Power supply and control system

Abstract

A power supply includes a first conversion circuit, a second conversion circuit, a first output capacitor, a second output capacitor, a first discharge circuit, and a second discharge circuit. The first conversion circuit converts a first AC power source into a first DC power source. The second conversion circuit converts a second AC power source into a second DC power source. The first output capacitor is used to store the first DC power source. The second output capacitor is used to store the second DC power source. When the first DC power source is greater than the second DC power source, the first discharge circuit establishes a first discharge path to discharge the first output capacitor. When the second DC power source is greater than the first DC power source, the second discharge circuit establishes a second discharge path to discharge the second output capacitor.

Description

Technical Field

[0001] This invention relates to a power supply, and more particularly to a power supply with a built-in discharge circuit. Background Technology

[0002] With the advancement of technology, electronic devices are becoming increasingly diverse in type and function. Generally, an external charging device (such as an adapter) converts AC power into DC power to supply power to the electronic device. External charging devices typically have an output capacitor to store the DC power. However, the capacitance of this output capacitor is often quite large. When the external charging device stops converting AC power, a considerable voltage remains on the output capacitor, causing the electronic device to mistakenly believe that the external charging device is still supplying power and thus fail to switch to battery mode in time. Furthermore, the voltage on the output capacitor of the external charging device can easily trigger an overvoltage protection device within the electronic device, causing it to suddenly shut down. Summary of the Invention

[0003] An embodiment of the present invention provides a power supply, including a first conversion circuit, a second conversion circuit, a first output capacitor, a second output capacitor, a first discharge circuit, and a second discharge circuit. The first conversion circuit converts a first AC power supply into a first DC power supply. The second conversion circuit converts a second AC power supply into a second DC power supply. The first output capacitor stores the first DC power supply. The second output capacitor stores the second DC power supply. When the first DC power supply is greater than the second DC power supply, the first discharge circuit establishes a first discharge path to discharge the first output capacitor. When the second DC power supply is greater than the first DC power supply, the second discharge circuit establishes a second discharge path to discharge the second output capacitor.

[0004] In another embodiment, the present invention further provides a control system including a first power supply, a second power supply, and a system load. The first power supply includes a first input terminal, a first conversion circuit, a first output capacitor, a first discharge circuit, and a first output terminal. The first input terminal is used to receive a first AC power supply. The first conversion circuit converts the first AC power supply into a first DC power supply. The first output capacitor is used to store the first DC power supply. When the first DC power supply is greater than a second DC power supply, the first discharge circuit establishes a first discharge path to discharge the first output capacitor. The first output terminal is used to output the first DC power supply. The second power supply includes a second input terminal, a second conversion circuit, a second output capacitor, a second discharge circuit, and a second output terminal. The second input terminal is used to receive a second AC power supply. The second conversion circuit converts the second AC power supply into a second DC power supply. The second output capacitor is used to store the second DC power supply. When the second DC power supply is greater than the first DC power supply, the second discharge circuit establishes a second discharge path to discharge the second output capacitor. The second output terminal is used to output the second DC power supply. The system load includes a first interface and a second interface. The first interface has a first power receiving terminal and a first connection terminal. When the first output terminal is coupled to the first interface, the first power receiving terminal receives a first DC power supply, and the first connection terminal is electrically connected to a first discharge circuit. The second interface has a second power receiving terminal and a second connection terminal. The second power receiving terminal is electrically connected to the first power receiving terminal. The second connection terminal is electrically connected to the first connection terminal. When the second output terminal is coupled to the second interface, the second power receiving terminal receives a second DC power supply, and the second connection terminal is electrically connected to a second discharge circuit. Attached Figure Description

[0005] Figure 1A This is a schematic diagram of the control system of the present invention.

[0006] Figure 1B This is another schematic diagram of the control system of the present invention.

[0007] Figure 2 This is a schematic diagram of the power supply of the present invention.

[0008] Figure 3A This is a schematic diagram of the discharge circuit of the present invention.

[0009] Figure 3B This is a schematic diagram of the DC power supply of the present invention.

[0010] Figure 4A This is another schematic diagram of the discharge circuit of the present invention.

[0011] Figure 4B This is another schematic diagram of the DC power supply of the present invention.

[0012] Figure 5 This is a schematic diagram of the conversion circuit of the present invention.

[0013] Explanation of reference numerals in the attached figures:

[0014] 100A, 100B: Control System

[0015] 110, 120, 140: Power supply

[0016] 130: System Load

[0017] AC1~AC3: AC power supply

[0018] VO1~VO3: DC power supply

[0019] VAK1~VAK3: Output voltage

[0020] 131, 132, 135: Interfaces

[0021] T1, T3, T5: Power receiving terminals

[0022] T2, T4, T6: Connecting ends

[0023] 133, 134, 251-253: Wiring

[0024] 210A, 210B: Input terminals

[0025] 220A, 220B: Conversion circuit

[0026] 230A, 230B: Discharge circuit

[0027] CO21, CO22: Output capacitors

[0028] 240A, 240B: Output terminals

[0029] 241A~243A, 241B~243B: Pins

[0030] 231A, 231B: Discharge Path

[0031] GND, GND2: Grounding terminals

[0032] 241A~243A, 241B~243B: Pins

[0033] QX1, QX2, Q1~Q3: Switches

[0034] 310, 320: Impedance elements

[0035] COMP1A, COMP2A: Comparator circuits

[0036] RS1, RS2: Detection resistors

[0037] CT1, CT2: Voltage stabilizing capacitors

[0038] 510: AC-DC converter

[0039] 520: Boost circuit

[0040] 530: Step-down circuit

[0041] 540: Feedback Compensation Circuit

[0042] D1~D4, DO1~DO3: Diodes

[0043] CIN, CO1, CC, CT1, CB, CRA: Capacitors

[0044] R1, R2, RO1, RO2, RP: Resistors

[0045] PWM1, PWM2: Pulse Width Modulation Circuit

[0046] LM1, LR, LM2A: Inductors

[0047] 531: Resonant Circuit

[0048] 532: Transformer

[0049] 541: Voltage Regulator

[0050] 542: Linear Optical Coupler

[0051] N1: Primary winding

[0052] N2, N3: Secondary windings Detailed Implementation

[0053] To make the objectives, features, and advantages of this invention more apparent and understandable, specific embodiments are provided below, along with detailed descriptions in conjunction with the accompanying drawings. This specification provides different embodiments to illustrate the technical features of different implementations of the invention. The configuration of the elements in the embodiments is for illustrative purposes only and is not intended to limit the invention. Furthermore, the repetition of some reference numerals in the embodiments is for simplification and does not imply any correlation between different embodiments.

[0054] Figure 1AThis is a schematic diagram of the control system of the present invention. The control system 100A includes power supplies 110 and 120 and a system load 130. Power supplies 110 and 120 may supply power to the system load 130 individually or jointly. In this embodiment, power supply 110 receives and converts an AC power supply AC1 to generate a DC power supply VO1. In some embodiments, power supply 110 further generates an output voltage VAK1. In this example, the output voltage VAK1 is related to the DC power supply VO1. For example, the output voltage VAK1 increases as the DC power supply VO1 increases, or decreases as the DC power supply VO1 decreases.

[0055] Power supply 120 receives and converts an AC power source AC2 to generate a DC power source VO2. In some embodiments, power supply 120 generates an output voltage VAK2 based on the DC power source VO2. The output voltage VAK2 is related to the DC power source VO2. For example, the output voltage VAK2 increases as the DC power source VO2 increases, or decreases as the DC power source VO2 decreases.

[0056] In one possible embodiment, AC power supply AC1 is the same as AC power supply AC2. For example, both AC power supply AC1 and AC2 are AC mains power. In other embodiments, when DC power supply VO2 is equal to DC power supply VO1, the output voltage VAK2 is equal to the output voltage VAK1.

[0057] System load 130 has interfaces 131 and 132. Interface 131 is used to couple to power supply 110. Interface 132 is used to couple to power supply 120. When system load 130 is not coupled to power supplies 110 and 120, system load 130 enters DC mode. In DC mode, system load 130 operates based on power from a built-in rechargeable battery (not shown). In other embodiments, even when system load 130 is coupled to power supplies 110 and 120, and power supplies 110 and 120 are not receiving AC power AC1 and AC2, system load 130 still operates in DC mode.

[0058] When power supply 110 or 120 is coupled to interface 131 or 132 and receives AC power AC1 or AC2, system load 130 receives DC power VO1 or VO2 from power supply 110 or 120 and operates in an AC mode. In AC mode, system load 130 operates according to DC power VO1 or VO2. In other embodiments, when power supplies 110 and 120 are coupled to interfaces 131 and 132 respectively and receive AC power AC1 and AC2, system load 130 operates according to DC power VO1 and VO2.

[0059] Interface 131 has a power receiving terminal T1 and a connection terminal T2. Power receiving terminal T1 receives DC power VO1. Connection terminal T2 receives output voltage VAK1. Interface 132 has a power receiving terminal T3 and a connection terminal T4. Power receiving terminal T3 receives DC power VO2. Connection terminal T4 receives output voltage VAK2. In some embodiments, interfaces 131 and 132 are both power jacks, but this is not intended to limit the invention. In other embodiments, the type of interface 131 (e.g., USB Type C) differs from the type of interface 132 (e.g., power jack).

[0060] In this embodiment, the system load 130 also includes traces 133 and 134. Traces 133 are electrically connected to power receiving terminals T1 and T3. Therefore, when power supplies 110 and 120 are coupled to interfaces 131 and 132 respectively, power supplies 110 and 120 supply power to the system load 130 in parallel. Traces 134 are electrically connected to connection terminals T2 and T4. When power supplies 110 and 120 are coupled to interfaces 131 and 132 respectively and provide DC power VO1 and VO2, the output voltage VAK1 is approximately equal to the output voltage VAK2. This invention does not limit the type of system load 130. In one possible embodiment, the system load 130 is a laptop computer or a gaming PC.

[0061] The present invention does not limit the number of power supplies. In other embodiments, the control system 100A has more power supplies. Figure 1B This is another schematic diagram of the control system of the present invention. Figure 1B resemblance Figure 1A The difference is Figure 1B The control system 100B includes power supplies 110, 120 and 140.

[0062] Power supply 140 receives and converts an AC power supply AC3 to generate a DC power supply VO3. In some embodiments, the AC power supplies AC1 to AC3 are all mains power, and the DC power supplies VO1 to VO3 are all equal, such as 19.5V. In this example, the error value of each of the DC power supplies VO1 to VO3 is approximately ±5%.

