CN110557030A - Design method of cascaded high-voltage frequency converter for high-altitude area - Google Patents
Design method of cascaded high-voltage frequency converter for high-altitude area Download PDFInfo
- Publication number
- CN110557030A CN110557030A CN201810536808.XA CN201810536808A CN110557030A CN 110557030 A CN110557030 A CN 110557030A CN 201810536808 A CN201810536808 A CN 201810536808A CN 110557030 A CN110557030 A CN 110557030A
- Authority
- CN
- China
- Prior art keywords
- voltage
- frequency converter
- altitude
- low
- rated
- 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
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
Abstract
the invention discloses a design method of a cascade high-voltage frequency converter for a high-altitude area, which comprises the following steps: 1) reinforcing external insulation; 1.1) adopting a mode of enlarging air gap and creepage distance; 1.2) the rated voltage of the low-voltage electrical appliance of the high-voltage frequency converter is at least one grade higher than the actual circuit voltage when the model is selected; 1.3) selecting a product with rated voltage at least one grade higher than the actual circuit voltage or using a high-model product by a high-voltage electrical appliance of the high-voltage frequency converter during model selection; 2) the lightning arrester in the high-voltage frequency converter adopts a high-altitude lightning arrester, and corrects the internal power frequency discharge value and the protection value; 3) the rated voltage value of an air switch or a contactor adopted in a low-voltage loop of the high-voltage frequency converter is greater than the working voltage grade of the low-voltage loop; 4) and adopting a capacity reduction use method for a phase-shifting transformer, a power unit module and a switching power supply in the high-voltage frequency converter. The design method has the advantages of improving the high-altitude environment adaptability of the high-voltage frequency converter, reducing the workload and the like.
Description
Technical Field
The invention mainly relates to the technical field of frequency conversion, in particular to a design method of a cascade high-voltage frequency converter for a high-altitude area.
background
The variable frequency speed regulation is an important energy-saving ring for an electric towing system in the industrial field at present, and the high-power fan and the water pump adopt a variable frequency speed regulation operation scheme to reduce the energy consumption by more than 30 percent. At present, the cascade high-voltage frequency converter has a market mainstream position in the domestic high-voltage frequency conversion speed regulation market by virtue of the advantages of low harmonic content, high power factor, capability of directly driving a common high-voltage motor and the like.
according to JB/T7573-94 general technical conditions of electronic products under plateau environmental conditions, plateaus have severe natural climate conditions, wherein the conditions which have great influence on indoor electrical equipment include:
(1) air pressure or air density is low;
(2) The absolute humidity of the air is small.
The main influence of the plateau environment on the frequency converter and parts thereof is as follows:
(1) a decrease in external insulation strength;
(2) Partial discharge voltage is reduced, corona initial voltage is reduced, and corona corrosion is serious;
(3) The arc extinguishing performance of low-voltage electrical appliances such as an air switch, a relay and a contactor is reduced;
(4) the heat dissipation capacity is reduced, and the temperature rise is increased;
(5) The change of physical and chemical properties of electrical insulating materials, the volatilization of plasticizers in plastic products is accelerated, and sealed containers expand, deform and are easy to damage.
china is high in terrain, west and east, but the standard of domestic and foreign high-voltage electrical equipment generally stipulates that the altitude of the product is 1000m or less, and the application requirements of high altitude areas such as Qinghai-Tibet, inner Mongolia and northwest cannot be met. The common cascade high-voltage frequency conversion equipment is designed according to the standard of 1000m below the altitude. When the altitude rises, the air density is reduced, so that the problems of reduced external insulation strength, reduced partial discharge voltage, reduced arc extinguishing performance, reduced heat dissipation capacity, changed physical and chemical properties of the insulating material and the like are caused, and the running safety of equipment is threatened.
