CN113472190B - Low-temperature starting method of switching power supply and switching power supply - Google Patents
Low-temperature starting method of switching power supply and switching power supply Download PDFInfo
- Publication number
- CN113472190B CN113472190B CN202110655257.0A CN202110655257A CN113472190B CN 113472190 B CN113472190 B CN 113472190B CN 202110655257 A CN202110655257 A CN 202110655257A CN 113472190 B CN113472190 B CN 113472190B
- Authority
- CN
- China
- Prior art keywords
- power supply
- switching power
- temperature
- output voltage
- voltage
- 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.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/36—Means for starting or stopping converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/42—Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
- H02M1/4208—Arrangements for improving power factor of AC input
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The invention relates to a low-temperature starting method of a switching power supply and the switching power supply, which comprises the following steps: the secondary side control unit judges whether a starting up enabling signal is received or not; if yes, controlling the soft start control module to start; after the soft start control module is started, acquiring the current environment temperature; judging whether the current environment temperature is less than a preset value or not; if the current environmental temperature is less than the preset value, starting the switching power supply in a low-temperature soft start control mode; and if the current ambient temperature is greater than the preset value, starting the switching power supply in a normal-temperature soft start control mode. The invention can realize the low-temperature start of the power supply without increasing the material cost of the power supply, and has good stability, high reliability and wide application range.
Description
Technical Field
The invention relates to the technical field of switching power supplies, in particular to a low-temperature starting method of a switching power supply and the switching power supply.
Background
With the rapid development of electronic power, the requirements of electronic equipment on power supplies are higher and higher, which not only reflects the aspects of high efficiency, small volume, light weight and the like, but also more importantly requires the power supplies to have higher reliability when working in different environments. Most current switching power supplies have obvious performance reduction in low-temperature, high-temperature and humid environments.
General electronic devices are greatly influenced by temperature, especially when an electrolytic capacitor is at ultralow temperature (below-20 ℃), the equivalent resistance (ESR) of the electrolytic capacitor is increased and the capacity of the electrolytic capacitor is greatly reduced, and at the moment, when a power supply is started fully, overcurrent or overvoltage and other abnormal protection can be caused due to insufficient energy and ripples, so that the power supply cannot be started normally.
At present, it is common to perform processes on the materials of electronic components, such as increasing the capacitance of the electrolytic capacitor, using a solid capacitor with little influence of temperature, etc., which, however, increases the material cost of the power supply.
Disclosure of Invention
The present invention provides a low-temperature start method for a switching power supply and a switching power supply, which are provided to overcome the above-mentioned drawbacks of the prior art.
The technical scheme adopted by the invention for solving the technical problems is as follows: a low-temperature starting method of a switching power supply is constructed, and the method is characterized by comprising the following steps:
the secondary side control unit judges whether a starting up enabling signal is received or not;
if yes, controlling the soft start control module to start;
after the soft start control module is started, acquiring the current environment temperature;
judging whether the current environment temperature is smaller than a preset value;
if the current environment temperature is less than a preset value, starting the switching power supply in a low-temperature soft start control mode;
and if the current environment temperature is greater than a preset value, starting the switching power supply in a normal-temperature soft start control mode.
In the low-temperature starting method of the switching power supply, the method further includes:
after the switching power supply is powered on, the primary side control unit collects input voltage in real time;
the primary side control unit controls the PFC circuit according to the input voltage;
the primary side control unit monitors the PFC voltage of the PFC circuit in real time and judges whether the PFC voltage of the PFC circuit is larger than or equal to a PFC set value or not;
and if so, the primary side control unit outputs the starting-up enabling signal to the secondary side control unit.
In the low-temperature starting method of the switching power supply of the present invention, the method further includes:
if the starting-up enabling signal is received, the secondary side main control unit detects the working state of the secondary side of the switching power supply;
and if the working state of the secondary side meets the starting condition, controlling the soft starting control module to start.
In the low-temperature starting method of the switching power supply, the starting of the switching power supply in the low-temperature soft start control mode includes:
detecting the output voltage of the output end of the switching power supply in real time through an output voltage sampling module, and outputting a voltage feedback signal;
the soft start control module receives the voltage feedback signal and calculates a first frequency value for controlling the output voltage of the switching power supply according to the voltage feedback signal;
and controlling the output voltage of the switching power supply according to the first frequency value.
In the low temperature starting method of the switching power supply according to the present invention, the controlling the output voltage of the switching power supply according to the first frequency value includes:
outputting a first PWM driving signal according to the first frequency value;
controlling the working frequency of a DC-DC module through the first PWM driving signal;
monitoring the real-time output voltage of the switching power supply;
judging whether the real-time output voltage of the switching power supply is equal to a low-temperature starting voltage value or not;
and if so, controlling the output voltage of the switching power supply to keep the current voltage for a preset time.