[0063] In other embodiments, power supply 140 generates an output voltage VAK3 based on DC power supply VO3. The output voltage VAK3 varies with changes in DC power supply VO3. For example, when DC power supply VO3 increases, the output voltage VAK3 also increases. When DC power supply VO3 decreases, the output voltage VAK3 decreases. Since the characteristics of power supply 140 are similar to those of power supply 110, they will not be described further.

[0064] In this embodiment, the system load 130 further includes an interface 135. Interface 135 has a power receiving terminal T5 and a connection terminal T6. When the power supply 140 is coupled to interface 135, the power receiving terminal T5 receives DC power VO3, and the connection terminal T6 receives the output voltage VAK3. In this example, trace 133 is electrically connected to power receiving terminals T1, T3, and T5, and trace 134 is electrically connected to connection terminals T2, T4, and T6.

[0065] Figure 2 This is a schematic diagram of the power supplies 110 and 120 of the present invention. Since the circuit architectures of power supplies 110, 120, and 140 are identical, Figure 2 Only the circuit architecture of power supplies 110 and 120 is shown. In some embodiments, power supplies 110 and 120 are integrated into a single power supply housed in a housing.

[0066] In this embodiment, the power supply 110 includes an input terminal 210A, a conversion circuit 220A, a discharge circuit 230A, an output capacitor CO21, and an output terminal 240A. The input terminal 210A receives AC power AC1. The conversion circuit 220A converts the AC power AC1 into DC power VO1. The output capacitor CO21 is coupled to a ground terminal GND2 and stores the DC power VO1. The discharge circuit 230A is coupled to the output capacitor CO21 and generates an output voltage VAK1. The output terminal 240A outputs the DC power VO1 and the output voltage VAK1. In one possible embodiment, the output terminal 240A has pins 241A to 243A. Pin 241A receives the DC power VO1. Pin 242A is coupled to the ground terminal GND2. Pin 243A receives the output voltage VAK1. In some embodiments, the output terminal 240A is a power jack.

[0067] Power supply 120 includes an input terminal 210B, a conversion circuit 220B, a discharge circuit 230B, an output capacitor CO22, and an output terminal 240B. Input terminal 210B receives AC power AC2. Conversion circuit 220B converts AC power AC2 into DC power VO2. Output capacitor CO22 is coupled to ground GND2 and stores DC power VO2. Discharge circuit 230B is coupled to output capacitor CO22 and generates an output voltage VAK2. Output terminal 240B outputs DC power VO2 and output voltage VAK2. In one possible embodiment, output terminal 240B has pins 241B to 243B. Pin 241B receives DC power VO2. Pin 242B is coupled to ground GND2. Pin 243B receives output voltage VAK2. In some embodiments, output terminal 240B is a power plug.

[0068] In other embodiments, a system load (e.g., 130) is electrically connected to outputs 240A and 240B. In this example, the system load has traces 251 to 253. Traces 251 are electrically connected to pins 241A and 241B. Traces 252 are electrically connected to pins 242A and 242B. Traces 253 are electrically connected to pins 243A and 243B.

[0069] When power supplies 110 and 120 are normally receiving AC power AC1 and AC2, DC power VO1 is approximately equal to DC power VO2. Therefore, output voltage VAK1 is approximately equal to output voltage VAK2. However, when power supplies 110 and 120 are no longer receiving AC power AC1 and AC2, DC power VO1 will not be equal to DC power VO2, and output voltage VAK1 will not be equal to output voltage VAK2.

[0070] When DC power supply VO1 is greater than DC power supply VO2, output voltage VAK1 is greater than output voltage VAK2. Therefore, discharge circuit 230A establishes a discharge path 231A to discharge output capacitor CO21. In this example, the charge on output capacitor CO21 is released to ground GND through discharge path 231A. Therefore, DC power supply VO1 gradually decreases. When DC power supply VO2 is greater than DC power supply VO1, output voltage VAK2 is greater than output voltage VAK1. Therefore, discharge circuit 230B establishes a discharge path 231B to discharge output capacitor CO22. In this example, the charge on output capacitor CO22 is released to ground GND through discharge path 231B. Therefore, DC power supply VO2 gradually decreases.

[0071] Figure 3A This is a schematic diagram of the discharge circuits 230A and 230B of the present invention. Discharge circuit 230A includes a discharge switch QX1, an impedance element 310, a comparator circuit COMP1A, and a detection resistor RS1. The discharge switch QX1 is coupled to the output capacitor CO21. In this embodiment, the discharge switch QX1 is an N-type transistor. The impedance element 310 is coupled between the discharge switch QX1 and a ground terminal GND. In this embodiment, the impedance element 310 is a resistor. The detection resistor RS1 is coupled between the non-inverting input terminal and the inverting input terminal of the comparator circuit COMP1A. The resistance value of the detection resistor RS1 is approximately 1Ω (error value ±1%). The output terminal of the comparator circuit COMP1A is coupled to the discharge switch QX1.

