Overpower Protection Control Method for Switching Power Supply

Abstract

The present application relates to a method for controlling over-power protection of a switching power supply, which includes: obtaining the peak value of the input voltage within a set time before the current moment; adjusting the trigger voltage value of the over-power protection based on the peak value of the input voltage, and the trigger voltage value is negatively correlated with the peak value of the input voltage; obtaining the input voltage value in real time; triggering over-power protection when the input voltage value is greater than the trigger voltage value. By dynamically adjusting the trigger voltage value based on the peak value of the input voltage, and the trigger voltage value is negatively correlated with the peak value of the input voltage, so as to tend to make the input voltage value greater than the trigger voltage value, and then trigger over-power protection, which is beneficial to ensuring the protection effect of the switching power supply.

Description

Technical Field

[0001] This application relates to the field of switching power supplies, and in particular, to a method for controlling over-power protection of a switching power supply. Background Art

[0002] A switching power supply is a power supply device, such as a charger or a power adapter. The switching power supply is used to convert the power supply to provide appropriate power to an electronic device or other load. Generally, the input of the switching power supply is an AC power supply (such as mains power) or a DC power supply, and the output is a device that requires a DC power supply, such as a personal computer.

[0003] Currently, a general switching power supply generally includes at least one of the following protection mechanisms: over-voltage protection, over-temperature protection, and over-power protection, etc.

[0004] Generally, over-power protection is to set a voltage threshold and / or a current threshold. When the voltage value is greater than the voltage threshold and / or the current value is greater than the current threshold, over-power protection is triggered to protect the switching power supply.

[0005] When the input of the switching power supply is mains power, the voltage may fluctuate, and the over-power protection mechanism based on a fixed voltage threshold cannot provide effective protection. Summary of the Invention

[0006] In order to ensure the protection effect of the over-power protection mechanism on the switching power supply, this application provides a method for controlling over-power protection of a switching power supply.

[0007] A method for controlling over-power protection of a switching power supply provided by this application adopts the following technical solutions:

[0008] A method for controlling over-power protection of a switching power supply includes:

[0009] Obtain the peak value of the input voltage within a set time before the current moment;

[0010] Adjust the trigger voltage value of the over-power protection based on the peak value of the input voltage, and the trigger voltage value is negatively correlated with the peak value of the input voltage;

[0011] Obtain the input voltage value in real time;

[0012] When the input voltage value is greater than the trigger voltage value, trigger over-power protection.

[0013] By adopting the above technical solutions, the trigger voltage value is dynamically adjusted based on the peak value of the input voltage, and the trigger voltage value is negatively correlated with the peak value of the input voltage, so as to tend to make the input voltage value greater than the trigger voltage value, and then trigger over-power protection, which is beneficial to ensuring the protection effect on the switching power supply.

[0014] Preferably, it further includes:

[0015] Obtain over - power protection information, where the over - power protection information includes the maximum value of the single - trigger duration of over - power protection within a preset time before the current moment;

[0016] Adjust the set time based on the over - power protection information, and the set time is positively correlated with the maximum value of the single - trigger duration.

[0017] By adopting the above - mentioned technical solution, in the case of triggering over - power protection, there may be a situation where the input voltage value is greater than the trigger voltage value; at this time, based on the maximum value of the single - trigger duration, the set time is dynamically adjusted, and the set time is positively correlated with the maximum value of the single - trigger duration, so as to tend to increase the time of a specific input voltage peak (specific input voltage peak: the input voltage peak when the input voltage value may trigger over - power protection), so as to tend to reduce the trigger voltage value, making the over - power protection easily triggered, which is beneficial to ensuring the protection effect of the switching power supply.

[0018] Preferably, it further includes:

[0019] In the case where the maximum value of the single - trigger duration is greater than the set time, adjust the set time to be equal to the maximum value of the single - trigger duration.

[0020] By adopting the above - mentioned technical solution, the positive correlation between the set time and the maximum value of the single - trigger duration is achieved.

[0021] Preferably, it further includes:

[0022] The set time is less than or equal to the preset time.

[0023] By adopting the above - mentioned technical solution, there is a direct correlation between the input voltage peak and the over - power protection information, which is beneficial to accurately adjusting the trigger voltage value and reducing the probability of mis - triggering over - power protection.

[0024] Preferably, it further includes:

[0025] Obtain over - power protection information, where the over - power protection information includes the number of trigger times of over - power protection within a preset time before the current moment;

[0026] Adjust the trigger voltage value based on the over - power protection information, and the trigger voltage value is negatively correlated with the number of trigger times.

[0027] By adopting the above - mentioned technical solution, the more the number of trigger times, the more frequent the voltage fluctuation is considered; at this time, based on the number of trigger times, the trigger voltage value is dynamically adjusted, and the trigger voltage value is negatively correlated with the number of trigger times, so as to tend to make the input voltage value greater than the trigger voltage value, and then trigger over - power protection, which is beneficial to ensuring the protection effect of the switching power supply.

[0028] Preferably, it further includes:

[0029] Initialize the trigger voltage value when the number of triggers is less than or equal to the preset number value.

[0030] By adopting the above technical solution, when the number of triggers is less than or equal to the preset number value, it is considered that the voltage is relatively stable, which is conducive to the normal operation of the switching power supply; at this time, the trigger voltage value is initialized to tend to reduce the probability of triggering over-power protection.

[0031] Preferably, it further includes:

[0032] Obtain the input current value in real time;

[0033] Trigger over-power protection when the input current value is greater than the trigger current value.

[0034] By adopting the above technical solution, trigger over-power protection is realized when the input voltage value is greater than the trigger voltage value and / or the input current value is greater than the trigger current value, providing protection for the switching power supply.

[0035] Preferably, it further includes:

[0036] Obtain over-power protection information, where the over-power protection information includes the cumulative trigger duration of over-power protection within a preset time before the current moment;

[0037] Adjust the trigger current value of over-power protection based on the over-power protection information, and the trigger current value is positively correlated with the cumulative trigger duration.

[0038] By adopting the above technical solution, compared with the breakdown of electronic components caused by too high voltage, the influence of heat generated by a relatively high current in a short time on electronic components is lower. Then, the trigger current value is dynamically adjusted based on the cumulative trigger duration to allow a relatively high current in a short time, thereby reducing the probability of triggering over-power protection due to a relatively high current.

[0039] In summary, the present application includes at least one of the following beneficial technical effects:

[0040] 1. Dynamically adjust the trigger voltage value based on the peak value of the input voltage, and the trigger voltage value is negatively correlated with the peak value of the input voltage, so as to tend to make the input voltage value greater than the trigger voltage value, thereby triggering over-power protection, which is conducive to ensuring the protection effect on the switching power supply;

[0041] 2. When over - power protection is triggered, there may be a situation where the input voltage value is greater than the trigger voltage value. At this time, based on the maximum value of the single - trigger duration, the set time is dynamically adjusted, and the set time is positively correlated with the maximum value of the single - trigger duration, so as to tend to increase the time of a specific input voltage peak (specific input voltage peak: the input voltage peak when the input voltage value may trigger over - power protection), so as to tend to reduce the trigger voltage value, making the over - power protection easier to be triggered, which is beneficial to ensuring the protection effect of the switching power supply.

[0042] 3. The more the number of trigger times, the more frequent the voltage fluctuation is considered. At this time, based on the number of trigger times, the trigger voltage value is dynamically adjusted, and the trigger voltage value is negatively correlated with the number of trigger times, so as to tend to make the input voltage value greater than the trigger voltage value, and then trigger over - power protection, which is beneficial to ensuring the protection effect of the switching power supply. Description of the Drawings

[0043] Figure 1 It is a flowchart of the over - power protection control method for a switching power supply.

[0044] Figure 2 It is a flowchart of adjusting the set time based on over - power protection information.

[0045] Figure 3 It is a flowchart of obtaining the input voltage peak value within the set time before the current moment.

[0046] Figure 4 It is a flowchart of adjusting the trigger voltage value based on over - power protection information and the input voltage peak value.

[0047] Figure 5 It is a flowchart of adjusting the trigger current value based on over - power protection information. Detailed Implementation Manner

[0048] The following further elaborates on this application in conjunction with the attached Figures 1-5 to make a more detailed description of this application.

[0049] Referring to Figure 1 , an over - power protection control method for a switching power supply disclosed in an embodiment of this application includes:

[0050] S10, obtaining over - power protection information.

[0051] The over - power protection information includes data such as the number of trigger times of over - power protection, the maximum value of the single - trigger duration, and the cumulative trigger duration within a preset time before the current moment. Among them, the preset time is configured by technical personnel.

[0052] For example, the current moment is T0, the preset time is t0. Before the current moment: over-power protection was triggered from T1 to T0, not triggered from T2 to T1, triggered from T3 to T2, not triggered from T4 to T3, triggered from T5 to T4, and T5 < T4 < T3 < T2 < T1 < T0;

[0053] If T0 - T3 < t0 and T0 - T4 ≥ t0, the number of trigger times is "2", the maximum value of the single-trigger duration is the maximum of "T0 - T1" and "T2 - T3", and the cumulative trigger duration is "T0 - T1 + T2 - T3";

[0054] If T0 - T4 < t0 and T0 - T5 ≥ t0, the number of trigger times is "3", the maximum value of the single-trigger duration is the maximum of "T0 - T1", "T2 - T3", and "T4 - T0 + t0", and the cumulative trigger duration is "T0 - T1 + T2 - T3 + T4 - T0 + t0";

[0055] If T0 - T1 ≥ t0, the number of trigger times is "1", the maximum value of the single-trigger duration is "t0", and the cumulative trigger duration is "t0".

[0056] S20, obtain the set time, trigger voltage value, and trigger current value.

[0057] The set time, trigger voltage value, and trigger current value are all configured by technicians. The trigger voltage value and trigger current value are both used to trigger over-power protection.

[0058] S30, adjust the set time based on the over-power protection information.

[0059] The set time is positively correlated with the maximum value of the single-trigger duration. And, the set time is less than or equal to the preset time. Preferably, the initial value of the set time configured by the technician is less than the preset time.

[0060] In one embodiment, referring to Figure 1 and Figure 2 , step S30 includes:

[0061] S31, when the maximum value of the single-trigger duration is greater than the set time, adjust the set time to be equal to the maximum value of the single-trigger duration;

[0062] S32, when the set time is greater than the maximum value of the single-trigger duration, initialize the set time.

[0063] Referring to Figure 1 , S40, obtain the peak value of the input voltage within the set time before the current moment.

[0064] In one embodiment, the input of the switching power supply is alternating current, referring toFigure 1 and Figure 3 , step S40 includes:

[0065] S41, obtaining the phase of the alternating current to determine the peak moment of the voltage peak point or voltage trough point;

[0066] S42, obtaining the input voltage at every predetermined time interval based on the peak moment and recording it as the voltage record value;

[0067] S43, obtaining multiple voltage record values within a set time before the current moment, and taking the largest one among all the voltage record values as the input voltage peak.

[0068] Wherein, the predetermined time can be set according to the period of the alternating current.

[0069] For example, if the mains supply is an alternating current of 50HZ, the predetermined time can be set to 0.1 (s). Based on the phase, the peak moment is determined as t1, then the input voltage is recorded once at t1 + 0.1 (s), t1 + 0.2 (s), t1 + 0.3 (s),... respectively as the voltage record value; meanwhile, the current moment T0 satisfies t1 + 0.6 < T0 < t1 + 0.7, and t0 = 0.5S, then a total of 5 voltage record values are recorded, and the 5 voltage record values are respectively recorded at the moments of t1 + 0.6, t1 + 0.5, t1 + 0.4, t1 + 0.3, t1 + 0.2, and the largest one among the 5 voltage record values is the input voltage peak.

[0070] Refer to Figure 1 , S50, adjusting the trigger voltage value based on the over - power protection information and the input voltage peak.

[0071] The trigger voltage value and the number of trigger times are negatively correlated, and the trigger voltage value and the input voltage peak are negatively correlated; and the adjusted trigger voltage value is less than or equal to the initial trigger voltage value (configured by the technician).

[0072] In one embodiment, refer to Figure 1 and Figure 4 , step S50 includes:

[0073] S51, when the number of trigger times is greater than the preset number value, calculating the voltage adjustment coefficient K1 based on the number of trigger times and the input voltage peak and adjusting the trigger voltage value;

[0074] S52, when the number of trigger times is less than or equal to the preset number value, initializing the trigger voltage value.

[0075] The preset number of times is configured by a technician. Preferably, the preset number of times is a non-negative integer, for example, "2" or "0." The voltage adjustment coefficient K1 = C0 / (C1+N)+C2 / (C3+U), where C0, C1, C2, and C3 are constants and can be configured by a technician. N is the number of triggers, and U is the peak input voltage. The adjusted trigger voltage value U1 = K1 × U0, where U0 is the initial trigger voltage value (configured by a technician). Furthermore, the voltage adjustment coefficient K1 ≯ 1.

[0076] Reference Figure 1 , S60, adjust the trigger current value based on the over-power protection information.

[0077] The trigger current value is positively correlated with the cumulative trigger duration; and the adjusted trigger current value is greater than or equal to the initial trigger current value (configured by a technician).

[0078] In one embodiment, referring to Figure 1 and Figure 5 , step S60 includes:

[0079] S61, when the accumulated trigger duration is less than the preset duration, calculating the current adjustment coefficient K2 based on the accumulated trigger duration and the preset time and adjusting the trigger current value;

[0080] S62 , when the accumulated triggering duration is greater than or equal to the preset duration, initializing the triggering current value.

[0081] The preset duration value is configured by a technician and is less than the preset time. The voltage adjustment coefficient K2 = (t2 + C4) / (t + C5), where C4 and C5 are constants and can be configured by a technician, t2 is the cumulative trigger duration, and t is the preset time. The adjusted trigger current value I1 = K2 × I0, where I0 is the initial trigger current value (configured by a technician). At the same time, the current adjustment coefficient K2 ≮ 1. In addition, the technician can adjust the values of t, C4, and C5 so that when t2 = t, the current adjustment coefficient K2 < 1.1, K2 < 1.5, K2 < 1.05, etc. should be controlled. It should be noted that in actual applications, due to the setting of the preset duration value, t2 must satisfy t2 < t.

[0082] Reference Figure 1 , S71, real-time acquisition of input voltage value and input current value;

[0083] S72: When the input voltage value is greater than the trigger voltage value and / or the input current value is greater than the trigger current value, over-power protection is triggered.

[0084] The implementation principle of a switching power supply over-power protection control method according to an embodiment of the present application is as follows: Based on the peak value of the input voltage and over-power protection information, the trigger voltage value and the trigger current value are dynamically adjusted. Moreover, the trigger voltage value is negatively correlated with the peak value of the input voltage, the trigger voltage value is negatively correlated with the number of trigger times, and the trigger current value is positively correlated with the cumulative trigger duration, so as to tend to make the input voltage value greater than the trigger voltage value, thereby triggering over-power protection, which is beneficial to ensuring the protection effect on the switching power supply.

[0085] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A switching power supply over-power protection control method, characterized in that, Including: Obtain the peak value of the input voltage within a set time before the current moment; Adjust the trigger voltage value of over-power protection based on the peak value of the input voltage, and the trigger voltage value is negatively correlated with the peak value of the input voltage; Obtain the input voltage value in real time; Trigger over-power protection when the input voltage value is greater than the trigger voltage value; Also including: Obtain over-power protection information, where the over-power protection information includes the maximum value of the single trigger duration of over-power protection within a preset time before the current moment; Adjust the set time based on the over-power protection information, and the set time is positively correlated with the maximum value of the single trigger duration; 2. The switching power supply over-power protection control method according to claim 1, wherein, Also including: When the maximum value of the single trigger duration is greater than the set time, adjust the set time to be equal to the maximum value of the single trigger duration; 3. The switching power supply over-power protection control method according to claim 1, characterized in that, Also including: The set time is less than or equal to the preset time; 4. The switching power supply over-power protection control method according to claim 1, characterized in that, Also including: Obtain over-power protection information, where the over-power protection information includes the number of trigger times of over-power protection within a preset time before the current moment; Adjust the trigger voltage value based on the over-power protection information, and the trigger voltage value is negatively correlated with the number of trigger times; 5. The switching power supply over-power protection control method according to claim 4, characterized in that, Also including: Initialize the trigger voltage value when the number of trigger times is less than or equal to the preset number of times; 6. The switching power supply over-power protection control method according to claim 1, characterized in that Also including: Obtain the input current value in real time; Trigger over-power protection when the input current value is greater than the trigger current value; 7. The switching power supply over-power protection control method according to claim 6, characterized in that, Also including: Obtain over-power protection information, where the over-power protection information includes the cumulative trigger duration of over-power protection within a preset time before the current moment; Adjust the trigger current value of over-power protection based on the over-power protection information, and the trigger current value is positively correlated with the cumulative trigger duration;

Images