In the low-temperature starting method of the switching power supply, the method further includes:
when the output voltage of the switching power supply keeps the current voltage for the preset time, adjusting and controlling the frequency value of the output voltage of the switching power supply;
and controlling the output voltage of the switching power supply according to the adjusted frequency value for controlling the output voltage of the switching power supply.
In the low temperature starting method of the switching power supply according to the present invention, after controlling the output voltage of the switching power supply according to the adjusted frequency value for controlling the output voltage of the switching power supply, the method includes:
continuously monitoring the real-time output voltage of the switching power supply to obtain a real-time voltage value of the switching power supply;
judging whether the real-time voltage value is equal to a target voltage value or not;
if so, completing the low-temperature starting of the switching power supply;
if not, continuously controlling the output voltage of the switching power supply according to the adjusted frequency value for controlling the output voltage of the switching power supply.
In the low-temperature starting method of the switching power supply, the starting of the switching power supply by adopting the normal-temperature soft start control module comprises the following steps:
detecting the output voltage of the output end of the switching power supply in real time through an output voltage sampling module, and outputting a voltage feedback signal;
the soft start control module receives the voltage feedback signal and calculates a second frequency value for controlling the output voltage of the switching power supply according to the voltage feedback signal;
and controlling the output voltage of the switching power supply according to the second frequency value.
In the low temperature starting method of the switching power supply according to the present invention, after the controlling the output voltage of the switching power supply according to the second frequency value, the method includes:
continuously monitoring the real-time output voltage of the switching power supply to obtain a real-time voltage value of the switching power supply;
judging whether the real-time voltage value is equal to a target voltage value or not;
if so, completing the low-temperature starting of the switching power supply;
if not, the output voltage of the switching power supply is continuously controlled according to the adjusted frequency value for controlling the output voltage of the switching power supply.
The present invention also provides a switching power supply, comprising: the device comprises a primary side control unit, a secondary side control unit and a temperature detection module;
the primary side control unit is used for outputting a starting-up enabling signal to the secondary side control unit;
the temperature detection module is used for detecting the ambient temperature of the switching power supply and outputting an ambient temperature detection signal;
the secondary side control unit is communicated with the temperature detection module and the primary side control unit, and is used for executing according to the environment temperature detection signal after receiving the starting-up enabling signal:
judging whether the current environment temperature is less than a preset value;
if the current environment temperature is less than a preset value, starting the switching power supply in a low-temperature soft start control mode;
and if the current ambient temperature is greater than the preset value, starting the switching power supply in a normal-temperature soft start control mode.
In the switching power supply of the present invention, the switching power supply further includes: the device comprises a rectification circuit, a PFC circuit, an input voltage sampling circuit, a PFC voltage sampling circuit and a DC-DC circuit;
the input end of the rectification circuit receives an alternating current signal, the output end of the rectification circuit is connected with the input end of the PFC circuit, and the rectification circuit is used for rectifying the alternating current signal and outputting a direct current signal to the PFC circuit;
the output end of the PFC circuit is connected with the input end of the DC-DC circuit, the output end of the DC-DC circuit is the output end of the switching power supply, the control end of the PFC circuit is connected with the primary side control unit, and the PFC circuit is used for performing PFC voltage conversion and outputting PFC voltage according to a PFC control signal output by the primary side control unit;
the input voltage sampling circuit is used for sampling an alternating current signal and outputting an input voltage sampling signal to the primary side control unit;
the PFC voltage sampling circuit is used for sampling PFC voltage output by the PFC circuit and outputting a PFC voltage feedback signal to the primary side control unit;
the primary side control unit performs closed-loop control on the PFC circuit according to the input voltage sampling signal and the PFC voltage feedback signal so as to control the PFC voltage of the PFC circuit to reach a set value, and outputs the startup enabling signal when the PFC voltage of the PFC circuit reaches the set value.
In the switching power supply of the present invention, the switching power supply further includes: an output voltage sampling module; the secondary control unit includes: the device comprises a temperature calculation module, an output voltage feedback module, a soft start control module, a low-temperature soft start module, a normal-temperature soft start module and a PWM (pulse width modulation) driving module;
the output voltage sampling module is used for detecting the output voltage of the output end of the switching power supply in real time and outputting a voltage feedback signal;
the output voltage feedback module is connected with the output voltage sampling module and used for receiving the output voltage feedback signal, processing the output voltage feedback signal and transmitting the processed output voltage feedback signal to the soft start control module;
the temperature calculation module is connected with the temperature detection module and used for receiving the environment temperature detection signal, processing the environment temperature detection signal and outputting the current environment temperature to the soft start control module;
the soft start control module is respectively connected with the temperature calculation module and the output voltage feedback module, and is used for controlling the low-temperature soft start module to start or controlling the normal-temperature soft start module to start according to the current environment temperature so as to control the low-temperature soft start module to output a low-temperature soft start signal to the PWM driving module or control the normal-temperature soft start module to output a normal-temperature soft start signal to the PWM driving module;
and the PWM driving module controls the DC-DC circuit according to the low-temperature soft start signal or the normal-temperature soft start signal.
The low-temperature starting method of the switching power supply and the switching power supply have the following beneficial effects: the method comprises the following steps: the secondary side control unit judges whether a starting up enabling signal is received or not; if yes, controlling the soft start control module to start; after the soft start control module is started, acquiring the current environment temperature; judging whether the current environment temperature is less than a preset value; if the current environmental temperature is less than the preset value, starting the switching power supply in a low-temperature soft start control mode; and if the current ambient temperature is greater than the preset value, starting the switching power supply in a normal-temperature soft start control mode. The invention can realize the low-temperature start of the power supply without increasing the material cost of the power supply, and has good stability, high reliability and wide application range.
Drawings
The invention will be further described with reference to the accompanying drawings and examples, in which:
fig. 1 is a schematic flow chart of a low-temperature startup method of a switching power supply according to an embodiment of the present invention;
fig. 2 is a schematic flow chart of starting the switching power supply by using the low-temperature soft start control mode according to the embodiment of the present invention;
fig. 3 is a schematic flow diagram of starting the switching power supply by using a normal-temperature soft start control mode according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of curves of low-temperature start and normal-temperature start provided by an embodiment of the present invention;
FIG. 5 is a functional block diagram of a switching power supply provided by an embodiment of the present invention;
fig. 6 is a schematic block diagram of a secondary side control unit according to an embodiment of the present invention.
Detailed Description
For a more clear understanding of the technical features, objects, and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
Referring to fig. 1, a schematic flow chart of an alternative embodiment of a low-temperature startup method of a switching power supply provided by the present invention is shown. The low-temperature starting method of the switching power supply can be suitable for starting the electrolytic capacitor at ultralow temperature (such as below-20 ℃), and abnormal protection such as overcurrent or overvoltage caused by insufficient energy and overlarge ripple waves can not be generated by adopting the low-temperature starting method, so that the switching power supply can be normally started, and the low-temperature starting method can be suitable for the electrolytic capacitor with lower price, can not increase the material cost of the switching power supply, and has good stability and high reliability.
Specifically, as shown in fig. 1, the method for starting the switching power supply at a low temperature is characterized by comprising the following steps:
in step S11, the secondary control unit 108 determines whether a power-on enable signal is received.
In some embodiments, step S11 is preceded by:
step S101, after the switching power supply is powered on, the primary side control unit 106 collects the input voltage in real time.
In step S102, the primary side control unit 106 controls the PFC circuit 102 according to the input voltage.
Step S103, the primary side control unit 106 monitors the PFC voltage of the PFC circuit 102 in real time, and determines whether the PFC voltage of the PFC circuit 102 is greater than or equal to a PFC set value.
Step S104, if yes, the primary side control unit 106 outputs a power-on enable signal to the secondary side control unit 108.
It can be understood that, after the switching power supply is powered on, the primary side control unit 106 implements closed-loop control on the PFC circuit 102 by sampling the input voltage and the PFC voltage of the PFC circuit 102 to control the output voltage (PFC voltage) of the PFC circuit 102 to reach a set value, and when the PFC voltage of the PFC circuit 102 reaches the set value (i.e., is greater than or equal to the set value), outputs a power-on enable signal to the secondary side control unit 108.
And S12, if so, controlling the soft start control module 1083 to start.
In some embodiments, before step S12, the method further includes:
step S12-01, if the power-on enable signal is received, the secondary control unit 108 detects the working state of the secondary side of the switching power supply. The working state of the secondary side includes, but is not limited to, the temperature of the secondary side, a given signal of an external system, a control signal of the system itself, and the like. For example, if the temperature is too high, the secondary side does not start the output at this time. Or, the given signal of the external system or the control signal of the system itself requires that the system cannot be started, and the secondary side does not start the output at this time.
And S12-02, if the working state of the secondary side meets the starting condition, controlling a soft start control module 1083 to start. Optionally, the start-up condition includes, but is not limited to, that the temperature is lower than a preset temperature (the preset temperature is set according to the requirement of the product), and that a given signal of the external system or a control signal of the system itself is allowable to start up.
In the embodiment of the present invention, after the secondary side control unit 108 receives the power-on enable signal sent by the primary side control unit 106, the flag bit (Bulk _ OK) of the secondary side is set to 1, and meanwhile, the working state of the secondary side is determined, and if there is no exception, the soft start control module 1083 is controlled to start.
Step S13, after the soft start control module 1083 is started, the current ambient temperature is acquired.
Specifically, after the soft start control module 1083 is started, the ambient temperature of the switching power supply is detected by the temperature detection module 110, and a corresponding ambient temperature detection signal is output. The ambient temperature detection signal is transmitted to the secondary control unit 108 in real time, and the secondary control unit 108 converts the ambient temperature detection signal into corresponding temperature data, so as to obtain the current ambient temperature.
And S14, judging whether the current environment temperature is less than a preset value.
Optionally, in the embodiment of the present invention, the preset value may be-20 ℃.
