-02-15 | 2017-06-06 | 武汉理工大学 | The wind-solar-diesel storage direct-current micro-grid Battery charge controller system and method for low cost |
| CN109391194A (en) * | 2018-11-07 | 2019-02-26 | 郑州佛光发电设备有限公司 | A kind of the pressure stabilizing control method and system of DC permanent magnetic generator group |
| CN113300534A (en) * | 2021-05-18 | 2021-08-24 | 杨立 | Intelligent energy-saving motor with variable frequency output |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101093941A (en) * | 2007-06-07 | 2007-12-26 | 何培祥 | Permanent magnet numeral power set with multiple oil engines |
| US20090072772A1 (en) * | 2006-03-07 | 2009-03-19 | Siemens Aktiengesellschaft | Diesel-electric drive system having a synchronous generator with permanent magnet excitation |
| CN102510255A (en) * | 2011-11-04 | 2012-06-20 | 上海科泰电源股份有限公司 | Frequency-conversion energy-saving diesel generator set of communication base station |
| CN102738934A (en) * | 2012-07-09 | 2012-10-17 | 福建亚南电机有限公司 | External-rotor intermediate-frequency permanent magnet generator device |
| CN203312805U (en) * | 2013-05-23 | 2013-11-27 | 成都乾威科技有限公司 | Direct-current power generation system based on frequency-variable oil machine |
-
2013
- 2013-05-23 CN CN201310195485XA patent/CN103311918A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20090072772A1 (en) * | 2006-03-07 | 2009-03-19 | Siemens Aktiengesellschaft | Diesel-electric drive system having a synchronous generator with permanent magnet excitation |
| CN101093941A (en) * | 2007-06-07 | 2007-12-26 | 何培祥 | Permanent magnet numeral power set with multiple oil engines |
| CN102510255A (en) * | 2011-11-04 | 2012-06-20 | 上海科泰电源股份有限公司 | Frequency-conversion energy-saving diesel generator set of communication base station |
| CN102738934A (en) * | 2012-07-09 | 2012-10-17 | 福建亚南电机有限公司 | External-rotor intermediate-frequency permanent magnet generator device |
| CN203312805U (en) * | 2013-05-23 | 2013-11-27 | 成都乾威科技有限公司 | Direct-current power generation system based on frequency-variable oil machine |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105897094A (en) * | 2015-02-18 | 2016-08-24 | 罗伯特·博世有限公司 | Generator-operated motor and operation of device consisting of active bridge rectifier |
| CN104682543A (en) * | 2015-03-17 | 2015-06-03 | 四川省辛普森动力设备有限公司 | Hybrid power supply system based on direct-current frequency variable power generator set |
| CN104682543B (en) * | 2015-03-17 | 2019-05-07 | 四川省辛普森动力设备有限公司 | A kind of mixed power supply system based on DC frequency-changing generating set |
| CN106685287A (en) * | 2015-11-10 | 2017-05-17 | 卡特彼勒公司 | Smart load bank and excitation control |
| CN106685287B (en) * | 2015-11-10 | 2021-09-17 | 卡特彼勒公司 | Intelligent load group and excitation control |
| CN106803670A (en) * | 2017-02-15 | 2017-06-06 | 武汉理工大学 | The wind-solar-diesel storage direct-current micro-grid Battery charge controller system and method for low cost |
| CN106803670B (en) * | 2017-02-15 | 2019-07-23 | 武汉理工大学 | The wind-solar-diesel storage direct-current micro-grid battery charge controller system and method for low cost |
| CN109391194A (en) * | 2018-11-07 | 2019-02-26 | 郑州佛光发电设备有限公司 | A kind of the pressure stabilizing control method and system of DC permanent magnetic generator group |
| CN113300534A (en) * | 2021-05-18 | 2021-08-24 | 杨立 | Intelligent energy-saving motor with variable frequency output |
| CN113300534B (en) * | 2021-05-18 | 2022-07-22 | 江苏锡安达防爆股份有限公司 | Intelligent energy-saving motor with variable frequency output |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204928358U (en) | Diesel generator economizer system of intermittent type nature operation continuation power supply | |
| CN101814763B (en) | Small wind power generation conversion device | |
| CN103311918A (en) | Variable frequency oil engine-based direct current (DC) power generation system | |
| WO2018133511A1 (en) | Hybrid-powered unmanned vehicle | |
| WO2010108342A1 (en) | Excitation control system for marine diesel brushless doubly fed shaft generator and control method thereof | |
| CN202889279U (en) | Brushless doubly fed motor excitation control device | |
| CN103457313B (en) | Wind and solar general type new energy intelligent control system and method | |
| CN104467583B (en) | Permanent DC bus-bar voltage permanent magnet generator unit based on prime mover speed governing | |
| WO2010066107A1 (en) | Hybrid ac power supply control system for communication base station | |
| CN203312805U (en) | Direct-current power generation system based on frequency-variable oil machine | |
| CN202737555U (en) | Composite energy device for ships and ship equipped with composite energy device | |
| CN101604865B (en) | Wind power generation system for low-voltage DC power supply | |
| CN211377693U (en) | Power transmission line hybrid power supply based on solar energy and induction energy obtaining | |
| CN204068408U (en) | A new type of power supply device for electric cable well drainage | |
| CN203057040U (en) | Discrete frequency-conversion soft starting device with no speed sensor | |
| CN104539023B (en) | Wind power generation and power supply system based on grid power complementation | |
| CN201708564U (en) | Off-network type wind and light-combined generating system based on optimum generated energy matching | |
| CN103956948B (en) | Intelligent AC speed changing diesel generator group | |
| CN203707864U (en) | Novel hybrid-energy 48V direct-current frequency-conversion power generation system | |
| CN102810902A (en) | Household hybrid power supply management system and power supply management method | |
| CN102223136A (en) | Non-energy-storing motor-driven system for complementary power supply of wind power generation and electrical network | |
| CN202094668U (en) | Intelligent charging device of fire emergency power supply | |
| CN103259312A (en) | Novel wind and photovoltaic complementary power generation system | |
| CN204349695U (en) | Multifunctional generating unit | |
| CN202940597U (en) | Variable-speed variable-frequency energy-saving power generation and distribution device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C05 | Deemed withdrawal (patent law before 1993) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20130918 |