CN112134447B - Switching power supply device - Google Patents
Switching power supply device Download PDFInfo
- Publication number
- CN112134447B CN112134447B CN202010572554.4A CN202010572554A CN112134447B CN 112134447 B CN112134447 B CN 112134447B CN 202010572554 A CN202010572554 A CN 202010572554A CN 112134447 B CN112134447 B CN 112134447B
- Authority
- CN
- China
- Prior art keywords
- converter
- signal
- circuit
- output
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33507—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
- H02M1/322—Means for rapidly discharging a capacitor of the converter for protecting electrical components or for preventing electrical shock
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Abstract
Provided is a switching power supply device which suppresses overvoltage generation at the time of restarting a converter without providing a dedicated discharge circuit. A switching power supply device (100) is provided with a 1 st converter (101), a 2 nd converter (102), a standby control circuit (8), and a control unit (9). The control unit outputs a 2 nd signal (S2) for driving the 2 nd converter based on a 1 st signal (S1) from the outside, and when the output voltage of the 1 st converter disappears or drops, the control unit outputs a 3 rd signal (S3) for driving the standby control circuit. Even if the 1 st signal is input to restart the 2 nd converter during a predetermined period of time from the moment when the 1 st signal input is lost, the 2 nd signal output is inhibited, and the standby control circuit is in an operating state by the 3 rd signal output. Therefore, before a certain time elapses, the charge of the capacitor included in the rectifier circuit (22) is discharged through the backup control circuit.
Description
Technical Field
The present invention relates to a switching power supply device having a DC-DC converter that steps down or steps up a direct-current voltage.
Background
For example, an electric vehicle or a hybrid vehicle is equipped with a high-voltage battery for driving a travel motor, and a power supply device for stepping down the voltage of the battery and supplying the battery to each part. As this power supply device, a switching power supply device having a DC-DC converter that switches a DC voltage to convert it into an ac voltage, and rectifies the ac voltage to convert it into a DC voltage of a predetermined voltage value is generally used. For example, patent document 1 and patent document 2 describe such a switching power supply device.
The switching power supply device of patent document 1 has a protection function of holding operation stop when an output voltage is abnormal and a reset function of releasing operation stop holding. When a predetermined time has elapsed after the abnormal-time protection function is activated, a reset signal is output from a reset signal generator. When the switch controlled by the reset signal is turned on, the capacitor as a power source of the control IC for controlling the DC-DC converter is discharged, and the power source voltage of the control IC is lowered, so that the operation stop is released.
In the switching power supply device of patent document 2, after the switching operation is forcibly stopped by the latch signal output at the time of abnormality detection, when the control circuit of the switching element is to be restarted, the charge of the capacitor that supplies power to the control circuit is discharged in advance via the discharge circuit, thereby shortening the restarting time.
The discharge circuits of the capacitors in patent documents 1 and 2 are dedicated circuits provided only for discharging the charges of the capacitors. In addition, in the switching power supply device, as described in detail later, when the time until the DC-DC converter is restarted is short, an overvoltage may be generated in the output of the converter due to the charge of the output capacitor provided on the secondary side of the transformer, but countermeasures thereof are not mentioned in patent documents 1 and 2.
Patent document 1: japanese patent application laid-open No. 2018-174633
Patent document 2: japanese patent laid-open publication No. 2014-64376
Disclosure of Invention
The invention provides a switching power supply device capable of suppressing overvoltage generated when a converter is restarted without providing a special discharge circuit.
The switching power supply device of the present invention includes: an input terminal to which a direct-current voltage is input; a 1 st converter for converting a direct-current voltage inputted to the input terminal into a direct-current voltage having a predetermined voltage value; a 2 nd converter for converting the direct-current voltage inputted to the input terminal into a direct-current voltage having a voltage value different from a predetermined voltage value; a 1 st output terminal outputting the direct current voltage converted by the 1 st converter; a 2 nd output terminal outputting the direct current voltage converted by the 2 nd converter; a control unit that operates with the output voltage of the 1 st converter as a power source, and drives the 2 nd converter in accordance with a 1 st signal supplied from the outside; and a standby control circuit that supplies the output voltage of the 2 nd converter to the control unit as a standby of the power supply of the control unit when the output voltage of the 1 st converter disappears or drops. The 2 nd converter includes: a switching circuit that switches a direct-current voltage input to an input terminal; and a rectifying circuit rectifying the voltage switched by the switching circuit. The switching circuit operates according to the 2 nd signal outputted by the control unit based on the 1 st signal, and the standby control circuit operates according to the 3 rd signal outputted by the control unit when the output voltage of the 1 st converter disappears or drops. During a certain period of time from the moment when the input of the 1 st signal is lost, even if the 1 st signal is input again, the control unit prohibits the output of the 2 nd signal, and the 3 rd signal is output to put the standby control circuit into an operation state. Before a certain time elapses, the charge of the capacitor included in the rectifier circuit is discharged through the backup control circuit.
