Power supply device
The power supply device efficiently converts and boosts multiple voltages into a single voltage using a single converter, addressing size and cost issues in existing technologies by employing a self-excited vibration circuit and control units, thereby reducing hardware and preventing magnetic saturation.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- SHINDENGEN ELECTRIC MANUFACTURING CO LTD
- Filing Date
- 2022-09-13
- Publication Date
- 2026-07-30
AI Technical Summary
Existing technologies face challenges in converting multiple power outputs from various environmental power sources into a single power source efficiently, leading to larger size and higher costs due to the need for multiple converters.
A power supply device utilizing a single converter with multiple input terminals, inductors, diodes, transistors, capacitors, and a self-excited vibration circuit to convert and boost multiple voltages into a single voltage, incorporating a startup unit, on-control and off-control units, and an output voltage detection unit to manage transistor switching.
The solution enables efficient conversion and boosting of multiple voltages into a single voltage using a single converter, reducing hardware requirements and costs while preventing magnetic saturation and excessive current flow.
Smart Images
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Abstract
Description
[Technical Field]
[0001] This disclosure relates to a power supply device. [Background technology]
[0002] In recent years, energy harvesting (environmental power generation) has become increasingly common. Energy harvesting is a technology that extracts energy from sources such as sunlight, artificial light, vibrations from machinery, and heat to generate electricity. The challenge lies in converting the multiple power outputs from these various environmental power sources into a single power source.
[0003] Patent Document 1 describes a step-down chopper type DC-DC converter that converts multiple power outputs from multiple DC input power sources into a single power output. [Prior art documents] [Patent Documents]
[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-285005 [Overview of the Initiative] [Problems that the invention aims to solve]
[0005] It is desirable to convert multiple voltages output from multiple power sources into a single voltage using a single converter and then boost it.
[0006] This disclosure aims to convert multiple voltages output from multiple power sources into a single voltage using a single converter and boost it. [Means for solving the problem]
[0007] A power supply device in one aspect of this disclosure is Multiple input terminals, each electrically connected to multiple DC power supplies, Output terminal that outputs a DC output voltage, A plurality of first inductors, each having one end electrically connected to the plurality of input terminals, A plurality of first diodes, each having an anode electrically connected to the other end of the plurality of first inductors and a cathode electrically connected to the first node, A first transistor having its collector or drain electrically connected to the first node, a control signal input to its base or gate, and its emitter or source electrically connected to a reference potential, A second diode, the anode of which is electrically connected to the collector or drain of the first transistor and the cathode of which is electrically connected to the output terminal, A first capacitor, one end of which is electrically connected to the output terminal and the other end of which is electrically connected to a reference potential, A self-excited circuit that performs self-excitement based on the current flowing through the first node and outputs the control signal resulting from the self-excitement to the base or gate of the first transistor, including, It is characterized by the following:
[0008] In the aforementioned power supply device, The aforementioned self-excited vibration circuit is Multiple second capacitors are connected in parallel to each of the multiple first diodes, A second inductor comprising: a first winding having one end electrically connected to the first node and the other end electrically connected to the collector or drain of the first transistor; and a second winding having one end electrically connected to a reference potential and the other end electrically connected to a second node, the other end of which induces a voltage in the opposite direction to the voltage induced in the first winding; A third capacitor, with one end electrically connected to the collector or drain of the first transistor and the other end electrically connected to a reference potential, A startup unit, one end of which is electrically connected to the other end of the first winding and the other end of which is electrically connected to the base or gate of the first transistor, controls the first transistor to turn on by outputting the voltage or current from the other end of the first winding to the base or gate of the first transistor, An on-control unit that is electrically connected at one end to the second node and at the other end to the base or gate of the first transistor, and controls the first transistor to turn on when a voltage induced at the other end of the second winding reaches a predetermined voltage; An off-control unit that is electrically connected at one end to the second node and at the other end to the base or gate of the first transistor, and controls the first transistor to turn off when a predetermined time has elapsed after the voltage induced at the other end of the second winding reaches a predetermined voltage; comprising characterized in that
[0009] In the power supply device, The on-control unit a first resistor having one end electrically connected to the second node; a third diode having an anode electrically connected to the other end of the first resistor and a cathode electrically connected to the base or gate of the first transistor; a fourth capacitor connected in parallel with the third diode; comprising characterized in that