disclosure of Invention
The technical problem to be solved by the invention is as follows: aiming at the technical problems in the prior art, the invention provides a design method of a cascaded high-voltage frequency converter for a high-altitude area, which improves the high-altitude environment adaptability of the high-voltage frequency converter and has less design workload.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
a design method of a cascade high-voltage frequency converter used in a high altitude area is designed from one or more aspects to make the high-voltage frequency converter suitable for a high altitude environment; the method comprises the following steps:
1) Reinforcing external insulation;
1.1) adopting a mode of enlarging air gap and creepage distance to strengthen external insulation;
1.2) selecting a product with rated voltage higher than actual circuit voltage by at least one grade when a low-voltage electrical appliance of the high-voltage frequency converter is in type selection so as to ensure the insulation strength;
1.3) selecting a product with rated voltage higher than the actual circuit voltage by at least one grade or using a plateau type product to ensure the insulation strength when a high-voltage electrical appliance of the high-voltage frequency converter selects the type;
2) The lightning arrester in the high-voltage frequency converter adopts a high-altitude lightning arrester, and the internal power frequency discharge value and the protection value of the high-altitude lightning arrester are corrected so as to be suitable for a high-altitude environment;
3) the rated voltage value of an air switch or a contactor adopted in a low-voltage loop of the high-voltage frequency converter is greater than the working voltage grade of the low-voltage loop, so that the high-voltage frequency converter can be reliably disconnected in a high-altitude environment;
4) A capacity reduction using method is adopted for a phase-shifting transformer, a power unit module and a switching power supply in a high-voltage frequency converter so as to ensure normal heat dissipation and temperature rise.
As a further improvement of the above technical solution:
in 1.1), when the altitude is 1000-4000 m, the required electric gaps are respectively as follows:
The voltage of the high-voltage circuit is 10kV, and the actual value of the electric gap is more than or equal to 182.4 mm;
The circuit voltage of the intermediate link is less than or equal to 1000V, and the actual value of the electrical gap is more than or equal to 10.8 mm;
The voltage of the low-voltage distribution circuit is less than or equal to 380V, and the actual value of the electric gap is more than or equal to 4.05 mm.
in 1.2), the low-voltage appliances include air switches, relays, contactors, buttons, indicator lights, wiring terminals and electrical connectors, all using models rated at 690VAC or 660VAC, with the actual operating voltage being 220VAC or 380VAC or 24 VDC.
In 1.2), the low-voltage control transformer is made of solid insulating materials, whether the insulation and voltage resistance performance of the low-voltage control transformer meets the requirements or not is mainly determined by the distance between an outgoing line and a wiring terminal of the low-voltage control transformer, the distance when a 220V transformer is selected is not less than 8mm, and the distance when a 690V transformer is selected is not less than 12 mm.
In 1.2), the switching power supply, the circuit board, the controller and the touch screen have large corresponding external insulation allowance due to extremely low internal voltage level, so that the requirement of high-altitude environment is met.
In the step 1.3), the rated direct current voltage of the power unit module is reduced by reducing the rated voltage of the secondary winding of the phase-shifting transformer in the high-voltage frequency converter, and meanwhile, the rated output voltage is kept by increasing the cascade number of the modules, so that the insulation performance allowance of the modules is improved.
In step 1.3), the relative earth spacing of the flat insulator is lifted by adding the insulating piece cushion blocks so as to improve the external insulation level.
In the step 1.3), the distances among the diodes, the IGBTs and the wiring terminals of the support capacitor in the power module in the high-voltage frequency converter are all larger than 12mm, and the requirement of the DC800V circuit on the electric clearance at the altitude of 4000m is met.
in 4), the capacity of the phase-shifting transformer and the power unit module is reduced by 0.5% per 100m at an altitude of more than 1000m, and the capacity is reduced by 15% at 4000 m.
in 4), the type selection margin of the switching power supply and the control transformer needs to exceed 50%.
compared with the prior art, the invention has the advantages that:
The design method of the cascade high-voltage frequency converter for the high-altitude area strengthens external insulation from the aspects of increasing air gap and creepage distance, electric appliance voltage grade, type selection and the like, and considers temperature rise heat dissipation by adopting a capacity reduction method, so that the design method is suitable for the high-altitude area environment, does not need to customize each part, can select standard products with rich supply on the market, meets the requirement of plateau application according to the designed products, has better inheritance to the universal cascade frequency converter, effectively reduces the workload of design and development, and reduces the difficulty of purchasing, manufacturing and maintenance.
