CN109696579A - A kind of voltage detecting circuit and its detection method for flame-proof type charger - Google Patents
A kind of voltage detecting circuit and its detection method for flame-proof type charger Download PDFInfo
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- CN109696579A CN109696579A CN201910167623.0A CN201910167623A CN109696579A CN 109696579 A CN109696579 A CN 109696579A CN 201910167623 A CN201910167623 A CN 201910167623A CN 109696579 A CN109696579 A CN 109696579A
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- voltage
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- cyclical fluctuations
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
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- General Physics & Mathematics (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a kind of voltage detecting circuits for flame-proof type charger, it is separately mounted to the voltage detection module of charger output end and lithium battery charging end, voltage fluctuation acquisition module is connected in the voltage detection module of charger output end, for acquiring the curve of cyclical fluctuations of charging voltage；Voltage detection module and voltage fluctuation acquisition module are connect with the input terminal of controller respectively, and controller is analyzed by the magnitude of a voltage fluctuation to charging voltage value and charger output end, obtain the real-time status of lithium battery charging.The present invention can improve the deficiencies in the prior art, improve the accuracy for lithium battery charging detection.
Description
Technical field
The present invention relates to lithium battery charging technique field, especially a kind of voltage detecting circuit for flame-proof type charger
And its detection method.
Background technique
Due to the safe and reliable and ease of use of lithium battery, underground coal mine vehicle generallys use the supplier of electricity of lithium battery
Formula.Lithium battery is being carried out, in order to protect battery, needing to be measured in real time charging voltage in charging process, is being sentenced with this
Whether normal determine charging process.Existing detection method is usually that detection device is directly installed on lithium battery, by measuring lithium
The real-time voltage of battery is determined.This mode not can avoid influence of the external interference to lithium battery voltage in charging process,
Cause to be easy to appear erroneous judgement.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of voltage detecting circuit for flame-proof type charger and its inspections
Survey method is able to solve the deficiencies in the prior art, improves the accuracy for lithium battery charging detection.
In order to solve the above technical problems, the technical solution used in the present invention is as follows.
A kind of voltage detecting circuit for flame-proof type charger, including,
It is separately mounted to the voltage detection module of charger output end and lithium battery charging end,
Voltage fluctuation acquisition module is connected in the voltage detection module of charger output end, for acquiring charging electricity
The curve of cyclical fluctuations of pressure；
Voltage detection module and voltage fluctuation acquisition module are connect with the input terminal of controller respectively, and controller is by filling
The magnitude of a voltage fluctuation of piezoelectric voltage value and charger output end is analyzed, and the real-time status of lithium battery charging is obtained.
Preferably, voltage detection module includes voltage sensor, the output end of voltage sensor, voltage sensor passes through
First resistor connects the normal phase input end of the first amplifier, and the inverting input terminal of the first amplifier is grounded by second resistance, the first fortune
The inverting input terminal put is connected to the output end of the first amplifier by 3rd resistor, and the output end of the first amplifier is as voltage detecting
The output end of module.
Preferably, the input terminal of voltage fluctuation acquisition module is connected to the output end of voltage sensor, voltage fluctuation is adopted
The input terminal of collection module is connected to the inverting input terminal of the second amplifier, the positive of the second amplifier by the 4th resistance and the 5th resistance
Input terminal is grounded between the 4th resistance and the 5th resistance by first capacitor, the 4th resistance and the 5th by the 6th resistance eutral grounding
Resistance is connected to the output end of the second amplifier by the 7th resistance, and the inverting input terminal of the second amplifier passes through the second capacitance connection extremely
The output end of the output end of second amplifier, the second amplifier passes through collector of the third capacitance connection to triode, the base of triode
Pole is connected to the collector of triode by the 8th resistance, and the emitter of triode passes through the 4th capacity earth.
A kind of detection method of the above-mentioned voltage detecting circuit for flame-proof type charger, comprising the following steps:
A, the detection signal of controller difference collection voltages detection module and voltage fluctuation acquisition module；
B, the voltage signal meter for the charger output end and lithium battery charging end that controller is detected according to voltage detection module
Calculate the first charging voltage curve of cyclical fluctuations；
C, controller calculates the second charging voltage curve of cyclical fluctuations according to the detection signal of voltage fluctuation acquisition module；
D, the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations are compared controller, if first fills
The similarity of the piezoelectric voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations is more than threshold value, then is judged to charging normal, otherwise sentence
It is abnormal to be set to charging.
Preferably, being carried out respectively to the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations in step D
Fourier decomposition carries out similarity comparison to the signal component of each frequency range respectively, and assigns weight to the similarity of each frequency range
Value, the weighted value of frequency range are inversely proportional with its centre frequency, obtain the first charging by the weighted average calculation of each frequency range similarity
The similarity of voltage fluctuation curve and the second charging voltage curve of cyclical fluctuations.
Preferably, marking indicatrix in each frequency band signals component of the first charging voltage curve of cyclical fluctuations in step B
Section, labeling method is,
B1, Fourier decomposition is carried out to the first charging voltage curve of cyclical fluctuations, finding in signal component has periodically, and
Frequency is lower than the waving interval of this signal component；
B2, the signal component curved section of the waving interval two sides searched out in step B1 is labeled as indicatrix section, wave
The sum of the time shaft length of indicatrix section of dynamic section two sides is equal to the time shaft length of waving interval.
Preferably, Fourier decomposition is carried out to the second charging voltage curve of cyclical fluctuations in step C, according to the first charging electricity
Press the curve of cyclical fluctuations in mark indicatrix section, traverse the second charging voltage curve of cyclical fluctuations, under similar frequency bands with indicatrix
The linearly related part of section is marked.
Preferably, in step D, if the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations are the same as in frequency range
The fairly linear correlation of indicatrix section of signal component, then be determined as 100% for the similarity of this frequency range.
Brought beneficial effect is by adopting the above technical scheme: the present invention passes through to charger output end and lithium battery
The voltage of charging end synchronizes detection, then calculates voltage fluctuation curve.Using to different detection position voltage fluctuation curves
Comparison, realize and exclude influence of the external interference for voltage fluctuation.In comparison process, by voltage fluctuation curve frequency-division section
It decomposes, realizes and the independence of different frequency range is compared.By the label to indicatrix section, can be reduced in comparison process non-
Necessary operation improves and compares speed, while reducing influence of the random disturbances for comparison process.
Detailed description of the invention
Fig. 1 is the schematic diagram of a specific embodiment of the invention.
Fig. 2 is the circuit diagram of voltage detection module in a specific embodiment of the invention.
Fig. 3 is the circuit diagram of voltage fluctuation acquisition module in a specific embodiment of the invention.
Specific embodiment
Referring to Fig.1-3, the present invention includes,
It is separately mounted to the voltage detection module 1 of charger output end and lithium battery charging end,
It is connected with voltage fluctuation acquisition module 2 in the voltage detection module 1 of charger output end, for acquiring charging
The curve of cyclical fluctuations of voltage；
Voltage detection module 1 and voltage fluctuation acquisition module 2 are connect with the input terminal of controller 3 respectively, and controller 3 passes through
The magnitude of a voltage fluctuation of charging voltage value and charger output end is analyzed, the real-time status of lithium battery charging is obtained.
Voltage detection module 1 includes voltage sensor 4, and the output end of voltage sensor 4, voltage sensor 4 passes through first
The normal phase input end of resistance R1 the first amplifier of connection A1, the inverting input terminal of the first amplifier A1 are grounded by second resistance R2, the
The inverting input terminal of one amplifier A1 is connected to the output end of the first amplifier A1, the output end of the first amplifier A1 by 3rd resistor R3
Output end as voltage detection module 1.
The input terminal of voltage fluctuation acquisition module 2 is connected to the output end of voltage sensor 4, voltage fluctuation acquisition module 2
Input terminal the inverting input terminal of the second amplifier A2 is connected to by the 4th resistance R4 and the 5th resistance R5, the second amplifier A2 is just
Phase input terminal is grounded by the 6th resistance R6, is grounded between the 4th resistance R4 and the 5th resistance R5 by first capacitor C1, the 4th
Resistance R4 and the 5th resistance R5 is connected to the output end of the second amplifier A2, the anti-phase input of the second amplifier A2 by the 7th resistance R7
End is connected to the output end of the second amplifier A2 by the second capacitor C2, and the output end of the second amplifier A2 passes through third capacitor C3 connection
To the collector of triode Q, the base stage of triode Q is connected to the collector of triode Q by the 8th resistance R8, triode Q's
Emitter is grounded by the 4th capacitor C4.
In addition, the base stage of triode Q is connected to Continuity signal input terminal VCC by the 9th resistance R9.
In the present invention, first resistor R1 is 2.5k Ω, second resistance R2 is 4k Ω, 3rd resistor R3 is 1k Ω, the 4th electricity
Resistance R4 is 5.5k Ω, the 5th resistance R5 is 3.5k Ω, the 6th resistance R6 is 10k Ω, the 7th resistance R7 is 0.75k Ω, the 8th electricity
Resistance R8 is 6k Ω, the 9th resistance R9 is 4.5k Ω.First capacitor C1 is 350 μ F, the second capacitor C2 is 700 μ F, third capacitor C3
It is 150 μ F for 500 μ F, the 4th capacitor C4.
A kind of detection method of the above-mentioned voltage detecting circuit for flame-proof type charger, comprising the following steps:
A, controller 3 distinguishes the detection signal of collection voltages detection module 1 and voltage fluctuation acquisition module 2；
B, the voltage signal for the charger output end and lithium battery charging end that controller 3 is detected according to voltage detection module 1
Calculate the first charging voltage curve of cyclical fluctuations；
C, controller 3 calculates the second charging voltage curve of cyclical fluctuations according to the detection signal of voltage fluctuation acquisition module 2；
D, the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations are compared controller 3, if first
The similarity of the charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations is more than threshold value, then is judged to charging normal, otherwise
It is determined as the exception that charges.
In step D, Fourier point is carried out to the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations respectively
Solution carries out similarity comparison to the signal component of each frequency range respectively, and assigns weighted value to the similarity of each frequency range, frequency range
Weighted value is inversely proportional with its centre frequency, and it is bent to obtain the fluctuation of the first charging voltage by the weighted average calculation of each frequency range similarity
The similarity of line and the second charging voltage curve of cyclical fluctuations.
In step B, indicatrix section, label side are marked in each frequency band signals component of the first charging voltage curve of cyclical fluctuations
Method is,
B1, Fourier decomposition is carried out to the first charging voltage curve of cyclical fluctuations, finding in signal component has periodically, and
Frequency is lower than the waving interval of this signal component；
B2, the signal component curved section of the waving interval two sides searched out in step B1 is labeled as indicatrix section, wave
The sum of the time shaft length of indicatrix section of dynamic section two sides is equal to the time shaft length of waving interval.
In step C, Fourier decomposition is carried out to the second charging voltage curve of cyclical fluctuations, according to the first charging voltage curve of cyclical fluctuations
Middle label indicatrix section traverses the second charging voltage curve of cyclical fluctuations, to linearly related with indicatrix section under similar frequency bands
Part be marked.
In step D, if the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations are the same as signal component in frequency range
The fairly linear correlation of indicatrix section, then the similarity of this frequency range is determined as 100%.
In addition, in the detection process, periodically being led by Continuity signal input terminal VCC to the sending of the base stage of triode Q
Messenger.Change the filtering parameter of voltage fluctuation acquisition module 2 using triode ON is forced, and then this change is reflected
To the signal component of corresponding frequency band.In marker characteristic curved section, calculates the signal fluctuation embodied in signal component and lead
The phase deviation of pass signal input VCC uses this phase deviation as correction amount, carries out to the second charging voltage curve of cyclical fluctuations
Phase only pupil filter.By carrying out phase only pupil filter, the first charging voltage curve of cyclical fluctuations and the second charging voltage wave can be further improved
Synchronism of the moving curve in comparison process improves comparison accuracy.
In the description of the present invention, it is to be understood that, term " longitudinal direction ", " transverse direction ", "upper", "lower", "front", "rear",
The orientation or positional relationship of the instructions such as "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outside" is based on attached drawing institute
The orientation or positional relationship shown is merely for convenience of the description present invention, rather than the device or element of indication or suggestion meaning must
There must be specific orientation, be constructed and operated in a specific orientation, therefore be not considered as limiting the invention.
The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent thereof.
Claims (8)
1. a kind of voltage detecting circuit for flame-proof type charger, it is characterised in that: including,
It is separately mounted to the voltage detection module (1) of charger output end and lithium battery charging end,
Voltage fluctuation acquisition module (2) are connected in the voltage detection module (1) of charger output end, for acquiring charging
The curve of cyclical fluctuations of voltage；
Voltage detection module (1) and voltage fluctuation acquisition module (2) are connect with the input terminal of controller (3) respectively, controller (3)
It is analyzed by the magnitude of a voltage fluctuation to charging voltage value and charger output end, obtains the real-time status of lithium battery charging.
2. the voltage detecting circuit according to claim 1 for flame-proof type charger, it is characterised in that: the voltage inspection
Surveying module (1) includes voltage sensor (4), and the output end of voltage sensor (4), voltage sensor (4) passes through first resistor
(R1) normal phase input end of the first amplifier (A1) is connected, the inverting input terminal of the first amplifier (A1) is connect by second resistance (R2)
Ground, the inverting input terminal of the first amplifier (A1) are connected to the output end of the first amplifier (A1), the first fortune by 3rd resistor (R3)
Put output end of the output end of (A1) as voltage detection module (1).
3. the voltage detecting circuit according to claim 2 for flame-proof type charger, it is characterised in that: the voltage wave
The input terminal of dynamic acquisition module (2) is connected to the output end of voltage sensor (4), the input terminal of voltage fluctuation acquisition module (2)
The inverting input terminal of the second amplifier (A2) is connected to by the 4th resistance (R4) and the 5th resistance (R5), the second amplifier (A2) is just
Phase input terminal is grounded by the 6th resistance (R6), is connect between the 4th resistance (R4) and the 5th resistance (R5) by first capacitor (C1)
Ground, the 4th resistance (R4) and the 5th resistance (R5) are connected to the output end of the second amplifier (A2) by the 7th resistance (R7), and second
The inverting input terminal of amplifier (A2) is connected to the output end of the second amplifier (A2) by the second capacitor (C2), the second amplifier (A2)
Output end is connected to the collector of triode (Q) by third capacitor (C3), and the base stage of triode (Q) passes through the 8th resistance (R8)
It is connected to the collector of triode (Q), the emitter of triode (Q) is grounded by the 4th capacitor (C4).
4. the detection method described in a kind of claim 1-3 any one for the voltage detecting circuit of flame-proof type charger,
Characterized by the following steps:
A, the detection signal of controller (3) difference collection voltages detection module (1) and voltage fluctuation acquisition module (2)；
B, the voltage signal for the charger output end and lithium battery charging end that controller (3) is detected according to voltage detection module (1)
Calculate the first charging voltage curve of cyclical fluctuations；
C, controller (3) calculates the second charging voltage curve of cyclical fluctuations according to the detection signal of voltage fluctuation acquisition module (2)；
D, the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations are compared controller (3), if first fills
The similarity of the piezoelectric voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations is more than threshold value, then is judged to charging normal, otherwise sentence
It is abnormal to be set to charging.
5. the detection method of the voltage detecting circuit according to claim 4 for flame-proof type charger, it is characterised in that:
In step D, Fourier decomposition is carried out to the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations respectively, it is right respectively
The signal component of each frequency range carries out similarity comparison, and assigns weighted value to the similarity of each frequency range, the weighted value of frequency range with
Its centre frequency is inversely proportional, and obtains the first charging voltage curve of cyclical fluctuations and second by the weighted average calculation of each frequency range similarity
The similarity of the charging voltage curve of cyclical fluctuations.
6. the detection method of the voltage detecting circuit according to claim 5 for flame-proof type charger, it is characterised in that:
In step B, label indicatrix section, labeling method are in each frequency band signals component of the first charging voltage curve of cyclical fluctuations,
B1, Fourier decomposition is carried out to the first charging voltage curve of cyclical fluctuations, finding in signal component has periodically, and frequency
Lower than the waving interval of this signal component；
B2, the signal component curved section of the waving interval two sides searched out in step B1 is labeled as indicatrix section, wave zone
Between the sum of the time shaft lengths of indicatrix section of two sides be equal to the time shaft length of waving interval.
7. the detection method of the voltage detecting circuit according to claim 6 for flame-proof type charger, it is characterised in that:
In step C, Fourier decomposition is carried out to the second charging voltage curve of cyclical fluctuations, it is special according to being marked in the first charging voltage curve of cyclical fluctuations
Levy curved section, traverse the second charging voltage curve of cyclical fluctuations, under similar frequency bands with the part of indicatrix section linear correlation into
Line flag.
8. the detection method of the voltage detecting circuit according to claim 7 for flame-proof type charger, it is characterised in that:
In step D, if the first charging voltage curve of cyclical fluctuations and the second charging voltage curve of cyclical fluctuations are bent with the feature of signal component in frequency range
The fairly linear correlation of line segment, then be determined as 100% for the similarity of this frequency range.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201910167623.0A CN109696579A (en) | 2019-03-06 | 2019-03-06 | A kind of voltage detecting circuit and its detection method for flame-proof type charger |
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| CN201910167623.0A CN109696579A (en) | 2019-03-06 | 2019-03-06 | A kind of voltage detecting circuit and its detection method for flame-proof type charger |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105044418A (en) * | 2015-08-09 | 2015-11-11 | 安徽普为智能科技有限责任公司 | DC charging pile charging metering method |
| CN105490344A (en) * | 2016-01-05 | 2016-04-13 | 深圳市金霆正通科技有限公司 | Charging current control method and control system of electromobile |
| CN106057211A (en) * | 2016-05-27 | 2016-10-26 | 广州多益网络股份有限公司 | Signal matching method and device |
| CN106938618A (en) * | 2017-04-11 | 2017-07-11 | 绵阳旭立辰科技有限公司 | The method that early warning is carried out using the electric vehicle battery charger system for possessing warning function |
| CN107037246A (en) * | 2017-05-17 | 2017-08-11 | 栗春侠 | A kind of universal charging station charge metering device and its metering method |
| CN207924003U (en) * | 2018-04-04 | 2018-09-28 | 河南华拓电力设备有限公司 | Wisdom safety utilization of electric power monitoring detector voltage display device |
-
2019
- 2019-03-06 CN CN201910167623.0A patent/CN109696579A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105044418A (en) * | 2015-08-09 | 2015-11-11 | 安徽普为智能科技有限责任公司 | DC charging pile charging metering method |
| CN105490344A (en) * | 2016-01-05 | 2016-04-13 | 深圳市金霆正通科技有限公司 | Charging current control method and control system of electromobile |
| CN106057211A (en) * | 2016-05-27 | 2016-10-26 | 广州多益网络股份有限公司 | Signal matching method and device |
| CN106938618A (en) * | 2017-04-11 | 2017-07-11 | 绵阳旭立辰科技有限公司 | The method that early warning is carried out using the electric vehicle battery charger system for possessing warning function |
| CN107037246A (en) * | 2017-05-17 | 2017-08-11 | 栗春侠 | A kind of universal charging station charge metering device and its metering method |
| CN207924003U (en) * | 2018-04-04 | 2018-09-28 | 河南华拓电力设备有限公司 | Wisdom safety utilization of electric power monitoring detector voltage display device |
Non-Patent Citations (2)
| Title |
|---|
| 薛军 等: "一种通过电压特征区分台区和相别的方法研究", 《2017智能电网新技术发展与应用研讨会论文集》 * |
| 钟建林 等: "基于波形相似度的容差模拟电路软故障诊断", 《电工技术学报》 * |
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Application publication date: 20190430 |