Abnormal current protection device and abnormal current protection method
By introducing a short-circuit detection unit and an overcurrent detection unit into the abnormal current protection device, the problem that the traditional protection mechanism cannot detect short-circuit events in time during defibrillation is solved, and effective protection of the converter is achieved.
Patent Information
- Application Number
- CN202311076881.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-25
- Publication Date
- 2025-02-25
AI Technical Summary
The traditional overcurrent protection mechanism cannot detect and prevent short-circuit events in a timely manner during the defibrillation period during the protection cycle, resulting in the potential damage to the converter.
An abnormal current protection device is designed, including a short circuit detection unit and an overcurrent detection unit, which can detect short circuit events during the defibrillation period of the protection period and then detect overcurrent events, and make the converter or power stage through the controller. Disable to provide protection.
It effectively prevents damage to the converter by short-circuit events during the defibrillation period during the protection period, and responds to overcurrent events in a timely manner, improving protection efficiency.
Smart Images
Figure CN119518602A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to an abnormal current protection device and an abnormal current protection method. More specifically, the present disclosure relates to an abnormal current protection device and an abnormal current protection method capable of timely providing protection against a short circuit event occurring during a defibrillation period in a protection cycle. Background Art
[0002] In order to avoid the overcurrent protection being accidentally triggered due to the initial switching current, the traditional overcurrent protection mechanism is designed to ignore all abnormal current events that occur during the initial period of each protection cycle (also known as a period of debounce time or a period of blanking time). In other words, in each protection cycle, the traditional overcurrent protection mechanism will not be activated before the end of the defibrillation period. However, if a short circuit event occurs during the defibrillation period, the traditional overcurrent protection mechanism will not be able to provide protection in time, which will cause damage to the converter. In view of this, it is necessary to solve the above problem. Summary of the invention
[0003] In order to solve at least the above problems, the present disclosure provides an abnormal current protection device. The abnormal current protection device may include an overcurrent protector and a controller electrically connected to the overcurrent protector. The overcurrent protector may include a short circuit detection unit and an overcurrent detection unit. The short circuit detection unit can be used to detect whether there is a short circuit event during a defibrillation period in a protection cycle. The overcurrent detection unit can be used to detect whether there is an overcurrent event after the defibrillation period in the protection cycle. The controller can be used to: disable a converter when the short circuit event is detected, and disable a power stage when the overcurrent event is detected.
[0004] In order to solve at least the above problems, the present disclosure also provides an abnormal current protection method. The abnormal current protection method may include the following steps: an abnormal current protection device detects whether there is a short circuit event during a defibrillation period in a protection cycle; when the short circuit event is detected, the abnormal current protection device disables a converter; the abnormal current protection device detects whether there is an overcurrent event after the defibrillation period in the protection cycle; and when the overcurrent event is detected, the abnormal current protection device disables a power stage.
[0005] The abnormal current protection device provided by the present disclosure particularly includes a short circuit detection unit, which is used to detect whether there is a short circuit event during the defibrillation period in each protection cycle. Thanks to the function of the short circuit detection unit, the abnormal current protection device provided by the present disclosure will be able to detect the abnormal current caused by the short circuit during the defibrillation period in each protection cycle, thereby timely preventing the converter from being damaged.
[0006] The above content is not intended to limit the invention to be protected, and is only a preliminary description of the invention to be protected. The details of the invention to be protected will be presented later in the form of embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 A schematic diagram of an abnormal current protection device according to one or more embodiments;
[0008] Figure 2 A schematic diagram of an overcurrent protector of the abnormal current protection device;
[0009] Figure 3 A waveform diagram for presenting the protection mechanism of the overcurrent protector;
[0010] Figure 4 A schematic diagram of an overload protector of the abnormal current protection device;
[0011] Figure 5 A waveform diagram for presenting the protection mechanism of the overload protector; and
[0012] Figure 6 Schematic diagram of an abnormal current protection method according to one or more embodiments.
