CN208636375U - It is a kind of can setting frequency range tractive power supply system frequency domain impedance measurement device - Google Patents
It is a kind of can setting frequency range tractive power supply system frequency domain impedance measurement device Download PDFInfo
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- CN208636375U CN208636375U CN201821103175.5U CN201821103175U CN208636375U CN 208636375 U CN208636375 U CN 208636375U CN 201821103175 U CN201821103175 U CN 201821103175U CN 208636375 U CN208636375 U CN 208636375U
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Abstract
The utility model discloses it is a kind of can setting frequency range tractive power supply system frequency domain impedance measurement device, main composition is: the secondary winding concatenation switch (K) of step-down transformer (T) is followed by disturbance circuit；Microprocessor (MPU) is connected by driving circuit (DC) with the gate pole for disturbing IGBT device in circuit；Disturb circuit mainly by: step-down transformer, diode, IGBT device, resistance form；The frequency domain impedance operator that the device can carry out setting frequency range to tractive power supply system measures；The impedance measurement of tractive power supply system frequency domain is carried out using the device, Measurement and Data Processing amount is small, measurement efficiency is high, the impedance operator measured and accuracy of resonant frequencies are high, more acurrate reliable.
Description
Technical field
The utility model relates to a kind of tractive power supply system frequency domain impedance measurement devices.
Background technique
Ended for the end of the year 2016, China's electric railway total kilometrage up to 7.4 ten thousand kilometers, Railway Electric rate up to 60% with
On, it is more than 80% that electric propulsion, which completes transport task specific gravity,.Meanwhile electric railway is held with 6640 kilometers of every annual of speed
Continuous extension, it is contemplated that the year two thousand thirty, railway electrification mileage will be of about 150,000 kilometers.Most important electric device in electric railway
It is tractive power supply system.Tractive power supply system contains a large amount of perception and capacitive element, and perception is mutually matched with capacitive element
More resonance point can be brought to tractive power supply system.And using electronic power convertor as the electric power machine of power-supply change-over unit
Vehicle can then bring a large amount of harmonic wave to tractive power supply system；Tractive power supply system itself also has a certain amount of harmonic wave.When these
When harmonic frequency and resonance dot frequency match, it may occur that harmonic resonance phenomenon will lead to breaker malfunction, route damage when serious
The problems such as bad, traction motor failure and traction locking.And impedance measurement technique can be accurately obtained the impedance of tractive power supply system
Characteristic, so that the resonance dot frequency of system is accurately acquired, by adding filter at these resonance dot frequencies, to filter out
Harmonic wave at resonance point avoids the generation of harmonic resonance, plays an important role to guarantee tractive power supply system safe and stable operation.
Existing tractive power supply system frequency domain impedance operator measuring device is to analyze, measure the resistance of each frequency point of wide-band
It is anti-, and then obtain the resonance dot frequency of system.Its disturbing signal generating device generate wide-band disturbing signal frequency band fix,
It cannot be adjusted and control；When its frequency band is wide, the resistance that Measurement and Data Processing amount is big, measurement efficiency is low, measures will lead to
Anti- characteristic and accuracy of resonant frequencies are low；And when its frequency band is narrow, will lead to the test leakage of resonance frequency, the impedance operator measured and
Resonance frequency accuracy is low and poor reliability.
Utility model content:
The purpose of the invention of the present invention is to provide the tractive power supply system frequency domain impedances that one kind can set measurement frequency range
Measuring device, the device to tractive power supply system impedance operator can determine the frequency domain impedance measurement of frequency range.
The utility model realize its utility model goal of the invention the technical scheme adopted is that it is a kind of can setting frequency range lead
Draw power supply system frequency domain impedance measurement device, the primary coil including connecing the step-down transformer between contact net and rail, drop
The secondary winding concatenation switch of pressure transformer is followed by disturbance circuit；Current sensor is mounted on the original of contact net and step-down transformer
Between side, voltage sensor is installed in parallel in the primary side port of step-down transformer；Current sensor, voltage sensor and signal tune
Device is managed to be connected；Signal conditioner is connected with microprocessor；Meanwhile microprocessor also passes through IGBT in driving circuit and disturbance circuit
The gate pole of device is connected；
It is characterized by: the disturbance circuit disturbs circuit by positive half cycle and negative half period disturbance circuit forms, in which:
The composition of positive half cycle disturbance circuit is: the upper end of step-down transformer secondary side is connected with the anode of diode one；Two poles
The cathode of pipe one is connected with the collector of IGBT device one, and the emitter of IGBT device one is negative by resistance one and diode three
Extremely it is connected；The anode of diode three is connected with the anode of diode one；The emitter of IGBT device one also passes through resistance three and drop
The lower end of pressure transformer secondary side is connected；The gate pole of IGBT device one is connected with driving circuit；
The composition of negative half period disturbance circuit is: the upper end of step-down transformer secondary side is connected with the cathode of diode two；Two poles
The anode of pipe two is connected with the emitter of IGBT device two, and the collector of IGBT device two is passing through resistance two and diode four just
Extremely it is connected；The cathode of diode four is connected with the cathode of diode two；The collector of IGBT device two also passes through resistance three and drop
The lower end of pressure transformer secondary side is connected；The gate pole of IGBT device two is connected with driving circuit.
The course of work and application method of the utility model are:
A, control signal generates:
Microprocessor generates the chirping of birds signal y (t) of setting frequency range, and the chirping of birds signal y (t) is in frequency change period
Frequency conversion sinusoidal signal interior, that frequency converts linearly over time, mathematic(al) representation are as follows: y (t)=sin (2 π (f0+(f1-f0)t/
Ts) t), wherein t is time, TsFor frequency change period, f0For the lowest frequency value of setting frequency range, f1Most for setting frequency range
High frequency values；Microprocessor obtains frequency from f by frequency conversion sinusoidal signal y (t)0Linear transformation is to f1Chirping of birds control signal yP
(t),Chirping of birds is controlled signal y by driving circuit by closure switch, microprocessorP(t) it is sent to
The gate pole of IGBT device one and IGBT device two in circuit is disturbed, to control the open and close of IGBT device one and IGBT device two；
B, the generation of disturbing signal
B1, positive half cycle disturbance
When the original edge voltage of step-down transformer is in positive half cycle, the positive polarity voltage of the secondary side upper end of step-down transformer is by two
The partition of the cathode of pole pipe two and diode four, negative half period disturbance circuit disconnect, do not work；Positive half cycle disturbs circuit work, in which:
Step-down transformer secondary side upper end, diode one, IGBT device one, resistance three and step-down transformer secondary side lower end are successively
It is connected, forms the small resistance branch of positive half cycle；Step-down transformer secondary side upper end, diode three, resistance one, resistance three and downconverter
Device secondary side lower end is sequentially connected, and forms the big resistance branch of positive half cycle；
When the chirping of birds of microprocessor transmission controls signal yP(t)=1 when: the small resistance branch conducting of positive half cycle, positive half cycle are big
Resistance branch is bypassed by the small resistance branch of positive half cycle, and the positive polarity electric current of step-down transformer secondary side upper end flows through the small resistance of positive half cycle
Branch returns to step-down transformer secondary side lower end；
When the chirping of birds of microprocessor transmission controls signal yP(t)=0 when: IGBT device one turns off, the small resistance branch of positive half cycle
Road disconnects, and the positive polarity electric current of step-down transformer secondary side upper end flows through the big resistance branch of positive half cycle and returns under step-down transformer secondary side
End；
The small resistance branch of positive half cycle and the big resistance branch of positive half cycle are in frequency from f0Linear transformation is to f1Chirping of birds control signal
yP(t) forward current is alternately passed through under control, and then frequency is generated in f in tractive power supply system by step-down transformer0It arrives
f1Between positive half cycle disturbance；
B2, negative half period disturbance
When the original edge voltage of step-down transformer is in negative half period, the reverse voltage of step-down transformer secondary side upper end is by two poles
The anode partition of pipe one and diode three, positive half cycle disturbance circuit disconnect, do not work；Negative half period disturbs circuit work, in which:
Step-down transformer secondary side upper end, diode two, IGBT device two, resistance three and step-down transformer secondary side lower end are successively
It is connected, forms the small resistance branch of negative half period；Step-down transformer secondary side upper end, diode four, resistance two, resistance three and downconverter
Device secondary side lower end is sequentially connected, and forms the big resistance branch of negative half period；
When the chirping of birds of microprocessor transmission controls signal yP(t)=1 when: the small resistance branch conducting of negative half period, negative half period are big
Resistance branch is bypassed by the small resistance branch of negative half period, and the negative polarity electric current of step-down transformer secondary side upper end flows through the small resistance of negative half period
Branch returns to step-down transformer secondary side lower end；
When the chirping of birds of microprocessor transmission controls signal yP(t)=0 when: IGBT device two turns off, the small resistance branch of negative half period
Road disconnects, and the negative polarity electric current of step-down transformer secondary side upper end flows through the big resistance branch of negative half period and returns under step-down transformer secondary side
End；
The small resistance branch of negative half period and the big resistance branch of negative half period are in frequency from f0Linear transformation is to f1Chirping of birds control signal
yP(t) negative polarity electric current is alternately passed through under control, and then frequency is generated in f in tractive power supply system by step-down transformer0
To f1Between negative half period disturbance；
C, the acquisition of voltage, current information when disturbing
While disturbing signal generates, voltage sensor is by information of voltage when the disturbance of the tractive power supply system collected
u2(t) microprocessor is sent after handling by signal conditioner；Current sensor is by the disturbance of the tractive power supply system collected
When current information i2(t) after handling by signal conditioner, microprocessor is sent；
D, when undisturbed voltage, current information acquisition
Switch is disconnected, disturbance circuit stops working, and there is no disturbing signals in tractive power supply system；Voltage sensor will be adopted
Information of voltage u when collecting the undisturbed of obtained tractive power supply system1(t), microprocessor is sent after handling by signal conditioner；Electricity
Flow sensor is by current information i when the undisturbed of the tractive power supply system collected1(t), after being handled by signal conditioner
Send microprocessor；
E, frequency domain impedance is obtained
Microprocessor is by information of voltage u when undisturbed1(t), current information i when undisturbed1(t), information of voltage u when disturbing2
(t) current information i when and disturbing2(t), undisturbed time-frequency domain information of voltage U is respectively obtained by Fast Fourier Transform (FFT)1(f)、
Undisturbed time-frequency domain current information I1(f), time-frequency domain information of voltage U is disturbed2(f), time-frequency domain current information I is disturbed2(f)；It counts again
Calculation obtains frequency band (f0~f1) in frequency domain impedance operator Z (f),Wherein f indicates frequency；In turn
Obtain the resonance frequency of tractive power supply system.
Compared with prior art, the utility model has the beneficial effects that
One, the band limits of the disturbing signal of the utility model can voluntarily, arbitrarily be set, and can carry out the width of various frequency ranges
Band impedance measurement, it is adaptable.System can be determined according to the empirical data or historical data of tractive power supply system harmonic characterisitic
System resonance point frequency domain that may be present.When measurement, i.e., using the frequency domain as the setting frequency range of disturbing signal, it can obtain
To the frequency domain impedance and resonance dot frequency of system；Without measuring to the impedance in wide frequency domain, number is measured
It is small according to treating capacity, measurement efficiency is high, the impedance operator measured and accuracy of resonant frequencies are high；Also avoiding measurement, frequency band is narrow causes
Resonance frequency test leakage, the impedance operator measured, resonance frequency are more acurrate, reliable.
Two, in the four disturbance branches disturbed in circuit of the utility model, only there are two branches to need using valuableness
High-power IGBT device, IGBT device usage amount reduce half, and the manufacture of device, maintenance cost are low, make conducive to large-scale promotion
With.
The utility model is described in further detail with reference to the accompanying drawings and detailed description.
Detailed description of the invention
Fig. 1 is the circuit diagram of the device of the utility model embodiment.
Specific embodiment
Fig. 1 is shown, and a kind of specific embodiment of the utility model is, it is a kind of can setting frequency range tractive power supply system frequency
Domain impedance measurement device, the primary coil including meeting the step-down transformer T between contact net C and rail R, step-down transformer T
Secondary winding concatenation switch K be followed by disturb circuit；Current sensor CT is mounted on the primary side of contact net C and step-down transformer T
Between, voltage sensor PT is installed in parallel in the primary side port of step-down transformer T；Current sensor CT, voltage sensor PT with
Signal conditioner SP is connected；Signal conditioner SP is connected with microprocessor MPU；Meanwhile microprocessor MPU also passes through driving circuit
DC is connected with the gate pole of IGBT device in disturbance circuit；
It is characterized by: the disturbance circuit disturbs circuit DT1 by positive half cycle and negative half period disturbance circuit DT2 is formed,
Wherein:
The composition of positive half cycle disturbance circuit DT1 is: the positive phase of the upper end of step-down transformer T secondary side and one D1 of diode
Even；The cathode of one D1 of diode is connected with the collector of one T1 of IGBT device, and the emitter of one T1 of IGBT device passes through resistance one
R1 is connected with the cathode of three D3 of diode；The anode of three D3 of diode is connected with the anode of one D1 of diode；One T1 of IGBT device
Emitter also pass through three R3 of resistance and be connected with the lower end of step-down transformer T secondary side；The gate pole and driving electricity of one T1 of IGBT device
Road DC is connected；
The composition of negative half period disturbance circuit DT2 is: the cathode phase of the upper end of step-down transformer T secondary side and two D2 of diode
Even；The anode of two D2 of diode is connected with the emitter of two T2 of IGBT device, and the collector of two T2 of IGBT device passes through resistance two
R2 is connected with the anode of four D4 of diode；The cathode of four D4 of diode is connected with the cathode of two D2 of diode；Two T2 of IGBT device
Collector also pass through three R3 of resistance and be connected with the lower end of step-down transformer T secondary side；The gate pole and driving electricity of two T2 of IGBT device
Road DC is connected.
A kind of tractive power supply system frequency domain impedance measurement device for setting measurement frequency range using this example, to traction power supply
System carries out the measurement method of frequency domain impedance, the steps include:
A, control signal generates:
Microprocessor MPU generates the chirping of birds signal y (t) of setting frequency range, and the chirping of birds signal y (t) is to change in frequency
In period, the frequency conversion sinusoidal signal that frequency converts linearly over time, mathematic(al) representation are as follows: y (t)=sin (2 π (f0+(f1-f0)
t/Ts) t), wherein t is time, TsFor frequency change period, f0For the lowest frequency value of setting frequency range, f1For setting frequency range
Highest frequency value；Microprocessor MPU obtains frequency from f by frequency conversion sinusoidal signal y (t)0Linear transformation is to f1Chirping of birds control letter
Number yP(t),Chirping of birds is controlled signal by driving circuit DC by closure switch K, microprocessor MPU
yP(t) be sent to disturbance circuit in two T2 of one T1 of IGBT device and IGBT device gate pole, with control one T1 of IGBT device and
The open and close of two T2 of IGBT device；
B, the generation of disturbing signal
B1, positive half cycle disturbance
When the original edge voltage of step-down transformer T is in positive half cycle, the positive polarity voltage quilt of the secondary side upper end of step-down transformer T
The cathode of four D4 of two D2 of diode and diode separates, and negative half period disturbance circuit DT2 disconnects, do not work；Positive half cycle disturbs circuit
DT1 work, in which:
Step-down transformer T secondary side upper end, one D1 of diode, one T1 of IGBT device, three R3 of resistance and step-down transformer T secondary side
Lower end is sequentially connected, and forms the small resistance branch of positive half cycle；Step-down transformer T secondary side upper end, three D3 of diode, one R1 of resistance, electricity
It hinders three R3 and step-down transformer T secondary side lower end is sequentially connected, form the big resistance branch of positive half cycle；
When the chirping of birds of microprocessor MPU transmission controls signal yP(t)=1 when: the small resistance branch conducting of positive half cycle, positive half cycle
Big resistance branch is bypassed by the small resistance branch of positive half cycle, and it is small that the positive polarity electric current of step-down transformer T secondary side upper end flows through positive half cycle
Resistance branch returns to step-down transformer T secondary side lower end；
When the chirping of birds of microprocessor MPU transmission controls signal yP(t)=0 when: one T1 of IGBT device shutdown, the small electricity of positive half cycle
It hinders branch to disconnect, the positive polarity electric current of step-down transformer T secondary side upper end flows through the big resistance branch of positive half cycle and returns to step-down transformer T
Secondary side lower end；
The small resistance branch of positive half cycle and the big resistance branch of positive half cycle are in frequency from f0Linear transformation is to f1Chirping of birds control signal
yP(t) forward current is alternately passed through under control, and then frequency is generated in f in tractive power supply system by step-down transformer T0
To f1Between positive half cycle disturbance；
B2, negative half period disturbance
When the original edge voltage of step-down transformer T is in negative half period, the reverse voltage of step-down transformer T secondary side upper end is by two
The anode partition of three D3 of one D1 of pole pipe and diode, positive half cycle disturbance circuit DT1 disconnect, do not work；Negative half period disturbs circuit DT2
Work, in which:
Step-down transformer T secondary side upper end, two D2 of diode, two T2 of IGBT device, three R3 of resistance and step-down transformer T secondary side
Lower end is sequentially connected, and forms the small resistance branch of negative half period；Step-down transformer T secondary side upper end, four D4 of diode, two R2 of resistance, electricity
It hinders three R3 and step-down transformer T secondary side lower end is sequentially connected, form the big resistance branch of negative half period；
When the chirping of birds of microprocessor MPU transmission controls signal yP(t)=1 when: the small resistance branch conducting of negative half period, negative half period
Big resistance branch is bypassed by the small resistance branch of negative half period, and it is small that the negative polarity electric current of step-down transformer T secondary side upper end flows through negative half period
Resistance branch returns to step-down transformer T secondary side lower end；
When the chirping of birds of microprocessor MPU transmission controls signal yP(t)=0 when: two T2 of IGBT device shutdown, the small electricity of negative half period
It hinders branch to disconnect, the negative polarity electric current of step-down transformer T secondary side upper end flows through the big resistance branch of negative half period and returns to step-down transformer T
Secondary side lower end；
The small resistance branch of negative half period and the big resistance branch of negative half period are in frequency from f0Linear transformation is to f1Chirping of birds control signal
yP(t) negative polarity electric current is alternately passed through under control, and then frequency is generated in tractive power supply system by step-down transformer T and is existed
f0To f1Between negative half period disturbance；
C, the acquisition of voltage, current information when disturbing
While disturbing signal generates, voltage sensor PT believes voltage when the disturbance of the tractive power supply system collected
Cease u2(t) microprocessor MPU is sent after handling by signal conditioner SP；The traction power supply system that current sensor CT will be collected
Current information i when the disturbance of system2(t) after handling by signal conditioner SP, microprocessor MPU is sent；
D, when undisturbed voltage, current information acquisition
Switch K is disconnected, disturbance circuit stops working, and there is no disturbing signals in tractive power supply system；Voltage sensor PT
By information of voltage u when the undisturbed of the tractive power supply system collected1(t), micro- place is sent after handling by signal conditioner SP
Manage device MPU；Current sensor CT is by current information i when the undisturbed of the tractive power supply system collected1(t), pass through signal
Microprocessor MPU is sent after conditioner SP processing；
E, frequency domain impedance is obtained
Microprocessor MPU is by information of voltage u when undisturbed1(t), current information i when undisturbed1(t), voltage is believed when disturbing
Cease u2(t) current information i when and disturbing2(t), undisturbed time-frequency domain information of voltage U is respectively obtained by Fast Fourier Transform (FFT)1
(f), undisturbed time-frequency domain current information I1(f), time-frequency domain information of voltage U is disturbed2(f), time-frequency domain current information I is disturbed2(f)；
Frequency band (f is calculated again0~f1) in frequency domain impedance operator Z (f),Wherein f indicates frequency；
And then obtain the resonance frequency of tractive power supply system.
Claims (1)
1. one kind can setting frequency range tractive power supply system frequency domain impedance measurement device, including connect in contact net (C) and rail (R)
Between step-down transformer (T) primary coil, step-down transformer (T) secondary winding concatenation switch (K) be followed by disturbance circuit；
Current sensor (CT) is mounted between contact net (C) and the primary side of step-down transformer (T), and voltage sensor (PT) is installed in parallel
In the primary side port of step-down transformer (T)；Current sensor (CT), voltage sensor (PT) are connected with signal conditioner (SP)；
Signal conditioner (SP) is connected with microprocessor (MPU)；Meanwhile microprocessor (MPU) also passes through driving circuit (DC) and disturbance
The gate pole of IGBT device is connected in circuit；
It is characterized by: the disturbance circuit is made of positive half cycle disturbance circuit (DT1) and negative half period disturbance circuit (DT2),
Wherein:
The composition of positive half cycle disturbance circuit (DT1) is: the upper end of step-down transformer (T) secondary side and the positive phase of diode one (D1)
Even；The cathode of diode one (D1) is connected with the collector of IGBT device one (T1), and the emitter of IGBT device one (T1) passes through
Resistance one (R1) is connected with the cathode of diode three (D3)；The positive phase of the anode and diode one (D1) of diode three (D3)
Even；The emitter of IGBT device one (T1) also passes through resistance three (R3) and is connected with the lower end of step-down transformer (T) secondary side；IGBT device
The gate pole of part one (T1) is connected with driving circuit (DC)；
The composition of negative half period disturbance circuit (DT2) is: the upper end of step-down transformer (T) secondary side and the cathode phase of diode two (D2)
Even；The anode of diode two (D2) is connected with the emitter of IGBT device two (T2), and the collector of IGBT device two (T2) passes through
Resistance two (R2) is connected with the anode of diode four (D4)；The cathode phase of the cathode of diode four (D4) and diode two (D2)
Even；The collector of IGBT device two (T2) also passes through resistance three (R3) and is connected with the lower end of step-down transformer (T) secondary side；IGBT device
The gate pole of part two (T2) is connected with driving circuit (DC).
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| CN201821103175.5U CN208636375U (en) | 2018-07-12 | 2018-07-12 | It is a kind of can setting frequency range tractive power supply system frequency domain impedance measurement device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109030946A (en) * | 2018-07-12 | 2018-12-18 | 西南交通大学 | Can setting frequency range tractive power supply system frequency domain impedance measurement device and measurement method |
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2018
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109030946A (en) * | 2018-07-12 | 2018-12-18 | 西南交通大学 | Can setting frequency range tractive power supply system frequency domain impedance measurement device and measurement method |
| CN109030946B (en) * | 2018-07-12 | 2023-10-20 | 西南交通大学 | Traction power supply system frequency domain impedance measurement method capable of setting frequency band |
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