Drawings
Fig. 1 is a topology structure diagram of a frequency converter in the present invention.
Fig. 2 is a circuit diagram of a power unit according to the present invention.
FIG. 3 is a schematic diagram of the output voltage of the power unit according to the present invention.
FIG. 4 is a diagram of the output voltage waveform of the high voltage inverter according to the present invention.
Detailed Description
The invention is further described below with reference to the figures and the specific embodiments of the description.
As shown in fig. 1 to 3, the method for designing a cascaded high-voltage inverter for a high-altitude area according to the present embodiment is designed from one or more of the following aspects, so that the high-voltage inverter is suitable for a high-altitude environment (1000 m to 4000 m); the method comprises the following steps:
1) Reinforcing external insulation;
1.1) adopting a mode of enlarging air gap and creepage distance to strengthen external insulation;
1.2) selecting a product with rated voltage higher than actual circuit voltage by at least one grade when a low-voltage electrical appliance of the high-voltage frequency converter is in type selection so as to ensure the insulation strength;
1.3) selecting a product with rated voltage higher than the actual circuit voltage by at least one grade or using a plateau type product to ensure the insulation strength when a high-voltage electrical appliance of the high-voltage frequency converter selects the type;
2) The lightning arrester in the high-voltage frequency converter adopts a high-altitude lightning arrester, and the internal power frequency discharge value and the protection value of the high-altitude lightning arrester are corrected so as to be suitable for a high-altitude environment;
3) The rated voltage value of an air switch or a contactor adopted in a low-voltage loop of the high-voltage frequency converter is greater than the working voltage grade of the low-voltage loop, so that the high-voltage frequency converter can be reliably disconnected in a high-altitude environment;
4) A capacity reduction using method is adopted for a phase-shifting transformer, a power unit module and a switching power supply in a high-voltage frequency converter so as to ensure normal heat dissipation and temperature rise.
The design method of the cascade high-voltage frequency converter for the high-altitude area strengthens external insulation from the aspects of increasing air gap and creepage distance, electric appliance voltage grade, type selection and the like, and considers temperature rise heat dissipation by adopting a capacity reduction method, so that the design method is suitable for the high-altitude area environment, does not need to customize each part, can select standard products with rich supply on the market, meets the requirement of plateau application according to the designed products, has better inheritance to the universal cascade frequency converter, effectively reduces the workload of design and development, and reduces the difficulty of purchasing, manufacturing and maintenance.
The process of the invention is further illustrated below with reference to a specific embodiment:
For a conventional cascade frequency converter device, which comprises main parts such as a power unit, a phase-shifting transformer, a controller and a bypass cabinet, and auxiliary parts such as a ventilation heating lighting device, high altitude adaptive adjustment is mainly performed from the following four aspects:
1) External insulation
the main methods for strengthening the external insulation include:
1.1, enlarging air gap and creepage distance;
Adopt the mode of increaseing air gap and creep distance to strengthen external insulation, when the height above sea level 4000m, the electric clearance that needs is respectively as follows:
The voltage of the high-voltage circuit is 10kV, and the actual value of the electric gap is more than or equal to 182.4 mm;
The circuit voltage of the middle link is less than or equal to 1000V, and the actual value of the electric gap is more than or equal to 10.8 mm;
The voltage of the low-voltage distribution circuit is less than or equal to 380V, and the electrical clearance is more than or equal to 4.05 mm;
if the creepage distance determined according to table 10 of GB 12668.501-2013 is smaller than the electrical clearance corrected by the above method, the creepage distance should be increased to the electrical clearance.
The whole structure is redesigned by adopting a method of enlarging air gap and creep distance.
and 1.2, selecting a voltage level of a first gear.