[0010] In the power supply device, The off-control unit a second transistor having a collector or drain electrically connected to the base or gate of the first transistor and an emitter or source electrically connected to a reference potential; a fifth capacitor having one end electrically connected to the base or gate of the second transistor and the other end electrically connected to the reference potential; a second resistor having one end electrically connected to the second node and the other end electrically connected to one end of the fifth capacitor; comprising characterized in that
[0011] In the power supply device, The self-excitation oscillation circuit An output voltage detection unit for detecting the DC output voltage, A regulating charging current supply unit outputs a current to one end of the fifth capacitor based on the voltage detected by the output voltage detection unit, including, It is characterized by the following: [Effects of the Invention]
[0012] According to this disclosure, multiple voltages output from multiple power sources can be converted into a single voltage and boosted using a single converter. [Brief explanation of the drawing]
[0013] [Figure 1] Figure 1 shows the configuration of the power supply unit of the first comparative example. [Figure 2] Figure 2 shows the configuration of the boost chopper in the power supply unit of the first comparative example. [Figure 3] Figure 3 shows the configuration of the power supply unit in the second comparative example. [Figure 4] Figure 4 shows the current waveform of the power supply unit in the second comparative example. [Figure 5] Figure 5 shows the configuration of the power supply unit in the embodiment. [Figure 6] Figure 6 shows the operation sequence of the power supply unit according to the embodiment. [Figure 7] Figure 7 shows the voltage or current waveforms of each part of the power supply unit according to the embodiment. [Figure 8] Figure 8 shows the direction of current in each part of the power supply device according to the embodiment. [Figure 9] Figure 9 shows the direction of current in each part of the power supply device according to the embodiment. [Figure 10] Figure 10 is a diagram showing the direction of current in each part of the power supply device according to the embodiment. [Figure 11] Figure 11 is a diagram showing the direction of current in each part of the power supply device according to the embodiment. [Figure 12] Figure 12 is a diagram showing the direction of current in each part of the power supply device according to the embodiment. [Figure 13] Figure 13 is a diagram showing the direction of current in each part of the power supply device according to the embodiment. [Figure 14] Figure 14 is a diagram showing the direction of current in each part of the power supply device of the embodiment. [Figure 15] Figure 15 is a diagram showing the direction of current in each part of the power supply device according to the embodiment. [Figure 16] Figure 16 shows the current waveforms of each part of the power supply unit according to the embodiment. [Modes for carrying out the invention]
[0014] Embodiments relating to this disclosure will be described in detail below with reference to the attached drawings. However, this embodiment does not limit the disclosure, and in the following embodiments, the same parts are denoted by the same reference numerals to avoid redundant explanations.
[0015] <Embodiment> The embodiments will be described below, but for ease of understanding, comparative examples will be described first.
[0016] (Comparative Example 1) Figure 1 shows the configuration of the power supply unit of the first comparative example. The power supply unit 101 includes boost choppers 102, 103 and 104.
[0017] The first input terminal 102a of the boost chopper 102 is electrically connected to one end (high potential side) of the power supply 2. The second input terminal 102b of the boost chopper 102 is electrically connected to the other end (low potential side) of the power supply 2 and to the reference potential.
[0018] Power supply 2 outputs a voltage Vin1 between the first input terminal 102a and the second input terminal 102b.
[0019] The first output terminal 102c of the boost chopper 102 is electrically connected to one end (high potential side) of the load 5. The second output terminal 102d of the boost chopper 102 is electrically connected to the other end (low potential side) of the load 5.
[0020] The boost chopper 102 outputs a voltage Vout between the first output terminal 102c and the second output terminal 102d.
[0021] The first input terminal 103a of the boost chopper 103 is electrically connected to one end (high potential side) of the power supply 3. The second input terminal 103b of the boost chopper 103 is electrically connected to the other end (low potential side) of the power supply 3 and to the reference potential.
[0022] Power supply 3 outputs a voltage Vin2 between the first input terminal 103a and the second input terminal 103b.
[0023] The first output terminal 103c of the boost chopper 103 is electrically connected to one end (high potential side) of the load 5. The second output terminal 103d of the boost chopper 103 is electrically connected to the other end (low potential side) of the load 5.
[0024] The boost chopper 103 outputs a voltage Vout between the first output terminal 103c and the second output terminal 103d.
[0025] The first input terminal 104a of the boost chopper 104 is electrically connected to one end (high potential side) of the power supply 4. The second input terminal 104b of the boost chopper 104 is electrically connected to the other end (low potential side) of the power supply 4 and to the reference potential.
[0026] Power supply 4 outputs a voltage Vin3 between the first input terminal 104a and the second input terminal 104b.
[0027] The first output terminal 104c of the boost chopper 104 is electrically connected to one end (high potential side) of the load 5. The second output terminal 104d of the boost chopper 104 is electrically connected to the other end (low potential side) of the load 5.
[0028] The boost chopper 104 outputs a voltage Vout between the first output terminal 104c and the second output terminal 104d.
[0029] Figure 2 shows the configuration of the boost chopper in the power supply unit of the first comparative example. Figure 2 shows the configuration of boost chopper 102. The configurations of boost choppers 103 and 104 are the same as those of boost chopper 102, so their illustration and description are omitted.
[0030] The boost chopper 102 includes an inductor L1, a transistor Q1, a diode D1, a capacitor C1, and a control circuit 105.
[0031] Transistor Q1 corresponds to an example of the “first transistor” in this disclosure. Diode D1 corresponds to an example of the “second diode” in this disclosure. Capacitor C1 corresponds to an example of the “first capacitor” in this disclosure.
[0032] One end of inductor L1 is electrically connected to the first input terminal 102a. The other end of inductor L1 is electrically connected to the collector of transistor Q1 and the anode of diode D1.
[0033] The emitter of transistor Q1 is electrically connected to the second input terminal 102b and the second output terminal 102d. A switching control signal S1 is input to the base of transistor Q1 from the control circuit 105.
[0034] In this disclosure, each transistor is assumed to be a bipolar transistor, but is not limited to this. Each transistor may also be an FET. When a transistor is an FET, the source of the FET corresponds to the emitter of the bipolar transistor, the gate of the FET corresponds to the base of the bipolar transistor, and the drain of the FET corresponds to the collector of the bipolar transistor.
[0035] The cathode of diode D1 is electrically connected to one end of capacitor C1 and the first output terminal 102c.
[0036] The other end of capacitor C1 is electrically connected to the second input terminal 102b and the second output terminal 102d. The voltage across capacitor C1 is the voltage Vout.
[0037] The control circuit 105 includes an output voltage detection unit 105a, a control unit 105b, and a drive unit 105c.
[0038] The output voltage detection unit 105a detects the voltage Vout and outputs the detection signal S11 to the control unit 105b.
[0039] Based on the detection signal S11, the control unit 105b generates a switching control signal S12 so that the voltage Vout becomes the target voltage, and outputs it to the drive unit 105c.
[0040] The drive unit 105c outputs a switching control signal S1, which is obtained by converting the voltage level of the switching control signal S12, to the base of the transistor Q1.
[0041] When transistor Q1 is ON, inductor L1 stores current (electromagnetic energy). When transistor Q1 is OFF, inductor L1 releases current. The voltage Vout, which is the sum of voltage Vin1 and the voltage across inductor L1, is applied to capacitor C1.
[0042] The power supply unit 101 of the first comparative example requires the same number of boost choppers 102, 103, and 104 as the number of power supplies (3 in this example), which results in a larger size and higher cost.
[0043] (Comparative Example 2) For components of the second comparative example that are the same as those of the first comparative example, the same reference numerals are used and their descriptions are omitted.
[0044] Figure 3 shows the configuration of the power supply unit in the second comparative example.
[0045] Compared to the boost chopper 102 (see Figure 2), the power supply unit 111 further includes inductors L2 and L3, and diodes D2, D3 and D4.
[0046] Inductors L1, L2, and L3 correspond to examples of the “multiple first inductors” of this disclosure. Diodes D2, D3, and D4 correspond to examples of the “multiple first diodes” of this disclosure.
[0047] The first input terminal 111a of the power supply unit 111 is electrically connected to one end (high potential side) of power supply 2. The second input terminal 111b of the power supply unit 111 is electrically connected to one end (high potential side) of power supply 3. The third input terminal 111c of the power supply unit 111 is electrically connected to one end (high potential side) of power supply 4. The fourth input terminal 111d of the power supply unit 111 is electrically connected to the other ends (low potential side) of power supplies 2, 3, and 4, as well as to the reference potential.
[0048] Power supply 2 outputs voltage Vin1 between the first input terminal 111a and the fourth input terminal 111d. Power supply 3 outputs voltage Vin2 between the second input terminal 111b and the fourth input terminal 111d. Power supply 4 outputs voltage Vin3 between the third input terminal 111c and the fourth input terminal 111d.
[0049] The first output terminal 111e of the power supply unit 111 is electrically connected to one end (high potential side) of the load 5. The second output terminal 111f of the power supply unit 111 is electrically connected to the other end (low potential side) of the load 5.
[0050] The power supply unit 111 outputs a voltage Vout between the first output terminal 111e and the second output terminal 111f.
[0051] One end of inductor L1 is electrically connected to the first input terminal 111a. The other end of inductor L1 is electrically connected to the anode of diode D2. The current flowing from one end to the other of inductor L1 is called current IL1.
[0052] The cathode of diode D2 is electrically connected to node N1. Diode D2 prevents reverse current from flowing through inductor L1.
[0053] Node N1 corresponds to an example of the “first node” in this disclosure.
[0054] One end of inductor L2 is electrically connected to the second input terminal 111b. The other end of inductor L2 is electrically connected to the anode of diode D3. The current flowing from one end to the other of inductor L2 is called current IL2.
[0055] The cathode of diode D3 is electrically connected to node N1. Diode D3 prevents reverse current from flowing through inductor L2.
[0056] One end of inductor L3 is electrically connected to the third input terminal 111c. The other end of inductor L3 is electrically connected to the anode of diode D4. The current flowing from one end to the other of inductor L3 is called current IL3.
[0057] The cathode of diode D4 is electrically connected to node N1. Diode D4 prevents reverse current from flowing through inductor L3.
[0058] The sum of currents IL1, IL2, and IL3 is called current IL4.
[0059] The anode of diode D1 and the collector of transistor Q1 are electrically connected to node N1.
[0060] When the transistor Q1 is in the on state, the inductors L1, L2, and L3 accumulate current (electromagnetic energy). When the transistor Q1 is in the off state, the inductors L1, L2, and L3 release current. The voltage Vout, which is the maximum voltage among the voltages obtained by adding the voltage Vin1 and the voltage of the inductor L1, the voltage obtained by adding the voltage Vin2 and the voltage of the inductor L2, and the voltage obtained by adding the voltage Vin3 and the voltage of the inductor L3, is applied to the capacitor C1.
[0061] FIG. 4 is a diagram showing the current waveforms of the power supply device of the second comparative example. Waveform 201 is the waveform of the current IL1. Waveform 202 is the waveform of the current IL2. Waveform 203 is the waveform of the current IL3.
[0062] Timing t 111 is the timing when the transistor Q1 turns on. Timing t 112 is the timing when the transistor Q1 turns off. Timing t 113 is the timing when the transistor Q1 turns on. Timing t 114 is the timing when the transistor Q1 turns off.
[0063] Timing t 111 From timing t 112 to timing t
[0064] During this period, since the inductors L1, L2, and L3 accumulate current, the currents IL1, IL2, and IL3 increase. 112 From timing t 113 to timing t
[0065] During this period, since the inductors L1, L2, and L3 release current, the currents IL1, IL2, and IL3 decrease. 113 From timing t 114 to timing t
[0066] Voltages Vin1, Vin2, and Vin3 are not necessarily the same. Also, inductors L1, L2, and L3 may have individual variations. This means that currents IL1, IL2, and IL3 may be uneven. Therefore, the timing of transistor Q1 changing from off to on (timing t) 113 (See reference) In this example, the current accumulates without any of the currents IL1, IL2, and IL3 (in this example, current IL1 (waveform 201)) becoming zero. As a result, magnetic saturation occurs in any of the inductors L1, L2, and L3 (in this example, inductor L1), or an excessive current flows.
[0067] (Embodiment) [composition] For components of the embodiment that are the same as those of the first comparative example or the second comparative example, the same reference numerals are used and their descriptions are omitted.
[0068] Figure 5 shows the configuration of the power supply unit in the embodiment.
[0069] Power supply unit 1 further includes a self-excited vibration circuit 11 compared to power supply unit 111 (see Figure 3). The self-excited vibration circuit 11 performs self-excitation based on the current flowing through node N1, i.e., current IL4, and outputs a control signal resulting from the self-excitation to the base of transistor Q1.
[0070] The self-excited vibration circuit 11 includes capacitors C11, C12, C13, and C14, an inductor L11, a starting unit 21, an ON control unit 22, an OFF control unit 23, an output voltage detection unit 24, and an adjustable charging current output unit 25.
[0071] Capacitors C11, C12, and C13 correspond to examples of the “multiple second capacitors” in this disclosure. Capacitor C14 corresponds to an example of the “third capacitor” in this disclosure. Inductor L11 corresponds to an example of the “second inductor” in this disclosure.
[0072] In this embodiment, the case where there are three power supplies is described, but the disclosure is not limited to this. The number of power supplies may be two or fewer, or four or more. Depending on the number of power supplies, the number of multiple first inductors, multiple first diodes, and multiple second capacitors may be changed.
[0073] The first input terminal 1a of power supply unit 1 is electrically connected to one end (high potential side) of power supply unit 2. The second input terminal 1b of power supply unit 1 is electrically connected to one end (high potential side) of power supply unit 3. The third input terminal 1c of power supply unit 1 is electrically connected to one end (high potential side) of power supply unit 4. The fourth input terminal 1d of power supply unit 1 is electrically connected to the other ends (low potential sides) of power supplies 2, 3, and 4, as well as to the reference potential.