In this way, even if the time from the stop of the 1 st signal to the re-input is short, the 2 nd converter is not restarted during a certain time period in which the 2 nd signal is not output, and the charge of the capacitor is discharged by the standby control circuit during this time period, so that the 2 nd converter is not over-voltage at the time of restarting. In addition, since the charge of the capacitor is discharged by the existing standby control circuit, a dedicated discharge circuit is not required, and an increase in the number of components can be suppressed, thereby realizing a low-cost switching power supply device.
In the present invention, when the 1 st signal is input at a time point when the predetermined time period has elapsed, the control unit may output the 2 nd signal and stop the output of the 3 rd signal.
In the present invention, the switching power supply device may further include: a driving circuit that drives the switching circuit according to a 2 nd signal from the control unit; and a feedback circuit that performs feedback control for the driving circuit according to the output voltage of the 2 nd converter. In this case, during the predetermined period, the output of the 2 nd signal is inhibited, the drive circuit and the switching circuit are in the non-operating state, and the 2 nd converter stops operating, and in this state, the charge of the capacitor is discharged via the standby control circuit.
In the present invention, the standby control circuit may include: a 1 st switching element forming a supply path for supplying the output voltage of the 2 nd converter to the control section; and a 2 nd switching element which is turned on in accordance with a 3 rd signal from the control section, thereby turning on the 1 st switching element. In this case, a discharge path of the capacitor is formed by the 1 st switching element and the 2 nd switching element.
The 1 st switching element may be a 1 st transistor provided between the 2 nd output terminal and the control unit, the 2 nd switching element may be a 2 nd transistor provided between the base of the 1 st transistor and the ground terminal, and the discharge path of the capacitor may be a discharge path from the emitter of the 1 st transistor to the ground terminal via the collector and the emitter of the 2 nd transistor.
According to the switching power supply device of the present invention, it is possible to suppress generation of an overvoltage at the time of restarting the converter without providing a dedicated discharge circuit.
Drawings
Fig. 1 is a block diagram showing a switching power supply device of the present invention.
Fig. 2 is a circuit diagram of a main portion of fig. 1.
Fig. 3 is a diagram illustrating a discharge path in the circuit of fig. 2.
Fig. 4 is a timing chart for explaining the operation of the circuit of fig. 2.
Fig. 5 is a circuit diagram for explaining a conventional problem.
Fig. 6 is a timing chart for explaining a conventional problem.
Description of the reference numerals
8: a standby control circuit; 9: a control unit; 20: a switching circuit; 22: a rectifying circuit; 27: a PWM circuit (driving circuit); 28: a feedback circuit; 100: a switching power supply device; 101: a 1 st converter; 102: a 2 nd converter; t1 and T2: an input terminal; t3, T4: an output terminal (1 st output terminal); t5, T6: an output terminal (2 nd output terminal); q1: a 1 st transistor (1 st switching element); q2: a 2 nd transistor (2 nd switching element); c1: a capacitor; s1: outputting a request signal (1 st signal); s2: outputting a permission signal (signal 2); s3: standby command signal (3 rd signal).
Detailed Description
Embodiments of the present invention will be described with reference to the accompanying drawings. Hereinafter, a switching power supply device mounted in a vehicle such as a four-wheel car will be exemplified.
In fig. 1, a switching power supply device 100 includes input terminals T1, T2, output terminals T3, T4, output terminals T5, T6, a 1 st converter 101, and a 2 nd converter 102.
The 1 st converter 101 is a DC-DC converter on the main side, converts the DC voltage Vi input to the input terminals T1 and T2 into a DC voltage V1 having a predetermined voltage value, and outputs the DC voltage V1 to the output terminals T3 and T4. The 2 nd converter 102 is a DC-DC converter on the secondary side, converts the DC voltage Vi input to the input terminals T1 and T2 into a DC voltage V2 having a voltage value different from the above-described predetermined voltage value, and outputs the DC voltage V2 to the output terminals T5 and T6. The output terminals T3 and T4 correspond to the "1 st output terminal" in the present invention, and the output terminals T5 and T6 correspond to the "2 nd output terminal" in the present invention.
As an example, the input voltage Vi of the input terminals T1 and T2 is 200V, the output voltage V1 of the output terminals T3 and T4 is 12V, and the output voltage V2 of the output terminals T5 and T6 is 10V. That is, in the case of this example, the 1 st converter 101 and the 2 nd converter 102 are both buck-type DC-DC converters that convert a high voltage to a low voltage.
The input terminal T1 is connected to the positive electrode of a battery (not shown) that supplies the dc voltage Vi, and the input terminal T2 is connected to the negative electrode of the battery. The output terminals T3 and T4 are connected to a load that operates with the output voltage V1 as a power source, a battery that is charged with the output voltage V1, and the like (not shown). The output terminals T5 and T6 are connected to a control circuit or the like (not shown) that operates with the output voltage V2 as a power source. The output terminal T4 and the output terminal T6 among the terminals T1 to T6 are electrically connected to each other outside the switching power supply device 100, and are grounded to a common ground terminal (not shown).
The switching power supply device 100 further includes a voltage detection circuit 6, an internal power supply circuit 7, a standby control circuit 8, a control unit 9, and diodes D1 to D3.
The voltage detection circuit 6 is provided between the output terminal T3 and the control unit 9, and detects the output voltage V1 of the 1 st converter 101. The internal power supply circuit 7 is provided between the standby control circuit 8 and the control unit 9, and normally supplies a power supply voltage to the control unit 9 based on the output voltage V1. The standby control circuit 8 is provided between the output terminal T5 and the internal power supply circuit 7, and supplies the output voltage V2 of the 2 nd converter 102 to the internal power supply circuit 7 as a standby power supply of the control unit 9 when the output voltage V1 of the 1 st converter 101 disappears due to disconnection or failure or falls below a threshold value (at the time of abnormality).
The diode D1 is provided between the output terminal T3 and the internal power supply circuit 7, and forms a supply path for supplying the output voltage V1 of the 1 st converter 101 to the internal power supply circuit 7 in a normal state. The diode D2 is provided between the backup control circuit 8 and the internal power supply circuit 7, and forms a supply path for supplying the backup power (output voltage V2) from the backup control circuit 8 to the internal power supply circuit 7 when the output voltage V1 is abnormal. The diode D3 is provided between the output terminal T5 and the standby control circuit 8, and forms a supply path for supplying the output voltage V2 of the 2 nd converter 102 to the standby control circuit 8. In addition, the diode D3 may be omitted.
The control unit 9 is constituted by a microcomputer, and controls the operations of the 1 st converter 101, the 2 nd converter 102, and the standby control circuit 8. The request signal S1 is input and output as an external signal to the control unit 9 from an external device such as an in-vehicle ECU (electronic control unit). The signal S1 is a signal for requesting the operation of the 2 nd converter 102, and corresponds to the "1 st signal" in the present invention. The control unit 9 receives the output request signal S1 and outputs the output permission signal S2 to the 2 nd converter 102. The signal S2 is a signal for permitting the operation of the 2 nd converter 102, and corresponds to the "2 nd signal" in the present invention. When the voltage detection circuit 6 detects that the output voltage V1 has disappeared or dropped, the control unit 9 outputs the standby command signal S3 to the standby control circuit 8. The signal S3 is a signal for turning on a switching element (described later) included in the standby control circuit 8, and corresponds to a "3 rd signal" in the present invention.
The 1 st converter 101 has an input filter 1, a switching circuit 2, an insulation transformer 3, a rectifying circuit 4, and a smoothing circuit 5. Since the structures of these portions are well known and the 1 st transducer 101 itself is not directly related to the present invention, a detailed description of the 1 st transducer 101 is omitted. The 1 st converter 101 of this example is an insulated DC-DC converter in which an input side and an output side are insulated by an insulation transformer 3.
The 2 nd converter 102 includes a switching circuit 20, an insulation transformer 21, a main winding side rectifying circuit 22, an auxiliary winding side rectifying circuit 23, an insulation circuit 26, a PWM (Pulse Width Modulation: pulse width modulation) circuit 27, and a feedback circuit 28. As described above, the 2 nd converter 102 has a function of stepping down and outputting the dc voltage Vi input to the input terminals T1 and T2, and a function of supplying the standby power to the control unit 9 when the 1 st converter 101 has an abnormal output. The 2 nd converter 102 of this example is also an insulated DC-DC converter in which the input side and the output side are insulated by the insulation transformer 21. In fig. 1, the circuit of the subsequent stage of the auxiliary winding side rectifier circuit 23 is omitted.
Fig. 2 shows a specific circuit of the switching circuit 20, the insulation transformer 21, and the main winding side rectifying circuit 22 of the 2 nd converter 102. In addition, a specific circuit of the standby control circuit 8 is also shown in fig. 2. The circuit shown here is an example, and the present invention is not limited to these. In fig. 2, the rectifier circuit 23 and the insulation circuit 26 on the auxiliary winding side in the block constituting the 2 nd converter 102 of fig. 1 are omitted.
The switching circuit 20 has a switching element Q3. In this example, the switching element Q3 is an FET (field effect transistor) connected between the primary winding La of the insulation transformer 21 and the ground terminal. The gate of the switching element Q3 is connected to the PWM circuit 27, and the switching element Q3 performs on/off operation in accordance with a PWM signal supplied from the PWM circuit 27 to the gate.
The insulation transformer 21 has a primary winding La and secondary windings Lb, lc. In the secondary winding, the winding Lb is a main winding, and the winding Lc is an auxiliary winding. Since the auxiliary winding Lc is not directly related to the present invention, the circuit of the latter stage of the winding is omitted. The primary side and the secondary side of the insulation transformer 21 are electrically insulated. The input voltage Vi applied to the primary winding La is switched by turning on/off the switching element Q3, becomes an ac voltage (pulse voltage), and is transmitted to the secondary windings Lb, lc of the insulation transformer 21.
The rectifier circuit 22 provided at the subsequent stage of the secondary winding Lb has a diode D4 and a capacitor C1. The diode D4 is a rectifier diode for rectifying the ac voltage generated in the secondary winding Lb to a dc voltage. The capacitor C1 is an output capacitor for smoothing the dc voltage rectified by the diode D4 and outputting the smoothed dc voltage from the output terminals T5 and T6. The diode D4 is connected between one end of the secondary winding Lb and the output terminal T5, and the capacitor C1 is connected between the output terminals T5 and T6.
The standby control circuit 8 has a 1 st transistor Q1, a 2 nd transistor Q2, and a resistor R1. The 1 st transistor Q1 is provided between the output terminal T5 and the control unit 9, and forms a supply path for supplying the output voltage V2 of the 2 nd converter 102 to the control unit 9. The 2 nd transistor Q2 is provided between the base of the 1 st transistor Q1 and the ground terminal, and is turned on in response to the standby command signal S3 from the control unit 9, thereby turning on the 1 st transistor Q1. Resistor R1 is a base resistor connected to the base of 1 st transistor Q1. The 1 st transistor Q1 corresponds to the "1 st switching element" in the present invention, and the 2 nd transistor Q2 corresponds to the "2 nd switching element" in the present invention.
The emitter of the 1 st transistor Q1 is connected to the output terminal T5 via the diode D3. The collector of the 1 st transistor Q1 is connected to the internal power supply circuit 7 (fig. 1) via the diode D2. The base of the 1 st transistor Q1 is connected to the collector of the 2 nd transistor Q2 via a resistor R1. The base of the 2 nd transistor Q2 is connected to the control unit 9, and the emitter of the 2 nd transistor Q2 is grounded to the ground. A discharge path of the capacitor C1 is formed by the 1 st transistor Q1 and the 2 nd transistor Q2. This will be described in detail later.
Returning to fig. 1, the insulation circuit 26 is a circuit for electrically insulating the output permission signal S2 outputted from the control unit 9 and transmitting it to the PWM circuit 27, and is constituted by an isolator.
The PWM circuit 27 receives the output permission signal S2 from the insulation circuit 26, generates a PWM signal having a predetermined duty ratio, and outputs the PWM signal to the switching circuit 20. As described above, the PWM signal is supplied to the gate of the switching element Q3 (fig. 2). The feedback circuit 28 compares the output voltage V2 of the 2 nd converter 102 with a target value, and performs feedback control on the PWM circuit 27 so that the output voltage V2 coincides with the target value. That is, feedback control is performed in the following manner: the duty ratio of the PWM signal is adjusted down when the output voltage V2 is higher than the target value, and the duty ratio of the PWM signal is increased when the output voltage V2 is lower than the target value.
Next, in the switching power supply device 100 having the above configuration, a problem associated with restarting the 2 nd converter 102 and a countermeasure thereof will be described.
First, a problem associated with restarting of the 2 nd converter 102 will be described with reference to fig. 5 and 6. In the timing chart of fig. 6, (a) represents the output voltage V2 of the 2 nd converter 102, (b) represents the output request signal S1 externally input to the control unit 9, (c) represents the output permission signal S2 output from the control unit 9, and (d) represents the standby command signal S3 output from the control unit 9. t1 to t4 represent time. The "H" (high) of the signals S1 to S3 indicates a state of the output signal, and the "L" (low) indicates a state of the non-output signal.
In the period from time t1 to time t2, the output request signal S1 is "H", and the output permission signal S2 is also "H" when receiving the output request signal. In this section, the PWM circuit 27 is driven based on the output permission signal S2 output from the control unit 9, and the 2 nd inverter 102 is in an operating state.
When the output request signal S1 becomes "L" at time t2, the output permission signal S2 also becomes "L" upon receiving the signal. That is, the output permission signal S2 is not outputted from the control unit 9, and the 2 nd converter 102 is in the non-operating state. After the non-operation state continues for the time W1, when the output request signal S1 becomes "H" again at time t3, the output permission signal S2 also becomes "H" in response thereto. Therefore, the 2 nd converter 102 is again in the operating state according to the output permission signal S2 outputted from the control unit 9. That is, at time t3, the 2 nd converter 102 is restarted.
Here, when the time W1 until the 2 nd converter 102 is restarted is short, at the time of restarting (time t 3), an overvoltage Z as shown in fig. 6 (a) is generated in the output of the 2 nd converter 102. This is because, since the time W1 is short, the charge of the capacitor C1 of the rectifier circuit 22 cannot be completely discharged during this time. The details thereof are described below.
Fig. 5 shows a circuit state at the time (time t 3) when the 2 nd converter 102 is restarted. Since the output permission signal S2 of "H" is supplied to the PWM circuit 27 at the time of restarting, the switching element Q3 of the switching circuit 20 is turned on and off by the PWM circuit 27. Thereby, the 2 nd converter 102 is in an operating state. On the other hand, at the time point when the output permission signal S2 is no longer output (time t 2), the standby command signal S3 remains "L" as shown in fig. 6 (d), and this state is not changed even when the 2 nd converter 102 is restarted (time t 3). Therefore, since the standby command signal S3 is not output during the period from time t2 to t3 (time W1), both the 1 st transistor Q1 and the 2 nd transistor Q2 of the standby control circuit 8 are turned off as shown in fig. 5. Therefore, if the time W1 until the 2 nd converter 102 is restarted is short, the charge of the capacitor C1 is not discharged, and the voltage across the capacitor C1 is maintained in a high state, so this is represented as an overvoltage Z at the time of restarting ((a) of fig. 6).
Next, a solution to the above problem according to the present invention will be described with reference to fig. 3 and 4.
In the present invention, as shown in fig. 4 c, during a predetermined period of time W2 (W2 > W1) from the time point (time t 2) when the request signal S1 is no longer input to and output from the control unit 9, the output permission signal S2 is maintained at "L" even when the request signal S1 is input to and output from the control unit 9 again at time t 3. That is, during this period, the control unit 9 prohibits the output of the output permission signal S2. As shown in fig. 4 (d), the standby command signal S3 is "H" for a predetermined period of time W2. That is, during this period, the control unit 9 outputs the standby command signal S3.
Fig. 3 shows the circuit state at time W2 (time t2 to t 4) of fig. 4. During this period, the output permission signal S2 is "L", and the output permission signal S2 is not supplied to the PWM circuit 27, so that the PWM circuit 27 does not operate. Therefore, the switching element Q3 of the switching circuit 20 is turned off, and the 2 nd converter 102 stops operating. On the other hand, during the time W2, the standby command signal S3 is "H", and the standby command signal S3 is supplied from the control unit 9 to the standby control circuit 8, so that both the 1 st transistor Q1 and the 2 nd transistor Q2 of the standby control circuit 8 are turned on.
When the two transistors Q1 and Q2 are turned on, a discharge path of the electric charge stored in the capacitor C1 as indicated by a bold arrow in fig. 3 is formed. Specifically, the charge of the capacitor C1 is discharged in a path of the capacitor c1→the diode d3→the emitter of the 1 st transistor Q1→the base resistor r1→the collector of the 2 nd transistor Q2→the emitter of the 2 nd transistor Q2→the ground terminal.
In this case, by appropriately selecting the time constant of the discharge path, the discharge of the capacitor C1 can be completed within the time W2 of fig. 4, that is, during the period in which the transistors Q1 and Q2 of the standby control circuit 8 are turned on. Further, even if the output request signal S1 becomes "H" at time t3, the 2 nd converter 102 is not restarted at that time, and therefore, at time t3, the overvoltage Z as in fig. 6 (a) does not occur in the output of the 2 nd converter 102.
Thereafter, at the time point when the time W2 has elapsed (time t 4), when the output request signal S1 is "H", that is, when the output request signal S1 is input to the control unit 9, the control unit 9 outputs the output permission signal S2 again as shown in fig. 4 (c), and the control unit 9 stops the output of the standby command signal S3 as shown in fig. 4 (d). Based on the output permission signal S2 output from the control unit 9, as shown in fig. 4 (a), the 2 nd converter 102 is restarted at time t4. At this time, as described above, the discharge of the charge of the capacitor C1 is completed, and thus, no overvoltage is generated in the output of the 2 nd converter 102. At time t4, the output of the standby command signal S3 from the control unit 9 disappears, and the transistors Q1 and Q2 of the standby control circuit 8 are switched from on to off.
As described above, in the above embodiment, even if the output request signal S1 is input again during the predetermined time W2 from the time point (time t 2) when the input of the output request signal S1 to the control unit 9 is lost, the control unit 9 prohibits the output of the output permission signal S2, and the control unit 9 outputs the standby command signal S3 to put the standby control circuit 8 into the operation state. Then, before a certain time W2 elapses, the charge of the capacitor C1 provided in the rectifier circuit 22 is discharged via the backup control circuit 8.
Therefore, even if the time W1 from the stop of the output request signal S1 to the re-input is short, the 2 nd converter 102 is not restarted during the constant time W2 when the output permission signal S2 is not output, and the charge of the capacitor C1 is discharged by the standby control circuit 8 during this time. As a result, the 2 nd converter 102 does not generate an overvoltage at the time of restarting (time t 4).
The transistors Q1 and Q2 of the standby control circuit 8 are originally members for supplying the output voltage V2 of the 2 nd converter 102 to the control unit 9 as a standby power supply, but in the above embodiment, these transistors Q1 and Q2 are used as the discharging paths of the capacitor C1. Therefore, it is not necessary to provide a dedicated discharge circuit in addition to the standby control circuit 8, and an increase in the number of components can be suppressed, thereby realizing the low-cost switching power supply device 100.
In the present invention, various embodiments other than the above-described embodiments can be adopted.
In the above embodiment, as shown in fig. 4 (d), the period in which the standby command signal S3 is output is the same as the period W2 in which the output permission signal S2 is stopped, but the period in which the standby command signal S3 is output may be a period shorter than W2 and longer than W1. The standby command signal S3 may be output only during W1.
In the above embodiment, the 1 st converter 101 and the 2 nd converter 102 are both buck-type DC-DC converters, but each of the converters 101 and 102 may be a boost-type DC-DC converter. In addition, one of the converters 101 and 102 may be a step-down DC-DC converter, and the other may be a step-up DC-DC converter.
In the above embodiment, the example was given in which the 1 st converter 101 and the 2 nd converter 102 are both insulated DC-DC converters, but each converter 101, 102 may be a non-insulated DC-DC converter.
In the above embodiment, as shown in fig. 1, the voltage detection circuit 6 and the internal power supply circuit 7 are provided separately from the control section 9, but the voltage detection circuit 6 and the internal power supply circuit 7 may be incorporated in the control section 9.
In the above embodiment, the PWM circuit 27 is exemplified as the driving circuit for driving the switching circuit 20, but a driving circuit for driving the switching circuit 20 by a method other than PWM may be provided.
In the above embodiment, the transistors Q1 and Q2 are exemplified as the switching elements included in the standby control circuit 8, but FETs, relays, or the like may be used instead of the transistors.
In the above-described embodiment, the switching power supply device 100 mounted on the vehicle is exemplified, but the switching power supply device of the present invention can be applied to applications other than vehicles.
Claims (5)
1. A switching power supply device has a switching element,
an input terminal to which a direct-current voltage is input;
a 1 st converter that converts a direct-current voltage input to the input terminal into a direct-current voltage of a predetermined voltage value;
a 2 nd converter that converts a direct-current voltage input to the input terminal into a direct-current voltage having a voltage value different from the predetermined voltage value;
a 1 st output terminal that outputs the direct-current voltage converted by the 1 st converter;
a 2 nd output terminal outputting the dc voltage converted by the 2 nd converter;
a control unit that operates with the output voltage of the 1 st converter as a power source, and drives the 2 nd converter in accordance with a 1 st signal supplied from the outside; and
a standby control circuit for supplying the output voltage of the 1 st converter to the control unit as a standby of the power supply of the control unit when the output voltage of the 1 st converter disappears or drops,
the 2 nd converter includes: a switching circuit that switches a direct-current voltage input to the input terminal; and a rectifying circuit rectifying the voltage switched by the switching circuit,
the switch circuit operates according to a 2 nd signal outputted by the control unit based on the 1 st signal, and the backup control circuit operates according to a 3 rd signal outputted by the control unit when the output voltage of the 1 st converter disappears or drops,
it is characterized in that the method comprises the steps of,
during a predetermined period of time from the moment when the input of the 1 st signal is lost, even if the 1 st signal is input again, the control unit prohibits the output of the 2 nd signal, and the 3 rd signal is output to put the standby control circuit into an operation state,
before the lapse of the certain time, the charge of the capacitor of the rectifying circuit is discharged via the standby control circuit.
2. The switching power supply device according to claim 1, wherein,
when the 1 st signal is input at a timing when the predetermined time has elapsed, the control unit outputs the 2 nd signal and stops the output of the 3 rd signal.
3. Switching power supply device according to claim 1 or 2, characterized in that,
the switching power supply device further includes:
a driving circuit that drives the switching circuit according to the 2 nd signal from the control unit; and
a feedback circuit that performs feedback control for the driving circuit based on an output voltage of the 2 nd converter,
during the predetermined period, the output of the 2 nd signal is inhibited, the drive circuit and the switch circuit are in a non-operating state, and the 2 nd converter is stopped, and in this state, the charge of the capacitor is discharged via the standby control circuit.
4. Switching power supply device according to claim 1 or 2, characterized in that,
the standby control circuit includes:
a 1 st switching element forming a supply path for supplying an output voltage of the 2 nd converter to the control section; and
a 2 nd switching element which is turned on in accordance with the 3 rd signal from the control section, thereby turning on the 1 st switching element,
a discharge path of the capacitor is formed by the 1 st switching element and the 2 nd switching element.
5. The switching power supply unit according to claim 4, wherein,
the 1 st switching element is a 1 st transistor provided between the 2 nd output terminal and the control section,
the 2 nd switching element is a 2 nd transistor arranged between the base of the 1 st transistor and ground,
the discharge path is a discharge path from the emitter of the 1 st transistor to a ground terminal via the collector and emitter of the 2 nd transistor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019116013A JP7198163B2 (en) | 2019-06-24 | 2019-06-24 | switching power supply |
| JP2019-116013 | 2019-06-24 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112134447A CN112134447A (en) | 2020-12-25 |
| CN112134447B true CN112134447B (en) | 2023-07-25 |
Family
ID=73850552
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010572554.4A Active CN112134447B (en) | 2019-06-24 | 2020-06-22 | Switching power supply device |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP7198163B2 (en) |
| CN (1) | CN112134447B (en) |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05191973A (en) * | 1991-07-12 | 1993-07-30 | Nec Corp | Dc-dc converter |
| JPH11164555A (en) * | 1997-11-27 | 1999-06-18 | Tdk Corp | Switching power supply |
| JP2003125578A (en) * | 2001-10-15 | 2003-04-25 | Fuji Electric Co Ltd | Switching power unit |
| JP2004215356A (en) * | 2002-12-27 | 2004-07-29 | Toyota Industries Corp | Switching power supply |
| JP2004215411A (en) * | 2003-01-06 | 2004-07-29 | Densei Lambda Kk | Power factor improvement method of power supply system, power supply system, switching power supply, and uninterruptible power supply |
| JP2008125249A (en) * | 2006-11-13 | 2008-05-29 | Densei Lambda Kk | Power supply unit |
| JP2010098869A (en) * | 2008-10-17 | 2010-04-30 | Nichicon Corp | Switching power supply device |
| JP2011135702A (en) * | 2009-12-24 | 2011-07-07 | Sharp Corp | Switching power supply |
| JP2014240854A (en) * | 2013-06-11 | 2014-12-25 | シャープ株式会社 | Liquid crystal display device and television device |
| JP2016111724A (en) * | 2014-12-02 | 2016-06-20 | 株式会社東芝 | Dc power supply device |
| JP2016171686A (en) * | 2015-03-13 | 2016-09-23 | 新電元工業株式会社 | Control circuit and switching power supply |
| JP2018088823A (en) * | 2018-03-07 | 2018-06-07 | ローム株式会社 | Comparison circuit, power supply control ic and switching power supply device |
| JP2018174633A (en) * | 2017-03-31 | 2018-11-08 | サンケン電気株式会社 | Switching power supply device |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100597379B1 (en) * | 2002-02-08 | 2006-07-10 | 산켄덴키 가부시키가이샤 | Method for starting power source apparatus, circuit for starting power source apparatus, power source apparatus |
| JP2004222485A (en) * | 2002-12-27 | 2004-08-05 | Sony Corp | Switching power supply circuit |
| JP5843836B2 (en) * | 2012-11-30 | 2016-01-13 | キヤノン株式会社 | Power supply circuit |
| US10236715B2 (en) * | 2015-09-23 | 2019-03-19 | Dexin Liang | Switch power circuit with backup battery for power supply |
| CN109643955B (en) * | 2016-08-30 | 2021-03-12 | 新唐科技日本株式会社 | Switching power supply device and semiconductor device |
-
2019
- 2019-06-24 JP JP2019116013A patent/JP7198163B2/en active Active
-
2020
- 2020-06-22 CN CN202010572554.4A patent/CN112134447B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05191973A (en) * | 1991-07-12 | 1993-07-30 | Nec Corp | Dc-dc converter |
| JPH11164555A (en) * | 1997-11-27 | 1999-06-18 | Tdk Corp | Switching power supply |
| JP2003125578A (en) * | 2001-10-15 | 2003-04-25 | Fuji Electric Co Ltd | Switching power unit |
| JP2004215356A (en) * | 2002-12-27 | 2004-07-29 | Toyota Industries Corp | Switching power supply |
| JP2004215411A (en) * | 2003-01-06 | 2004-07-29 | Densei Lambda Kk | Power factor improvement method of power supply system, power supply system, switching power supply, and uninterruptible power supply |
| JP2008125249A (en) * | 2006-11-13 | 2008-05-29 | Densei Lambda Kk | Power supply unit |
| JP2010098869A (en) * | 2008-10-17 | 2010-04-30 | Nichicon Corp | Switching power supply device |
| JP2011135702A (en) * | 2009-12-24 | 2011-07-07 | Sharp Corp | Switching power supply |
| JP2014240854A (en) * | 2013-06-11 | 2014-12-25 | シャープ株式会社 | Liquid crystal display device and television device |
| JP2016111724A (en) * | 2014-12-02 | 2016-06-20 | 株式会社東芝 | Dc power supply device |
| JP2016171686A (en) * | 2015-03-13 | 2016-09-23 | 新電元工業株式会社 | Control circuit and switching power supply |
| JP2018174633A (en) * | 2017-03-31 | 2018-11-08 | サンケン電気株式会社 | Switching power supply device |
| JP2018088823A (en) * | 2018-03-07 | 2018-06-07 | ローム株式会社 | Comparison circuit, power supply control ic and switching power supply device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2021002951A (en) | 2021-01-07 |
| JP7198163B2 (en) | 2022-12-28 |
| CN112134447A (en) | 2020-12-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109168326B (en) | Power supply device | |
| US10236776B2 (en) | Inter-supply bidirectional DC-DC converter of a non-insulation type | |
| US7586296B2 (en) | Power supply apparatus | |
| KR100468884B1 (en) | DC-DC Converter | |
| JP2010119257A (en) | Power supply device and vehicle | |
| US9762116B2 (en) | Voltage conversion apparatus | |
| JP2019030116A (en) | Power system | |
| US7068020B2 (en) | Step-down DC—DC converter | |
| US20110242723A1 (en) | Relay driver circuit | |
| JP4086751B2 (en) | Switching power supply | |
| CN112134447B (en) | Switching power supply device | |
| WO2021070506A1 (en) | Dc/dc converter | |
| KR102338378B1 (en) | Battery charging system of vehicle | |
| JP7184711B2 (en) | switching power supply | |
| JP7426397B2 (en) | Power electronic devices and methods for supplying voltage to drive circuits of power semiconductor switches | |
| US10447163B2 (en) | DC/DC converter | |
| KR102159264B1 (en) | Control system to control DC-DC voltage converter circuit | |
| JP6665795B2 (en) | Voltage converter | |
| JP7186683B2 (en) | switching power supply | |
| US11671048B2 (en) | Multiphase voltage transformer for a supply network and method for powering down an intermediate circuit voltage of this supply network | |
| JP4449575B2 (en) | Battery charger | |
| JP2016178730A (en) | Power supply apparatus for motor vehicle and control method therefor | |
| CN116998106A (en) | Motor control device | |
| JP2020092549A (en) | Power supply circuit | |
| JP2010193619A (en) | Drive control device for resonance type step-up/step-down converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |