CN107015167A - A kind of Switching Power Supply ripple voltage detection method based on detection techniques - Google Patents
A kind of Switching Power Supply ripple voltage detection method based on detection techniques Download PDFInfo
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- CN107015167A CN107015167A CN201611256672.4A CN201611256672A CN107015167A CN 107015167 A CN107015167 A CN 107015167A CN 201611256672 A CN201611256672 A CN 201611256672A CN 107015167 A CN107015167 A CN 107015167A
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- power supply
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/40—Testing power supplies
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Abstract
The present invention relates to a kind of Switching Power Supply ripple voltage detection method based on detection techniques, its technical characterstic is：Comprise the following steps：Step 1, voltage waveform is carried out to the output voltage of Switching Power Supply by hardware circuit adjusted；Step 2, the resonance principle according to RLC high q-factor circuits, design three detecting circuits, calculate the concussion frequency and amplitude of ripple alternating voltage in the output voltage of Switching Power Supply after the voltage magnitude for measuring three detecting circuits, and then the failure that the electrochemical capacitor and oscillator to Switching Power Supply occur is alarmed.The output voltage of the Switching Power Supply of the present invention is adjusted by hardware circuit, and the ripple alternating voltage in the DC voltage of Switching Power Supply is filtered and amplified, then ripple alternating current voltage frequency and amplitude are monitored with detecting circuit.Ripple alternating voltage has reacted the working condition of Switching Power Supply, by that can carry out advanced warning to Switching Power Supply failure to the detection of ripple alternating voltage.
Description
Technical field
The invention belongs to facility switching power technology field, it is related to secondary device Condition-Based Maintenance Technology, especially a kind of base
In the Switching Power Supply ripple voltage detection method of detection techniques.
Background technology
Switching Power Supply is to utilize modern power electronics technology, the time ratio of controlling switch transistor ON and shut-off, dimension
A kind of power supply of regulated output voltage is held, Switching Power Supply is typically made up of pulse width modulation (PWM) control IC and MOSFET.By
There is high conversion efficiency, small volume in Switching Power Supply and lightweight be widely used.
But due to the influence of ripple and noise that Switching Power Supply is led to, cause Switching Power Supply output is not pure direct current
Pressure, the inside includes alternating component.Ripple is the fluctuation that Switching Power Supply exports DC voltage, its switch motion with Switching Power Supply
It is relevant.Each open and close process, forms the process of a charging and discharging, so that the fluctuation of output voltage is caused, output electricity
The vibration frequency of pressure is identical with the frequency switched.
The ripple voltage of Switching Power Supply refers to the peak-to-peak value between the crest of ripple and trough, is that a kind of complicated high frequency is small
Amplitude voltage, its size is relevant with the capacity and quality of the input and output capacitors of Switching Power Supply.And existing switch electricity
Source ripple voltage detection method is that the output voltage of Switching Power Supply is sampled by high frequency AD, utilizes central processing unit CUP
Data to sampling are calculated, and ripple voltage amplitude is calculated by complicated Fourier algorithm, when ripple voltage is higher than one
Alarm is sent during tentering value.
It follows that Switching Power Supply ripple voltage detection method of the prior art needs high-frequency AD samplings could be right
Ripple waveform has preferable collection, has very high requirement to AD samplings, moreover, central processor CPU is needed by complicated Fu
In leaf algorithm calculate ripple voltage amplitude, add the burden of central processor CPU.
The content of the invention
It is an object of the invention to overcome the deficiencies of the prior art and provide a kind of reasonable in design, convenient and practical, algorithm is simple
And the Switching Power Supply ripple voltage detection method based on detection techniques with warning function.
The present invention solves its technical problem and takes following technical scheme to realize：
A kind of Switching Power Supply ripple voltage detection method based on detection techniques, comprises the following steps：
Step 1, voltage waveform is carried out to the output voltage of Switching Power Supply by hardware circuit adjusted；
Step 2, the resonance principle according to RLC high q-factor circuits, design three detecting circuits, measure three detecting circuits
Voltage magnitude after calculate the concussion frequency and amplitude of ripple alternating voltage in the output voltage of Switching Power Supply, and then to switch
The failure that the electrochemical capacitor and oscillator of power supply occur is alarmed.
Moreover, the specific method of the step 1 is：By transistor amplifier to line in the output voltage of Switching Power Supply
Alternating current wave is pressed greatly, is then filtered the flip-flop in switch power source output voltage by RC filter circuits.
Moreover, the specific steps of the step 2 include：
(1) 3 Q value identical detecting circuits are designed, its tuned frequency is respectively W0, W1 and W2, wherein, W0-W1=W2-
W0；
In above formula, W0 is frequency when Switching Power Supply is normally run, and W1 is Switching Power Supply failure warning frequency, and W2 is to examine
Channel frequency；
(2) according to the capacitance characteristic of Switching Power Supply, the police of ripple alternating voltage in the output voltage of Switching Power Supply is calculated
Show amplitude IR++；
(3) voltage magnitude for measuring three detecting circuits is respectively IR0, IR1 and IR2, and calculated according to equation below
The concussion frequency Wk of ripple alternating voltage in the output voltage of Switching Power Supply；
(1+jQ (W0/Wk-Wk/W0))/(1+jQ (W1/Wk-Wk/W1))=IR1/IR0
In above formula, j is that imaginary number j square is Q values that -1, Q is High " Q " Circuit；
(4) according to the concussion frequency Wk of ripple alternating voltage in the output voltage of Switching Power Supply, calculated using equation below
Go out the voltage magnitude IRk of ripple alternating voltage in the output voltage of Switching Power Supply；
IRk=(1+jQ (W0/Wk-Wk/W0)) IR0
(5) the concussion frequency Wk and Switching Power Supply failure warning of ripple alternating voltage in the output voltage of Switching Power Supply are compared
Frequency W1 size, if Wk<W1, then judge that Switching Power Supply oscillator goes wrong；
(6) voltage magnitude IRk and the output of Switching Power Supply of ripple alternating voltage in the output voltage of Switching Power Supply are compared
The warning amplitude IR++ of ripple alternating voltage size in voltage, if IRk>IR++, then judge that Switching Power Supply electrolysis electric capacity goes out
Existing problem.
Advantages and positive effects of the present invention are：
1st, the output voltage of Switching Power Supply of the invention is adjusted by hardware circuit, by the DC voltage of Switching Power Supply
The filtering amplification of ripple alternating voltage, is then monitored with detecting circuit to ripple alternating current voltage frequency and amplitude.Ripple is exchanged
The voltage response working condition of facility switching power supply, by can to facility switching power supply failure to the detection of ripple alternating voltage
Carry out advanced warning.
2nd, the present invention is adjusted by hardware circuit to switch power source output voltage, detection is amplified, can be to CPU processor
The requirement reduction of AD sample frequencys, CPU programs waveform algorithm will be greatly simplified, and alleviate CPU burden, make CPU operations more
It is stable.
3rd, pass filter amplifying circuit and detecting circuit of the present invention produce single waveform voltage to the reduction of AD sampling requests, and only
Ripple alternating voltage amplitude need to be carried out to single waveform voltage to calculate, the reduction of algorithm difficulty.
Brief description of the drawings
Fig. 1 is flow chart of the method for the present invention；
Fig. 2 be the fixed frequency of the present invention for W0 high q-factor circuit to the response curves of different driving voltages.
Embodiment
The embodiment of the present invention is described in further detail below in conjunction with accompanying drawing：
The present invention has researched and proposed a kind of Switching Power Supply ripple voltage detection method based on detection techniques, Switching Power Supply
Output voltage is adjusted by hardware circuit, and the ripple alternating voltage in DC voltage is filtered and amplified, then with detecting circuit pair
Ripple alternating current voltage frequency and amplitude are monitored.Ripple alternating voltage has reacted the working condition of device Switching Power Supply, passes through
Advanced warning can be carried out to device Switching Power Supply failure to the detection of ripple alternating voltage.
A kind of Switching Power Supply ripple voltage detection method based on detection techniques, as shown in figure 1, comprising the following steps：
Step 1, voltage waveform is carried out to the output voltage of Switching Power Supply by hardware circuit adjusted；
The specific method of the step 1 is：The ripple in switch power source output voltage is handed over by transistor amplifier
Voltage amplification is flowed, then the flip-flop in switch power source output voltage is filtered by RC filter circuits.
Ripple alternating voltage is mainly high-frequency ac voltage in the output voltage of Switching Power Supply, the electricity of the ripple alternating voltage
Pressure amplitude value very little, is the high-frequency ac voltage of MV ranks, therefore, and the ripple alternating voltage in the output voltage of Switching Power Supply needs
Amplification could carry out signal acquisition.In the present embodiment, ripple alternating voltage can be amplified by transistor amplifier, RC
Filter circuit is logical exchange resistance DC circuit, because the present invention only needs to analyze the ripple alternating voltage of Switching Power Supply,
So unwanted direct voltage component in the output voltage of Switching Power Supply is filtered out.
Step 2, the resonance principle according to RLC high q-factor circuits, design three detecting circuits, measure three detecting circuits
Voltage magnitude after calculate the concussion frequency and amplitude of ripple alternating voltage in the output voltage of Switching Power Supply, and then to switch
The failure that the electrochemical capacitor and oscillator of power supply occur is alarmed.
Wherein, detection is exactly that its operation principle is the resonance of RLC high q-factor circuits by the waveform amplification of a specific frequency
Principle.As shown in Fig. 2 the tuned frequency of rlc circuit is W0, the driving voltage of identical amplitude different frequency, the peak value electricity of response
Pressure is most of to be fallen near W0, therefore detecting circuit can be amplified to the voltage of a frequency.
The response pattern of the circuit of identical Q values is similar, and when the tuned frequency of rlc circuit is W1, its circuit is to swashing
It is Fig. 2 curves to left W0-W1 to encourage the response curve of voltage.Switching Power Supply ripple can be calculated by step 2 according to translation to hand over
Flow the frequency and amplitude of voltage.
The specific steps of the step 2 include：
(1) 3 Q value identical detecting circuits are designed, its tuned frequency is respectively W0, W1 and W2, wherein, W0-W1=W2-
W0；
In above formula, W0 is frequency when Switching Power Supply is normally run, and W1 is Switching Power Supply failure warning frequency, and W2 is to examine
Channel frequency；
(2) according to the capacitance characteristic of Switching Power Supply, the police of ripple alternating voltage in the output voltage of Switching Power Supply is calculated
Show amplitude IR++；
(3) voltage magnitude for measuring three detecting circuits is respectively IR0, IR1 and IR2, and calculated according to equation below
The concussion frequency Wk of ripple alternating voltage in the output voltage of Switching Power Supply；
(1+jQ (W0/Wk-Wk/W0))/(1+jQ (W1/Wk-Wk/W1))=IR1/IR0
In above formula, j is that imaginary number j square is Q values that -1, Q is High " Q " Circuit；
(4) according to the concussion frequency Wk of ripple alternating voltage in the output voltage of Switching Power Supply, calculated using equation below
Go out the voltage magnitude IRk of ripple alternating voltage in the output voltage of Switching Power Supply；
IRk=(1+jQ (W0/Wk-Wk/W0)) IR0
(5) the concussion frequency Wk and Switching Power Supply failure warning of ripple alternating voltage in the output voltage of Switching Power Supply are compared
Frequency W1 size, if Wk<W1, then judge that Switching Power Supply oscillator goes wrong；
(6) voltage magnitude IRk and the output of Switching Power Supply of ripple alternating voltage in the output voltage of Switching Power Supply are compared
The warning amplitude IR++ of ripple alternating voltage size in voltage, if IRk>IR++, then judge that Switching Power Supply electrolysis electric capacity goes out
Existing problem.
Because the frequency of ripple alternating voltage in the output voltage of Switching Power Supply is relevant with the frequency of oscillation of Switching Power Supply, adopt
The voltage of fixed frequency can be amplified with detecting circuit, collection, which calculates detecting circuit voltage magnitude, can calculate the width of ripple voltage
Value, and then electrochemical capacitor is detected.Overcoming traditional AD samplings needs high frequency sampling and CPU just to enter by complicated algorithm
The shortcoming that traveling wave line alternating voltage amplitude is calculated.
After patent achievement application, detection process is carried out to ripple voltage by hardware circuit, it is possible to decrease power detecting loop
Cost, using low cost CPU become possibility, power supply ripple voltage detecting application is more extensive.
It is emphasized that embodiment of the present invention is illustrative, rather than it is limited, therefore present invention bag
Include and be not limited to embodiment described in embodiment, it is every by those skilled in the art's technique according to the invention scheme
The other embodiment drawn, also belongs to the scope of protection of the invention.
Claims (3)
1. a kind of Switching Power Supply ripple voltage detection method based on detection techniques, it is characterised in that：Comprise the following steps：
Step 1, voltage waveform is carried out to the output voltage of Switching Power Supply by hardware circuit adjusted；
Step 2, the resonance principle according to RLC high q-factor circuits, design three detecting circuits, measure the electricity of three detecting circuits
The concussion frequency and amplitude of ripple alternating voltage in the output voltage of Switching Power Supply are calculated after pressure amplitude value, and then to Switching Power Supply
Electrochemical capacitor and oscillator occur failure alarmed.
2. a kind of Switching Power Supply ripple voltage detection method based on detection techniques according to claim 1, its feature exists
In：The specific method of the step 1 is：By transistor amplifier to ripple alternating voltage in the output voltage of Switching Power Supply
Amplification, is then filtered the flip-flop in switch power source output voltage by RC filter circuits.
3. a kind of Switching Power Supply ripple voltage detection method based on detection techniques according to claim 1 or 2, its feature
It is：The specific steps of the step 2 include：
(1) 3 Q value identical detecting circuits are designed, its tuned frequency is respectively W0, W1 and W2, wherein, W0-W1=W2-W0；
In above formula, W0 is frequency when Switching Power Supply is normally run, and W1 is Switching Power Supply failure warning frequency, and W2 is to examine circuit
Frequency；
(2) according to the capacitance characteristic of Switching Power Supply, the warning width of ripple alternating voltage in the output voltage of Switching Power Supply is calculated
Value IR++；
(3) voltage magnitude for measuring three detecting circuits is respectively IR0, IR1 and IR2, and calculates switch according to equation below
The concussion frequency Wk of ripple alternating voltage in the output voltage of power supply；
(1+jQ (W0/Wk-Wk/W0))/(1+jQ (W1/Wk-Wk/W1))=IR1/IR0
In above formula, j is that imaginary number j square is Q values that -1, Q is High " Q " Circuit；
(4) according to the concussion frequency Wk of ripple alternating voltage in the output voltage of Switching Power Supply, calculated out using equation below
The voltage magnitude IRk of ripple alternating voltage in the output voltage in powered-down source；
IRk=(1+jQ (W0/Wk-Wk/W0)) IR0
(5) the concussion frequency Wk and Switching Power Supply failure warning frequency of ripple alternating voltage in the output voltage of Switching Power Supply are compared
W1 size, if Wk<W1, then judge that Switching Power Supply oscillator goes wrong；
(6) the voltage magnitude IRk of ripple alternating voltage in the output voltage of Switching Power Supply and the output voltage of Switching Power Supply are compared
The warning amplitude IR++ of middle ripple alternating voltage size, if IRk>IR++, then judge that Switching Power Supply electrolysis electric capacity is asked
Topic.
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Cited By (8)
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| CN107817453A (en) * | 2017-09-19 | 2018-03-20 | 广东科鉴检测工程技术有限公司 | A kind of method and apparatus for monitoring power system stability |
| CN108549039A (en) * | 2018-04-13 | 2018-09-18 | 同济大学 | A kind of Switching Power Supply ripple measuring circuit |
| CN110687471A (en) * | 2019-08-29 | 2020-01-14 | 国网浙江省电力有限公司金华供电公司 | Direct current power supply aging monitoring system |
| CN112666375A (en) * | 2020-12-18 | 2021-04-16 | 陕西航空电气有限责任公司 | Method for detecting output ripple voltage of aviation TRU |
| CN113075445A (en) * | 2020-01-06 | 2021-07-06 | 广州汽车集团股份有限公司 | Ripple protection method and circuit for high-voltage device, electronic controller and storage medium |
| CN113945857A (en) * | 2021-10-25 | 2022-01-18 | 上海电气风电集团股份有限公司 | Detection device and method for switching power supply |
| CN116520182A (en) * | 2023-05-11 | 2023-08-01 | 珠海中瑞电力科技有限公司 | DCS device power supply module abnormality early diagnosis method |
| CN117970167A (en) * | 2024-03-28 | 2024-05-03 | 深圳市力生美半导体股份有限公司 | Switching power supply fault prediction device and method and electronic equipment |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
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| CN108549039A (en) * | 2018-04-13 | 2018-09-18 | 同济大学 | A kind of Switching Power Supply ripple measuring circuit |
| CN110687471A (en) * | 2019-08-29 | 2020-01-14 | 国网浙江省电力有限公司金华供电公司 | Direct current power supply aging monitoring system |
| CN113075445A (en) * | 2020-01-06 | 2021-07-06 | 广州汽车集团股份有限公司 | Ripple protection method and circuit for high-voltage device, electronic controller and storage medium |
| CN113075445B (en) * | 2020-01-06 | 2022-08-19 | 广州汽车集团股份有限公司 | Ripple protection method and circuit for high-voltage device, electronic controller and storage medium |
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| CN113945857A (en) * | 2021-10-25 | 2022-01-18 | 上海电气风电集团股份有限公司 | Detection device and method for switching power supply |
| CN116520182A (en) * | 2023-05-11 | 2023-08-01 | 珠海中瑞电力科技有限公司 | DCS device power supply module abnormality early diagnosis method |
| CN116520182B (en) * | 2023-05-11 | 2023-11-14 | 珠海中瑞电力科技有限公司 | DCS device power supply module abnormality early diagnosis method |
| CN117970167A (en) * | 2024-03-28 | 2024-05-03 | 深圳市力生美半导体股份有限公司 | Switching power supply fault prediction device and method and electronic equipment |
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