Power supply and method of operation thereof

Abstract

This invention provides a power supply and its operation method. A power conversion circuit receives and converts an input voltage into an output voltage and an output current. A detection circuit detects the input voltage and provides a detection result. A feedback circuit detects the output voltage and output current and generates a feedback signal. A reference voltage generation circuit generates a reference voltage based on the input voltage and the feedback signal. When the detection circuit confirms that the input voltage is less than a voltage threshold for a duration longer than a time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time based on the detection result. A control signal generation circuit generates a control signal according to the reference voltage within the preset holding time to control the power conversion circuit to gradually reduce the output current.

Description

Technical Field

[0001] This invention relates to a power supply, and more particularly to a power supply that improves system stability and its operation method. Background Technology

[0002] The power system is used to supply power to loads such as servers. To avoid power failures, the power system usually contains two or more power supplies connected in parallel to power the servers. For example, a redundant power system contains multiple power supplies that can power the servers individually or simultaneously.

[0003] When one of the multiple power supplies needs to be replaced, the removal of the power supply means that at least part of the input power to the power system is removed, making it unable to supply power. At the moment when these power supplies stop supplying power, there is a large voltage drop across the load corresponding to the continuously connected power supply, causing the overall power system to become unstable, and may even cause abnormal operation or shutdown of the load device.

[0004] Therefore, developing a power supply and its operation method that overcomes the above-mentioned shortcomings is an urgent need at present. Summary of the Invention

[0005] The purpose of this invention is to provide a power supply and its operating method, comprising a reference voltage generation circuit and a control signal generation circuit. When the detection circuit confirms that the input voltage is less than a voltage threshold for a duration longer than a time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time. The control signal generation circuit then uses a control signal to control the power conversion circuit to gradually reduce the output current. Therefore, by setting the power supply of this invention to reduce the output current within a preset holding time, the output current of other power supplies can correspondingly increase, and the output voltage provided by multiple power supplies remains approximately constant. This effectively reduces the voltage fluctuation at the load end when the power supply of this invention stops supplying power after the holding time, giving the power system using this power supply higher stability and safety, while ensuring the normal operation of the load device.

[0006] To achieve the above objectives, one embodiment of this invention is a power supply for parallel connection to one or more other power supplies to supply power to a load, and includes a power conversion circuit, a detection circuit, a feedback circuit, a reference voltage generation circuit, and a control signal generation circuit. The power conversion circuit receives and converts an input voltage into an output voltage and an output current. The detection circuit is connected to the input terminal of the power conversion circuit to detect the input voltage and provide the detection result. The feedback circuit is connected to the output terminal of the power conversion circuit to detect the output voltage and the output current and generate a feedback signal. The reference voltage generation circuit is connected to the power conversion circuit, the detection circuit, and the feedback circuit to generate a reference voltage based on the input voltage and the feedback signal. When the detection circuit confirms that the input voltage is less than a voltage threshold for a duration greater than a time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time based on the detection result. The control signal generation circuit is connected between the reference voltage generation circuit and the power conversion circuit to generate a control signal based on the reference voltage. When the detection circuit confirms that the input voltage is less than the voltage threshold for a period of time longer than the time threshold, the control signal generation circuit generates a corresponding control signal based on the reference voltage within a preset holding time to control the power conversion circuit to gradually reduce the output current.

[0007] To achieve the above objectives, another embodiment of this application is an operating method applied to a power supply unit, which is connected in parallel with one or more other power supplies to supply power to a load. The operating method includes the following steps: First, a power conversion circuit receives and converts an input voltage into an output voltage and an output current. Next, a detection circuit detects the input voltage and provides a detection result. Next, a feedback circuit detects the output voltage and output current and generates a feedback signal. Next, a reference voltage generation circuit generates a reference voltage based on the input voltage and the feedback signal. Next, a control signal generation circuit generates a control signal based on the reference voltage. Then, when the detection circuit confirms that the input voltage is less than a voltage threshold for a duration greater than a time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time based on the detection result, and the control signal generation circuit generates a control signal accordingly based on the reference voltage within the preset holding time to control the power conversion circuit to gradually reduce the output current. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the circuit structure of an embodiment of the power supply unit of the power system in this case;

[0009] Figure 2 for Figure 1 A detailed circuit diagram of an embodiment of the second power supply of the power system shown; and

[0010] Figure 3 for Figure 1The diagram shows waveforms of some parameters of the power system.

[0011] Explanation of reference numerals in the attached figures

[0012] 1: Power System

[0013] 11: First Master Input Terminal

[0014] 12: Second total input terminal

[0015] 13: Total Output Terminal

[0016] 21: First Input Power Supply

[0017] 22: Second input power supply

[0018] 23: Load

[0019] 3: First power supply unit

[0020] 4: Second power supply

[0021] 41: Power Conversion Circuit

[0022] 411: Input terminal

[0023] 412: Output terminal

[0024] 413: AC / DC conversion unit

[0025] 414: DC / DC conversion unit

[0026] 42: Detection circuit

[0027] 43: Reference Voltage Generation Circuit

[0028] 44: Control signal generation circuit

[0029] 45: Feedback Circuit

[0030] t1-t3: Time points

[0031] VD: Preset reference voltage value Detailed Implementation

[0032] Some typical embodiments embodying the features and advantages of this invention will be described in detail in the following description. It should be understood that this invention can have various variations in different implementations, all of which do not depart from the scope of this invention, and the descriptions and drawings herein are for illustrative purposes only and not for limiting the invention.

[0033] Please see Figures 1 to 3 ,in Figure 1 This is a circuit diagram illustrating one embodiment of the power supply unit in the power system of this case. Figure 2 for Figure 1A detailed circuit diagram of an embodiment of the second power supply of the power system shown. Figure 3 for Figure 1 The diagram shows partial parameter waveforms of the power system. The power system 1 in this case includes multiple power supplies; for ease of explanation, the following embodiment will only be described using two power supplies. When the power system 1 includes more than two power supplies, it can still operate in the same or similar manner. Figure 1 As shown, the power system 1 of this invention is connected to a first input power supply 21, a second input power supply 22, and a load 23, wherein the first input power supply 21 and the second input power supply 22 can be AC ​​power supplies or DC power supplies. In this embodiment, the first input power supply 21 and the second input power supply 22 are taken as AC power supplies.

[0034] The power supply system 1 includes a first total input terminal 11, a second total input terminal 12, a total output terminal 13, a first power supply 3, and a second power supply 4. The power supply system 1 receives a first input voltage provided by a first input power source 21 via the first total input terminal 11, and receives a second input voltage provided by a second input power source 22 via the second total input terminal 12. The first power supply 3 is connected to the first total input terminal 11 to receive and convert the first input voltage provided by the first input power source 21 into a first output voltage and a first output current. The second power supply 4 is connected to the second total input terminal 12 to receive and convert the second input voltage provided by the second input power source 22 into a second output voltage and a second output current. The first power supply 3 and the second power supply 4 are connected in parallel to supply power to the load 23 via the total output terminal 13 using both the first and second output voltages.

[0035] like Figure 2 As shown, the second power supply 4 includes a power conversion circuit 41, a detection circuit 42, a reference voltage generation circuit 43, a control signal generation circuit 44, and a feedback circuit 45. Figure 2Other components of the second power supply 4 are omitted for ease of description; however, the second power supply 4 can still have appropriate circuit components added or removed depending on different design considerations. The power conversion circuit 41 is connected between the second total input terminal 12 and the total output terminal 13, and includes an input terminal 411, an output terminal 412, an AC / DC conversion unit 413, and a DC / DC conversion unit 414. The input terminal 411 of the power conversion circuit 41 is connected to the second total input terminal 12, and the output terminal 412 of the power conversion circuit 41 is connected to the total output terminal 13. The power conversion circuit 41 receives the second input voltage provided by the second input power supply 22 via the input terminal 411, and after power conversion, outputs the second output voltage and second output current to the load 23 via the output terminal 412. The AC / DC conversion unit 413 is connected between the input terminal 411 and the DC / DC conversion unit 414, converting the AC input voltage into a DC relay voltage. The DC / DC conversion unit 414 is connected between the AC / DC conversion unit 413 and the output terminal 412, and converts the DC relay voltage into a second output voltage and a second output current in DC form.

[0036] The detection circuit 42 is connected to the input terminal 411 of the power conversion circuit 41 to detect the input voltage and provide the detection result. The feedback circuit 45 is connected to the output terminal 412 of the power conversion circuit 41 to detect the second output voltage and the second output current and generate a feedback signal. The reference voltage generation circuit 43 is connected to the detection circuit 42 and the feedback circuit 45 to confirm the input voltage based on the detection result provided by the detection circuit 42, and to generate a reference voltage accordingly based on the feedback signal generated by the feedback circuit 45. When the detection circuit 42 confirms that the input voltage is less than a voltage threshold for a duration less than or equal to a time threshold, the detection circuit 42 determines that the second input power supply 22 is normally providing power to the second power supply unit. When the reference voltage generation circuit 43 detects a decrease in the second output voltage based on the feedback signal generated by the feedback circuit 45, the control signal generation circuit 44 generates a corresponding control signal (e.g., adjusting the duty cycle of the switch control signal in the pulse width modulation signal format of the DC / DC conversion unit 414) to control the DC / DC conversion unit 414 to increase the second output voltage. When the reference voltage generation circuit 43 detects an increase in the second output voltage based on the feedback signal generated by the feedback circuit 45, the control signal generation circuit 44 generates a corresponding control signal to control the DC / DC conversion unit 414 to decrease the second output voltage. When the detection circuit 42 confirms that the input voltage is less than a voltage threshold for a duration greater than a time threshold, the detection circuit 42 determines that the second input power supply 22 is no longer normally providing power to the second power supply unit 4. Figure 3During the time interval t1 to t2, if the second input voltage of the second input power supply 22 is 0 (e.g., the second input power supply 22 and the second power supply 4 have been disconnected, or the second input power supply 22 experiences a power supply abnormality), the reference voltage generating circuit 43 will gradually reduce the reference voltage to a preset reference voltage value VD within a preset hold-up time based on the detection result of the detection circuit 42. The hold-up time is as follows: Figure 3 From time t1 to t3, the reference voltage generated by the reference voltage generation circuit 43 gradually decreases to the preset reference voltage value VD. In one embodiment, when the second input power supply 22 provides an AC input voltage of 110V and 60Hz, the voltage threshold can be set to 30V and the time threshold can be set to 2ms. In other embodiments, the voltage threshold and time threshold can be set accordingly to the power signal provided by the input power supply, so that the detection circuit 42 can determine whether the input power supply is providing power normally. The control signal generation circuit 44 is connected between the reference voltage generation circuit 43 and the DC / DC conversion unit 414 of the power conversion circuit 41. It generates a control signal based on the reference voltage provided by the reference voltage generation circuit 43 to control the operation of the DC / DC conversion unit 414 of the power conversion circuit 41. When the detection circuit 42 determines that the second input power supply 22 is normally providing power to the second power supply, and the reference voltage generation circuit 43 detects a decrease in the second output voltage based on the feedback signal generated by the feedback circuit 45, the control signal generated by the control signal generation circuit 44 controls the DC / DC conversion unit 414 to increase the second output voltage. When the reference voltage generation circuit 43 detects an increase in the second output voltage based on the feedback signal generated by the feedback circuit 45, the control signal generated by the control signal generation circuit 44 controls the DC / DC conversion unit 414 to decrease the second output voltage. When the detection circuit 42 confirms that the input voltage is less than a voltage threshold for a period of time longer than a time threshold, that is, when the detection circuit 42 determines that the second input power supply 22 is no longer normally providing power to the second power supply unit 4, the reference voltage generation circuit 43 correspondingly sets its generated reference voltage to gradually decrease to a preset reference voltage value VD, and the control signal generation circuit 44 generates a control signal to correspondingly control the DC / DC conversion unit 414 to gradually reduce the second output current, such as... Figure 3 During the time intervals t2 to t3, the output voltage jointly provided by the first power supply 3 and the second power supply 4 remains approximately constant, while the second output current of the second power supply 4 gradually decreases.

[0037] In this embodiment, the detailed circuitry within the first power supply 3 may be similar to or different from the detailed circuitry within the second power supply 4, and the second power supply 4 can operate in the manner described above.

[0038] like Figure 3As shown in the attached figure, from top to bottom, are the first input voltage received by the first power supply 3, the second input voltage received by the second power supply 4, the first output current of the first power supply 3, the second output current of the second power supply 4, the output voltage jointly provided by the first power supply 3 and the second power supply 4, and the reference voltage within the second power supply 4. As can be seen from the figure, at time t1, the second input power supply 22 is disconnected from the second power supply 4, or the second input power supply 22 experiences a power supply abnormality, i.e., the second input voltage is 0V. Between times t1 and t2, the detection circuit 42 within the second power supply 4 confirms that the second input power supply 22 is no longer normally providing power to the second power supply 4 (for example, in the aforementioned embodiment, the duration of the second input voltage being less than the voltage threshold of 30V is greater than the time threshold of 2ms), and controls the reference voltage within the second power supply 4 to begin decreasing. Between time t2 and t3, the reference voltage generating circuit 43 correspondingly sets its generated reference voltage to gradually decrease to a preset reference voltage value VD, causing the second output current of the second power supply 4 to decrease, while the first output current of the first power supply 3 increases accordingly. The output voltage jointly provided by the first power supply 3 and the second power supply 4 remains approximately unchanged. After time t3, when the second power supply 4 completely stops supplying power, the output voltage jointly provided by the first power supply 3 and the second power supply 4 experiences only a short-term and small-range voltage drop.

[0039] In the above embodiments, the control signal generation circuit 44 generates a control signal based on the increase of the reference voltage to control the power conversion circuit 41 to correspondingly increase the output voltage and / or output current, and generates a control signal based on the decrease of the reference voltage to control the power conversion circuit 41 to correspondingly decrease the output voltage and / or output current. In another embodiment, the control signal generation circuit 44 may also be configured to control the power conversion circuit 41 to correspondingly decrease the output voltage and / or output current based on the increase of the reference voltage, and to correspondingly increase the output voltage and / or output current based on the decrease of the reference voltage. In this embodiment, when the detection circuit 42 confirms that the input voltage is less than the voltage threshold for a period of time longer than the time threshold, the reference voltage generation circuit 43 will correspondingly decrease the reference voltage to a preset reference voltage value VD within a preset holding time according to the detection result. The control signal generation circuit 44 generates a control signal corresponding to the gradually increasing reference voltage value within the preset holding time to control the power conversion circuit 41 to gradually decrease the output current.

[0040] In summary, the power supply of this invention includes a reference voltage generation circuit and a control signal generation circuit. When the detection circuit confirms that the input voltage is less than the voltage threshold for a period of time longer than the time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time. This allows the control signal generation circuit to use the control signal to control the power conversion circuit to gradually reduce the output current. Therefore, compared to traditional power systems where the power supply experiences a large voltage drop after power is cut off, this power system, by setting the power supply in this invention to reduce the output current within a preset holding time, allows the output current of other power supplies to increase accordingly. Furthermore, the output voltage provided by multiple power supplies remains approximately constant. This effectively reduces the voltage fluctuation at the load end when the power supply in this invention stops supplying power after the holding time. Consequently, the power system using this power supply has advantages in terms of higher stability and safety, while ensuring the normal operation of the load device.

Claims

1. A power supply for parallel connection with one or more other power supplies to supply power to a load, comprising: A power conversion circuit is used to receive and convert input voltage into output voltage and output current; A detection circuit, connected to the input terminal of the power conversion circuit, is used to detect the input voltage and provide the detection result; A feedback circuit, connected to the output terminal of the power conversion circuit, is used to detect the output voltage and the output current, and generate a feedback signal. A reference voltage generation circuit is connected to the power conversion circuit, the detection circuit, and the feedback circuit to generate a reference voltage based on the input voltage and the feedback signal. When the detection circuit confirms that the input voltage is less than a voltage threshold for a duration longer than a time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time based on the detection result. as well as A control signal generation circuit is connected between the reference voltage generation circuit and the power conversion circuit to generate a control signal based on the reference voltage. When the detection circuit confirms that the input voltage is less than the voltage threshold for a duration longer than the time threshold, the control signal generation circuit generates the control signal corresponding to the reference voltage within the preset holding time to control the power conversion circuit to gradually reduce the output current.

2. The power supply according to claim 1, wherein the reference voltage generating circuit gradually reduces the reference voltage to a preset reference voltage value within the preset holding time according to the detection result.

3. The power supply according to claim 1, wherein the reference voltage generating circuit gradually increases the reference voltage to a preset reference voltage value within the preset holding time according to the detection result.

4. The power supply according to claim 1, wherein when the detection circuit confirms that the input voltage is less than the voltage threshold for a time period less than or equal to the time threshold, and the reference voltage generating circuit detects that the output voltage has decreased based on the feedback signal generated by the feedback circuit, the reference voltage is set to increase, and the control signal generated by the control signal generating circuit controls the power conversion circuit to increase the output voltage.

5. The power supply according to claim 1, wherein when the detection circuit confirms that the input voltage is less than the voltage threshold for a time period less than or equal to the time threshold, and the reference voltage generating circuit detects that the output voltage has increased based on the feedback signal generated by the feedback circuit, the reference voltage is set to decrease, and the control signal generated by the control signal generating circuit controls the power conversion circuit to decrease the output voltage.

6. The power supply according to claim 1, wherein the power conversion circuit includes an AC / DC conversion unit and a DC / DC conversion unit, the AC / DC conversion unit being connected between the input terminal and the DC / DC conversion unit to convert the AC input voltage into a DC relay voltage, and the DC / DC conversion unit being connected between the AC / DC conversion unit and the output terminal to convert the DC relay voltage into the DC output voltage and the output current.

7. An operating method applied to a power supply, the power supply being connected in parallel with one or more other power supplies to supply power to a load, wherein the operating method comprises: The power conversion circuit receives and converts the input voltage into output voltage and output current. The detection circuit detects the input voltage and provides the detection result; The feedback circuit detects the output voltage and the output current, and generates a feedback signal; The reference voltage generation circuit generates a reference voltage based on the input voltage and the feedback signal; The control signal generation circuit generates a control signal based on the reference voltage; as well as When the detection circuit confirms that the input voltage is less than the voltage threshold for a period of time longer than the time threshold, the reference voltage generation circuit adjusts the reference voltage accordingly within a preset holding time based on the detection result. The control signal generation circuit generates the control signal according to the reference voltage within the preset holding time to control the power conversion circuit to gradually reduce the output current.

8. The operating method according to claim 7, wherein the operating method further comprises: When the detection circuit confirms that the duration of the time during which the input voltage is less than the voltage threshold is greater than the time threshold, the reference voltage generation circuit gradually reduces the reference voltage to a preset reference voltage value within the preset holding time according to the detection result.

9. The operating method according to claim 7, wherein the operating method further comprises: When the detection circuit confirms that the duration of the time during which the input voltage is less than the voltage threshold is greater than the time threshold, the reference voltage generation circuit gradually increases the reference voltage to a preset reference voltage value within the preset holding time according to the detection result.

10. The operating method according to claim 7, wherein the operating method further comprises: When the detection circuit confirms that the input voltage is less than the voltage threshold for a period of time that is less than or equal to the time threshold, and the reference voltage generation circuit detects that the output voltage has decreased based on the feedback signal generated by the feedback circuit, the reference voltage is set to increase, and the control signal generated by the control signal generation circuit controls the power conversion circuit to increase the output voltage.

11. The operating method according to claim 7, wherein the operating method further comprises: When the detection circuit confirms that the input voltage is less than the voltage threshold for a duration less than or equal to the time threshold, and the reference voltage generation circuit detects an increase in the output voltage based on the feedback signal generated by the feedback circuit, the reference voltage is set to decrease, and the control signal generated by the control signal generation circuit controls the power conversion circuit to decrease the output voltage.

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