And S15, if the current environment temperature is less than a preset value, starting the switching power supply in a low-temperature soft start control mode.
In some embodiments, as shown in fig. 2, if the current ambient temperature of the switching power supply is less than the preset value, the switching power supply is started in the low-temperature soft-start control mode, where starting the switching power supply in the low-temperature soft-start control mode includes:
step S151, detecting the output voltage of the output end of the switching power supply in real time through the output voltage sampling module 109, and outputting a voltage feedback signal.
In step S152, the soft start control module 1083 receives the voltage feedback signal and calculates a first frequency value of the output voltage of the switching power supply according to the voltage feedback signal.
And step S153, controlling the output voltage of the switching power supply according to the first frequency value.
In some embodiments, controlling the output voltage of the switching power supply according to the first frequency value comprises: outputting a first PWM driving signal according to a first frequency value; controlling the working frequency of the DC-DC module through the first PWM driving signal; monitoring the real-time output voltage of the switching power supply; judging whether the real-time output voltage of the switching power supply is equal to a low-temperature starting voltage value or not; if yes, controlling the output voltage of the switching power supply to keep the current voltage for a preset time.
Optionally, in the embodiment of the present invention, the low-temperature start voltage value is 25V. The preset time is 1-2 minutes.
Further, when the output voltage of the switching power supply keeps the current voltage for a preset time, adjusting and controlling the frequency value of the output voltage of the switching power supply; and controlling the output voltage of the switching power supply according to the adjusted frequency value of the output voltage of the switching power supply.
Further, in some embodiments, controlling the output voltage of the switching power supply according to the adjusted frequency value of the output voltage of the switching power supply comprises: continuously monitoring the real-time output voltage of the switching power supply to obtain a real-time voltage value of the switching power supply; judging whether the real-time voltage value is equal to the target voltage value or not; if so, completing the low-temperature starting of the switching power supply; if not, continuously controlling the output voltage of the switching power supply according to the adjusted frequency value for controlling the output voltage of the switching power supply.
Optionally, the target voltage value is 56V.
Specifically, when the current ambient temperature of the switching power supply is less than the preset value, the soft start control module 1083 is started, and during the starting process, the output voltage of the switching power supply is controlled by sampling the output voltage of the switching power supply and using a first frequency value (i.e., by adjusting the operating frequency of the resonant converter LLC and the synchronous rectification SR in the DC-DC circuit 103), so that the output voltage of the switching power supply slowly climbs from 0V to 25V, and starts to time when 24V is reached, and after 1 to 2 minutes of accumulation, the frequency value of the output voltage of the switching power supply is continuously adjusted and controlled based on the real-time output voltage of the switching power supply, so that the DC-DC circuit 103 works according to the adjusted frequency value, so that the output voltage of the switching power supply slowly reaches the target voltage value, and low-temperature soft start control over of the switching power supply is realized.
After the low-temperature starting voltage value is reached, the low-temperature starting voltage value is kept (namely, the low-temperature starting voltage value is kept at 25V) for 1-2 minutes, so that a process of energy accumulation of a PFC capacitor (C1) at the output end of the PFC circuit 102 and an output capacitor at the output end of the DC-DC circuit 103 can be ensured, the activity of electrolyte of an electrolytic capacitor is increased, the energy of the capacitor is increased, and abnormal protection such as overcurrent or overvoltage caused by insufficient energy and overlarge ripple waves when a power supply is fully loaded and started is avoided.
And S16, if the current environment temperature is greater than a preset value, starting the switching power supply in a normal-temperature soft start control mode.
As shown in fig. 3, when the current ambient temperature of the switching power supply is greater than the preset value, the switching power supply does not need to be started in the low-temperature soft start control mode, and the switching power supply is directly started in the conventional soft start control mode.
Specifically, step S16, adopting the normal temperature soft start control module to start the switching power supply includes:
step S161, detecting the output voltage of the output end of the switching power supply in real time through the output voltage sampling module 109, and outputting a voltage feedback signal.
In step S162, the soft start control module 1083 receives the voltage feedback signal and calculates a second frequency value of the output voltage of the switching power supply according to the voltage feedback signal.
And step S163, controlling the output voltage of the switching power supply according to the second frequency value.
In some embodiments, controlling the output voltage of the switching power supply according to the second frequency value comprises: continuously monitoring the real-time output voltage of the switching power supply to obtain a real-time voltage value of the switching power supply; judging whether the real-time voltage value is equal to the target voltage value or not; if so, completing the low-temperature starting of the switching power supply; if not, the output voltage of the switching power supply is continuously controlled according to the adjusted frequency value of the output voltage of the switching power supply.
Specifically, as shown in fig. 4, when the current ambient temperature of the switching power supply is less than the preset value, the operating frequency of the resonant converter and the synchronous rectification in the DC-DC circuit 103 is controlled to make the output voltage of the switching power supply slowly climb from 0V to 25V and keep for 1-2 minutes, and then the operating frequency of the resonant converter and the synchronous rectification in the DC-DC circuit 103 is controlled to make the output voltage of the switching power supply slowly climb from 25V to 56V, so that overcurrent or overvoltage triggering abnormal protection of the switching power supply caused by insufficient energy of an electrolytic capacitor and excessive ripple due to full-load startup is avoided.
