CN109004673A - A kind of subway Way of Regenerating Energy Feedback device DC voltage detection and control method - Google Patents
A kind of subway Way of Regenerating Energy Feedback device DC voltage detection and control method Download PDFInfo
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- CN109004673A CN109004673A CN201810895656.2A CN201810895656A CN109004673A CN 109004673 A CN109004673 A CN 109004673A CN 201810895656 A CN201810895656 A CN 201810895656A CN 109004673 A CN109004673 A CN 109004673A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
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Abstract
The present invention relates to a kind of subway Way of Regenerating Energy Feedback device DC voltage detection and control methods, including carry out detection to DC voltage and protect and carry out dynamic adjustment to direct current starting voltage threshold and determine two step of direct voltage reference value.For perturbed problem present in DC Traction Network, voltage detecting and guard method are proposed.The disturbance time that DC grid system is superimposed upon in electric power supply system for subway is generally Microsecond grade, when interference occurs, can be effectively filtered out after applying the present invention to the interference being superimposed upon in DC grid, prevent the mistake of equipment from protecting；When true over-voltage or under-voltage fault occurs in DC grid, since guard time is also no more than 1ms, the response time requirement of system is fully met.For the problem that AC voltage fluctuations bring circulation or response speed are slower, proposes DC voltage starting threshold value and control adaptive control method.This method is realized simply, thus the problem that the circulation or response speed that effectively avoid exchange network pressure wave zone from are excessively slow.
Description
Technical field
The present invention relates to power electronic technique and automatic Test and control field, and in particular to a kind of subway Regenerated energy
Measure feedback device DC voltage detection and control method.
Background technique
Ground placed type subway regenerating braking energy inversion feedback device (can hereinafter referred to as present device) is installed on subway station
Traction decompression mixing electric substation, when railcar enters the station, mechanical energy when may be implemented to brake in subway is converted into exchange
Electric energy, and power grid is fed back to, it uses, realizes regenerating braking energy again using or for other towing vehicles for station load
The purpose of secondary recycling.When device works in rectification mode, traction rectifier unit can be cooperated to provide energy to DC side simultaneously
Amount can reduce the power output of traction rectifier unit, improve the reliability of railcar power supply system.
Electric power supply system for subway needs to guarantee high reliability, can present the DC terminal connection DC Traction Network of device, exchange end and connect
The medium voltage network of exchange 35kV (10kV) is connect, wherein DC traction network pressure is to be obtained by middle pressure AC network by Rectification Power Factor,
Therefore high requirement is proposed to the control stability that can present device.In order to improve the stability and stable state accuracy that can present device,
The general double-loop control strategy for using outer voltage combination current inner loop.That is real-time detection DC voltage, when braking can
When amount causes voltage to be more than the starting threshold value of equipment, that is, start to start closed loop control mode, by DC voltage control in target value,
Energy in bidirectional flow realizes energy feedback or traction rectifier function.
In above-mentioned double-loop control strategy, particularly critical is become to the Detection & Controling method of DC side network pressure.And it examines
The rapidity and accuracy of method of determining and calculating.The speed of detection algorithm will affect the response speed of closed-loop system, if only with instantaneous
Value detects to protect, and since electric power supply system for subway is there are biggish interference and burr, equipment can often report DC over-voltage by mistake
Or under-voltage fault and cause the malfunction of device；RMS to DC can guarantee the accuracy of detection, but response speed can become
Slowly, the rapidity of device tracking is influenced.
Control to DC voltage, current control mode are essentially all direct sampling direct current primary voltage, and with
The starting voltage threshold that device can be presented compares, and after setting, when operation can be kept fixed constant the threshold value.Then more than the value
Equipment starts inversion feedback (or traction rectifier), when brake (or traction) energy is gradually decrease to zero, then exit inversion feedback (or
Traction rectifier) process.And exchange network pressure it is higher or lower when, DC side network pressure can follow corresponding change, therefore start fixed
In the case where voltage threshold, when AC network presses through it is high when, the floating voltage of DC side diode rectification unit may be more than to open
Dynamic voltage threshold, causes diode rectification unit and can present to generate circulation between device, will increase the loss of equipment；Work as exchange
When network pressure is too low, in the case that starting threshold value is fixed, it will cause the problems that the response speed of feedback is excessively slow.
Summary of the invention
1, technical problem to be solved:
In view of the above technical problems, this method provides a kind of detection of subway Way of Regenerating Energy Feedback device DC voltage and control
Method.By the way that the DC voltage that can present device is detected and protected, effect excludes caused by burr, interference etc. accidentally this method
Judgement guarantees the rapidity and accuracy of detection；Method also provides for start voltage threshold to the direct current that can present device to carry out
Dynamic adjustment and simultaneously determine direct voltage reference value, be able to solve exchange side overtension or too low issuable circulation or
The slack-off problem of response speed, ensure that equipment reliability of operation.
2, technical solution:
A kind of subway Way of Regenerating Energy Feedback device DC voltage detection and control method, which is characterized in that including following step
It is rapid: step 1: the DC voltage that can present device being detected and protected；It specifically includes:
1.1 direct current voltage sensor devices are to the DC side of subway Way of Regenerating Energy Feedback device with preset sample frequency fN
It is acquired voltage value, collected DC voltage instantaneous value is Vdc；And collected DC voltage instantaneous value Vdc is passed through
AD sampling unit input controller.
1.2 controllers will receive instantaneous voltage Vdc and preset overvoltage protection value VOV, under-voltage protection value VLVIt carries out
In real time relatively.If detecting that DC voltage instantaneous value Vdc is greater than overvoltage protection value VOVWhen, subway Way of Regenerating Energy Feedback fills at this time
There are the possibility of over-voltage for the voltage for the DC side set；Carry out step 1.3.If it is pre- to detect that DC voltage instantaneous value Vdc is less than
If under-voltage protection value VLVI.e. there are under-voltage possibility for the voltage of the DC side of subway Way of Regenerating Energy Feedback device at this time；Carry out step
1.4。
1.3 since detect may over-voltage at the time of, to the voltage of the DC side of subway Way of Regenerating Energy Feedback device into
The sampling of row n times, and by the result sampled every time and overvoltage protection value VOVIt is compared；If sampled value occurs being greater than overvoltage protection
Value VOV, then really there is over-voltage fault in judgment means；If being greater than overvoltage protection value V without sampled valueOV, then judgement is not present
Over-voltage fault resets count value, and is judged to interfering generation, and equipment continues to operate normally.
1.4 since detect may be under-voltage at the time of, to the voltage of the DC side of subway Way of Regenerating Energy Feedback device into
The sampling of row n times, and by the result sampled every time and under-voltage protection value VLVIt is compared；If sampled value occurs under-voltage less than presetting
Protection value VLV, then really there is under-voltage fault in judgment means；If being less than default under-voltage protection value V without sampled valueLV, then sentence
It is disconnected that under-voltage fault is not present, count value is reset, and be judged to interfering generation, equipment continues to operate normally.Wherein above-mentioned N value
It chooses and sample frequency fNCorrelation meets relationship:
Step 2: dynamic adjustment is carried out to direct current starting voltage threshold and determines direct voltage reference value；Its detailed process
Are as follows:
2.1 pairs of DC voltages that can present device are acquired, and according to the default starting voltage threshold of the result of acquisition
Initial value Vth0, corresponding at this time to exchange side network voltage rated value USN。
2.2 acquire subway Way of Regenerating Energy Feedback device in real time using voltage sensor exchange end three-phase voltage Usa, Usb,
Usc, three-phase voltage Usa, Usb, Usc pass through AD conversion input controller；Controller calculates having for three-phase AC grid voltage
Valid value Uarms、Ubrms、Ucrms, and calculate the average value of the virtual value of three-phase AC grid voltage: Usav=(Uarms+Ubrms
+Ucrms)/3。
2.3 define DC voltage regulation coefficient Kus=Usav/USN。
The real value V of 2.4 definition starting voltage thresholdsth: Vth=Vtho* Kus, then the reference value of DC voltage control:
Vref=Vth- Δ v；Wherein, Δ v is overshoot, and size is tens volts of voltages, is positive value under inversion feedback mode, is rectifying
It is negative value under mode.
3, the utility model has the advantages that
(1) this method is for perturbed problem present in DC Traction Network, proposes a kind of voltage detecting and guard method.
The disturbance time due in electric power supply system for subway, being superimposed upon DC grid system is generally Microsecond grade, when interference occurs, uses
After the present invention, the interference being superimposed upon in DC grid can be effectively filtered out, prevent the mistake of equipment from protecting；When DC grid goes out
When now true over-voltage or under-voltage fault, since guard time is also no more than 1ms, the response time requirement of system is fully met,
It ensure that the stable operation of device.
(2) this method problem slower for AC voltage fluctuations bring circulation or response speed proposes a kind of straight
The galvanic electricity pressure starting threshold value control method adaptive with control.This method is realized simply, direct current can be started voltage threshold and ginseng
Examining value, dynamic adjusts in real time, thus the problem that the circulation or response speed that effectively avoid exchange network pressure wave zone from are excessively slow.
Detailed description of the invention
Fig. 1 is DC voltage detection and protection flow chart in the present invention；
Fig. 2 is that the direct current in the present invention starts the adjustment of voltage threshold dynamic and determines the control flow of direct voltage reference value
Figure.
Specific embodiment
This method is described in detail with reference to the accompanying drawing.
As shown in Fig. 1 in the present invention DC voltage detection and protection flow chart, as shown in the figure to device can be presented
DC voltage detected and protected；Specifically include: 1.1 direct current voltage sensor devices fill subway Way of Regenerating Energy Feedback
The DC side set is with preset sample frequency fNIt is acquired voltage value, collected DC voltage instantaneous value is Vdc；And it will adopt
The DC voltage instantaneous value Vdc collected passes through AD sampling unit input controller.1.2 controllers will receive instantaneous voltage
Vdc and preset overvoltage protection value VOV, under-voltage protection value VLVCompared in real time.If detecting DC voltage instantaneous value Vdc
Greater than overvoltage protection value VOVWhen, there are the possibility of over-voltage for the voltage of the DC side of subway Way of Regenerating Energy Feedback device at this time；It carries out
Step 1.3.If detecting that DC voltage instantaneous value Vdc is less than default under-voltage protection value VLVThat is subway Way of Regenerating Energy Feedback at this time
There are under-voltage possibility for the voltage of the DC side of device；Carry out step 1.4.1.3 since at the time of detecting possible over-voltage, right
The voltage of the DC side of subway Way of Regenerating Energy Feedback device carries out n times sampling, and by the result sampled every time and overvoltage protection value
VOVIt is compared；If sampled value occurs being greater than overvoltage protection value VOV, then really there is over-voltage fault in judgment means；If not yet
There is sampled value to be greater than overvoltage protection value VOV, then over-voltage fault is not present in judgement, count value is reset, and be judged to interfering generation,
Equipment continues to operate normally.1.4 since at the time of detecting possible under-voltage, to the DC side of subway Way of Regenerating Energy Feedback device
Voltage carry out n times sampling, and by the result sampled every time and under-voltage protection value VLVIt is compared；If sampled value is less than
Default under-voltage protection value VLV, then really there is under-voltage fault in judgment means；If being less than default under-voltage protection value without sampled value
VLV, then under-voltage fault is not present in judgement, count value is reset, and be judged to interfering generation, equipment continues to operate normally；On wherein
State selection and the sample frequency f of N valueNCorrelation meets relationship:
In the above process, direct current voltage sensor acquires DC voltage instantaneous value Vdc in real time, is sent into the AD sampling of controller
Unit, to the DC voltage with sample frequency fNReal-time sampling, and with overvoltage protection value VOV, under-voltage protection value VLVIn real time relatively,
If over-voltage or under-voltage fault are not present always, device is operated normally；When detecting that a certain moment occurs DC over-voltage or owes
When pressing failure, timing from this moment is carried out continuously n times sampling, and sampling is made whether over-voltage or under-voltage comparison every time
Judgement.If there are still over-voltage or under-voltage signal, then judging that failure really occurs, device can block arteries and veins immediately after judging herein
Punching, and carry out shutdown action.If discovery fault-signal disappears after judging herein, count value is reset, and device maintains normal fortune
Row is unaffected.