And the low-voltage electrical appliance selects a product with rated voltage at least one grade higher than the actual circuit voltage during model selection so as to ensure the insulation strength.
the low-voltage electrical appliances such as common air switches, relays, contactors, buttons, indicator lamps, wiring terminals and electric connectors in the market all use the model of rated voltage 690VAC or 660VAC, the actual working voltage is 220VAC/380VAC/24VDC, and the external insulation can meet the use requirement of high-altitude environment;
the low-voltage control transformer is generally made of solid insulating materials, whether the insulating and voltage-resisting performance of the low-voltage control transformer meets the plateau requirements or not is mainly determined by the distance between a leading-out wire and a connecting terminal of the low-voltage control transformer, the distance between the selected 220V transformers is more than or equal to 8mm, and the distance between the selected 690V transformers is more than or equal to 12 mm.
The low-voltage integrated components such as the switching power supply, the circuit board, the controller, the touch screen and the like are generally large in corresponding external insulation allowance due to extremely low internal voltage level, and special consideration is not needed.
high-voltage parts (high-voltage contactors, insulators, voltage measuring elements and the like) use high-model products or select a first-gear higher voltage level.
1.3, using a high prototype product;
High-voltage contactor chooses plateau type product for use, and it has done special treatment in three aspects:
The creepage distance is specially processed, and the phase distance of the vacuum tubes is larger than 10 kV; the size is larger than that of the non-plateau type;
considering the use of high altitude capacity reduction, the electrified current of the vacuum tube is enlarged by 20 percent of allowance compared with a common 630A contactor;
The insulating frame of the contactor is specially treated.
the insulator selects a plateau product, special treatment is carried out on the aspects of phase spacing, creepage and insulation, the external insulation level is improved, or the relative ground spacing is improved by increasing the cushion blocks of the insulating parts and the like so as to use a common flat prototype product.
The voltage measuring element uses a voltage dividing circuit board to perform voltage dividing sampling, the phase and relative ground clearance of the circuit board meet the requirement of 4000m altitude, and if a voltage transformer is adopted, a plateau product also needs to be customized.
The phase-shifting transformer is adjusted by the supplier.
the cable insulation performance does not depend on air insulation, and special consideration is not needed.
The main power electronic devices in the power module comprise diodes, IGBTs and wiring terminals of a support capacitor, the distance between the wiring terminals is larger than 12mm, and the requirement of a DC800V circuit on an electric gap at the altitude of 4000m is met.
When the internal bus, the copper bar and the like are designed, attention needs to be paid to correspondingly increasing gaps or adopting an insulating material to wrap and fill to strengthen insulation.
The rated direct current voltage of a power unit module is reduced to 800VDC by reducing the rated voltage of a secondary winding of the phase-shifting transformer, and meanwhile, the rated output voltage of the device is kept by increasing the number of module cascade connection to 9 cascade connection, so that the allowance of the insulating property of the module is improved.
Of course, the external insulation strength can also be enhanced by additionally arranging an insulating protective plate, an insulating cushion block, an insulating material wrapping mode, a casting mode and the like.
2) partial discharge and corona
The high-altitude low-air pressure reduces the air pressure in the inner cavity of the lightning arrester, so that the power frequency discharge voltage is reduced, and therefore the high-altitude lightning arrester is selected and used, and the power frequency discharge value and the protection value in the high-altitude lightning arrester are corrected.
The high-altitude phase-shifting transformer is adopted to enhance the corona resistance of the insulating material.
For high-voltage electrical equipment, sharp corners, abrupt changes in cross section and the like of metal parts are avoided in design, and the corona resistance of the insulating material is enhanced.
3) Air arc extinguishing performance
The working voltage grade of the low-voltage loop of the frequency converter is 220VAC/380VAC/24VDC, the selected air-on rated voltage value is 690VAC, the rated breaking capacity of the low-voltage loop reaches 6kA to 10kA, and the low-voltage loop is much higher than the short-circuit current of the low-voltage loop, so that the low-voltage loop can be reliably broken in a plateau environment.
The intermediate relay in the frequency converter is generally used for isolating switching value signals, is not used for breaking operation of loads, and does not need to consider breaking capacity of the intermediate relay.
The contactor used in the low-voltage loop in the frequency converter is selected with a model with a larger current grade to obtain enhanced breaking capacity and ensure reliable breaking, and meanwhile, the model is properly selected according to the electric service life curve of the contactor to ensure that the electric service life of the contactor meets the requirement of the whole life cycle of the device.