When the current ambient temperature of the switching power supply is greater than the preset value, the output voltage of the switching power supply can slowly climb from 0V to 56V by directly controlling the working frequency of the resonant converter and the synchronous rectification in the DC-DC circuit 103, so as to realize the conventional soft start.
Referring to fig. 5, fig. 5 is a schematic block diagram of an alternative embodiment of a switching power supply provided in the present invention. The switching power supply can realize low-temperature soft start through the low-temperature starting method of the switching power supply disclosed by the embodiment of the invention.
Specifically, as shown in fig. 5, the switching power supply may include: a primary side control unit 106, a secondary side control unit 108, and a temperature detection module 110.
The primary control unit 106 is configured to output a power-on enable signal to the secondary control unit 108.
Specifically, after the switching power supply is powered on, the primary side control unit 106 implements closed-loop control on the PFC circuit 102 by sampling the input voltage and the PFC voltage of the PFC circuit 102 to control the output voltage (PFC voltage) of the PFC circuit 102 to reach a set value, and when the PFC voltage of the PFC circuit 102 reaches the set value (i.e., is greater than or equal to the set value), outputs a power-on enable signal to the secondary side control unit 108.
The temperature detection module 110 is configured to detect an ambient temperature of the switching power supply and output an ambient temperature detection signal.
The secondary side control unit 108 is in communication with the temperature detection module 110 and the primary side control unit 106, and is configured to execute, after receiving the power-on enable signal, according to the ambient temperature detection signal:
judging whether the current environment temperature is less than a preset value or not; if the current environmental temperature is less than the preset value, starting the switching power supply in a low-temperature soft start control mode; and if the current ambient temperature is greater than the preset value, starting the switching power supply in a normal-temperature soft start control mode.
Specifically, the secondary control unit 108 selects to start the switching power supply in the low-temperature soft start control mode or the normal-temperature soft start control mode according to the current ambient temperature after receiving the power-on enable signal sent by the primary control unit 106.
Further, as shown in fig. 5, the switching power supply further includes: a rectifier circuit 101, a PFC circuit 102, an input voltage sampling circuit 105, a PFC voltage sampling circuit 104, and a DC-DC circuit 103.
The input end of the rectifier circuit 101 receives an alternating current signal, the output end of the rectifier circuit 101 is connected with the input end of the PFC circuit 102, and the rectifier circuit 101 is used for rectifying the alternating current signal and outputting a direct current signal to the PFC circuit 102.
The output end of the PFC circuit 102 is connected to the input end of the DC-DC circuit 103, the output end of the DC-DC circuit 103 is the output end of the switching power supply, the control end of the PFC circuit 102 is connected to the primary side control unit 106, and the PFC circuit 102 is configured to perform PFC voltage conversion according to a PFC control signal output by the primary side control unit 106 and output a PFC voltage.
The input voltage sampling circuit 105 is configured to sample an ac signal and output an input voltage sampling signal to the primary side control unit 106.
The PFC voltage sampling circuit 104 is configured to sample the PFC voltage output by the PFC circuit 102 and output a PFC voltage feedback signal to the primary side control unit 106.
The primary side control unit 106 performs closed-loop control on the PFC circuit 102 according to the input voltage sampling signal and the PFC voltage feedback signal to control the PFC voltage of the PFC circuit 102 to reach a set value, and outputs a power-on enable signal when the PFC voltage of the PFC circuit 102 reaches the set value.
Further, as shown in fig. 5, the switching power supply further includes: the voltage sampling module 109 is output. As shown in fig. 6, the secondary side control unit 108 includes: temperature calculation module 1082, output voltage feedback module 1081, soft start control module 1083, low temperature soft start module 1084, normal temperature soft start module 1085, and PWM drive module 1086.
The output voltage sampling module 109 is configured to detect an output voltage at an output end of the switching power supply in real time, and output a voltage feedback signal.
The output voltage feedback module 1081 is connected to the output voltage sampling module 109, and is configured to receive the output voltage feedback signal, process the output voltage feedback signal, and transmit the processed output voltage feedback signal to the soft start control module 1083.
Temperature calculation module 1082 is connected to temperature detection module 110, and is configured to receive the ambient temperature detection signal, process the ambient temperature detection signal, and output the current ambient temperature to soft start control module 1083.
Soft start control module 1083 is connected with temperature calculation module 1082 and output voltage feedback module 1081 respectively for control low temperature soft start module 1084 starts or control normal atmospheric temperature soft start module 1085 starts according to current ambient temperature, soft start module 1084 of control low temperature outputs low temperature soft start signal to PWM drive module 1086 or control normal atmospheric temperature soft start module 1085 of opening outputs normal atmospheric temperature soft start signal to PWM drive module 1086.