Start voltage threshold dynamic as shown in Fig. 2 for direct current and adjusts and determine the control flow of direct voltage reference value
Figure, comprising the following steps: 2.1 pairs of DC voltages that can present device are acquired, and according to the default starting electricity of the result of acquisition
Press the initial value V of threshold valueth0, corresponding at this time to exchange side network voltage rated value USN。
2.2 acquire subway Way of Regenerating Energy Feedback device in real time using voltage sensor exchange end three-phase voltage Usa, Usb,
Usc, three-phase voltage Usa, Usb, Usc pass through AD conversion input controller；Controller calculates having for three-phase AC grid voltage
Valid value Uarms、Ubrms、Ucrms, and calculate the average value of the virtual value of three-phase AC grid voltage: Usav=(Uarms+Ubrms
+Ucrms)/3。
2.3 define DC voltage regulation coefficient Kus=Usav/USN。
The real value V of 2.4 definition starting voltage thresholdsth: Vth=Vtho* Kus, then the reference value of DC voltage control:
Vref=Vth- Δ v；Wherein, Δ v is overshoot, and size is tens volts of voltages, is positive value under inversion feedback mode, is rectifying
It is negative value under mode.
In above process, according to DC voltage sampled value, the initial value V of setting starting voltage thresholdth0, according to real-time
Instantaneous value Usa, Usb, the Usc for sampling obtained AC network are sent into controller unit by three-phase voltage after AD conversion, and
Calculate the virtual value U of three-phase AC grid voltagearms、Ubrms、UcrmsAnd calculate being averaged for three-phase AC grid voltage effective value
Value Usav=(Uarms+Ubrms+Ucrms)/3.Corresponding exchange side network voltage rated value USN, calculate DC voltage adjustment system
Number Kus=Usav/USN.The initial value V of the regulation coefficient and starting voltage thresholdth0The two is multiplied, and obtains starting voltage threshold
Real value: Vth=Vtho*Kus.Direct current pressure ring uses proportional plus integral control (PI control), super with certain overshoot when control
Tune amount is denoted as Δ v.Then the reference value of DC voltage is Vref=Vth- Δ v, wherein Δ v value is generally tens volts, and (inversion is returned
When feedback mode, overshoot is positive value；When rectification mode, overshoot is negative value).
By detecting control method above, device can be presented in normal course of operation, can effectively avoid on DC side power grid
Impulse disturbances, while the generation of true voltage failure, holding meanss reliability of operation can be timely responded to again.Meanwhile it is logical
The real-time fluctuations situation for crossing monitoring exchange side network pressure, obtains a DC voltage regulation coefficient Kus, which is added to direct current
In voltage starting threshold value and reference value, it can effectively avoid exchange side net voltage fluctuation to the control bring negative effect of direct current ring, protect
Having demonstrate,proved can the long-term and reliable and stable operation of feedback system.
Although the present invention has been described by way of example and in terms of the preferred embodiments, they be not it is for the purpose of limiting the invention, it is any ripe
This those skilled in the art is practised, without departing from the spirit and scope of the invention, can make various changes or retouch from working as, therefore guarantor of the invention
Shield range should be subject to what claims hereof protection scope was defined.
Claims (1)
1. a kind of subway Way of Regenerating Energy Feedback device DC voltage detection and control method, which comprises the following steps:
Step 1: the DC voltage that can present device is detected and is protected；It specifically includes:
1.1 direct current voltage sensor devices are to the DC side of subway Way of Regenerating Energy Feedback device with preset sample frequencyNIt carries out
Collection voltages value, collected DC voltage instantaneous value are Vdc；And collected DC voltage instantaneous value Vdc is adopted by AD
Sample unit input controller；
1.2 controllers will receive instantaneous voltage Vdc and preset overvoltage protection value VOV, under-voltage protection value VLVCompared in real time
Compared with；
If detecting that DC voltage instantaneous value Vdc is greater than overvoltage protection value VOVWhen, subway Way of Regenerating Energy Feedback device at this time
There are the possibility of over-voltage for the voltage of DC side；Carry out step 1.3；
If detecting that DC voltage instantaneous value Vdc is less than default under-voltage protection value VLVThat is subway Way of Regenerating Energy Feedback device at this time
The voltage of DC side there are under-voltage possibility；Carry out step 1.4；
1.3 since at the time of detecting possible over-voltage, carries out n times to the voltage of the DC side of subway Way of Regenerating Energy Feedback device
Sampling, and by the result sampled every time and overvoltage protection value VOVIt is compared；If sampled value occurs being greater than overvoltage protection value
VOV, then really there is over-voltage fault in judgment means；If being greater than overvoltage protection value V without sampled valueOV,Then over-voltage is not present in judgement
Failure resets count value, and is judged to interfering generation, and equipment continues to operate normally；
1.4 since at the time of detecting possible under-voltage, carries out n times to the voltage of the DC side of subway Way of Regenerating Energy Feedback device
Sampling, and by the result sampled every time and under-voltage protection value VLVIt is compared；If sampled value occurs being less than default under-voltage protection
Value VLV, then really there is under-voltage fault in judgment means；If being less than default under-voltage protection value V without sampled valueLV,Then judge not deposit
In under-voltage fault, count value is reset, and is judged to interfering generation, equipment continues to operate normally；
Wherein the selection of above-mentioned N value is related to sample frequency, meets relationship:；
Step 2: dynamic adjustment is carried out to direct current starting voltage threshold and determines direct voltage reference value；Its detailed process are as follows:
2.1 pairs of DC voltages that can present device are acquired, and according to the initial of the default starting voltage threshold of the result of acquisition
Value Vth0, corresponding at this time to exchange side network voltage rated value USN ；
2.2 acquire exchange end three-phase voltage Usa, Usb, Usc of subway Way of Regenerating Energy Feedback device using voltage sensor in real time,
Three-phase voltage Usa, Usb, Usc pass through AD conversion input controller；Controller calculates the virtual value of three-phase AC grid voltage
Uarms、Ubrms、Ucrms, and calculate the average value of the virtual value of three-phase AC grid voltage: Usav=(Uarms+Ubrms+
Ucrms)/3；
2.3 define DC voltage regulation coefficient Kus=Usav/USN；
The real value V of 2.4 definition starting voltage thresholdsth: Vth=Vtho*Kus,
The then reference value of DC voltage control: Vref=Vth- Δ v；Wherein, Δ v is overshoot, and size is tens volts of voltages,
It is positive value under inversion feedback mode, is negative value under rectification mode.
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| CN201810895656.2A CN109004673B (en) | 2018-08-08 | 2018-08-08 | Direct-current voltage detection and control method for subway regenerative energy feedback device |
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| CN201810895656.2A CN109004673B (en) | 2018-08-08 | 2018-08-08 | Direct-current voltage detection and control method for subway regenerative energy feedback device |
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| CN109004673B CN109004673B (en) | 2021-12-14 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110380437A (en) * | 2019-07-03 | 2019-10-25 | 南京亚派科技股份有限公司 | A kind of super capacitor energy storage device direct current network pressure self-adaptation control method |
| CN110435485A (en) * | 2019-07-08 | 2019-11-12 | 许继集团有限公司 | A kind of progress control method, device and medium applied to inversion feedback device |
| CN113422397A (en) * | 2021-06-22 | 2021-09-21 | 思源清能电气电子有限公司 | Automatic control method for energy feedback and rectification of flexible traction power supply device |
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| CN102611142A (en) * | 2012-04-10 | 2012-07-25 | 深圳市合兴加能科技有限公司 | Power generator parallel operation system free of restraint of voltage value, frequency and phase difference and method |
| US20140126257A1 (en) * | 2012-05-30 | 2014-05-08 | Astec International Limited | Control circuits for power converters |
| CN106159899A (en) * | 2016-07-14 | 2016-11-23 | 南京亚派科技股份有限公司 | The sensor fault monitoring and protecting device and method of subway energy back feed device |
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| CN102611142A (en) * | 2012-04-10 | 2012-07-25 | 深圳市合兴加能科技有限公司 | Power generator parallel operation system free of restraint of voltage value, frequency and phase difference and method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110380437A (en) * | 2019-07-03 | 2019-10-25 | 南京亚派科技股份有限公司 | A kind of super capacitor energy storage device direct current network pressure self-adaptation control method |
| CN110380437B (en) * | 2019-07-03 | 2022-12-30 | 南京亚派科技股份有限公司 | Self-adaptive control method for direct current network voltage of super-capacitor energy storage device |
| CN110435485A (en) * | 2019-07-08 | 2019-11-12 | 许继集团有限公司 | A kind of progress control method, device and medium applied to inversion feedback device |
| CN113422397A (en) * | 2021-06-22 | 2021-09-21 | 思源清能电气电子有限公司 | Automatic control method for energy feedback and rectification of flexible traction power supply device |
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