CN117792059A - Overvoltage protection method, control device and switching power supply - Google Patents
Overvoltage protection method, control device and switching power supply Download PDFInfo
- Publication number
- CN117792059A CN117792059A CN202410200210.9A CN202410200210A CN117792059A CN 117792059 A CN117792059 A CN 117792059A CN 202410200210 A CN202410200210 A CN 202410200210A CN 117792059 A CN117792059 A CN 117792059A
- Authority
- CN
- China
- Prior art keywords
- voltage amplitude
- voltage
- real
- digital potentiometer
- power supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 73
- 230000001105 regulatory effect Effects 0.000 claims abstract description 17
- 230000006870 function Effects 0.000 claims description 18
- 230000004044 response Effects 0.000 claims description 17
- 238000012546 transfer Methods 0.000 claims description 17
- 230000008569 process Effects 0.000 claims description 14
- 230000001052 transient effect Effects 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 4
- 238000012544 monitoring process Methods 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 3
- 230000000630 rising effect Effects 0.000 description 3
- 239000003990 capacitor Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 230000010485 coping Effects 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The application relates to an overvoltage protection method, a control device and a switching power supply, wherein the overvoltage protection method comprises the following steps: acquiring a first voltage amplitude of a power input end; acquiring the real-time temperature of the switching circuit based on a preset temperature curve and a first voltage amplitude; and regulating the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit. According to the invention, through judging overvoltage and then carrying out secondary judgment through temperature rise, and when the switch circuit is overvoltage, the resistance value output by the digital potentiometer can be preferentially regulated, so that the switch power supply can normally operate under the condition of no power failure, the damage of elements in the switch power supply caused by the over-high voltage input by a power supply grid can be effectively avoided, and the use of no power failure can be realized after the voltage exceeds a threshold value, thereby the power supply of a precision instrument or medical equipment can be more stably and reliably carried out.
Description
Technical Field
The application relates to the technical field of power supplies, in particular to an overvoltage protection method, a control device and a switching power supply.
Background
With the development and innovation of power electronics technology, the technology of switching power supplies is also continuously innovating. Compared with a linear power supply, the switching power supply has the advantages of easy control, high efficiency, small volume, good reliability and easy realization of protection, is widely applied to equipment such as television power supplies, mobile phone chargers, LEDs, industrial instruments, power adapters and the like, and is an indispensable power supply mode for rapid development of the electronic information industry at present.
The switching power supply is generally used for converting an ac voltage input by a power supply grid into a preset dc voltage for load operation. In general, in order to avoid damage to elements in a switching power supply caused by an excessively high ac voltage input from a power supply grid, the switching power supply is provided with an overvoltage protection circuit, and when the ac voltage exceeds a preset threshold value, a controller turns off all switching elements in the switching power supply to stop power supply to a load. When the alternating voltage of the power supply grid exceeds a preset threshold value, all switching elements in the switching power supply are directly turned off to stop supplying power to the load, so that the load cannot be normally powered for use, and for some precise instruments or medical equipment, larger loss can be caused by power failure.
Disclosure of Invention
The invention mainly aims to provide an overvoltage protection method, which aims to solve the technical problem that when the input voltage of a switching power supply exceeds a threshold value, a controller can directly disconnect all switching elements in the switching power supply to stop supplying power to a load, so that larger loss is easily caused.
In order to achieve the above object, the present invention provides an overvoltage protection method applied to a switching power supply, the switching power supply includes a power input terminal, a switching circuit and a power output terminal which are electrically connected in sequence, a digital potentiometer is disposed between the power input terminal and the input terminal of the switching circuit, the overvoltage protection method includes the following steps:
acquiring a first voltage amplitude of a power input end;
acquiring the real-time temperature of the switching circuit based on a preset temperature curve and a first voltage amplitude;
and regulating the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit.
In one embodiment, the step of obtaining the first voltage amplitude of the power input terminal includes:
acquiring a plurality of second voltage amplitudes of the power input end in a preset time period;
filtering transient spikes in the second voltage amplitude based on the first algorithm and the plurality of second voltage amplitudes;
and determining the filtered second voltage amplitude as the first voltage amplitude.
In an embodiment, the step of obtaining the real-time temperature of the switching circuit based on the preset temperature curve and the first voltage amplitude includes:
acquiring a temperature rise amplitude of the switching circuit, which changes along with time, according to the first voltage amplitude;
generating a preset temperature curve according to the first voltage amplitude and the temperature rise amplitude;
acquiring real-time temperature and corresponding operation time points of the switching circuit in the operation process based on a preset temperature curve and a first voltage amplitude;
and comparing the temperature value of the corresponding position of the real-time temperature and the preset temperature curve according to the operation time point, and determining that the real-time temperature exceeds a threshold value.
In an embodiment, the step of adjusting the resistance value output by the digital potentiometer according to the voltage amplitude of the input end and the real-time temperature of the switching circuit includes:
when the real-time temperature exceeds the threshold value, acquiring a resistance range and an adjustment coefficient output by the digital potentiometer;
establishing a transfer function of the response of the digital potentiometer according to the first voltage amplitude, the resistance range and the adjustment coefficient;
and regulating the resistance value output by the digital potentiometer according to the real-time temperature, the first voltage amplitude and the transfer function.
In one embodiment, the step of establishing a transfer function of the digital potentiometer response according to the first voltage amplitude, the resistance range and the adjustment coefficient includes:
let the resistance of the digital potentiometer be R, the first voltage amplitude be V, the current amplitude be I, the resistance after instantaneous adjustment be R', then there are:
R'=R+k*(V-V_th)；
wherein k is an adjustment coefficient, and V_th is an overvoltage threshold;
the transfer function of the digital potentiometer response is as follows:
G(s)=I(s)/V(s)=(R'+R)/(R'*s+1)；
where s is the Laplace transform domain variable.
In an embodiment, the step of obtaining the real-time temperature of the switching circuit based on the preset temperature curve and the first voltage amplitude includes:
acquiring a preset temperature of a preset temperature curve at a first voltage amplitude, and determining a difference value between the real-time temperature and the preset temperature;
the step of adjusting the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit comprises the following steps:
and regulating the resistance value output by the digital potentiometer in real time according to the difference value of the first voltage amplitude, the real-time temperature and the preset temperature.
In an embodiment, the overvoltage protection method further comprises:
acquiring a third voltage amplitude value of a power input end and a resistance value range of a digital potentiometer;
determining the maximum partial pressure value of the digital potentiometer according to the resistance range of the digital potentiometer;
judging whether the third voltage amplitude exceeds the maximum voltage division value of the digital potentiometer according to the third voltage amplitude and the maximum voltage division value;
when the third voltage amplitude exceeds the maximum voltage division value, the switch circuit is controlled to be turned off.
In an embodiment, the overvoltage protection method further comprises:
acquiring a fourth voltage amplitude of the power supply output end;
according to the fourth voltage amplitude and the preset voltage amplitude, regulating a pulse width signal input to the switching circuit;
and when the pulse width signal is lower than a preset value, regulating the resistance value of the digital potentiometer.
In addition, to achieve the above object, the present invention also provides a control device including:
a memory;
and a processor storing an overvoltage protection program stored on the memory and executed by the processor, the overvoltage protection program implementing the overvoltage protection method as described above when executed by the processor.
In addition, in order to achieve the above object, the present invention also provides a switching power supply, which is characterized by comprising the control device as described above.
According to the embodiment of the invention, the first voltage amplitude of the power input end is obtained, the real-time temperature of the switching power supply is obtained by combining with the preset temperature curve, the resistance value output by the digital potentiometer is regulated according to the real-time temperature and the first voltage amplitude, the overvoltage is judged, the secondary judgment is made through temperature rise, and the resistance value output by the digital potentiometer can be preferentially regulated when the switching power supply is overvoltage, so that the switching power supply can normally operate under the condition of no power failure, the damage of elements in the switching power supply caused by the overhigh voltage input by a power supply grid can be effectively avoided, the no power failure can be realized when the voltage exceeds the threshold value, and the power supply of a precise instrument or medical equipment can be more stably and reliably supplied.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic flow chart of an overvoltage protection method according to an embodiment of the invention;
FIG. 2 is a schematic flow chart of an overvoltage protection method according to another embodiment of the invention;
FIG. 3 is a schematic flow chart of an overvoltage protection method according to another embodiment of the invention;
FIG. 4 is a schematic flow chart of an overvoltage protection method according to another embodiment of the invention;
FIG. 5 is a schematic flow chart of an overvoltage protection method according to another embodiment of the invention;
FIG. 6 is a schematic flow chart of an overvoltage protection method according to another embodiment of the invention;
fig. 7 is a schematic flow chart of an overvoltage protection method according to another embodiment of the invention.
The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention, and that well-known modules, units and their connections, links, communications or operations with each other are not shown or described in detail. Also, the described features, architectures, or functions may be combined in any manner in one or more implementations. It will be appreciated by those skilled in the art that the various embodiments described below are for illustration only and are not intended to limit the scope of the invention. It will be further appreciated that the modules or units or processes of the embodiments described herein and illustrated in the drawings may be combined and designed in a wide variety of different configurations. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The definitions of the various terms or methods set forth in the following embodiments are generally based on the broad concepts that may be practiced with the disclosure in the examples except where logically no such definitions are set forth, and in the following understanding, each specific lower specific definition of a term or method is to be considered an inventive subject matter and should not be interpreted as a narrow sense or as a matter of prejudice to the contrary that the specification does not disclose such a specific definition. Similarly, the order of the steps in the method is flexible and variable on the premise that the steps can be logically implemented, and specific lower limits in various nouns or generalized concepts of the method are within the scope of the invention.
With the development and innovation of power electronics technology, the technology of switching power supplies is also continuously innovating. Compared with a linear power supply, the switching power supply has the advantages of easy control, high efficiency, small volume, good reliability and easy realization of protection, is widely applied to equipment such as television power supplies, mobile phone chargers, LEDs, industrial instruments, power adapters and the like, and is an indispensable power supply mode for rapid development of the electronic information industry at present.
The switching power supply is generally used for converting an ac voltage input by a power supply grid into a preset dc voltage for load operation. In general, in order to avoid damage to elements in a switching power supply caused by an excessively high ac voltage input from a power supply grid, the switching power supply is provided with an overvoltage protection circuit, and when the ac voltage exceeds a preset threshold value, a controller turns off all switching elements in the switching power supply to stop power supply to a load.
In the process of designing and implementing the present application, the inventors found that at least the following problems exist: when the alternating current voltage of the power supply grid exceeds a preset threshold value, all switching elements in the switching power supply are directly turned off, and the power supply to the load is stopped, so that the load cannot be normally powered for use, and for some precise instruments or medical equipment, larger loss can be caused by power failure.
For this purpose, the invention proposes an overvoltage protection method; it will be appreciated that the control device for over-voltage protection is provided with a control device for storing and executing the method described below, and the control device may be implemented by a main controller, for example, an MCU (Micro controller Unit, micro control unit), DSP (Digital Signal Process, digital signal processing Chip), FPGA (Field Programmable Gate Array, programmable gate array Chip), SOC (System On Chip), etc.
Referring to fig. 1, fig. 1 is a schematic flow chart of an overvoltage protection method according to an embodiment of the present invention, where the overvoltage protection method according to the embodiment is applied to a switching power supply, and the switching power supply includes a power input end, a switching circuit, and a power output end that are electrically connected in sequence, and is characterized in that a digital potentiometer is disposed between the power input end and the input end of the switching circuit, and the overvoltage protection method includes steps S100-S300, where:
s100, acquiring a first voltage amplitude of a power input end;
s200, acquiring real-time temperature of a switching circuit based on a preset temperature curve and a first voltage amplitude;
s300, according to the first voltage amplitude and the real-time temperature of the switching circuit, the resistance value output by the digital potentiometer is adjusted.
In this embodiment, under the indoor operation condition of the switch circuit, when the first voltage amplitude is abnormally increased, an abnormal temperature rising phenomenon occurs, so that in order to make the judgment at normal temperature more accurate and reliable, when the first voltage amplitude is judged to exceed the preset value, the real-time temperature of the switch circuit is obtained to judge the temperature value corresponding to the real-time temperature and the preset temperature curve, when the real-time temperature exceeds the threshold value, the resistance value output by the digital potentiometer is regulated, and the temperature rising is used for secondary judgment. Meanwhile, the temperature of the switching circuit is obtained in real time, so that the abnormal voltage rising condition can be accurately judged in a room temperature environment, and the safety and reliability of the circuit are further improved.
On the basis, the operation parameters of the switching circuit can be optimized to adapt to the operation requirements under different environments. For example, the resistance value output by the digital potentiometer can be adjusted according to the comparison result of the real-time temperature and the preset temperature curve, so that the circuit can stably run in various environments. In addition, the running state of the circuit can be monitored in real time according to the real-time temperature of the circuit and a preset temperature curve, so that measures can be taken in time to adjust when abnormal conditions occur.
It can be understood that the digital potentiometer is a programmable analog device (PDA), and in this embodiment, in order to further improve the performance and flexibility of the switching circuit, the digital potentiometer is specifically a programmable resistor, and the resistance value of the resistor can be adjusted by changing the voltage on the resistor disc. In order to better adjust the parameters of the switching circuit, the switching circuit of the embodiment may be further connected in series or parallel with other programmable analog devices, such as a programmable capacitor, a programmable inductor, etc., so as to achieve finer parameter adjustment. Specifically, the programmable resistor realizes the adjustment of the circuit performance by changing the resistance value; the programmable capacitor and the programmable inductor achieve similar purposes by changing the capacitance value and the inductance value respectively. The programmable analog devices can be programmed according to external control signals, so that the circuit parameters can be adjusted in real time, the flexibility of the circuit is improved, and the circuit can keep good performance in a wider range by adjusting the parameters of the analog devices, so that the reliability of the circuit is improved.
In this embodiment, in order to better implement adjustment of the resistance value output by the digital potentiometer, the trend of the voltage fluctuation can be predicted by analyzing and modeling the historical data, so that corresponding control measures are adopted in advance, the influence of the voltage fluctuation on the digital potentiometer is reduced, the voltage fluctuation condition monitored in real time is dynamically adjusted, control parameters such as PID parameters and the like are dynamically adjusted to achieve better control effects, and a control algorithm is automatically adjusted according to the voltage fluctuation condition monitored in real time so as to adapt to different working conditions, thereby ensuring stable operation of the digital potentiometer under various working conditions and improving the control precision and reliability of the digital potentiometer.
Further, referring to fig. 2, another embodiment of the present invention provides an overvoltage protection method, based on the embodiment shown in fig. 1, the step of obtaining the first voltage amplitude of the power input terminal includes S110-S130, where:
s110, acquiring a plurality of second voltage amplitudes of the power input end in a preset time period;
s120, filtering transient spike signals in the second voltage amplitude based on the first algorithm and a plurality of the second voltage amplitudes;
s130, determining the filtered second voltage amplitude as the first voltage amplitude.
In this embodiment, in order to further avoid the influence of the transient spike on the control of the digital potentiometer, the first algorithm is used to smooth the second voltage amplitude, so that the transient spike signal can be effectively filtered, and the control accuracy and stability of the digital potentiometer are improved. Meanwhile, the control strategy can be further optimized by monitoring the voltage fluctuation condition in real time, so that the stable operation of the digital potentiometer under various working conditions is ensured. Specifically, the embodiment obtains a plurality of second voltage amplitudes within a preset period, for example, a plurality of second voltage amplitudes within 1 second, and smoothes the second voltage amplitudes to obtain the first voltage amplitude. In the process of implementing the first algorithm to smooth the second voltage amplitude, a moving average method, an exponential smoothing method, a kalman filtering method or the like can be adopted. Taking the moving average method as an example, we first acquire a plurality of second voltage amplitudes within a preset period, for example, a plurality of second voltage amplitudes within 1 second. These second voltage magnitudes are then averaged to obtain a first voltage magnitude. By the method, instantaneous spike signals can be effectively filtered, and the control precision and stability of the digital potentiometer are improved.
Further, referring to fig. 3, a further embodiment of the present invention provides an overvoltage protection method, based on the embodiment shown in fig. 1, the step of obtaining the real-time temperature of the switching circuit based on the preset temperature curve and the first voltage amplitude includes S210-S240, where:
s210, acquiring a temperature rise amplitude of the switching circuit, which changes along with time, according to the first voltage amplitude;
s220, generating a preset temperature curve according to the first voltage amplitude and the temperature rise amplitude;
s230, acquiring real-time temperature and corresponding operation time points of the switching circuit in the operation process based on a preset temperature curve and a first voltage amplitude;
s240, comparing the real-time temperature with the temperature value of the corresponding position of the preset temperature curve according to the operation time point, and determining that the real-time temperature exceeds a threshold value.
In this embodiment, in order to avoid an unnecessary false triggering condition and eliminate external interference factors, when the first voltage amplitude does not exceed the threshold, the temperature of the switching circuit exceeds the threshold, the digital potentiometer is not adjusted and controlled, if the voltage does not exceed the threshold, but the temperature exceeds, specifically, another sensor acquires a signal, and the switching power supply is turned off as a whole.
In this embodiment, the switch circuit has a corresponding safe operation temperature value at a corresponding operation time point, for example, in an initial start-up period, after each electronic element of the switch circuit is operated at about 20 ℃ for one hour, the temperature can be at 40 ℃, when the temperature fluctuates up and down at the value, the safe operation temperature value is determined, the real-time temperature can be better compared with the real-time temperature by setting the temperature value on a preset temperature curve, the deviation degree of the real-time temperature and the preset temperature curve is determined, and the parameters of the digital potentiometer are adjusted to control the operation state of the switch circuit, so that the switch circuit returns to the normal operation range as soon as possible. If the real-time temperature still exceeds the threshold value and reaches or approaches the limit temperature of the switching circuit after the digital potentiometer is adjusted to the maximum resistance value, automatic protection measures are implemented to prevent equipment damage, including reducing the operating voltage, reducing the load or closing the switching circuit, etc. And automatically recovering the normal operation of the switching circuit until the real-time temperature is recovered to the normal range. And according to the operation experience and the real-time data, the preset temperature curve is updated regularly so as to improve the operation efficiency and the safety of the switching circuit. Through the comparison of the real-time temperature monitoring and the preset temperature curve of the switch circuit, the intelligent management of the switch circuit is realized, and the service life and the reliability of the equipment are improved. Through real-time supervision voltage and temperature variation, realize the intelligent regulation and control to switch circuit, effectively prevent overheated phenomenon, ensure equipment safety, steady operation. Meanwhile, an early warning mechanism and automatic protection measures are adopted, so that the fault coping capacity of the equipment is improved, and the fault loss is reduced. In addition, through the periodic update preset temperature curve, the intelligent management of the switch circuit is realized, and the service life and the reliability of the equipment are improved. In practical application, the embodiment can be properly adjusted according to the needs to meet the requirements of different scenes.
Further, referring to fig. 4, a further embodiment of the present invention provides an overvoltage protection method, based on the embodiment shown in fig. 3, the step of adjusting the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit includes S310-S330, where:
s310, when the real-time temperature exceeds a threshold value, acquiring a resistance range and an adjustment coefficient output by the digital potentiometer;
s320, establishing a transfer function of the response of the digital potentiometer according to the first voltage amplitude, the resistance range and the adjustment coefficient;
s330, adjusting the resistance value output by the digital potentiometer according to the real-time temperature, the first voltage amplitude and the transfer function.
In this embodiment, the range of the resistance value and the adjustment coefficient of the output of the digital potentiometer are determined first, so that the control device can determine the direction and the amplitude of the resistance value adjustment of the digital potentiometer according to the condition that the real-time temperature exceeds the threshold value. This step can be achieved by comparing the real-time temperature with a threshold, if the real-time temperature is higher than the threshold, the resistance needs to be reduced; otherwise, if the real-time temperature is lower than the threshold value, the resistance value needs to be increased. Then, according to the first voltage amplitude, the speed of digital potentiometer resistance adjustment is determined. There is a correlation between voltage amplitude and resistance, a higher voltage amplitude generally means a faster rate of resistance adjustment. By establishing the correlation, the potentiometer can be ensured to meet the switching requirement of the switching circuit more accurately when the resistance value is adjusted. And then, according to the established transfer function, the output resistance value of the digital potentiometer is regulated in real time. The transfer function models the relation among the real-time temperature, the first voltage amplitude and the resistance value, the accurate control of the resistance value can be realized by adjusting parameters, and the response of the digital potentiometer is required to be monitored in real time in the process of adjusting the resistance value so as to ensure that the response can be adjusted within a preset range. If the output resistance value is found to be beyond the preset range, corresponding measures can be taken for correction so as to ensure the stable operation of the switch circuit, so that the switch circuit has stronger adaptability and reliability and better performance is realized.
In this embodiment, the step of establishing a transfer function of the digital potentiometer response according to the first voltage amplitude, the resistance range and the adjustment coefficient includes:
as mentioned above, the resistance of the digital potentiometer will vary with the voltage,
let the resistance of the digital potentiometer be R, the first voltage amplitude be V, the current amplitude be I, the resistance after instantaneous adjustment be R', then there are:
R'=R+k*(V-V_th)；
in the formula, k is an adjustment coefficient, v_th is an overvoltage threshold, v_th is the highest voltage value that the digital potentiometer can withstand, and when the input voltage V exceeds the overvoltage threshold v_th, the resistance R' is adjusted according to the adjustment coefficient k.
The transfer function of the digital potentiometer response is as follows:
G(s)=I(s)/V(s)=(R'+R)/(R'*s+1)；
where s is the Laplace transform domain variable and the transfer function is used to describe the relationship between the input voltage V and the output current I.
In this embodiment, the transfer function of the digital potentiometer response represents the voltage regulation capability of the digital potentiometer in the event of an overvoltage condition. In particular, when the voltage exceeds the overvoltage threshold v_th, the digital potentiometer enters a continuously adjusted mode, the response of which can be described by this first-order hysteresis model. Through the model, the voltage adjustment capability of the digital potentiometer under the overvoltage condition can be known, so that references are provided for circuit design and fault diagnosis. In practical application, we can adjust the overvoltage threshold v_th and the adjustment coefficient k according to the actual requirement, so as to meet the requirements in different scenes. The response transfer function of the digital potentiometer is established by adopting the first voltage amplitude, the resistance range and the adjustment coefficient, so that the response characteristic of the digital potentiometer under the overvoltage condition is analyzed, the overvoltage protection of a switch circuit is met, and meanwhile, the use safety of the digital potentiometer can be well protected, and the service life of a device is prolonged.
Further, referring to fig. 5, a further embodiment of the present invention provides an overvoltage protection method, based on the embodiment shown in fig. 1, the step of obtaining the real-time temperature of the switching circuit based on the preset temperature curve and the first voltage amplitude includes S250, where:
s250, acquiring a preset temperature of a preset temperature curve at a first voltage amplitude, and determining a difference value between the real-time temperature and the preset temperature;
the step of adjusting the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit includes S340, wherein:
s340, according to the first voltage amplitude, the difference value of the real-time temperature and the preset temperature, the resistance value output by the digital potentiometer is adjusted in real time.
In this embodiment, the preset temperature curve may include preset temperatures corresponding to the first voltage amplitudes, for example, when 12V is used, the preset temperature is 20-40 ℃, and when 24V is used, the preset temperature is 20-50 ℃, so as to accurately determine whether the real-time temperature exceeds the threshold. To ensure accuracy in adjusting the resistance, we need to know the real-time temperature. A temperature sensor may be used to measure the ambient temperature and convert the temperature signal to a digital signal. According to the first voltage amplitude, the safe operation temperature can be determined by operating the temperature data corresponding to the first voltage amplitude on a preset temperature curve, and then the difference between the safe operation temperature and the preset voltage amplitude and the preset temperature can be calculated by combining the real-time temperature. These two differences will be used as the basis for real-time adjustment of the resistance. According to the calculated difference, we need to adjust the output resistance of the digital potentiometer in real time. This may be achieved by a microcontroller or other processor. The specific method is to adjust the resistance according to the magnitude of the difference value and a preset algorithm. For example, when the voltage difference or the temperature difference is large, the resistance of the potentiometer may be increased. In the process of adjusting the resistance in real time, feedback and calibration are needed to the system to ensure the accuracy of the adjusting effect. This can be achieved by monitoring system performance indicators such as control accuracy, response speed, etc. If the system performance is found to be poor, parameters can be timely adjusted, and the stability and reliability of the system are improved. The digital potentiometer has the advantages of high response speed, high control precision and strong adaptability, and can keep good performance under different working environments, voltage and temperature changes are required to be monitored in real time, and the resistance value is adjusted according to actual conditions.
Further, referring to fig. 6, another embodiment of the present invention provides an overvoltage protection method, based on the embodiment shown in fig. 1, the overvoltage protection method further includes S400-S600, where:
s400, acquiring a resistance range of the digital potentiometer, and determining a maximum partial pressure value of the digital potentiometer;
s500, judging whether the third voltage amplitude exceeds the maximum voltage division value of the digital potentiometer according to the first voltage amplitude and the maximum voltage division value;
and S600, when the first voltage amplitude exceeds the maximum voltage division value, the switch circuit is controlled to be turned off.
In this embodiment, the maximum voltage division value of the digital potentiometer, that is, the maximum sustainable voltage value of the digital potentiometer, is also the safety threshold value of the digital potentiometer for dividing the voltage in the switch circuit. In practical applications, in order to ensure the stability and safety of the digital potentiometer, the digital potentiometer needs to be reasonably set and monitored.
In this embodiment, the user uploads the resistance range of the digital potentiometer to the control device through the intelligent terminal, which is the basis for determining the maximum partial pressure value of the digital potentiometer. Specifically, the range of resistance values may be obtained by a parameter manual or actual measurement provided by the manufacturer. The size of the resistance range directly influences the performance of the digital potentiometer in practical application. And judging whether the third voltage amplitude exceeds the maximum voltage division value of the digital potentiometer according to the first voltage amplitude and the maximum voltage division value. This step is to ensure that the digital potentiometer will not exceed its bearing range during the voltage division process, thereby ensuring its stability and safety. When the first voltage amplitude exceeds the maximum voltage division value, the switch circuit needs to be controlled to be turned off. This is a key step of this embodiment, and by monitoring the voltage amplitude in real time, the situation that may cause a safety hazard can be found and processed at the first time. The stability and the safety of the anti-collision device in practical application can be effectively ensured. Through real-time monitoring of the resistance range and the voltage amplitude of the digital potentiometer and automatic control of the switch circuit, the omnibearing protection of the voltage dividing circuit of the digital potentiometer is realized. In practical application, the embodiment can be adjusted and optimized according to the needs to meet the requirements of different scenes.
Further, referring to fig. 7, a further embodiment of the present invention provides an overvoltage protection method, based on the embodiment shown in fig. 1, the overvoltage protection method further includes S700-S900, where:
s700, acquiring a third voltage amplitude of the power supply output end;
s800, according to the third voltage amplitude and the preset voltage amplitude, regulating a pulse width signal input to the switching circuit;
s900, when the pulse width signal is lower than a preset value, the resistance value of the digital potentiometer is adjusted.
In this embodiment, in order to prevent the output voltage from being out of control due to the overlarge input voltage, the output voltage is monitored in real time, and when the output third voltage amplitude exceeds the preset voltage amplitude, the pulse width signal is adjusted in time so as to keep the output voltage within a reasonable range. Thus, not only the stability of the output voltage can be ensured, but also the damage to the equipment caused by the overhigh voltage can be avoided. In addition, when the pulse width signal input by the switching circuit is lower than a preset value, for example, the duty ratio is lower than 20%, the control device can automatically adjust the resistance value of the word potentiometer. By increasing the resistance value, the voltage input to the switching power supply is reduced, and the duty ratio is increased, so that the voltage output of the switching circuit can be ensured to be stable and reliable even under the condition that the pulse width signal is low. The output voltage is prevented from being out of control due to overlarge input voltage, and meanwhile, the voltage output of the switch circuit is ensured to be stable and reliable.
The invention also proposes a control device comprising:
a memory;
and a processor, storing an overvoltage protection program in the memory and executed by the processor, wherein the overvoltage protection control program, when executed by the processor, implements the overvoltage protection method according to the above embodiment.
It should be noted that, because the control device of the present invention is based on the above-mentioned overvoltage protection method, the embodiments of the control device of the present invention include all the technical solutions of all the embodiments of the above-mentioned overvoltage protection method, and the achieved technical effects are identical, and are not described herein again.
The invention also provides a switching power supply which comprises the control device according to the embodiment.
It should be noted that, because the switching power supply of the present invention is based on the control device, embodiments of the switching power supply of the present invention include all technical solutions of all embodiments of the control device, and the achieved technical effects are identical, and are not described herein again.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.
From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) as described above, comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to perform the method according to the embodiments of the present invention.
The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the invention, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.
Claims (10)
1. The overvoltage protection method is applied to a switching power supply, and the switching power supply comprises a power supply input end, a switching circuit and a power supply output end which are electrically connected in sequence, and is characterized in that a digital potentiometer is arranged between the power supply input end and the input end of the switching circuit, and the overvoltage protection method comprises the following steps:
acquiring a first voltage amplitude of a power input end;
acquiring the real-time temperature of the switching circuit based on a preset temperature curve and a first voltage amplitude;
and regulating the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit.
2. The method of claim 1, wherein the step of obtaining a first voltage magnitude at the power input comprises:
acquiring a plurality of second voltage amplitudes of the power input end in a preset time period;
filtering transient spikes in the second voltage amplitude based on the first algorithm and the plurality of second voltage amplitudes;
and determining the filtered second voltage amplitude as the first voltage amplitude.
3. The method of claim 1, wherein the step of obtaining the real-time temperature of the switching circuit based on the preset temperature profile and the first voltage magnitude comprises:
acquiring a temperature rise amplitude of the switching circuit, which changes along with time, according to the first voltage amplitude;
generating a preset temperature curve according to the first voltage amplitude and the temperature rise amplitude;
acquiring real-time temperature and corresponding operation time points of the switching circuit in the operation process based on a preset temperature curve and a first voltage amplitude;
and comparing the temperature value of the corresponding position of the real-time temperature and the preset temperature curve according to the operation time point, and determining that the real-time temperature exceeds a threshold value.
4. The method of claim 3, wherein the step of adjusting the resistance of the digital potentiometer output based on the first voltage magnitude and the real-time temperature of the switching circuit comprises:
when the real-time temperature exceeds the threshold value, acquiring a resistance range and an adjustment coefficient output by the digital potentiometer;
establishing a transfer function of the response of the digital potentiometer according to the first voltage amplitude, the resistance range and the adjustment coefficient;
and regulating the resistance value output by the digital potentiometer according to the real-time temperature, the first voltage amplitude and the transfer function.
5. The method of overvoltage protection according to claim 4, wherein the step of establishing a transfer function of the digital potentiometer response based on the first voltage magnitude, the range of resistances, and the adjustment factor comprises:
let the resistance of the digital potentiometer be R, the first voltage amplitude be V, the current amplitude be I, the resistance after instantaneous adjustment be R', then there are:
R'=R+k*(V-V_th)；
wherein k is an adjustment coefficient, and V_th is an overvoltage threshold;
the transfer function of the digital potentiometer response is as follows:
G(s)=I(s)/V(s)=(R'+R)/(R'*s+1)；
where s is the Laplace transform domain variable.
6. The method of claim 1, wherein the step of obtaining the real-time temperature of the switching circuit based on the preset temperature profile and the first voltage magnitude comprises:
acquiring a preset temperature of a preset temperature curve at a first voltage amplitude, and determining a difference value between the real-time temperature and the preset temperature;
the step of adjusting the resistance value output by the digital potentiometer according to the first voltage amplitude and the real-time temperature of the switching circuit comprises the following steps:
and regulating the resistance value output by the digital potentiometer in real time according to the difference value of the first voltage amplitude, the real-time temperature and the preset temperature.
7. The overvoltage protection method according to claim 6, further comprising:
acquiring the resistance range of the digital potentiometer, and determining the maximum partial pressure value of the digital potentiometer;
judging whether the third voltage amplitude exceeds the maximum voltage division value of the digital potentiometer according to the first voltage amplitude and the maximum voltage division value;
when the first voltage amplitude exceeds the maximum voltage division value, the control switch circuit is turned off.
8. The overvoltage protection method according to claim 1, further comprising:
acquiring a third voltage amplitude of the power supply output end;
according to the third voltage amplitude and the preset voltage amplitude, regulating a pulse width signal input to the switching circuit;
and when the pulse width signal is lower than a preset value, regulating the resistance value of the digital potentiometer.
9. A control device, characterized in that the control device comprises:
a memory;
a processor, an overvoltage protection program stored on the memory and executed by the processor, which overvoltage protection program, when executed by the processor, implements the overvoltage protection method according to any one of claims 1-8.