The PWM driving module 1086 controls the DC-DC circuit 103 according to the low temperature soft start signal or the normal temperature soft start signal.
Further, the switching power supply further includes: and the photoelectric coupler 107, wherein the photoelectric coupler 107 is arranged between the primary side control unit 106 and the secondary side control unit 108, and is used for the primary side control unit 106 and the secondary side control unit 108 to communicate.
Alternatively, in this embodiment of the present invention, the primary side control unit 106 and the secondary side control unit 108 may both use DSP processors.
Specifically, when the current environment temperature of the switching power supply is less than the preset value, the soft start control module 1083 controls the low-temperature soft start module 1084 to start, the low-temperature soft start module 1084 outputs a corresponding low-temperature soft start signal to the PWM driving module 1086 according to the control of the soft start control module 1083, and the PWM driving module 1086 controls the DC-DC circuit 103 according to the low-temperature soft start signal to adjust the working frequency of the resonant converter and the synchronous rectification in the DC-DC circuit 103, so as to achieve the purpose of adjusting the output voltage of the switching power supply, so that the output voltage of the switching power supply (i.e., the output voltage of the DC-DC) slowly climbs from 0V to 25V, and keeps for 1 to 2 minutes after reaching 25V; and after the voltage is kept for 1-2 minutes, the output voltage of the switching power supply is continuously monitored and sampled in real time, and the output voltage of the switching power supply is fed back and adjusted according to the sampled output voltage (closed-loop control), so that the output voltage of the switching power supply continuously and slowly climbs from 25V to 56V.
When the current environment temperature of the switching power supply is greater than the preset value, the low-temperature soft start module 1084 does not work, the soft start control module 1083 controls the normal-temperature soft start module 1085 to work, so that the normal-temperature soft start module 1085 outputs a corresponding normal-temperature soft start signal to the PWM driving module 1086, and the PWM driving module 1086 controls the DC-DC circuit 103 according to the low-temperature soft start signal to adjust the working frequency of the resonant converter and the synchronous rectification in the DC-DC circuit 103, thereby achieving the purpose of adjusting the output voltage of the switching power supply, and enabling the output voltage of the switching power supply to slowly climb from 0V to 56V.
It can be understood that, when the current ambient temperature of the switching power supply is lower than the preset value, the embodiment of the present invention, through the adjustment of the secondary control unit 108, enables the output voltage of the DC-DC circuit 103 to slowly ramp from 0V to 25V, and then keeps for 1 to 2 minutes, and then controls the output voltage of the DC-DC circuit 103 to slowly ramp from 25V to 56V. Compared with the existing scheme (only the PFC voltage is increased, but the DC-DC circuit 103 does not work, and only when the output voltage of the PFC circuit 102 reaches a set value, the DC-DC circuit 103 is started), the output end of the switching power supply can be effectively prevented from generating large ripples, the phenomenon that a secondary control loop is unstable due to the large ripples on the secondary side is avoided, the switching power supply can not be triggered to perform abnormal protection, and the switching power supply can be ensured to be normally started.
In addition, the existing scheme is not suitable for an electrolytic capacitor, and only a solid-state capacitor can be selected (if the existing scheme selects the electrolytic capacitor, the energy of the electrolytic capacitor can be quickly consumed when the DC-DC circuit 103 starts to work, a large ripple wave is generated, and abnormal protection of the switching power supply is triggered), so that the cost is high. Meanwhile, the invention controls the output voltage of the DC-DC output end to slowly climb to 25V, thereby avoiding the generation of larger ripple waves, ensuring the stability of a secondary control loop and improving the stability and reliability of the switching power supply.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed in the embodiment corresponds to the method disclosed in the embodiment, so that the description is simple, and the relevant points can be referred to the description of the method part.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the scope of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.
Claims (10)
1. A low-temperature starting method of a switching power supply is characterized by comprising the following steps:
the secondary side control unit judges whether a starting up enabling signal is received or not;
if yes, controlling the soft start control module to start;
after the soft start control module is started, acquiring the current environment temperature;
judging whether the current environment temperature is smaller than a preset value;
if the current environment temperature is less than a preset value, starting the switching power supply in a low-temperature soft start control mode;
if the current ambient temperature is greater than a preset value, starting the switching power supply in a normal-temperature soft start control mode;
the starting of the switching power supply by adopting the low-temperature soft start control mode comprises the following steps:
detecting the output voltage of the output end of the switching power supply in real time through an output voltage sampling module, and outputting a voltage feedback signal;
the soft start control module receives the voltage feedback signal and calculates a first frequency value for controlling the output voltage of the switching power supply according to the voltage feedback signal;
controlling the output voltage of the switching power supply according to the first frequency value;
the controlling the output voltage of the switching power supply according to the first frequency value comprises:
outputting a first PWM driving signal according to the first frequency value;
controlling the working frequency of a DC-DC module through the first PWM driving signal;
monitoring the real-time output voltage of the switching power supply;
judging whether the real-time output voltage of the switching power supply is equal to a low-temperature starting voltage value or not;
and if so, controlling the output voltage of the switching power supply to keep the current voltage for a preset time.
2. The method for starting a switching power supply at a low temperature according to claim 1, further comprising:
after the switching power supply is powered on, the primary side control unit collects input voltage in real time;
the primary side control unit controls the PFC circuit according to the input voltage;
the primary side control unit monitors the PFC voltage of the PFC circuit in real time and judges whether the PFC voltage of the PFC circuit is larger than or equal to a PFC set value or not;
and if so, the primary side control unit outputs the starting-up enabling signal to the secondary side control unit.
3. The method for starting a switching power supply at a low temperature according to claim 1, further comprising:
if the starting-up enabling signal is received, the secondary side control unit detects the working state of the secondary side of the switching power supply;
and if the working state of the secondary side meets the starting condition, controlling the soft starting control module to start.
4. The method for starting a switching power supply at a low temperature according to claim 1, further comprising:
when the output voltage of the switching power supply keeps the current voltage for the preset time, adjusting and controlling the frequency value of the output voltage of the switching power supply;
and controlling the output voltage of the switching power supply according to the adjusted frequency value for controlling the output voltage of the switching power supply.
5. The method for starting the switching power supply at a low temperature according to claim 4, wherein the controlling the output voltage of the switching power supply according to the adjusted frequency value for controlling the output voltage of the switching power supply comprises:
continuously monitoring the real-time output voltage of the switching power supply to obtain a real-time voltage value of the switching power supply;
judging whether the real-time voltage value is equal to a target voltage value or not;
if so, completing the low-temperature starting of the switching power supply;
if not, the output voltage of the switching power supply is continuously controlled according to the adjusted frequency value for controlling the output voltage of the switching power supply.
6. The method for starting the switching power supply at the low temperature according to claim 1, wherein the starting the switching power supply by using the normal-temperature soft start control module comprises:
detecting the output voltage of the output end of the switching power supply in real time through an output voltage sampling module, and outputting a voltage feedback signal;
the soft start control module receives the voltage feedback signal and calculates a second frequency value for controlling the output voltage of the switching power supply according to the voltage feedback signal;
and controlling the output voltage of the switching power supply according to the second frequency value.
7. The method for starting the switching power supply at a low temperature according to claim 6, wherein the controlling the output voltage of the switching power supply according to the second frequency value comprises:
continuously monitoring the real-time output voltage of the switching power supply to obtain a real-time voltage value of the switching power supply;
judging whether the real-time voltage value is equal to a target voltage value or not;
if so, completing the low-temperature starting of the switching power supply;
if not, the output voltage of the switching power supply is continuously controlled according to the adjusted frequency value for controlling the output voltage of the switching power supply.
8. A switching power supply, comprising: the device comprises a primary side control unit, a secondary side control unit, a temperature detection module and an output voltage sampling module; the secondary side control unit includes: a soft start control module;
the primary side control unit is used for outputting a starting-up enabling signal to the secondary side control unit;
the temperature detection module is used for detecting the ambient temperature of the switching power supply and outputting an ambient temperature detection signal;
the secondary side control unit is communicated with the temperature detection module and the primary side control unit, and is used for executing according to the environment temperature detection signal after receiving the starting-up enabling signal:
judging whether the current environment temperature is less than a preset value;
if the current environment temperature is less than a preset value, starting the switching power supply in a low-temperature soft start control mode;
if the current environment temperature is greater than a preset value, starting the switching power supply in a normal-temperature soft start control mode;
the output voltage sampling module is used for detecting the output voltage of the output end of the switching power supply in real time and outputting a voltage feedback signal;
the soft start control module receives the voltage feedback signal and calculates a first frequency value for controlling the output voltage of the switching power supply according to the voltage feedback signal;
controlling the output voltage of the switching power supply according to the first frequency value;
the controlling the output voltage of the switching power supply according to the first frequency value comprises:
outputting a first PWM driving signal according to the first frequency value;
controlling the working frequency of a DC-DC module through the first PWM driving signal;
monitoring the real-time output voltage of the switching power supply;
judging whether the real-time output voltage of the switching power supply is equal to a low-temperature starting voltage value or not;
and if so, controlling the output voltage of the switching power supply to keep the current voltage for a preset time.
9. The switching power supply according to claim 8, further comprising: the device comprises a rectification circuit, a PFC circuit, an input voltage sampling circuit, a PFC voltage sampling circuit and a DC-DC circuit;
the input end of the rectification circuit receives an alternating current signal, the output end of the rectification circuit is connected with the input end of the PFC circuit, and the rectification circuit is used for rectifying the alternating current signal and outputting a direct current signal to the PFC circuit;
the output end of the PFC circuit is connected with the input end of the DC-DC circuit, the output end of the DC-DC circuit is the output end of the switching power supply, the control end of the PFC circuit is connected with the primary side control unit, and the PFC circuit is used for carrying out PFC voltage conversion and outputting PFC voltage according to a PFC control signal output by the primary side control unit;
the input voltage sampling circuit is used for sampling an alternating current signal and outputting an input voltage sampling signal to the primary side control unit;
the PFC voltage sampling circuit is used for sampling PFC voltage output by the PFC circuit and outputting a PFC voltage feedback signal to the primary side control unit;
the primary side control unit performs closed-loop control on the PFC circuit according to the input voltage sampling signal and the PFC voltage feedback signal so as to control the PFC voltage of the PFC circuit to reach a set value, and outputs the startup enabling signal when the PFC voltage of the PFC circuit reaches the set value.