[0074] The first output terminal 1e of power supply unit 1 is electrically connected to one end (high potential side) of load 5. The second output terminal 1f of power supply unit 1 is electrically connected to the other end (low potential side) of load 5.
[0075] Power supply unit 1 outputs a voltage Vout between the first output terminal 1e and the second output terminal 1f.
[0076] One end of capacitor C11 is electrically connected to the anode of diode D2. The other end of capacitor C11 is electrically connected to the cathode of diode D2. Capacitor C11 stores the current flowing in the reverse direction of diode D2 (from cathode to anode).
[0077] One end of capacitor C12 is electrically connected to the anode of diode D3. The other end of capacitor C12 is electrically connected to the cathode of diode D3. Capacitor C12 stores the current flowing in the reverse direction of diode D3 (from cathode to anode).
[0078] One end of capacitor C13 is electrically connected to the anode of diode D4. The other end of capacitor C13 is electrically connected to the cathode of diode D4. Capacitor C13 stores the current flowing in the reverse direction of diode D4 (from cathode to anode).
[0079] The inductor L11 includes a first winding L11a, a second winding L11b, and a core L11c. The first winding L11a and the second winding L11b are wound around the core L11c. The second winding L11b is wound around the core L11c in a direction that induces a voltage in the opposite direction to the voltage induced in the first winding L11a.
[0080] One end of the first winding L11a is electrically connected to node N1. The other end of the first winding L11a is electrically connected to one end of the starter unit 21, the collector of transistor Q1, and the anode of diode D1.
[0081] The other end of the startup unit 21 is electrically connected to the base of transistor Q1.
[0082] The startup unit 21 controls transistor Q1 to turn on when the power supply unit 1 is started by outputting the voltage or current from the other end of the first winding L11a to the base of transistor Q1.
[0083] The startup unit 21 includes a resistor R21. One end of resistor R21 is electrically connected to the other end of the first winding L11a. The other end of resistor R21 is electrically connected to the base of transistor Q1.
[0084] One end of the second winding L11b is electrically connected to the fourth input terminal 1d and the second output terminal 1f. The other end of the second winding L11b is electrically connected to node N2.
[0085] Node N2 corresponds to an example of the “second node” in this disclosure.
[0086] One end of the ON control unit 22 is electrically connected to node N2. The other end of the ON control unit 22 is electrically connected to the base of transistor Q1.
[0087] The ON control unit 22 controls transistor Q1 to turn ON when the voltage induced at the other end of the second winding L11b reaches a predetermined voltage.
[0088] The ON control unit 22 includes a resistor R31, a diode D31, and a capacitor C31.
[0089] Resistor R31 corresponds to an example of the “first resistor” in this disclosure. Diode D31 corresponds to an example of the “third diode” in this disclosure. Capacitor C31 corresponds to an example of the “fourth capacitor” in this disclosure.
[0090] One end of resistor R31 is electrically connected to node N2. The other end of resistor R31 is electrically connected to the anode of diode D31 and one end of capacitor C31.
[0091] The cathode of diode D31 and the other end of capacitor C31 are electrically connected to the base of transistor Q1. Capacitor C31 stores the current flowing in the reverse direction of diode D31 (from cathode to anode).
[0092] The off-control unit 23 controls transistor Q1 to turn off when a predetermined time has elapsed after the voltage induced at the other end of the second winding L11b reaches a predetermined voltage.
[0093] The off-control unit 23 includes a transistor Q41, a capacitor C41, and a resistor R41.
[0094] Transistor Q41 corresponds to an example of the “second transistor” in this disclosure. Capacitor C41 corresponds to an example of the “fifth capacitor” in this disclosure. Resistor R41 corresponds to an example of the “second resistor” in this disclosure.
[0095] The collector of transistor Q41 is electrically connected to the base of transistor Q1. The emitter of transistor Q41 is electrically connected to the fourth input terminal 1d and the second output terminal 1f.
[0096] One end of capacitor C41 is electrically connected to the base of transistor Q41. The other end of capacitor C41 is electrically connected to the fourth input terminal 1d and the second output terminal 1f.
[0097] One end of resistor R41 is electrically connected to node N2. The other end of resistor R41 is electrically connected to one end of capacitor C41.
[0098] One end of capacitor C14 is electrically connected to the collector of transistor Q1. The other end of capacitor C14 is electrically connected to the fourth input terminal 1d and the second output terminal 1f.
