CN206331053U - A kind of multifunctional electric sag generator - Google Patents
A kind of multifunctional electric sag generator Download PDFInfo
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- CN206331053U CN206331053U CN201621360513.4U CN201621360513U CN206331053U CN 206331053 U CN206331053 U CN 206331053U CN 201621360513 U CN201621360513 U CN 201621360513U CN 206331053 U CN206331053 U CN 206331053U
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- 238000012360 testing method Methods 0.000 claims description 39
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- 230000008859 change Effects 0.000 claims description 10
- 238000004458 analytical method Methods 0.000 claims description 6
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Abstract
The utility model provides a kind of multifunctional electric sag generator, and the device includes the primary system for producing Voltage Drop and the electrical secondary system for controlling and protecting the primary system；The primary system includes：Taking can transformer, switch cubicle, matrix form current-limiting reactor group, matrix form short-circuit reactance device group and single-phase contactor；The electrical secondary system includes monitoring system, control system, protection system and record wave system system；The electrical secondary system and described take can be provided with uninterrupted power source UPS between the low-pressure side of transformer；Described take can transformer, service entrance switch, by-pass switch, outlet switch series connection；The matrix form current-limiting reactor group X1 is in parallel with the by-pass switch；The matrix form current-limiting reactor group X1, short switch, matrix form short-circuit reactance device group X2, the series connection of single-phase contactor.The technical scheme circuit realiration that the utility model is provided is simple, and the ability for suppressing interference is strong.
Description
Technical field
The utility model is related to a kind of voltage sag generator, and in particular to one kind is applied to Wind turbines and photovoltaic is inverse
Become the voltage sag generator of device low voltage ride-through capability test.
Background technology
At present in China's field of new energy generation, the ratio shared by wind-power electricity generation and photovoltaic generation is increasing, and this two
Planting influence of the electricity generation system to power network also increasingly can not be ignored.It is all intermittent energy source that the general character of the two, which is, and according to
The characteristics of China's wind-force source and solar energy resources, most of the two is all to access power network in the way of extensive concentration is accessed.When
When grid collapses cause grid entry point Voltage Drop, once Wind turbines or the automatic off-grid of photovoltaic DC-to-AC converter are likely to result in electricity
The collapse of net voltage and frequency, has a strong impact on the safe and stable operation of power network, makes wind-force and solar energy both clean energy resourcies
Using being restricted.Therefore, China promulgates《Wind power plant access power system technology regulation》And《Photovoltaic plant accesses power train
System technical stipulation》Make regulation to the low voltage ride-through capability of grid-connected new energy equipment, and it is current general
Method of testing is that new energy equipment is tested using the voltage sag generator for meeting dependence test specification.
, will to Voltage Drop depth and form in relevant regulations due to the difference on Wind turbines and photovoltaic DC-to-AC converter principle
Ask also different.Wherein 20% is dropped to for Wind turbines requirement continue 625ms Wind turbines not off-grid, wind after voltage recovery
The voltage of group of motors returns to the 90% of rated voltage in 2s, and dropping to 0% for photovoltaic DC-to-AC converter requirement continues 150ms,
It is then returned to 20% lasting 475ms and finally recovers rated voltage.Because the form fallen is different, therefore current main inspection
Survey method carries out falling survey to Wind turbines and photovoltaic DC-to-AC converter respectively for the drop generators for falling form using difference respectively
Examination.So significantly increase the cost of testing agency's acquisition expenses.
In addition, most of current test equipment changes equiva lent impedance using reactor tap is manually changed, from
And obtain expected Voltage Drop depth.Such a method, changes the electric discharge that is required for when falling depth having a power failure, into hyperbaric chamber every time
Tap is manually changed, such a method security is relatively low, and automaticity is not high.Meanwhile, traditional voltage sag generator,
General examination point is Voltage Drop depth, does not examine short circuit current flow, the test for needing to examine short circuit current flow for some, it is impossible to
Realize well.