[0072] The discharge circuit 230B includes a discharge switch QX2, an impedance element 320, a comparator circuit COMP2A, and a sensing resistor RS2. The discharge switch QX2 is coupled to the output capacitor CO22. In this embodiment, the discharge switch QX2 is an N-type transistor. The impedance element 320 is coupled between the discharge switch QX2 and the ground terminal GND. In this embodiment, the impedance element 320 is a resistor. The sensing resistor RS2 is coupled between the non-inverting input terminal and the inverting input terminal of the comparator circuit COMP2A. The resistance value of the sensing resistor RS2 is approximately 1Ω (with an error of ±1%). The output terminal of the comparator circuit COMP2A is coupled to the discharge switch QX2.

[0073] When DC power supply VO1 equals DC power supply VO2, since output voltage VAK1 equals output voltage VAK2, no current flows through sensing resistors RS1 and RS2. At this time, comparator circuits COMP1A and COMP2A are closed because their inverting and non-inverting input terminals are at the same potential, and discharge switches QX1 and QX2 are also cut off.

[0074] However, when DC power supply VO1 is greater than DC power supply VO2, since the voltage of voltage regulator capacitor CT1 (i.e., VAK1) is greater than the voltage of voltage regulator capacitor CT2 (i.e., VAK2), voltage regulator capacitor CT1 discharges through voltage regulator capacitor CT2. At this time, the voltage at the non-inverting input terminal of comparator circuit COMP1A is greater than the voltage at the inverting input terminal of comparator circuit COMP1A. Therefore, comparator circuit COMP1A outputs a high level to turn on discharge switch QX1. When discharge switch QX1 is turned on, discharge switch QX1 and impedance element 310 form a discharge path. The voltage VO1 of output capacitor CO21 is released to ground terminal GND through discharge switch QX1 and impedance element 310. Therefore, the voltage VO1 of output capacitor CO21 gradually decreases. At this time, since voltage regulator capacitor CT1 discharges through voltage regulator capacitor CT2, the voltage at the inverting input terminal of comparator circuit COMP2A is greater than the voltage at the non-inverting input terminal of comparator circuit COMP2A. Therefore, comparator circuit COMP2A outputs a negative saturation voltage, and discharge switch QX2 is turned off. At this time, although the output capacitor CO22 will also discharge, the discharge speed of the output capacitor CO21 is faster than that of the output capacitor CO22.

[0075] When DC power supply VO1 is less than DC power supply VO2, the voltage of voltage regulator capacitor CT2 (i.e., VAK2) is greater than the voltage of voltage regulator capacitor CT1 (i.e., VAK1), so voltage regulator capacitor CT2 discharges through voltage regulator capacitor CT1. At this time, the voltage at the non-inverting input terminal of comparator circuit COMP2A is greater than the voltage at the inverting input terminal of comparator circuit COMP2A. Therefore, comparator circuit COMP2A outputs a positive saturation voltage to turn on discharge switch QX2. When discharge switch QX2 is turned on, discharge switch QX2 and impedance element 320 form another discharge path. The voltage VO2 of output capacitor CO22 is released to ground terminal GND through discharge switch QX2 and impedance element 320. Therefore, the voltage VO2 of output capacitor CO22 gradually decreases. At this time, since voltage regulator capacitor CT2 discharges through voltage regulator capacitor CT1, the voltage at the inverting input terminal of comparator circuit COMP1A is greater than the voltage at the non-inverting input terminal of comparator circuit COMP1A. Therefore, comparator circuit COMP1A outputs a negative saturation voltage, and discharge switch QX1 is turned off. At this time, although the output capacitor CO21 will also discharge, the discharge speed of the output capacitor CO22 is faster than that of the output capacitor CO21.

[0076] In some embodiments, the voltage regulator capacitor CT1 is located in the conversion circuit 220A to power a feedback compensation circuit (not shown) within the conversion circuit 220A. In this example, the voltage regulator capacitor CT2 is located in the conversion circuit 220B to power a feedback compensation circuit (not shown) within the conversion circuit 220B.

[0077] Figure 3B This is a schematic diagram of the DC power supplies VO1 and VO2 of the present invention. Before time point T1, power supplies 110 and 120 convert AC power supplies AC1 and AC2 to generate DC power supplies VO1 and VO2. Therefore, DC power supplies VO1 and VO2 are equal and maintained at a fixed value, such as 19.5V.

[0078] After time point T1, power supplies 110 and 120 no longer receive AC power AC1 and AC2. Therefore, DC power supplies VO1 and VO2 gradually decrease. At time point T2, since DC power supply VO1 is greater than DC power supply VO2, discharge circuit 230A establishes discharge path 231A to rapidly discharge output capacitor CO21. At time point T3, since DC power supply VO2 is greater than DC power supply VO1, discharge circuit 230B establishes discharge path 231B to rapidly discharge output capacitor CO22. At time point T4, since DC power supply VO1 is greater than DC power supply VO2, discharge circuit 230A establishes discharge path 231A to rapidly discharge output capacitor CO21.

[0079] Figure 4AThis is another schematic diagram of the discharge circuits 230A and 230B of the present invention. Figure 4A resemblance Figure 3A The difference is that, Figure 4A The discharge circuits 230A and 230B utilize components of a resonant circuit within the switching circuits 220A and 220B as discharge elements. In this embodiment, when the discharge switch QX1 is turned on, the discharge switch QX1, inductor LM2A, and capacitor CRA form a discharge path. When the discharge switch QX2 is turned on, the discharge switch QX2, inductor LM2B, and capacitor CRB form a discharge path. In this example, inductor LM2A and capacitor CRA are located in switching circuit 220A, and inductor LM2B and capacitor CRB are located in switching circuit 220B.

[0080] When DC power supply VO1 is greater than DC power supply VO2, the comparator circuit COMP1A outputs a high level to turn on the discharge switch QX1. Therefore, the voltage VO1 of the output capacitor CO21 is quickly released to the ground terminal GND through the discharge switch QX1, inductor LM2A, and capacitor CRA. When DC power supply VO2 is greater than DC power supply VO1, the comparator circuit COMP2A outputs a high level to turn on the discharge switch QX2. Therefore, the voltage VO2 of the output capacitor CO22 is quickly released to the ground terminal GND through the discharge switch QX2, inductor LM2B, and capacitor CRB.

[0081] Figure 4B This is another schematic diagram of the DC power supplies VO1 and VO2 of the present invention. Before time point T5, power supplies 110 and 120 convert AC power supplies AC1 and AC2 to generate DC power supplies VO1 and VO2. Therefore, DC power supplies VO1 and VO2 are equal and maintained at a fixed value, such as 19.5V.

[0082] After time point T5, power supplies 110 and 120 no longer receive AC power AC1 and AC2. Therefore, DC power supplies VO1 and VO2 gradually decrease. At time point T6, since DC power supply VO1 is greater than DC power supply VO2, discharge circuit 230A establishes discharge path 231A to discharge output capacitor CO21. Therefore, DC power supply VO1 is released to ground GND through the resonant circuit components in conversion circuit 220A. At this time, output capacitor CO21 undergoes a resonant discharge, while output capacitor CO22 undergoes a normal discharge.

[0083] At time T7, since the DC power supply VO2 is greater than the DC power supply VO1, the discharge circuit 230B establishes a discharge path 231B to discharge the output capacitor CO22. Therefore, the DC power supply VO2 is released to the ground terminal GND through the elements of the resonant circuit in the conversion circuit 220B. At this time, the output capacitor CO22 undergoes a resonant discharge, while the output capacitor CO21 undergoes a normal discharge.

[0084] At time T8, since DC power supply VO1 is greater than DC power supply VO2, discharge circuit 230A establishes discharge path 231A to discharge output capacitor CO21. At this time, output capacitor CO21 undergoes a resonant discharge, while output capacitor CO22 undergoes a normal discharge.

[0085] Because output capacitors CO21 and CO22 discharge alternately through the inductor and capacitor, the DC power supplies VO1 and VO2 drop rapidly. Therefore, the system load (such as...) Figure 1A The 130) can switch to DC mode in real time, using the power of the built-in battery to maintain normal operation of the system load. In some embodiments, the discharge process of output capacitors CO21 and CO22 can be referred to as a self-excited rapid discharge. In addition, since the DC power supplies VO1 and VO2 drop rapidly, an overvoltage protection will not be triggered.

[0086] Figure 5 This is a schematic diagram of the conversion circuit 220A of the present invention. Since the architectures of conversion circuits 220A and 220B are similar, Figure 5 Only the architecture of the conversion circuit 220A is shown. The conversion circuit 220A includes an AC-DC converter 510, a boost circuit 520, a buck circuit 530, and a feedback compensation circuit 540.

[0087] The AC-DC converter 510 converts AC power AC1 into DC voltage V1. AC power AC1 is approximately between 90 and 264V. This invention does not limit the circuit architecture of the AC-DC converter 510. Any circuit that can convert AC power into DC power can be used as the AC-DC converter 510. In this embodiment, the AC-DC converter 510 includes diodes D1-D4 and an input capacitor CIN. Diodes D1-D4 convert AC power AC1 to generate a pulsating DC voltage. This pulsating DC voltage is then converted into a stable DC input voltage V1 via the input capacitor CIN. Diodes D1-D4 form a bridge rectifier.

[0088] In other embodiments, the conversion circuit 220A further includes resistors R1 and R2 and a pulse width modulation circuit PWM1. Resistors R1 and R2 form a voltage divider circuit. This voltage divider circuit processes the DC input voltage V1 to generate a divided voltage VCC. In this example, the divided voltage VCC serves as the operating voltage of the pulse width modulation circuit PWM1. When the pulse width modulation circuit PWM1 receives the divided voltage VCC, it generates a switching signal GD1. The switching signal GD1 is a pulse width modulation (PWM) signal.

[0089] The boost circuit 520 processes the DC input voltage V1 to generate a voltage V2. The present invention is not limited to the architecture of the boost circuit 520. Any circuit capable of boosting the DC input voltage V1 can serve as the boost circuit 520. In this embodiment, the boost circuit 520 includes a power switch Q1, a boost inductor LM1, an output diode DO1, and a boost capacitor CO1.

[0090] Power switch Q1 receives switching signal GD1 and performs high-frequency switching. In one possible embodiment, power switch Q1 is an N-type transistor. Boost inductor LM1 is coupled between resistor R1 and power switch Q1. Output diode DO1 is coupled between boost inductor LM1 and node ND1. Boost capacitor CO1 is coupled between node ND1 and ground GND. When power switch Q1 is on, boost inductor LM1 stores energy. When power switch Q1 is off, boost inductor LM1 releases energy to generate a voltage V2. Boost capacitor CO1 stores voltage V2. In one possible embodiment, voltage V2 is approximately 400V.

[0091] The buck circuit 530 processes voltage V2 to generate a DC power supply VO1. In one possible embodiment, the DC power supply VO1 is approximately 19.5V. The present invention is not limited to the architecture of the buck circuit 530. Any circuit that can reduce voltage V2 can serve as the buck circuit 530. In some embodiments, the buck circuit 530 adjusts the DC power supply VO1 according to a feedback signal FB. For example, when the voltage of the feedback signal FB decreases, the buck circuit 530 increases the DC power supply VO1. When the voltage of the feedback signal FB increases, the buck circuit 530 decreases the DC power supply VO1.

[0092] In this embodiment, the step-down circuit 530 includes a pulse width modulation circuit PWM2, switches Q2 and Q3, a resonant circuit 531, a transformer 532, and output diodes DO2 and DO3. The pulse width modulation circuit PWM2 generates switching signals GD2 and GD3 based on a feedback signal FB. Both switching signals GD2 and GD3 are pulse width modulation signals. The pulse width modulation circuit PWM2 adjusts the duty cycle of the switching signals GD2 and GD3 based on the feedback signal FB. In one possible embodiment, the switching signals GD2 and GD3 are complementary signals. Switch Q2 receives the switching signal GD2 and is coupled between nodes ND1 and ND2. Switch Q3 receives the switching signal GD3 and is coupled between node ND2 and ground GND. In one possible embodiment, switches Q2 and Q3 are both N-type transistors. Switches Q2 and Q3 operate complementaryly. For example, when switch Q2 is on, switch Q3 is not on. When switch Q3 is on, switch Q2 is not on. The resonant circuit 531 is coupled between node ND2 and ground terminal GND to generate a resonant voltage. The transformer 532 generates a DC power supply VO1 based on this resonant voltage.

[0093] In this embodiment, the resonant circuit 531 includes inductors LR and LM2A, and a resonant capacitor CRA. Inductors LR and LM2A, and resonant capacitor CRA are connected in series between node ND2 and ground terminal GND, forming an LLC resonant slot. The transformer 532 includes a primary winding N1 and secondary windings N2 and N3. The primary winding N1 is located on one side of the transformer 532, while the secondary windings N2 and N3 are located on the opposite side. The primary winding N1 is connected in parallel with inductor LM2A to receive a resonant voltage generated by the resonant circuit 531. When the primary winding N1 receives the resonant voltage, the secondary windings N2 and N3 generate induced voltages. Output diodes DO2 and DO3 rectify the induced voltages generated by the secondary windings N2 and N3, respectively. Output capacitor CO21 stores the rectification result, i.e., DC power supply VO1.

[0094] In one possible embodiment, the inductor LM2A and resonant capacitor CRA of the resonant circuit 531 serve as discharge elements to release the charge on the output capacitor CO21. For example, when the discharge switch QX1 is turned on, the charge on the output capacitor CO21 is released to the ground terminal GND through the discharge switch QX1, the inductor LM2A, and the resonant capacitor CRA.

[0095] The feedback compensation circuit 540 generates a feedback signal FB based on the DC power supply VO1. In this embodiment, the feedback compensation circuit 540 includes output resistors RO1 and RO2, a compensation capacitor CC, a voltage regulator 541, a linear optocoupler 542, a start-up resistor RP, a feedback capacitor CB, and a voltage stabilizing capacitor CT1.

[0096] Output resistors RO1 and RO2 are connected in series between the DC power supply VO1 and the ground terminal GND2. In this embodiment, output resistors RO1 and RO2 form a voltage divider circuit to divide the DC power supply VO1, thereby generating a divided voltage. The compensation capacitor CC receives the divided voltage generated by the output resistors RO1 and RO2. A voltage regulator 541 is coupled between the compensation capacitor CC and the ground terminal GND2. In this embodiment, the voltage regulator 541 has a reference terminal R, a cathode terminal K, and an anode terminal A. The reference terminal R receives the divided voltage generated by the output resistors RO1 and RO2. The cathode terminal K is coupled to the compensation capacitor CC. The anode terminal A is coupled to the ground terminal GND2. A voltage stabilizing capacitor CT1 is coupled between the compensation capacitor CC and the ground terminal GND2. In a possible embodiment, the voltage of the voltage stabilizing capacitor CT1 is used as the output voltage VAK1.

[0097] A start-up resistor RP is coupled between the output capacitor CO21 and the linear optocoupler 542. The linear optocoupler 542 generates a feedback signal FB based on the DC power supply VO1. In this embodiment, the linear optocoupler 542 has a light-emitting diode (LED) and a bipolar transistor (BPT). The LED is coupled between the start-up resistor RP and the voltage regulator capacitor CT1. The BPT and the feedback capacitor CB are connected in series between the pulse width modulation circuit PWM2 and the ground terminal GND. In this embodiment, the voltage of the feedback capacitor CB serves as the feedback signal FB.

[0098] In this embodiment, the voltage regulator 541 compares the voltage divided by the output resistors RO1 and RO2 with a preset voltage. When the voltage divided by the output resistors RO1 and RO2 differs from the preset voltage, the compensation capacitor CC adjusts the voltage gain of the circuit and generates a compensation current, illuminating the LED of the linear optocoupler 542. Finally, an induced current is coupled to the bipolar transistor of the linear optocoupler 542 through the light isolation of the LED. This induced current charges the feedback capacitor CB. Then, the pulse width modulation circuit PWM2 adjusts the duty cycles of the switching signals Q2 and Q3 according to the voltage of the feedback capacitor CB to achieve the function of stabilizing the output voltage.

[0099] In some embodiments, the power supply for the voltage regulator 541 is provided by the voltage regulator capacitor CT1. In this example, the voltage of the voltage regulator capacitor CT1 is approximately equal to the DC power supply VO1 minus the voltage of the light-emitting diode. Since the voltage of the start-up resistor RP is less than 0.05V, it can be ignored. In this embodiment, the discharge design of the voltage regulator capacitors CT1 and CT2, combined with the detection resistors RS1 and RS2 of the discharge circuit, is used to compare the output voltages VAK1 and VAK2, and then the output capacitors CO21 and CO22 are quickly discharged through the components of the LLC resonant tank.

[0100] In other embodiments, the component parameters of the conversion circuit 220A may be as follows: The input capacitor CIN has a capacitance of approximately 120uF (tolerance ±10%). The resistor R1 has a resistance of approximately 73KΩ (tolerance ±1%). The resistor R2 has a resistance of approximately 73KΩ (tolerance ±1%). The boost inductor LM1 has an inductance of approximately 660uH (tolerance ±10%). The boost capacitor CO1 has a capacitance of approximately 1500uF (tolerance ±20%). The inductor LR has an inductance of approximately 54uH (tolerance ±10%). The inductor LM2A has an inductance of approximately 480uH (tolerance ±10%). The resonant capacitor CRA has a capacitance of approximately 33nF (tolerance ±10%). The output capacitor CO21 has a capacitance of approximately 4000uF (tolerance ±20%). The voltage regulator capacitor CT1 has a capacitance of approximately 47uF (tolerance ±10%). The start-up resistor RP has a resistance of approximately 15KΩ (tolerance ±1%). The compensation capacitor CC has a capacitance of approximately 1.5nF / 50V (tolerance ±5%). The feedback capacitor CB has a capacitance of approximately 100pF / 50V (tolerance ±10%). It is important to note that the resistance, inductance, and capacitance values ​​described above are not limiting factors of this invention. Designers can adjust these values ​​according to different needs.

[0101] It is important to understand that when a component or layer is mentioned as being "coupled" to another component or layer, it can be directly coupled or connected to the other component or layer, or have other components or layers in between. Conversely, if a component or layer is "connected" to another component or layer, there will be no other components or layers in between.

[0102] Unless otherwise defined, all terms herein (including technical and scientific terms) are as commonly understood by one of ordinary skill in the art to which this invention pertains. Furthermore, unless expressly stated otherwise, definitions of terms in general dictionaries should be interpreted as consistent with their meaning in the context of their respective technical fields, and not as idealized or overly formal expressions. While terms such as "first," "second," etc., may be used to describe various elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another.

[0103] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make modifications and variations without departing from the concept and scope of the invention. For example, the systems, apparatus, or methods described in the embodiments of the present invention can be implemented in physical embodiments using hardware, software, or a combination of hardware and software. Therefore, the scope of protection of the present invention is determined by the claims.

Claims

1. A power supply, comprising: A first conversion circuit converts a first AC power supply into a first DC power supply. A second conversion circuit converts a second AC power supply into a second DC power supply. A first output capacitor is used to store the first DC power supply; A second output capacitor is used to store the second DC power supply; A first discharge circuit, when the first DC power supply is greater than the second DC power supply, establishes a first discharge path to discharge the first output capacitor. as well as A second discharge circuit is provided. When the second DC power supply is greater than the first DC power supply, the second discharge circuit establishes a second discharge path to discharge the second output capacitor.

2. The power supply of claim 1, wherein the first discharge circuit comprises: A discharge switch is coupled to the first output capacitor; An impedance element is coupled between the discharge switch and a ground terminal; as well as A comparison circuit is used to turn on the discharge switch when the first DC power supply is greater than the second DC power supply. When the discharge switch is turned on, the discharge switch and the impedance element form the first discharge path.

3. The power supply of claim 1, wherein the first conversion circuit comprises: An AC-DC converter converts the first AC power supply into a first voltage; A boost circuit processes the first voltage to generate a second voltage; A step-down circuit processes the second voltage to generate the first DC power supply; and A feedback compensation circuit generates a feedback signal based on the first DC power supply; The step-down circuit adjusts the first DC power supply based on the feedback signal.

4. The power supply of claim 3, wherein the step-down circuit comprises: A first pulse width modulation circuit generates a first switching signal and a second switching signal based on the feedback signal; A first switch receives the first switching signal and is coupled between a first node and a second node; A second switch receives the second switching signal and is coupled between the second node and a ground terminal; A resonant circuit is coupled between the second node and the ground terminal to generate a resonant voltage; as well as A transformer generates the first DC power supply based on the resonant voltage.

5. The power supply of claim 4, wherein the resonant circuit comprises: First inductor; A second inductor; as well as A resonant capacitor; The first inductor, the second inductor, and the resonant capacitor are connected in series between the second node and the ground terminal.

6. The power supply of claim 5, wherein the second inductor is connected in parallel with a primary winding of the transformer.

7. The power supply of claim 6, wherein the first discharge circuit comprises: A discharge switch is coupled between the first output capacitor and the second inductor; as well as A comparison circuit is used to turn on the discharge switch when the first DC power supply is greater than the second DC power supply. When the discharge switch is turned on, the discharge switch, the second inductor, and the resonant capacitor form the first discharge path.

8. The power supply of claim 7, wherein the feedback compensation circuit comprises: A first voltage divider circuit processes the first DC power supply to generate a first voltage divider. A compensation capacitor receives the first divided voltage and is coupled to the comparator circuit; A voltage regulator is coupled between the compensation capacitor and the ground terminal and receives the first voltage divider. A linear optocoupler generates the feedback signal based on the first DC power supply; A start-up resistor is coupled between the first output capacitor and the linear optocoupler; and A feedback capacitor is coupled between the linear optocoupler and the ground terminal.

9. The power supply of claim 8, wherein the AC-DC converter comprises: A bridge rectifier converts the first AC power supply to generate the first voltage; as well as An input capacitor stores the first voltage.

10. The power supply of claim 9, further comprising: A second voltage divider circuit processes the first voltage to generate a second voltage divider. A second pulse width modulation circuit receives the second voltage divider and provides a third switching signal; A power switch receives the third switching signal; A boost inductor is coupled between the second voltage divider circuit and the power switch; An output diode is coupled between the boost inductor and the first node; and A boost capacitor is coupled between the first node and the ground terminal.

11. A control system, comprising: A first power supply, comprising: A first input terminal is used to receive a first AC power source; A first conversion circuit converts the first AC power supply into a first DC power supply. A first output capacitor is used to store the first DC power supply; A first discharge circuit, when the first DC power supply is greater than a second DC power supply, establishes a first discharge path to discharge the first output capacitor; and A first output terminal is used to output the first DC power supply; A second power supply, comprising: A second input terminal is used to receive a second AC power source; A second conversion circuit converts the second AC power supply into the second DC power supply; A second output capacitor is used to store the second DC power supply; A second discharge circuit, when the second DC power supply is greater than the first DC power supply, establishes a second discharge path to discharge the second output capacitor; and A second output terminal, used to output the second DC power supply; and A system load includes: A first interface has a first power receiving end and a first connection end. When the first output end is coupled to the first interface, the first power receiving end receives the first DC power supply, and the first connection end is electrically connected to the first discharge circuit. A second interface has a second power receiving end and a second connection end. The second power receiving end is electrically connected to the first power receiving end, and the second connection end is electrically connected to the first connection end. When the second output end is coupled to the second interface, the second power receiving end receives the second DC power supply, and the second connection end is electrically connected to the second discharge circuit.

12. The control system of claim 11, wherein the first discharge circuit comprises: A discharge switch is coupled to the first output capacitor; An impedance element is coupled between the discharge switch and a ground terminal; as well as A comparison circuit is used to turn on the discharge switch when the first DC power supply is greater than the second DC power supply. When the discharge switch is turned on, the discharge switch and the impedance element form the first discharge path.

13. The control system of claim 12, wherein when the first output terminal is coupled to the first interface, an inverting input terminal of the comparator circuit is electrically connected to the first connection terminal.

14. The control system of claim 11, wherein the first conversion circuit comprises: An AC-DC converter converts the first AC power supply into a first voltage; A boost circuit processes the first voltage to generate a second voltage; A step-down circuit processes the second voltage to generate the first DC power supply; and A feedback compensation circuit generates a feedback signal based on the first DC power supply; The step-down circuit adjusts the first DC power supply based on the feedback signal.

15. The control system of claim 14, wherein the step-down circuit comprises: A first pulse width modulation circuit generates a first switching signal and a second switching signal based on the feedback signal; A first switch receives the first switching signal and is coupled between a first node and a second node; A second switch receives the second switching signal and is coupled between the second node and a ground terminal; A resonant circuit is coupled between the second node and the ground terminal to generate a resonant voltage; as well as A transformer generates the first DC power supply based on the resonant voltage.

16. The control system of claim 15, wherein the resonant circuit comprises: First inductor; A second inductor; and A resonant capacitor; The first inductor, the second inductor, and the resonant capacitor are connected in series between the second node and the ground terminal.

17. The control system of claim 16, wherein the second inductor is connected in parallel with a primary winding of the transformer.

18. The control system of claim 17, wherein the first discharge circuit comprises: A discharge switch is coupled between the first output capacitor and the second inductor; as well as A comparison circuit is used to turn on the discharge switch when the first DC power supply is greater than the second DC power supply. When the discharge switch is turned on, the discharge switch, the second inductor, and the resonant capacitor form the first discharge path.

19. The control system of claim 18, wherein when the first output terminal is coupled to the first interface, an inverting input terminal of the comparator circuit is electrically connected to the first connection terminal.

20. The control system of claim 19, wherein the first power supply further comprises: A voltage divider circuit processes the first DC power supply to generate a divided voltage. A compensation capacitor is coupled between the voltage divider circuit and a non-inverting input terminal of the comparator circuit; A voltage regulator is coupled between the compensation capacitor and the ground terminal and receives the divided voltage. A linear optocoupler generates the feedback signal based on the first DC power supply; A feedback capacitor is coupled between the linear optocoupler and the ground terminal; and A sensing resistor is coupled between the inverting input terminal and the non-inverting input terminal.

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