[0099] The output voltage detection unit 24 detects the voltage Vout and outputs the detection signal to the regulated charging current output unit 25. The regulated charging current output unit 25 outputs a current to one end of the capacitor C41 based on the detection signal input from the output voltage detection unit 24. The regulated charging current output unit 25 can adjust the voltage rise of the capacitor C41.
[0100] [Operation] Figures 6 to 15 illustrate the operation of the power supply unit in the embodiment.
[0101] Figure 6 shows the operation sequence of power supply unit 1.
[0102] Figure 7 shows the voltage and current waveforms of various parts of the power supply unit 1. Waveform 301 shows the collector-emitter voltage of transistor Q1. Waveform 302 shows the current IL4. Waveform 303 shows the voltage across the second winding L11b of inductor L11. Waveform 304 shows the voltage across capacitor C41.
[0103] Figures 8 through 15 show the direction of current in each part of the power supply unit 1.
[0104] Referring to Figure 6, in step S100, current is supplied from resistor R21 to the gate of transistor Q1. Referring to Figure 8, since the voltage at node N1 is high, current is supplied from node N1 to the base of transistor Q1 via the first winding L11a and resistor R21, as indicated by arrow 401.
[0105] Power supply unit 1 performs step S102 after step S100.
[0106] Referring to Figure 6, in step S102, transistor Q1 turns ON. Referring to Figure 7, as shown by waveform 301, after timing t1 (step S100), transistor Q1 turns ON, so the collector-emitter voltage becomes low level. Referring to Figure 9, as transistor Q1 turns ON, the collector-emitter of transistor Q1 becomes conductive, as shown by arrow 402.
[0107] Power supply unit 1 performs steps S104 and S106 after step S102.
[0108] Referring to Figure 6, in step S104, the collector-emitter of transistor Q1 is conducting, so the first winding L11a of inductor L11 accumulates current IL4. Referring to Figure 7, as shown in waveform 302, the first winding L11a of inductor L11 accumulates current IL4 from timing t1 onward.
[0109] Referring to Figure 6, in step S106, capacitor C41 begins to charge. Referring to Figure 7, as shown by waveform 304, after timing t1, capacitor C41 begins to charge and the voltage across capacitor C41 rises. In this example, current is supplied to capacitor C41 through two paths. Referring to Figure 10, a positive voltage is induced at the other end of the second winding L11b, so as shown by arrow 403, current is supplied from the other end of the second winding L11b through resistor R41 to one end of capacitor C41. In addition, the output voltage detection unit 24 outputs a detection signal to the regulated charging current output unit 25, and the regulated charging current output unit 25 outputs a current corresponding to the detection signal to one end of capacitor C41, as shown by arrow 404.
[0110] Power supply unit 1 performs step S108 after step S106.
[0111] Referring to Figure 6, in step S108, when the voltage across capacitor C41 reaches the base threshold voltage of transistor Q41, transistor Q41 turns on, and the base of transistor Q1 goes low, so transistor Q1 turns off. Referring to Figure 7, as shown by waveform 301, at timing t2 (step S108), transistor Q1 turns off, so the collector-emitter voltage becomes voltage Vout.
[0112] Power supply unit 1 performs steps S110, S112, and S114 after step S108.
[0113] Referring to Figure 6, in step S110, the first winding L11a of inductor L11 discharges current IL4. Referring to Figure 7, as shown by waveform 302, the first winding L11a of inductor L11 discharges current IL4 from timing t2 onward. Referring to Figure 11, as shown by arrow 405, current IL4 flows from the first winding L11a of inductor L11 through diode D1 to capacitor C1.
[0114] Power supply unit 1 performs step S118 after step S110. Step S118 will be explained later.
[0115] Referring to Figure 6, in step S112, the first winding L11a of inductor L11 boosts the voltage at node N1 and outputs voltage Vout. Referring to Figure 7, as shown in waveform 301, at timing t2 (step S112), the first winding L11a of inductor L11 boosts the voltage at node N1 and outputs voltage Vout, so the collector-emitter voltage of transistor Q1 becomes voltage Vout.
[0116] Power supply unit 1 performs step S116 after step S112. Step S116 will be explained later.
[0117] Referring to Figure 6, in step S114, capacitor C41 begins to discharge. Referring to Figure 7, as shown by waveform 304, after timing t2, capacitor C41 begins to discharge and the voltage across capacitor C41 decreases. Referring to Figure 12, a reverse voltage is induced at the other end of the second winding L11b, so as shown by arrow 406, current flows from one end of capacitor C41 through resistor R41 to the other end of the second winding L11b.
[0118] Referring to Figure 6, in step S116, capacitor C14 is charged to voltage Vout. Referring to Figure 7, as shown by waveform 301, from timing t2 onward, the collector-emitter voltage of transistor Q1 is voltage Vout, so capacitor C14 is charged to voltage Vout. Referring to Figure 13, as shown by arrow 407, current flows from the other end of the first winding L11a of inductor L11 to one end of capacitor C14, and capacitor C14 is charged to voltage Vout.
[0119] Referring to Figure 6, at step S118, the current IL4 in the first winding L11a of inductor L11 becomes zero. Referring to Figure 7, as shown in waveform 302, at timing t3 (step S118), the current IL4 in the first winding L11a of inductor L11 becomes zero.
[0120] Power supply unit 1 performs step S120 after step S118.
[0121] Referring to Figure 6, in step S120, the voltage across capacitor C14 energizes the first winding L11a of inductor L11 with a reverse current IL4. Referring to Figure 7, as shown by waveform 302, a reverse current IL4 flows through the first winding L11a of inductor L11 from timing t3 onward. Referring to Figure 14, as indicated by arrow 408, the voltage across capacitor C14 energizes the first winding L11a of inductor L11 with a reverse current IL4. The reverse current IL4 is distributed and stored in capacitors C11, C12, and C13.
[0122] Power supply unit 1 performs step S122 after step S120.
[0123] Referring to Figure 6, in step S122, the voltage across capacitor C14 drops to voltage Vin. Referring to Figure 7, as the voltage across capacitor C14 drops to voltage Vin, the collector-emitter voltage of transistor Q1 also drops to voltage Vin, as shown in waveform 301.
[0124] Power supply unit 1 performs step S124 after step S122.
[0125] Referring to Figure 6, in step S124, the voltage across capacitor C14 drops below the voltage Vin. Referring to Figure 7, since the voltage across capacitor C14 drops below the voltage Vin, the collector-emitter voltage of transistor Q1 drops below the voltage Vin, as shown in waveform 301.
[0126] Power supply unit 1 performs step S126 after step S124.
[0127] Referring to Figure 6, in step S126, the second winding L11b of inductor L11 generates a voltage. Referring to Figure 7, as shown by waveform 303, the second winding L11b of inductor L11 generates a voltage. Referring to Figure 15, as shown by arrow 409, current flows from the other end of the second winding L11b of inductor L11 through resistor R31 and diode D31 to the base of transistor Q1.
[0128] Power supply unit 1 performs step S102 after step S126. Referring to Figure 7, at timing t4, transistor Q1 turns on and the collector-emitter voltage becomes low.
[0129] (Effects compared to the first comparative example) The power supply unit 1 of this embodiment (see Figure 5) can reduce the amount of hardware compared to the power supply unit 101 of the first comparative example (see Figures 1 and 2), thus preventing it from becoming larger and reducing costs.
[0130] (Effects compared to the second comparative example) As explained earlier, in the power supply unit 111 of the second comparative example (see Figure 3), the current accumulates without any of the currents IL1, IL2, and IL3 (in the example in Figure 4, current IL1 (waveform 201)) becoming zero. As a result, magnetic saturation occurs in any of the inductors L1, L2, and L3 (in the example in Figure 4, inductor L1), or excessive current flows.
[0131] On the other hand, in the power supply device 1 of the embodiment, at timing t4 (see Figure 7), when the current IL4 flowing through the first winding L11a of the inductor L11 is zero or less, that is, when all currents IL1, IL2, and IL3 are zero or less, the transistor Q1 changes from off to on.
[0132] Figure 16 shows the currents in each part of the power supply unit of the embodiment. Waveform 501 is the waveform of current IL1. Waveform 502 is the waveform of current IL2. Waveform 503 is the waveform of current IL3. Waveform 504 is the waveform of current IL4.
[0133] timing t 11 This is the timing at which transistor Q1 turns on. 12 This is the timing at which transistor Q1 turns off. 13 This is the timing when the current IL4 becomes zero. 14 This is the timing at which transistor Q1 turns on. 15 This is the timing when transistor Q1 turns off.
[0134] timing t 11 from timing t 12 During this period, inductors L1, L2, L3, and L11 accumulate current, so currents IL1, IL2, IL3, and IL4 increase.
[0135] timing t 12 from timing t 13 During this period, inductors L1, L2, L3, and L11 release current, so currents IL1, IL2, IL3, and IL4 decrease.
[0136] timing t 13 Therefore, current IL4 becomes zero, meaning that currents IL1, IL2, and IL3 all become zero.
[0137] timing t 14 from timing t 15 During this period, inductors L1, L2, L3, and L11 accumulate current, so currents IL1, IL2, IL3, and IL4 increase.
[0138] As mentioned above, voltages Vin1, Vin2, and Vin3 are not necessarily the same. Also, there may be individual differences in inductors L1, L2, and L3. In other words, there may be bias in currents IL1, IL2, and IL3. However, in power supply unit 1, current IL4 becomes zero, that is, all currents IL1, IL2, and IL3 become zero (timing t 13 (See reference), then (timing t) 14 (Reference) Transistor Q1 turns on.
[0139] Therefore, in power supply unit 1, currents IL1, IL2, and IL3 do not accumulate. As a result, power supply unit 1 can suppress magnetic saturation in inductors L1, L2, and L3, and can suppress the flow of excessive current.
[0140] While embodiments of the present disclosure have been described above, the present disclosure is not limited by the content of these embodiments. Furthermore, the aforementioned components include those that are readily conceivable to those skilled in the art, those that are substantially identical, and those that fall within the so-called equivalent range. Moreover, the aforementioned components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the embodiments described above. [Explanation of Symbols]
[0141] 1, 101 power supply 2, 3, 4 power supply 5 load 11 Self-oscillating circuit 21 Starting part 22 ON control unit 23 Off-control unit 24 Output voltage detection unit 25 Adjusted charging current output section 102, 103, 104 Boost Chopper 105 Control circuit L1, L2, L3, L11 Inductors D1, D2, D3, D4, D31 diodes C1, C11, C12, C13, C14, C31, C41 Capacitors R21, R31, R41 resistors Q1, Q41 Transistors
Claims
1. Multiple input terminals, each electrically connected to multiple DC power supplies, Output terminal that outputs a DC output voltage, A plurality of first inductors, each having one end electrically connected to the plurality of input terminals, A plurality of first diodes, each having an anode electrically connected to the other end of the plurality of first inductors and a cathode electrically connected to the first node, A first transistor having its collector or drain electrically connected to the first node, a control signal input to its base or gate, and its emitter or source electrically connected to a reference potential, A second diode, the anode of which is electrically connected to the collector or drain of the first transistor and the cathode of which is electrically connected to the output terminal, A first capacitor, one end of which is electrically connected to the output terminal and the other end of which is electrically connected to a reference potential, A self-excited vibration circuit that performs self-excitement based on the current flowing through the first node and outputs the control signal resulting from the self-excitement to the base or gate of the first transistor, including, A power supply device characterized by the following features.
2. The aforementioned self-excited vibration circuit is Multiple second capacitors are connected in parallel to each of the multiple first diodes, A second inductor comprising: a first winding having one end electrically connected to the first node and the other end electrically connected to the collector or drain of the first transistor; and a second winding having one end electrically connected to a reference potential and the other end electrically connected to a second node, the other end of which induces a voltage in the opposite direction to the voltage induced in the first winding; A third capacitor, one end of which is electrically connected to the collector or drain of the first transistor and the other end of which is electrically connected to a reference potential, A startup unit, one end of which is electrically connected to the other end of the first winding and the other end of which is electrically connected to the base or gate of the first transistor, controls the first transistor to turn on by outputting the voltage or current from the other end of the first winding to the base or gate of the first transistor, An ON control unit, which controls the first transistor to turn ON when the voltage induced at the other end of the second winding reaches a predetermined voltage, is electrically connected to the second node at one end and to the base or gate of the first transistor at the other end. An off-control unit is provided, which has one end electrically connected to the second node and the other end electrically connected to the base or gate of the first transistor, and controls the first transistor to turn off when a predetermined time has elapsed after the voltage induced at the other end of the second winding reaches a predetermined voltage. including, The power supply device according to claim 1, characterized in that
3. The ON control unit, A first resistor, with one end electrically connected to the second node, A third diode, the anode of which is electrically connected to the other end of the first resistor and the cathode of which is electrically connected to the base or gate of the first transistor, A fourth capacitor is connected in parallel to the third diode, including, The power supply device according to claim 2, characterized in that...
4. The aforementioned OFF control unit, A second transistor, the collector or drain of which is electrically connected to the base or gate of the first transistor, and the emitter or source of which is electrically connected to a reference potential, A fifth capacitor, one end of which is electrically connected to the base or gate of the second transistor and the other end of which is electrically connected to a reference potential, A second resistor, with one end electrically connected to the second node and the other end electrically connected to one end of the fifth capacitor, including, The power supply device according to claim 2, characterized in that...
5. The aforementioned self-excited vibration circuit is An output voltage detection unit for detecting the DC output voltage, A regulating charging current supply unit outputs a current to one end of the fifth capacitor based on the voltage detected by the output voltage detection unit, including, The power supply device according to claim 4, characterized in that