To solve the above problems, the utility model provides a kind of applicable Wind turbines, low voltage ride through of photovoltaic inverter and surveyed
The voltage sag generator of the Voltage Drop test of examination and other special shapes.
Utility model content
The utility model provides a kind of multifunctional electric sag generator, and the device is connected in the form of impedance partial pressure
Between Wind turbines, photovoltaic DC-to-AC converter or other equipment under tests and power network.
The utility model provides a kind of multifunctional electric sag generator, and the device includes being used to produce Voltage Drop
Primary system and the electrical secondary system for controlling and protecting described device；
The primary system includes：Taking can transformer, switch cubicle, matrix form current-limiting reactor group X1, matrix form short circuit electricity
Anti- device group X2 and single-phase contactor；
The electrical secondary system includes for layered distribution type structure：Monitoring system, control system, protection system and record wave system
System；
The electrical secondary system and described take can be provided with uninterrupted power source UPS between the low-pressure side of transformer.
The switch cubicle includes：Service entrance switch CB1, by-pass switch CB2, outlet switch CB3, short switch CB4, current limliting are multiple
Combination switch and short-circuit combination switch；
In primary system, described take can transformer, service entrance switch CB1, by-pass switch CB2, outlet switch CB3 series connection；
The matrix form current-limiting reactor group X1 is in parallel with the by-pass switch CB2；
The matrix form current-limiting reactor group X1, short switch CB4, matrix form short-circuit reactance device group X2, single-phase contactor
Series connection.
The matrix form current-limiting reactor group X1 includes the three-phase reactor of series connection, each three-phase reactor limit in parallel
Flow combination switch；By changing the folding condition of current limliting combination switch before Voltage Drop, change matrix form current-limiting reactor group X1
Equiva lent impedance.
The matrix form short-circuit reactance device X2 includes the three-phase reactor of series connection, the short circuit in parallel of each three-phase reactor
Combination switch；By changing the folding condition of short-circuit combination switch before Voltage Drop, change matrix form short-circuit reactance device group X2's
Equiva lent impedance.
The single-phase contactor end is provided with ground connection point, the test for being grounded system or isolated neutral system
Function.
The monitoring system is used for monitoring and control to described device, including monitoring module and analysis module；
The monitoring module is the man-machine interface of device, and the monitoring and control to equipment are completed by monitoring module；It is described
Analysis module is used for the processing of Wave data, to receive and calculate whether Voltage Drop meets the requirements automatically after recorder data,
Whether equipment under test passes through test.
The control system is used for the Automated condtrol to described device, including logic module, I/O module, A/D module；
The logic module is connected by Ethernet with the monitoring system, and the logic module passes through inner high speed bus
It is connected with the I/O module and the A/D module；
The protection system is used for the protection to described device and operating personnel, including protection module, I/O module, AD moulds
Block；
The protection module is connected by Ethernet with the monitoring system, and the protection module passes through inner high speed bus
It is connected with the I/O module and the A/D module.
The collection united for data in experimentation of record wave system, including data processing module, I/O module, A/D module,
Memory module；
The data processing module is connected by Ethernet with the monitoring system, and the data processing module passes through inside
High-speed bus is connected with the I/O module and the A/D module.
With immediate prior art ratio, the technical scheme that the utility model is provided has following excellent effect：
(1) the utility model provides a kind of multifunctional electric sag generator, and the device can provide diversified forms
Voltage Drop, can be applied to the test of the other field such as Wind turbines, photovoltaic DC-to-AC converter low voltage ride-through capability and short-circuit test etc.；
(2) the utility model has used matrix form reactor group and combination switch to control first on primary system, is combined
Switch has powered division ability, and being avoided using combination switch can only act once only with by-pass switch and short switch
Problem, is fallen by setting the action logic of by-pass switch, short switch and combination switch to complete the continuous of different depth twice,
The problem of acting inconsistent while multiple combination switches can be solved by setting the different action delay times；Combination switch
More traditional switch is compared, and Costco Wholesale has advantage, and electric current of make-and-break size can be set by design and protection to reactor
Count limit value；Installation dimension is greatly reduced, automaticity is improved, and realize that the continuous of the voltage of different depth falls twice
Fall.
(3) the utility model in process of the test without manual intervention, compared with the mode that traditional manual is connected, Neng Goutong
Cross control system and be automatically performed the change for falling depth, change short-circuit impedance without having a power failure, improve experiment convenience and operation
Safety coefficient；
(4) the utility model electrical secondary system uses Modular Structure Design, using layered distribution type structure, reduces module
Between coupling, improve the extended capability of device；
(5) coherent signal outside the utility model rich interface, convenient collection equipment under test；
(6) the utility model integrated level is high, and man-machine interface is friendly, and all controls can be completed by background monitoring system
Function, it is possible to achieve from dynamic test, be automatically performed the collection of fall-down test and recorder data；
(7) the utility model has complete defencive function, is also equipped with addition to conventional electric quantity protective and non-ionizing energy loss
P.P protects；
(8) the utility model circuit realiration is simple, and the ability for suppressing interference is strong.
Brief description of the drawings
Fig. 1 is a kind of main circuit diagram of multifunctional electric sag generator primary system of the utility model；
Fig. 2 is a kind of network structure of multifunctional electric sag generator electrical secondary system of the utility model.
Embodiment
The utility model is described in more detail below in conjunction with the accompanying drawings：
The utility model provides a kind of multifunctional electric sag generator, and the device includes being used to produce Voltage Drop
Primary system and the electrical secondary system for controlling and protecting described device；
As shown in figure 1, the primary system includes：Taking can transformer, switch cubicle, matrix form current-limiting reactor group X1, square
Configuration short-circuit reactance device group X2 and single-phase contactor；
It is described to take energy transformer to be powered for the electrical secondary system to device, positioned at device end of incoming cables, in order to meet different electricity
Press the test condition of the system under test (SUT) of grade, this take can transformer include multiple taps, wait different grades of system voltage turn
Turn to the secondary device operating voltage of standard.
The switch cubicle includes：Service entrance switch CB1, by-pass switch CB2, outlet switch CB3, short switch CB4, current limliting are multiple
Combination switch and short-circuit combination switch；
Described take can transformer, service entrance switch CB1, by-pass switch CB2, outlet switch CB3 series connection；
The outlet switch CB3 is connected with equipment under test, when described device carries out no-load test, and outlet switch CB3 is opened,
Design impedance during no load test can be avoided to falling the influence of depth.
The matrix form current-limiting reactor group X1 is in parallel with the by-pass switch CB2；It is described during equipment under test normal power generation
By-pass switch CB2 is closed, and the current-limiting reactor group X1 is in bypass condition；
The current-limiting reactor group X1, including following effect：
Undertake partial pressure work during Voltage Drop；
Influence a little to higher level's power network is fallen in limitation when short-circuit, by reasonably setting reactor group X1 parameters, can be
The influence of higher level's line voltage is limited within 5%.
The matrix form current-limiting reactor group X1, short switch CB4, matrix form short-circuit reactance device group X2, single-phase contactor
It is sequentially connected in series；During equipment under test normal power generation, the short switch CB4 be in opening situation, the short-circuit reactance device group X2 with
Power network disconnects；
The matrix form current-limiting reactor group X1 includes the three-phase reactor of series connection, each three-phase reactor limit in parallel
Flow combination switch；By changing the folding condition of current limliting combination switch before Voltage Drop, change matrix form current-limiting reactor group X1
Equiva lent impedance.
The matrix form short-circuit reactance device X2 includes the three-phase reactor of series connection, the short circuit in parallel of each three-phase reactor
Combination switch；By changing the folding condition of short-circuit combination switch before Voltage Drop, change matrix form short-circuit reactance device group X2's
Equiva lent impedance.
The short switch CB4 and matrix form current-limiting reactor group X1 tie point is drop test point, by changing
Become the matrix form current-limiting reactor group X1 and the matrix form short-circuit reactance device group X2 impedance value ratio, change drop test point
Fall depth.
The single-phase contactor end is provided with ground connection point, the test for being grounded system or isolated neutral system
Function.
As shown in Fig. 2 the electrical secondary system includes：Monitoring system, control system, protection system and record wave system system；
The electrical secondary system and described take can be provided with uninterrupted power source UPS between the low-pressure side of transformer.
The electrical secondary system is designed using distributed frame, and to reduce the coupling between each module, each module connects simultaneously
Enter background monitoring system, while the integrated recorder data analytic function of background monitoring system, to improve the convenient of equipment monitor control
Property.
The monitoring system is used for monitoring and control to described device, including monitoring module and analysis module；
The monitoring module is the man-machine interface of device, and the monitoring and control to equipment are completed by monitoring module；It is described
Analysis module is used for the processing of Wave data, to receive and calculate whether Voltage Drop meets the requirements automatically after recorder data,
Whether equipment under test detects whether off-grid and power recovery situation by test.
The control system is used for the Automated condtrol to described device, including logic module, I/O module, A/D module；Institute
State logic module to be connected with the monitoring system by Ethernet, the logic module passes through inner high speed bus and the IO moulds
Block and A/D module connection；The logic module is the core of control system, when logic module receives what monitoring system was issued
After control command, DI modules can be operated according to logic of propositions so as to realize the change for falling depth or complete fall-down test.
For fall-down test, when logic module receives " Manual test " order, logic module will be tested immediately；Work as logic module
When receiving " from dynamic test " order, logic module is according to the condition automatic decision of setting, when the power of fan size machine duration
It will be tested automatically when being satisfied by requiring.Between experiment, the logic module is united by I/O module triggering record wave system, so that real
It is now automatic to record wave energy.When fall-down test is no-load test, the logic module can be according to the division of CB4 and combination switch
Time delayses, to realize the correctness of drop-out time, and the uniformity that combination switch group is acted.The I/O module is used for switching value
Collection and action command transmission.The A/D module is used for the collection of analog quantity and the calculating of virtual value.
The protection system is used for the protection to described device and operating personnel, including protection module, I/O module, AD moulds
Block；The protection module is connected by Ethernet with the monitoring system, and the protection module passes through inner high speed bus and institute
State I/O module and A/D module connection.The protection module detect in real time the I/O module and A/D module collection switching value and
Analog quantity, after working value and actuation time satisfaction, issues trip signal, and report monitoring system by the I/O module.
The protection of protection system includes electric quantity protective and non-ionizing energy loss two parts, and wherein electric quantity protective includes overcurrent protection, overvoltage guarantor
Protect, cross complex protection, differential protection etc., non-ionizing energy loss includes smog protection, equipment overtemperature prote etc..Protection system is except offer
To also providing personal protection outside the protection of equipment, after hyperbaric chamber door opening is detected, apparatus system automatic trip is concurrently spoken
Light alarm.After protection act, the protection module is united again by I/O module triggering record wave system.
The collection united for data in experimentation of record wave system, including data processing module, I/O module, A/D module,
Memory module；The data processing module is connected by Ethernet with the monitoring system, and the data processing module passes through interior
Portion's high-speed bus is connected with the I/O module and the A/D module.After the logic module receives the order for starting record ripple,
Switching value is gathered by the I/O module, analog quantity, after treating that once recording ripple terminates, the logic module are gathered by A/D module
Then the storage of record ripple module is uploaded in a storage module first, loss of data is caused to prevent communication disruption.It is simultaneously described
The external interface that wave system system provides diversified forms is recorded, equipment under test parameter can be conveniently accessed.
To protect secondary device from overvoltage impact, the multifunctional electric falling device is filled provided with corresponding overvoltage protection
Put.
Finally it should be noted that：Above example is merely to illustrate the technical solution of the utility model rather than it is protected
The limitation of scope, although the application is described in detail with reference to above-described embodiment, those of ordinary skill in the art
It should be understood that：Those skilled in the art, which to read, still the embodiment of application can be carried out after the application a variety of changes, repaiies
Change or equivalent, but these changes, modification or equivalent, apply pending claims it
It is interior.
Claims (10)
1. a kind of multifunctional electric sag generator, it is characterised in that the device includes being used to produce Voltage Drop once
System and the electrical secondary system for controlling and protecting described device；
The primary system includes：Taking can transformer, switch cubicle, matrix form current-limiting reactor group X1, matrix form short-circuit reactance device
Group X2 and single-phase contactor；
The electrical secondary system includes for layered distribution type structure：Monitoring system, control system, protection system and record wave system system；
The electrical secondary system and described take can be provided with uninterrupted power source UPS between the low-pressure side of transformer.
2. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the switch cubicle includes：Inlet wire
Switch CB1, by-pass switch CB2, outlet switch CB3, short switch CB4, current limliting combination switch and short-circuit combination switch.
3. multifunctional electric sag generator as claimed in claim 2, it is characterised in that described to take energy in primary system
Transformer, service entrance switch CB1, by-pass switch CB2, outlet switch CB3 series connection；
The matrix form current-limiting reactor group X1 is in parallel with the by-pass switch CB2；
The matrix form current-limiting reactor group X1, short switch CB4, matrix form short-circuit reactance device group X2, the series connection of single-phase contactor.
4. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the matrix form current-limiting reactor
Group X1 includes the three-phase reactor of series connection, each three-phase reactor current limliting combination switch in parallel；By changing before Voltage Drop
Become the folding condition of current limliting combination switch, change matrix form current-limiting reactor group X1 equiva lent impedance.
5. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the matrix form short-circuit reactance device
X2 includes the three-phase reactor of series connection, one in parallel short-circuit combination switch of each three-phase reactor；By changing before Voltage Drop
The folding condition of short-circuit combination switch, changes matrix form short-circuit reactance device group X2 equiva lent impedance.
6. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the single-phase contactor end is set
There is ground connection point, the test function for being grounded system or isolated neutral system.
7. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the monitoring system is used for institute
State the monitoring and control of device, including monitoring module and analysis module；
The monitoring module is the man-machine interface of device, and the monitoring and control to equipment are completed by monitoring module；The record ripple
Analysis module is used for the processing of Wave data, to receive and calculate whether Voltage Drop meets the requirements automatically after recorder data, is tested
Whether equipment passes through test.
8. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the control system is used for institute
State the Automated condtrol of device, including logic module, I/O module, A/D module；
The logic module is connected by Ethernet with the monitoring system, and the logic module passes through inner high speed bus and institute
State I/O module and A/D module connection.
9. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the protection system is used for institute
State device and the protection of operating personnel, including protection module, I/O module, A/D module；
The protection module is connected by Ethernet with the monitoring system, and the protection module passes through inner high speed bus and institute
State I/O module and A/D module connection.
10. multifunctional electric sag generator as claimed in claim 1, it is characterised in that the record wave system is united for real
The collection of data during testing, including data processing module, I/O module, A/D module, memory module；
The data processing module is connected by Ethernet with the monitoring system, and the data processing module passes through inner high speed
Bus is connected with the I/O module and the A/D module.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621360513.4U CN206331053U (en) | 2016-12-13 | 2016-12-13 | A kind of multifunctional electric sag generator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621360513.4U CN206331053U (en) | 2016-12-13 | 2016-12-13 | A kind of multifunctional electric sag generator |
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| CN206331053U true CN206331053U (en) | 2017-07-14 |
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| CN201621360513.4U Expired - Fee Related CN206331053U (en) | 2016-12-13 | 2016-12-13 | A kind of multifunctional electric sag generator |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108614169A (en) * | 2016-12-13 | 2018-10-02 | 中电普瑞科技有限公司 | A kind of multifunctional electric sag generator |
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2016
- 2016-12-13 CN CN201621360513.4U patent/CN206331053U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108614169A (en) * | 2016-12-13 | 2018-10-02 | 中电普瑞科技有限公司 | A kind of multifunctional electric sag generator |
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Granted publication date: 20170714 |