[0013]
Explanation of symbols
[0014] 10: Induction signal
[0015] 11: Abnormal current protection device
[0016] 111: Controller
[0017] 113: Overcurrent protector
[0018] 115: Overload protector
[0019] 12: Disability signal
[0020] 13: Converter
[0021] 131: Power Level
[0022] 14: Disability signal
[0023] 21: Short circuit detection unit
[0024] 23: Overcurrent detection unit
[0025] 25: Filter
[0026] 27: Multiplexer
[0027] 6: Abnormal current protection method
[0028] 61, 63, 65, 67: Steps
[0029] C SCP :Short-circuit capacitor
[0030] C OLP :Overload capacitor
[0031] I CS : Induction current
[0032] OCP: AND gate output
[0033] PS1: OR gate output
[0034] PS2: Comparator output
[0035] SCP: AND gate output
[0036] V CS :Induced voltage
[0037] V CS1 :First voltage
[0038] V CS2 : Second voltage
[0039] V CS3 : Third voltage
[0040] V OCP :Over current protection threshold
[0041] V OLP :Overload protection threshold
[0042] V SCP :Short circuit protection threshold DETAILED DESCRIPTION
[0043] The following embodiments are not intended to limit the invention to a specific environment, application, structure, process, or context. In the attached drawings, elements that are not directly related to the invention will be omitted. In the attached drawings, the size of the elements and the size ratio between the elements are only used as illustrative examples and are not intended to limit the invention. Unless otherwise specified, the same symbols may refer to the same elements in the case of consistency with the invention.
[0044] The terminology described herein is only for the purpose of easily describing the content of the embodiment, and is not intended to be used to limit the invention to be protected. Unless otherwise clearly indicated, the singular "one" or "a" should be deemed to include the plural. "Including", "including", "having" and other terms are used to specifically describe the existence of the features, integers, steps, operations, elements, components and / or groups stated thereafter, but do not exclude the existence or addition of one or more other additional features, integers, steps, operations, elements, components and / or groups, etc. The term "and / or" is used to represent any one or all combinations of one or more related enumerated items. When "first", "second", "third" and other terms are used to describe elements, the purpose is not to limit these described elements, but only to distinguish the described elements. Therefore, for example, without departing from the spirit or scope of the invention to be protected, the first element may also be named as the second element.
[0045] Figure 1 A schematic diagram of an abnormal current protection device according to one or more embodiments is provided, and its contents are only for illustrating the relevant embodiments, and its contents should not be regarded as any limitation on the invention to be protected.
[0046] Reference Figure 1 , the abnormal current protection device 11 may include an overcurrent protector 113 and a controller 111 electrically connected to the overcurrent protector 113. In some embodiments, the abnormal current protection device 11 may also additionally include an overload protector 115 (selective element) electrically connected to the overcurrent protector 113. Based on an induction signal 10 (induction current or induction voltage) fed back from the output end, the overcurrent protector 113 can be used to detect an overcurrent event and a short circuit event, and the overload protector 115 can be used to detect an overload event. According to the detection results of the overcurrent protector 113 and the overload protector 115, the controller 111 can be used to control the operation of a converter 13. For example, when the overcurrent protector 113 detects an overcurrent event, the controller 111 can disable a power stage 131 of the converter 13 through a disabling signal 12. In addition, when the overcurrent protector 113 detects a short circuit event, or when the overload protector 115 detects an overload event, the controller 111 may disable the entire converter 13 through another disabling signal 14 .
[0047] Figure 2 A schematic diagram of the overcurrent protector 113 of the abnormal current protection device 11 is provided, and Figure 3 A waveform diagram is provided to illustrate the protection mechanism of the overcurrent protector 113 . Figure 2 and Figure 3The contents are only for illustrating the relevant embodiments, and the contents should not be considered as any limitation to the invention to be protected.
[0048] Reference Figure 2 In some embodiments, the overcurrent protector 113 may include a short circuit detection unit 21, an overcurrent detection unit 23, a filter 25, and a multiplexer 27 electrically connected to the short circuit detection unit 21, the overcurrent detection unit 23, and the filter 25. The filter 25 may be used to define a defibrillation period for the short circuit detection unit 21 and the overcurrent detection unit 23, for example, by defining a delay time T in each protection cycle by a pulse width modulation (PWM) signal. D . By means of the function of the filter 25, the short-circuit detection unit 21 can be used to detect whether there is a short-circuit event during a defibrillation period in each protection cycle, and the overcurrent detection unit 23 can be used to detect whether there is an overcurrent event after the defibrillation period in each protection cycle. The short-circuit event may come from a short-circuit phenomenon, and the overcurrent event may come from a short-circuit phenomenon or other abnormal current phenomenon. On the other hand, the multiplexer 27 can be used to select or limit the outputs of the short-circuit detection unit 21 and the overcurrent detection unit 23, which will enable the controller 111 to control the operation of the converter 13 in a timely and appropriate manner. Various known logic gate combinations can be used to implement the above-mentioned functions of the multiplexer 27, and Figure 2 The logic gate combination shown in FIG. 1 (two AND gates and one OR gate) is provided as an illustrative example only and not as a limitation.
[0049] In some embodiments, the short circuit detection unit 21 may include a comparator for comparing a first voltage V CS1 With a short circuit protection threshold V SCP During a defibrillation period in each protection cycle, the first voltage V CS1 Greater than or equal to the short circuit protection threshold V SCP , the short circuit detection unit 21 will detect a short circuit event. CS1 is an accumulated voltage, and as shown below, the first voltage V CS1 is based on a short-circuit capacitor C SCP An induced current I CS The induction current I CS is the feedback from the output of the power stage 131:
[0050]
[0051] Among them, the induced voltage V CS is related to the induced current I CS A corresponding equivalent voltage, ie, a current-sensed voltage, is located at the output of the power stage 131 .
[0052] In some embodiments, the over-current detection unit 23 may include a comparator for comparing a second voltage V CS2 With an over-current protection threshold V OCP After a defibrillation period in each protection cycle, the second voltage V CS2 Greater than or equal to the overcurrent protection threshold V OCP , the over-current detection unit 23 will detect an over-current event. CS2 is a current sensing voltage at the output of the power stage 131, and the second voltage V CS2 is based on an inductive current I CS To calculate, where the induction current I CS is the feedback from the output of the power stage 131. In other words, the second voltage V CS2 It is an instantaneous voltage. Depending on the application, the over-current protection threshold V OCP The short circuit protection threshold V SCP Set to the same, but can also be set to different.
[0053] Also refer to Figure 2 and Figure 3 Two examples are provided below to illustrate the protection mechanism of the overcurrent protector 113. In the first example (Example 1), it is assumed that no short circuit event occurs during a defibrillation period in a protection cycle, but an overcurrent event occurs after the defibrillation period. Therefore, the AND gate output SCP will maintain a logic low during the defibrillation period, and when the current sensing voltage V CS (That is, the second voltage V CS2 ) is greater than or equal to the overcurrent protection threshold V OCP In other words, only when the current sensing voltage V CS (That is, the second voltage V CS2 ) is greater than or equal to the overcurrent protection threshold V OCPWhen the overcurrent protector 113 triggers the overcurrent protection, the controller 111 will disable the power stage 131 through the disabling signal 12. In the first example, the protection mechanism of the overcurrent protector 113 is substantially the same as the conventional overcurrent protection mechanism.
[0054] In the second example (Example 2), it is assumed that a short circuit event occurs during a defibrillation period in a protection cycle. Therefore, during the defibrillation period, when the first voltage V CS1 Greater than or equal to the short circuit protection threshold V SCP When the AND gate output SCP and the OR gate output PS1 both become logical high. CS1 Greater than or equal to the short circuit protection threshold V SCP At the beginning, the short circuit detection unit 21 has already detected the short circuit event, so unlike the traditional overcurrent protection mechanism, the overcurrent protector 113 can trigger the short circuit protection during the defibrillation period. When the overcurrent protector 113 triggers the short circuit protection, the controller 111 will disable the entire power stage 131 through the disabling signal 14 to prevent the power stage 131 from being damaged. In the disclosed short circuit protection triggering mechanism, the more severe the short circuit event is, the earlier the short circuit protection will be triggered.
[0055] Figure 4 A schematic diagram of the overload protector 115 of the abnormal current protection device 11 is provided, and Figure 5 A waveform diagram is provided to illustrate the protection mechanism of the overload protector 115 . Figure 4 and Figure 5 The contents are only for illustrating the relevant embodiments, and the contents should not be considered as any limitation to the invention to be protected.
[0056] Reference Figure 1 and Figure 4 The overload protector 115 can be used to detect whether there is an overload event spanning multiple protection cycles, and when the overload event is detected, the controller 111 can be used to disable the entire converter 13 via the disable signal 14. For example, in some embodiments, the overload protector 115 can include a comparator for comparing a third voltage V CS3 With an overload protection threshold V OLP When the third voltage V CS3 Greater than or equal to the overload protection threshold V OLP , the overload protector 115 will detect an overload event. CS3 is an accumulated voltage across multiple protection cycles, and as shown below, the third voltage V CS3is based on an overload capacitor C OLP An induced current I CS The induction current I CS is the feedback from the output of the power stage 131:
[0057]
[0058] Among them, the induced voltage V CS is related to the induced current I CS A corresponding equivalent voltage, ie, a current sensing voltage, is located at the output of the power stage 131 .
[0059] Reference Figure 4 and Figure 5 ,whenever Figure 3 The AND gate output OCP shown in FIG. 1 becomes logic high, and the inductive current I CS The overload capacitor C OLP is charged, and when the overload capacitor C OLP The voltage on (that is, the third voltage V CS3 ) is greater than or equal to the overload protection threshold V OLP When the comparator output PS2 becomes logic high, the overload protection is triggered, and the controller 111 disables the entire converter 13 via the disable signal 14. In the disclosed overload protection triggering mechanism, the more severe the overload event, the earlier the overload protection will be triggered. In addition, in the disclosed overload protection triggering mechanism, one-shot abnormal current can be filtered out, thereby preventing the overload protection from being accidentally triggered.
[0060] The converter 13 can be a recovery converter or a latch converter. Once disabled (due to the disable signal 14), the recovery converter can automatically try to restart every short period of time (called "hiccup time"), but the latch converter will remain latched until it is activated again.
[0061] Figure 6 A schematic diagram of an abnormal current protection method according to one or more embodiments is provided, and its contents are only for illustrating the relevant embodiments, and its contents should not be regarded as any limitation on the invention to be protected.
[0062] Reference Figure 6, the abnormal current protection method 6 may include the following steps: an abnormal current protection device detects whether a short circuit event exists during a defibrillation period in a protection cycle (step 61); when the short circuit event is detected, the abnormal current protection device disables a converter (step 63); the abnormal current protection device detects whether an overcurrent event exists after the defibrillation period in the protection cycle (step 65); and when the overcurrent event is detected, the abnormal current protection device disables a power stage (step 67).
[0063] In certain embodiments of the abnormal current protection method 6, the abnormal current protection device detects the short circuit event when a first voltage is greater than or equal to a short circuit protection threshold, and wherein the first voltage is calculated based on an integral of an induced current on a short circuit capacitor.
[0064] In certain embodiments of the abnormal current protection method 6 , the abnormal current protection device detects the overcurrent event when a second voltage is greater than or equal to an overcurrent protection threshold, and wherein the second voltage is calculated based on an induced current.
[0065] In some embodiments of the abnormal current protection method 6, the abnormal current protection method 6 further comprises the following steps: the abnormal current protection device detects whether there is an overload event spanning multiple protection cycles; and when the overload event is detected, the abnormal current protection device disables the converter. Regarding the implementation of overload protection, optionally, when a third voltage is greater than or equal to an overload protection threshold, the abnormal current protection device will detect the overload event, wherein the third voltage is calculated based on an integral of an inductive current on an overload capacitor.
[0066] Each embodiment of the abnormal current protection method 6 basically corresponds to a certain embodiment of the abnormal current protection device 11. Therefore, those skilled in the art to which the present invention belongs can actually fully understand and implement all corresponding embodiments of the abnormal current protection method 6 through the above description of the abnormal current protection device 11, even if all embodiments of the abnormal current protection method 6 are not described in detail above.
[0067] In the case of being consistent with the invention to be protected, even if not specifically mentioned above, various combinations, modifications or substitutions of the embodiments directly or indirectly disclosed above are substantially and completely covered by the above. The scope of protection of the invention to be protected shall be based on the claims.
Claims
1. An abnormal current protection device, comprising Overcurrent protector, including: A short circuit detection unit, used to detect whether a short circuit event occurs during the defibrillation period in the protection cycle; as well as an overcurrent detection unit, for detecting whether an overcurrent event occurs after the defibrillation period in the protection cycle; as well as The controller is electrically connected to the over-current protector and is used to disable the converter when the short-circuit event is detected and to disable the power stage when the over-current event is detected.
2. The abnormal current protection device according to claim 1, wherein: The short circuit detection unit detects the short circuit event when the first voltage is greater than or equal to the short circuit protection threshold, and wherein the first voltage is calculated based on the integration of the induced current on the short circuit capacitor.
3. The abnormal current protection device according to claim 1, wherein: The overcurrent detection unit detects the overcurrent event when the second voltage is greater than or equal to the overcurrent protection threshold, and wherein the second voltage is calculated based on the induced current.
4. The abnormal current protection device as claimed in claim 1, further comprising an overload protector electrically connected to the controller, wherein: The overload protector is used to detect whether there is an overload event spanning multiple protection cycles; as well as The controller is further configured to disable the converter when the overload event is detected.
5. The abnormal current protection device according to claim 4, wherein: The overload protector detects the overload event when the third voltage is greater than or equal to the overload protection threshold, wherein the third voltage is calculated based on the integration of the induced current on the overload capacitor.
6. The abnormal current protection device as claimed in claim 1, further comprising a filter and a multiplexer, wherein: The filter is used to define the defibrillation period; and The multiplexer is used for selecting the outputs of the short circuit detection unit and the overcurrent detection unit.
7. An abnormal current protection method, comprising: The abnormal current protection device detects whether there is a short circuit event during the defibrillation period in the protection cycle; When the short circuit event is detected, the abnormal current protection device disables the converter; By the abnormal current protection device, detecting whether there is an overcurrent event after the defibrillation period in the protection cycle; as well as When the over-current event is detected, the power stage is disabled by the abnormal current protection device.
8. The abnormal current protection method according to claim 7, wherein: The abnormal current protection device detects the short circuit event when a first voltage is greater than or equal to a short circuit protection threshold, wherein the first voltage is calculated based on an integration of an induced current on the short circuit capacitor.
9. The abnormal current protection method according to claim 7, wherein: The abnormal current protection device detects the overcurrent event when the second voltage is greater than or equal to the overcurrent protection threshold, and wherein the second voltage is calculated based on the induced current.
10. The abnormal current protection method according to claim 7, further comprising: The abnormal current protection device detects whether there is an overload event spanning multiple protection cycles; and When the overload event is detected, the converter is disabled by the abnormal current protection device.
11. The abnormal current protection method according to claim 10, wherein: The abnormal current protection device detects the overload event when the third voltage is greater than or equal to the overload protection threshold, and wherein the third voltage is calculated based on the integration of the induced current on the overload capacitor.