4) heat dissipation and temperature rise
A reduction in air pressure or air density causes a reduction in the cooling effect of the air medium. For electrical products that use natural convection, forced air, or air radiators as the primary heat dissipation means, the temperature rise increases due to the reduction in heat dissipation capacity. Within the range of the altitude of 5000m, the elevation per liter is 1000m, namely, every time the average air pressure is reduced by 7.7-10.5 kPa, the temperature rise is increased by 3% -10%.
a) the rising rate of the temperature rise of static electric appliances along with the elevation rise is generally within 0.4K per 100m, but for high-heating electric appliances such as electric furnaces, resistors, electric welding machines and other electric appliances, the rising rate of the temperature rise along with the elevation rise reaches more than 2K per 100 m.
b) the temperature rise of the dry forced air-cooled power transformer is 1.0 percent of the rated temperature rise of the dry forced air-cooled power transformer per 100m along with the increase rate of the altitude.
for the frequency converter system, high-loss components (phase-shifting transformer and power unit module) are mainly considered. The volume reduction method is adopted, the volume reduction is about 0.5% per 100m above 1000m, and the volume reduction is required to be 15% at the altitude of 4000 m.
The low-voltage heat sources such as the switching power supply and the like are used by 15 percent of capacity reduction, and the model selection allowance of low-voltage power supply equipment such as a common switching power supply, a control transformer and the like exceeds 50 percent.
The high-altitude temperature rise increasing rate of the natural cooling type current-carrying parts such as cables, copper bars and the like is lower than that of high-altitude heating electric appliances such as transformers and the like, and the capacity of the current-carrying parts is reduced along with the whole machine to obtain a margin.
As shown in fig. 1 to fig. 3, the cascade-type frequency converter uses a plurality of independent low-voltage power units connected in series to realize high-voltage output, and includes two major parts, namely a phase-shifting transformer and a power unit. The transformer transformation ratio is adjusted to adapt to different network voltages, and the maximum output voltage of the device is changed by adjusting the serial number of the power units. Fig. 1 is a topology structure diagram of a 6-cascade frequency converter.
The phase-shifting transformer adopts multiple design, high voltage of a network side is converted into a plurality of groups of low voltage of a secondary side, windings of the secondary side are connected in an edge-extending triangular mode during winding, a fixed phase difference is formed between the windings, a multi-pulse rectification mode is generated, harmonic currents of the windings (input of a power unit) of the secondary side of the transformer are mutually offset and are not reflected to the high voltage side, therefore, the current waveform of a power grid is effectively improved, and the harmonic pollution of a frequency converter to the power grid is basically eliminated.
the secondary windings of the transformer are independent of each other and individually supply power to one power unit, so that the main loop of each power unit is opposite and operates in a low-voltage state. The relative voltage between each power unit is born by the insulation of the secondary winding of the transformer, and the problem of series voltage sharing does not exist between the power units.
The power unit is a basic unit for realizing voltage and frequency conversion output by the high-voltage frequency converter, the voltage and frequency conversion function of the whole frequency converter is realized by a single power unit, and each power unit is equivalent to an AC-DC-AC voltage single-phase low-voltage frequency converter.
The typical power unit topology type is an H-bridge two-level power unit, the rectification side uses a diode three-phase full-bridge uncontrollable full-wave rectification, the middle part adopts high-capacity capacitance filtering and energy storage, the output side is an H-bridge formed by 4 IGBTs, and single-phase constant-amplitude alternating current PWM waveform output voltage is provided. The circuit structure of the power unit is shown in figure 2.
Take a 6kV6 cascade frequency converter as an example: the output rated voltage of the single power unit is 580V. Each phase is connected in series by 6 same power units to obtain 3480V single-phase voltage, and the corresponding line voltage of the three-phase star connection is 6000V. The three phases have 18 power units, and the connection diagram is shown in fig. 3.
the total output voltage of the inverter is obtained by serially superimposing the output voltages of the power cells, and although each cell outputs a constant-amplitude PWM voltage waveform, the cell outputs have a certain phase shift from each other, and after serially superimposing the cell outputs, a sinusoidal stepped PWM waveform is obtained on the output side of the inverter, as shown in fig. 4.
although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present invention, or modify equivalent embodiments to equivalent variations, without departing from the scope of the invention, using the teachings disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention should fall within the protection scope of the technical scheme of the present invention, unless the technical spirit of the present invention departs from the content of the technical scheme of the present invention.
Claims (10)
1. A design method of a cascade high-voltage frequency converter used in a high altitude area is characterized in that the design is carried out from one or more aspects, so that the high-voltage frequency converter is suitable for a high altitude environment; the method comprises the following steps:
1) reinforcing external insulation;
1.1) adopting a mode of enlarging air gap and creepage distance to strengthen external insulation;
1.2) selecting a product with rated voltage higher than actual circuit voltage by at least one grade when a low-voltage electrical appliance of the high-voltage frequency converter is in type selection so as to ensure the insulation strength;
1.3) selecting a product with rated voltage higher than the actual circuit voltage by at least one grade or using a plateau type product to ensure the insulation strength when a high-voltage electrical appliance of the high-voltage frequency converter selects the type;
2) The lightning arrester in the high-voltage frequency converter adopts a high-altitude lightning arrester, and the internal power frequency discharge value and the protection value of the high-altitude lightning arrester are corrected so as to be suitable for a high-altitude environment;
3) The rated voltage value of an air switch or a contactor adopted in a low-voltage loop of the high-voltage frequency converter is greater than the working voltage grade of the low-voltage loop, so that the high-voltage frequency converter can be reliably disconnected in a high-altitude environment;
4) A capacity reduction using method is adopted for a phase-shifting transformer, a power unit module and a switching power supply in a high-voltage frequency converter so as to ensure normal heat dissipation and temperature rise.
2. The method as claimed in claim 1, wherein in 1.1), when the altitude is 1000-4000 m, the required electrical gaps are as follows:
The voltage of the high-voltage circuit is 10kV, and the actual value of the electric gap is more than or equal to 182.4 mm;
The circuit voltage of the intermediate link is less than or equal to 1000V, and the actual value of the electrical gap is more than or equal to 10.8 mm;
The voltage of the low-voltage distribution circuit is less than or equal to 380V, and the actual value of the electric gap is more than or equal to 4.05 mm.
3. The method as claimed in claim 1, wherein in 1.2), the low voltage electric appliances include air switches, relays, contactors, buttons, indicator lamps, connection terminals and electric connectors, each using a model with a rated voltage of 690VAC or 660VAC, wherein the actual operating voltage is 220VAC or 380VAC or 24 VDC.
4. The method as claimed in claim 1, wherein in 1.2), the low voltage control transformer is made of solid insulating material, and whether the voltage insulation and withstand voltage performance of the low voltage control transformer meets the requirements is mainly determined by the distance between the outgoing line and the connection terminal, the distance when a 220V transformer is selected is not less than 8mm, and the distance when a 690V transformer is selected is not less than 12 mm.
5. the method as claimed in claim 1, wherein in 1.2), the switching power supply, the circuit board, the controller and the touch screen have a large external insulation margin due to their low internal voltage levels, thereby meeting the high altitude environment requirements.
6. the method as claimed in any one of claims 1 to 5, wherein in step 1.3), the rated dc voltage of the power unit module is reduced by reducing the rated voltage of the secondary winding of the phase-shifting transformer in the high-voltage inverter, and the rated output voltage is maintained by increasing the number of module cascades, so as to improve the margin of the module insulation performance.
7. The method as claimed in any one of claims 1 to 5, wherein in step 1.3), the external insulation level is increased by increasing the ground-to-ground distance of the flat type insulator by means of the additional insulation spacers.
8. the method as claimed in any one of claims 1 to 5, wherein in step 1.3), the distances between the diode, the IGBT and the connection terminal of the support capacitor inside the power module in the high-voltage inverter are all greater than 12mm, so as to meet the requirement of the DC800V circuit on the electrical clearance at 4000m altitude.
9. The method as claimed in any one of claims 1 to 5, wherein in 4), the phase-shifting transformer and the power unit module have a capacity reduction of 0.5% per 100m at an altitude above 1000m, and have a capacity reduction of 15% at 4000 m.
10. The method as claimed in any one of claims 1 to 5, wherein in 4), the type selection margin of the switching power supply and the control transformer is more than 50%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810536808.XA CN110557030A (en) | 2018-05-30 | 2018-05-30 | Design method of cascaded high-voltage frequency converter for high-altitude area |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810536808.XA CN110557030A (en) | 2018-05-30 | 2018-05-30 | Design method of cascaded high-voltage frequency converter for high-altitude area |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110557030A true CN110557030A (en) | 2019-12-10 |
Family
ID=68735228
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810536808.XA Pending CN110557030A (en) | 2018-05-30 | 2018-05-30 | Design method of cascaded high-voltage frequency converter for high-altitude area |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110557030A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113847010A (en) * | 2021-10-20 | 2021-12-28 | 天水电气传动研究所集团有限公司 | Autonomous capacity reduction control system and method for main transmission device of petroleum electric drill |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104821727A (en) * | 2015-04-24 | 2015-08-05 | 深圳市禾望电气股份有限公司 | Switch power supply suitable for high-overvoltage-grade high-altitude place |
-
2018
- 2018-05-30 CN CN201810536808.XA patent/CN110557030A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104821727A (en) * | 2015-04-24 | 2015-08-05 | 深圳市禾望电气股份有限公司 | Switch power supply suitable for high-overvoltage-grade high-altitude place |
Non-Patent Citations (4)
| Title |
|---|
| 余晓光: "高海拔地区电气设计探讨", 《现代建筑电气》 * |
| 田冰冰: "高原地区的电气设备影响及选择", 《中国设备工程》 * |
| 罗志辉: "高原环境对电气设备的影响及设计方案", 《电子测试》 * |
| 陈开运: "高海拔电气设备工作特点及设计要求", 《机车电传动》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113847010A (en) * | 2021-10-20 | 2021-12-28 | 天水电气传动研究所集团有限公司 | Autonomous capacity reduction control system and method for main transmission device of petroleum electric drill |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9093923B2 (en) | Three-level converter having phase bridge arm | |
| CN213212719U (en) | Novel 690V variable frequency motor power supply system | |
| CN110557030A (en) | Design method of cascaded high-voltage frequency converter for high-altitude area | |
| CN111600467B (en) | System operation method for improving stability of energy router | |
| CN205017229U (en) | Electric energy repayment type electronic load dc -to -ac converter | |
| CN210898542U (en) | Filtering reactive power compensation device | |
| CN113037101B (en) | High-frequency matrix type light-weight totally-enclosed high-voltage frequency conversion device | |
| CN107171270B (en) | Intensive deicing device constant current, constant pressure modularization dynamic passive compensation component | |
| CN106159975B (en) | Series compensation device suitable for multi-circuit line | |
| CN212343332U (en) | Low-voltage switch cabinet | |
| CN210074787U (en) | High-power converter circuit topological structure for offshore wind power | |
| CN215870891U (en) | High-voltage intelligent power saving device | |
| CN202679284U (en) | Intelligent electronic starting cabinet | |
| CN203387058U (en) | Low-voltage reactive power compensation cabinet | |
| CN110086248A (en) | One kind being used for grid type power plant auxiliary system | |
| CN218526098U (en) | Special passive filtering compensation device for rolling mill | |
| CN112072958A (en) | Soft start system | |
| CN215681474U (en) | High-voltage switch equipment | |
| CN216751311U (en) | GIS voltage reduction integrated system for thermal power plant | |
| CN201821006U (en) | Heavy-current high-speed on/off controller | |
| CN219576648U (en) | Power supply and distribution system | |
| CN218603395U (en) | High-voltage reactance soft starting device with reactive compensation function | |
| CN216794597U (en) | High-voltage power supply relay protection system of tower crane | |
| CN209609069U (en) | A kind of circuit for controlling motor with temperature control | |
| CN212908626U (en) | Low-voltage outlet cabinet |
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: 20191210 |