10. The switching power supply according to claim 9, wherein the secondary side control unit further comprises: the device comprises a temperature calculation module, an output voltage feedback module, a low-temperature soft start module, a normal-temperature soft start module and a PWM (pulse width modulation) driving module;
the output voltage feedback module is connected with the output voltage sampling module and used for receiving the output voltage feedback signal, processing the output voltage feedback signal and transmitting the processed output voltage feedback signal to the soft start control module;
the temperature calculation module is connected with the temperature detection module and used for receiving the environment temperature detection signal, processing the environment temperature detection signal and outputting the current environment temperature to the soft start control module;
the soft start control module is respectively connected with the temperature calculation module and the output voltage feedback module, and is used for controlling the low-temperature soft start module to start or controlling the normal-temperature soft start module to start according to the current environment temperature so as to control the low-temperature soft start module to output a low-temperature soft start signal to the PWM driving module or control the normal-temperature soft start module to output a normal-temperature soft start signal to the PWM driving module;
and the PWM driving module controls the DC-DC circuit according to the low-temperature soft start signal or the normal-temperature soft start signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110655257.0A CN113472190B (en) | 2021-06-11 | 2021-06-11 | Low-temperature starting method of switching power supply and switching power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110655257.0A CN113472190B (en) | 2021-06-11 | 2021-06-11 | Low-temperature starting method of switching power supply and switching power supply |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113472190A CN113472190A (en) | 2021-10-01 |
| CN113472190B true CN113472190B (en) | 2022-11-11 |
Family
ID=77870030
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110655257.0A Active CN113472190B (en) | 2021-06-11 | 2021-06-11 | Low-temperature starting method of switching power supply and switching power supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113472190B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114460988B (en) * | 2022-03-07 | 2023-05-02 | 重庆紫光华山智安科技有限公司 | Temperature control method, device, equipment and storage medium |
| CN117629450A (en) * | 2022-08-12 | 2024-03-01 | 长鑫存储技术有限公司 | Temperature detection control circuit and storage device |
| CN116545248B (en) * | 2023-06-28 | 2023-12-29 | 深圳市力生美半导体股份有限公司 | Low-temperature starting method of switching power supply, charging pile and power supply equipment |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101414748B (en) * | 2007-10-19 | 2013-03-06 | 深圳迈瑞生物医疗电子股份有限公司 | Method for starting control circuit and protecting power supply control chip |
| CN107919793A (en) * | 2017-12-20 | 2018-04-17 | 迈普通信技术股份有限公司 | The control circuit and control method and power circuit of a kind of switch converters |
| CN211930498U (en) * | 2020-01-21 | 2020-11-13 | 深圳市毂梁源技术有限公司 | Starting circuit, series resonance conversion device and switching power supply |
-
2021
- 2021-06-11 CN CN202110655257.0A patent/CN113472190B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113472190A (en) | 2021-10-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113472190B (en) | Low-temperature starting method of switching power supply and switching power supply | |
| EP3282549B1 (en) | Adapter and charging control method | |
| CN108521838B (en) | Adapter and charging control method | |
| CN111585308B (en) | Control method of photovoltaic rapid turn-off system and application device and system thereof | |
| CN107959421B (en) | BUCK-BOOST type direct current converter and control method thereof | |
| US20130016531A1 (en) | Power supply device and method of controlling power supply device | |
| JP2013042627A (en) | Dc power supply control device and dc power supply control method | |
| CN109845082B (en) | Power supply circuit, power supply device, and control method | |
| US20140185339A1 (en) | Power factor correction circuit | |
| US20140226368A1 (en) | Power conversion apparatus | |
| US10700540B2 (en) | DC power supply system | |
| CN112838618A (en) | Photovoltaic module shutoff device, inverter, photovoltaic rapid shutoff system and starting method thereof | |
| JP2003324848A (en) | Method and system for maintaining parallel operation | |
| CN116566197B (en) | Intelligent window conduction power taking chip and power supply circuit | |
| CN112003710B (en) | System and method for improving stability of POE receiving end | |
| EP4167454A1 (en) | Power converter analog chip and power converter | |
| JP2014007872A (en) | Charger | |
| CN116647127A (en) | Voltage converter and power supply system | |
| CN115211017A (en) | Converter and power adapter | |
| JP2004336888A (en) | Power compensation device and method therefor |
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 |