10. A switching power supply comprising a control device as claimed in claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410200210.9A CN117792059B (en) | 2024-02-23 | 2024-02-23 | Overvoltage protection method, control device and switching power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410200210.9A CN117792059B (en) | 2024-02-23 | 2024-02-23 | Overvoltage protection method, control device and switching power supply |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117792059A true CN117792059A (en) | 2024-03-29 |
| CN117792059B CN117792059B (en) | 2024-05-31 |
Family
ID=90392834
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410200210.9A Active CN117792059B (en) | 2024-02-23 | 2024-02-23 | Overvoltage protection method, control device and switching power supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117792059B (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4636910A (en) * | 1985-04-11 | 1987-01-13 | Canadian General Electric Company Limited | Varistor overvoltage protection system with temperature systems |
| CN104134981A (en) * | 2014-07-02 | 2014-11-05 | 邯郸美的制冷设备有限公司 | Overvoltage protection device for air conditioner, overvoltage protection method and air conditioner |
| CN105514942A (en) * | 2014-09-05 | 2016-04-20 | 纬创资通股份有限公司 | protection method and protection device for electronic device |
| CN105932645A (en) * | 2016-05-31 | 2016-09-07 | 联想(北京)有限公司 | Switching power supply and electronic equipment |
| CN206727876U (en) * | 2017-05-27 | 2017-12-08 | 南宁职业技术学院 | Digital step-down switching power supply device |
| CN108572689A (en) * | 2017-03-10 | 2018-09-25 | 台达电子企业管理（上海）有限公司 | Switching Power Supply, excess temperature control guard method and Poewr control method |
| CN213342041U (en) * | 2020-11-17 | 2021-06-01 | 东莞市川信电子科技有限公司 | Programmable temperature setting power supply circuit |
| CN114034913A (en) * | 2021-11-18 | 2022-02-11 | 广东电网有限责任公司 | Method, device and system for measuring overvoltage of lightning intrusion wave of transformer substation |
| CN116885828A (en) * | 2023-09-08 | 2023-10-13 | 深圳市力生美半导体股份有限公司 | Switching power supply detection circuit, power supply method, charging device, and storage medium |
-
2024
- 2024-02-23 CN CN202410200210.9A patent/CN117792059B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4636910A (en) * | 1985-04-11 | 1987-01-13 | Canadian General Electric Company Limited | Varistor overvoltage protection system with temperature systems |
| CN104134981A (en) * | 2014-07-02 | 2014-11-05 | 邯郸美的制冷设备有限公司 | Overvoltage protection device for air conditioner, overvoltage protection method and air conditioner |
| CN105514942A (en) * | 2014-09-05 | 2016-04-20 | 纬创资通股份有限公司 | protection method and protection device for electronic device |
| CN105932645A (en) * | 2016-05-31 | 2016-09-07 | 联想(北京)有限公司 | Switching power supply and electronic equipment |
| CN108572689A (en) * | 2017-03-10 | 2018-09-25 | 台达电子企业管理（上海）有限公司 | Switching Power Supply, excess temperature control guard method and Poewr control method |
| CN206727876U (en) * | 2017-05-27 | 2017-12-08 | 南宁职业技术学院 | Digital step-down switching power supply device |
| CN213342041U (en) * | 2020-11-17 | 2021-06-01 | 东莞市川信电子科技有限公司 | Programmable temperature setting power supply circuit |
| CN114034913A (en) * | 2021-11-18 | 2022-02-11 | 广东电网有限责任公司 | Method, device and system for measuring overvoltage of lightning intrusion wave of transformer substation |
| CN116885828A (en) * | 2023-09-08 | 2023-10-13 | 深圳市力生美半导体股份有限公司 | Switching power supply detection circuit, power supply method, charging device, and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117792059B (en) | 2024-05-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7719812B2 (en) | Power converters with rate of change monitoring for fault prediction and/or detection | |
| US7719808B2 (en) | Power converters with operating efficiency monitoring for fault detection | |
| US8779633B2 (en) | System and method for load control | |
| US9762133B2 (en) | AC-DC converter with output power suppression | |
| US7944086B2 (en) | System and method for load control | |
| CN107943130B (en) | Control device with current protection solid state relay | |
| US8520352B2 (en) | Multiple-channel active sensing and switching device | |
| US7940034B2 (en) | Apparatus for detecting a state of operation of a power semiconductor device | |
| CN108895634B (en) | Compressor control method and device | |
| CN117792059B (en) | Overvoltage protection method, control device and switching power supply | |
| JP2010193627A (en) | Lifetime detection device and lifetime detection method | |
| US8571832B2 (en) | Approach for monitoring energy consumption and preventive maintenance of a system based on control loop efficiency | |
| JP6201825B2 (en) | Power converter | |
| CN113133332B (en) | Controller for DC/DC converter | |
| WO2008139285A2 (en) | Power converters with component stress monitoring for fault prediction | |
| KR20170030725A (en) | Method and system for protecting over current | |
| US10250147B2 (en) | Switched-mode power supply and method for operating a switched-mode power supply | |
| CN112583265B (en) | DCDC power supply control method and control system thereof | |
| CN112398095B (en) | Constant-current charging protection circuit | |
| CN118760329A (en) | Self-learning pre-judging voltage compensation method, system, terminal equipment and storage medium | |
| CN113606735B (en) | Intelligent control method of air conditioner | |
| KR102049398B1 (en) | Linear Mode DC Power Supply Device | |
| CN118671562A (en) | Integrated circuit performance monitoring control system and method based on Internet of things | |
| CN118611205A (en) | Energy storage state monitoring method, energy storage management system and computer program product | |
| JP2009254094A (en) | Dc-dc converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |