TWI601366B - A power supply and voltage calibration method - Google Patents

Description

Power supply and voltage correction method

The present invention relates to a calibration method, and more particularly to a voltage calibration method and a power supply implementing the voltage calibration method.

In general, there are differences in the parameters of all components, such as process error, especially the voltage across the capacitors of the Power Supply Unit (PSU), which may not only affect the performance of the power supply, but also reduce the power supply. The reliability of the product, as well as the design must also overcome the problem of insufficient cross-pressure on the capacitor by preserving more margin. In the technical field of power supplies, this capacitor is often referred to as a Bulk Capacitor, and the voltage across the capacitor is commonly referred to as Bulk Voltage.

When the conventional power supply is manufactured, the actual value of the voltage across the capacitor can be measured on the production line, and the error is compensated to complete the calibration to solve the problem that the voltage across the capacitor is not accurate enough. However, since the voltage across the capacitor is usually not directly measured at the output of the power supply, the chassis of the power supply must be turned on to measure. This action may not only cause problems on the production line. Hazards (because of high voltage shocks) can also cause damage to the power supply and waste manufacturing time on the production line. In addition, the conventional power supply has been calibrated even on the production line, but the cross-voltage on the capacitor may be mutated due to other abnormal factors, which again leads to a decrease in performance and reliability.

Accordingly, it is an object of the present invention to provide a power supply and voltage correction method with high reliability.

Thus, in accordance with one aspect of the present invention, a power supply is provided that includes a DC-to-DC boost converter, a capacitor, a DC-to-DC buck converter, and a control unit.

The DC-to-DC boost converter receives an input voltage and converts the input voltage to output a converter output voltage. The capacitor has a first end electrically connected to the DC-to-DC boost converter and a second end connected to the ground, and receives the converter output voltage. The DC-to-DC buck converter is electrically connected to the DC-to-DC boost converter and the first end of the capacitor to receive the converter output voltage, and convert the converter output voltage to output a DC output voltage .

The control unit is electrically connected to the DC-to-DC boost converter to receive the input voltage and the converter output voltage, respectively. When the DC-to-DC boost converter is turned off, the control unit separately samples the input voltage and the converter output voltage, and after determining that the input voltage and the converter output voltage are stable, at least according to the input The input voltage calculates a calculated value corresponding to the output voltage of the converter, and a correction parameter is determined according to the calculated value and the output voltage of the converter. When the DC-to-DC boost converter is turned on, the control unit calculates a correction value according to the calibration parameter and the sampling value of the converter output voltage, and transmits the correction value to the DC-to-DC boost converter. Compensating for the output voltage of the DC-to-DC boost converter.

In some implementations, the DC-to-DC boost converter includes a boost inductor, a boost diode, and a boost switch. The boost inductor includes a first end receiving the input voltage and a second end. The boost diode includes a first end electrically coupled to the second end of the boost inductor and a second end electrically coupled to the first end of the capacitor. The boost switch includes a first end electrically connected to the second end of the boost inductor and a grounded second end.

In some implementations, wherein the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, where V _peak is the peak value of the input voltage, and V _Trace is the input voltage via the boost The magnitude of the loop voltage drop of the inductor and the boost diode, the charging path for charging the capacitor.

V ₁ =V _peak -V _Trace

In other implementations, the power supply further includes a bypass circuit including a first end receiving the input voltage, and a second end electrically connected to the first end of the capacitor, and The DC to DC boost converters are placed in parallel.

In other implementations, wherein the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, where V _peak is the peak value of the input voltage, and V _Trace is the input voltage via the side Circuit circuit, the magnitude of the loop voltage drop of the charging path that charges the capacitor.

V ₁ =V _peak -V _Trace

In some implementations, the peak value V _{peak of} the input voltage may be directly obtained by sampling the input voltage, or the control unit may sample the effective value V _{rms of} the input voltage by using the following formula. Calculated indirectly.

In some implementations, wherein the control unit calculates the correction parameter (Slope) according to the following formula, wherein V ₂ is a sample value of the converter output voltage of the control unit.

In some implementations, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, where V _{Bulk (Sample)} is when the DC-DC boost converter is turned on by the control unit The sampled value of the converter output voltage.

V _Bulk(Result) =S lope *V _Bulk(Sample)

In other implementations, wherein the control unit calculates the correction parameter (Slope) according to the following formula, and further calculates an offset parameter (Offset) according to another formula, wherein V ₁₁ and V ₂₁ are in one At the first time point, the control unit respectively calculates the calculated value (V ₁₁ ) corresponding to the converter output voltage, and the sampled value (V ₂₁ ) of the converter output voltage, V ₁₂ and V ₂₂ are in a At two time points, the control unit calculates the calculated value (V ₁₂ ) corresponding to the converter output voltage and the sampled value (V ₂₂ ) of the converter output voltage.

Offset=V ₁₁ -V ₂₁ * Slope

In other implementations, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, where V _{Bulk (Sample)} is when the control unit is turned on by the DC-DC boost converter The sampled value of the converter output voltage.

V _Bulk(Result) =S lope *V _Bulk(Sample) +O ffset

In other implementations, the power supply further includes a resistor and a switching element. The resistor and the switching element are connected in parallel and are electrically connected to the DC-to-DC boost converter, wherein the charging path for charging the capacitor by the input voltage further includes the switching element and the resistor, such that V _Trace is the input And a voltage is passed through the switching element and the resistor, the boost inductor, and the boost diode, or V _Trace is the input voltage via the switching element and the resistor, and the bypass circuit The magnitude of the loop drop in the charging path for capacitor charging.

In other implementations, the power supply is adapted to receive an AC input voltage, and further comprising a rectifier, wherein the rectifier is electrically coupled to the DC-to-DC boost converter and receives the AC input voltage, and The AC input voltage is converted and output as the input voltage, and the input voltage is a DC input voltage.

In other implementations, V _Trace is a magnitude of a loop voltage drop of a charging path of the input voltage via the rectifier, the boost inductor, and the boost diode to charge the capacitor. Alternatively, V _Trace is the magnitude of the loop voltage drop of the charging path for charging the capacitor via the rectifier and the bypass circuit.

In other implementations, the power supply further includes a resistor and a switching element. The resistor and the switching element are connected in parallel and are electrically connected between the rectifier and the DC-to-DC boost converter, wherein the charging path for charging the capacitor by the input voltage further includes the switching element and the resistor, so that V _Trace is the input voltage via the rectifier, the switching element and the resistor, the boost inductor, and the boost diode, or V _Trace is the AC input voltage via the rectifier, the switching element, and the The resistor, and the bypass circuit, the magnitude of the loop voltage drop of the charging path that charges the capacitor. The magnitude of the loop drop in the charging path that charges the capacitor.

According to another aspect of the present invention, a voltage correction method is provided for use in a power supply. The power supply includes a DC-to-DC boost converter, a capacitor, a DC-to-DC buck converter, and a control unit. The DC-to-DC boost converter receives an input voltage and converts the output to a converter output voltage. The capacitor is electrically coupled to the DC to DC boost converter to receive the converter output voltage. The DC-to-DC buck converter is electrically connected to the DC-to-DC boost converter and the capacitor to receive the converter output voltage and converted to output as a DC output Pressure. The control unit is electrically coupled to the DC-to-DC boost converter to receive the input voltage and the converter output voltage. The voltage correction method is implemented by the control unit and includes the following steps: (a) when the DC-to-DC boost converter is turned off, the control unit separately samples the input voltage and the converter output voltage; (b) The control unit determines whether the input voltage and the converter output voltage are stable, and repeats the step (a) when the input voltage and the converter output voltage are not stabilized; and (c) when the control unit determines the input voltage and the When the converter output voltage has stabilized, the control unit calculates a calculated value corresponding to the converter output voltage according to the input voltage, and determines a correction parameter according to the calculated value and the converter output voltage.

In some implementations, the voltage correction method further includes the step (k) before the step (a) and the step (d) after the step (c): (k) when the DC-to-DC boost converter is turned on. The control unit sends a signal to the DC-to-DC boost converter to turn off the DC-to-DC boost converter; and (d) when the DC-to-DC boost converter is turned on, the control unit corrects according to the correction The parameter and the sampled value of the converter output voltage, calculate a correction value, and transmit the correction value to the DC-to-DC boost converter to compensate the output voltage of the DC-to-DC boost converter.

In some implementations, wherein, in step (c), the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, where V _peak is the peak value of the input voltage, and V _Trace is The input voltage is via a boost diode of the DC-to-DC boost converter, and the magnitude of the loop voltage drop of the charging path that charges the capacitor.

V ₁ =V _peak -V _Trace

In some implementations, in step (c), the peak value V _{peak of} the input voltage may be obtained directly by the control unit by sampling the input voltage, or may be the control unit sampling the input voltage. After the effective value V _rms , it is obtained indirectly by the following formula.

In some implementations, wherein in step (c), the control unit calculates the correction parameter Slope according to the following formula, wherein V ₂ is a sampled value of the converter output voltage by the control unit.

In some implementations, wherein, in step (d), the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, wherein V _{Bulk (Sample)} is the DC voltage boost of the control unit A sample of the output voltage to the converter when the converter is turned on.

V _Bulk(Result) =S lope *V _Bulk(Sample)

In other implementations, wherein the control unit calculates the correction parameter (Slope) according to the following formula, and further calculates an offset parameter (Offset) according to another formula, wherein V ₁₁ and V ₂₁ are in one At the first time point, the control unit respectively calculates the calculated value (V ₁₁ ) corresponding to the converter output voltage, and the sampled value (V ₂₁ ) of the converter output voltage, V ₁₂ and V ₂₂ are in a At two time points, the control unit calculates the calculated value (V ₁₂ ) corresponding to the converter output voltage and the sampled value (V ₂₂ ) of the converter output voltage.

Offset=V ₁₁ -V ₂₁ * Slope

In other implementations, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, where V _{Bulk (Sample)} is when the control unit is turned on by the DC-DC boost converter The sampled value of the converter output voltage.

V _Bulk(Result) =S lope *V _Bulk(Sample) +O ffset

In other implementations, the power supply further includes a resistor and a switching element. The resistor and the switching element are connected in parallel and are electrically connected to the DC-to-DC boost converter. The bypass circuit receives the input voltage via the resistor and the switching element. Wherein, in the step (c), the charging path for charging the capacitor by the input voltage further comprises the switching element and the resistor, such that V _Trace is the input voltage via the switching element and the resistor, and the DC-DC The boost diode of the boost converter, the magnitude of the loop voltage drop of the charging path that charges the capacitor.

The present invention has at least the following effects: the voltage correction method is implemented by the control unit of the power supply, and the DC-to-DC voltage boost converter is turned off. In the case of the control unit, using simple signal sampling and numerical calculation, the effective calibration parameter and the correction value can be obtained to control the DC-to-DC boost converter to adjust the output voltage of the converter. The setting makes the actual measured value of the converter output voltage remain unchanged, so that the DC output voltage of the DC-to-DC buck converter remains unchanged, and the reliability of the power supply can be improved.

1‧‧‧AC power supply

2‧‧‧Rectifier

3‧‧‧Switching elements

4‧‧‧DC to DC Boost Converter

41‧‧‧Boost Inductors

42‧‧‧Boost diode

43‧‧‧Boost switch

5‧‧‧DC to DC Buck Converter

6‧‧‧Control unit

7‧‧‧Bypass circuit

9‧‧‧Power supply

V _s ‧‧‧AC input voltage

V _in ‧‧‧DC input voltage

V _Bulk ‧‧‧ converter output voltage

V _out ‧‧‧DC output voltage

R ₁ ‧‧‧Resistors

C ₁ ‧‧‧ capacitor

S0~S5‧‧‧Steps

Other features and advantages of the present invention will be apparent from the embodiments of the present invention. FIG. 1 is a block diagram illustrating an embodiment of the power supply of the present invention. FIG. 2 is a timing diagram illustrating The relationship between the input and the output of a rectifier of this embodiment; FIG. 3 is a flow chart illustrating the voltage correction method performed by the embodiment of the present invention; and FIG. 4 is a timing chart illustrating another application of the embodiment. A way of doing it.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

Referring to FIG. 1, an embodiment of a power supply 9 of the present invention is adapted to electrically connect an AC power source 1 to receive an AC input voltage V _s and includes a rectifier 2 and a DC-to-DC boost converter (DC/DC). Boost Converter) 4, a capacitor C ₁ , a bypass circuit 7 , a resistor R ₁ , a switching element 3 , a DC/DC Step-Down Converter 5 , and A control unit 6.

Referring to FIG. 1 and FIG. 2, the rectifier 2 receives the AC input voltage V _s and converts the AC input voltage V _s to output a DC input voltage V _in . In this embodiment, the rectifier 2 is a bridge full-wave rectifier, and converts the portion of the AC input voltage V _s (shown in FIG. 2 ) whose voltage value is less than zero into a positive value and the amplitude remains unchanged. The output is the DC input voltage V _in (as shown _in FIG. 2 ), and in other embodiments, the rectifier 2 may be other types of rectifiers, or the rectifier 2 is omitted.

The resistor R ₁ and the switching element 3 are connected in parallel and are electrically connected between the rectifier 2 and the DC-to-DC boost converter 4 . The resistor R ₁ is used as a current limiting resistor to prevent the inrush current of the power supply 9 at startup. In this embodiment, the switching element 3 is a relay, but is not limited thereto.

The DC-to-DC boost converter 4 is electrically connected to the resistor R ₁ and the switching element 3 to receive the DC input voltage V _in , and converts the DC input voltage V _in to be output as a converter output voltage V _Bulk . It is particularly worth mentioning that the DC-to-DC boost converter 4 is not limited to only boosting the DC input voltage V _in and outputting the converter output voltage V _Bulk , the DC-to-DC boost converter 4 The DC input voltage V _{in may} not be boosted and not stepped down, for example, by maintaining the magnitude of the original output voltage, and outputting the converter output voltage V _Bulk . In addition, the DC-to-DC boost converter 4 can also provide a Power Factor Correction (PFC) function. In this embodiment, the DC-to-DC boost converter 4 includes: a boost inductor including a first end receiving the input voltage, and a second end; and a boost diode including an electric a first end connected to the second end of the boost inductor, and a second end electrically connected to the first end of the capacitor; and a boost switch including a second electrically connected to the boost inductor The first end of the end and the second end of the ground.

The capacitor C ₁ has a first end electrically connected to the DC-to-DC boost converter 4 and a grounded second end, and receives the converter output voltage V _Bulk . In the technical field of power supplies, the capacitor C ₁ is generally referred to as a Bulk capacitor, and the value of the capacitor C ₁ is generally between three hundred and six hundred microfarads (uF), but not limited thereto. The voltage across the two terminals of the capacitor C ₁ is commonly referred to as the Bulk voltage, which is the converter output voltage V _Bulk referred to herein.

The bypass circuit 7 has a first end electrically connected to the rectifier 2 and receiving the DC input voltage V _in , and a second end electrically connected to the first end of the capacitor C ₁ , and the bypass circuit 7 The DC-to-DC boost converter 4 is arranged in parallel. In this embodiment, the bypass circuit 7 is a bypass diode, and an anode terminal and a cathode terminal of the bypass diode are respectively the first end of the bypass circuit 7 and the Second end.

The DC-to-DC buck converter 5 is electrically connected to the first terminal of the DC-DC boost converter 4 and the capacitors C ₁ to receive the converter output voltage V _Bulk, and the converter output voltage V _Bulk The output is converted to a DC output voltage V _out .

Referring to FIG. 1 and FIG. 3, the control unit 6 is electrically connected to the rectifier 2 and the DC-to-DC boost converter 4 to receive the DC input voltage V _in and the converter output voltage V _{Bulk , respectively} . The control unit 6 implements the voltage correction method and includes steps S0 to S5. It is particularly noted that in the present embodiment, the control unit 6 is an element that is independent of the power supply 9, and in other embodiments, the control unit 6 can also be integrated in the power supply 9. Among other components, such as integrated into the DC-to-DC buck converter 5, but not limited to this.

In step S0, the control unit 6 determines whether the DC-to-DC boost converter 4 is turned off. If it is off, step S2 is performed. If it is not turned off (ie, turned on), step S1 is performed.

In step S1, when the step S0 determines that the DC-to-DC boost converter 4 is turned on, the control unit 6 sends a signal to the DC-to-DC boost converter 4 to turn off the DC-DC boost converter 4.

In step S2, when the DC-to-DC boost converter 4 is turned off, the control unit 6 samples (or samples) the DC input voltage V _in and the converter output voltage V _Bulk , respectively.

In step S3, the control unit 6 determines whether the DC input voltage V _in and the converter output voltage V _Bulk are stable. When the DC input voltage V _in and the converter output voltage V _{Bulk are} not stable, step S2 is repeated. When the DC input voltage V _in and the converter output voltage V _Bulk are stabilized, step S4 is performed. More specifically, when the DC input voltage V _{in is} sampled, the control unit 6 continuously detects the effective value (ie, the rms value; rms) of the DC input voltage V _in the predetermined time period and the peak value. ratio, when the ratio remain stable, i.e. the control unit 6 determines, according to the DC input voltage V _in is stabilized. Similarly, when the control unit 6 samples the converter output voltage V _Bulk , it can also continue for a period of time to determine whether it has stabilized.

In step S4, when the control unit 6 determines that the DC input voltage V _in and the converter output voltage V _Bulk have stabilized, the control unit 6 calculates the corresponding converter output voltage V _Bulk according to the DC input voltage V _in at least. A value is calculated, and a correction parameter is determined based on the calculated value and the converter output voltage V _Bulk .

In more detail, the control unit 6 calculates the calculated value V ₁ corresponding to the converter output voltage V _Bulk according to the following formula (1), where V _peak is the _{peak value} of the DC input voltage V _in , V _Trace is The AC input voltage V _s passes through the rectifier 2, the switching element 3, the resistor R ₁ , and the bypass circuit 7 to increase the loop voltage drop of the charging path of the capacitor C ₁ , that is, the circuit voltage drop charging path including the bypass circuit is turned on when the voltage drop 7 of the switching element 3 is turned on when the voltage drop of the resistor R _1, and the pressure drop wire or other element on the charging path. It should be particularly noted that the formula (1) is because the DC-to-DC boost converter 4 remains off (ie, not activated). At this time, the capacitor C ₁ is only used by the rectifier 2 via the aforementioned charging path. Energy is supplied, so the converter output voltage V _Bulk is V ₁ . Furthermore, V _Trace can be evaluated or estimated in advance and stored in the control unit 6 in advance. In addition, the DC input voltage V _in V _peak may be the peak value by the sampling of the DC input voltage V _in is obtained directly. When the AC input voltage V _s is a sine wave (such as the mains or as shown in FIG. 2 ), the peak value V _{peak of} the DC input voltage V _in may also be an effective value of the DC input voltage V _in by the control unit 6 . After V _rms , it is obtained indirectly by the following formula (2). Furthermore, the control unit 6 calculates the correction parameter Slope by the following formula (3), wherein V ₂ is a sampled value of the converter output voltage V _Bulk by the control unit 6 .

V ₁ =V _peak -V _Trace .....(1)

In addition, in this embodiment, the control unit 6 samples the DC input voltage V _in to obtain the peak value V _peak , and in other embodiments, the control unit 6 may also change the AC input voltage V directly. _s sampling to obtain the peak value V _peak . Furthermore, in the embodiment, the power supply 9 includes the resistor R ₁ and the switching element 3, while in other embodiments, the power supply 9 may not have the resistor R ₁ and the switch. Element 3, the DC-to-DC boost converter 4 is directly electrically connected to the rectifier 2 to receive the DC input voltage V _in , and V _Trace is the AC input voltage V _s via the rectifier 2 and the bypass circuit 7 The magnitude of the loop voltage drop of the charging path that the capacitor C ₁ charges.

In step S5, when the DC-to-DC boost converter 4 is turned on, for example, the control unit 6 first controls the DC-to-DC boost converter 4 to be turned on, but not limited thereto, the control unit 6 according to the calibration parameter and the A sample value of the converter output voltage is calculated, and a correction value is calculated and output (transmitted) to the DC-to-DC boost converter 4 to compensate the output voltage of the DC-to-DC boost converter 4. In more detail, the correction value V _{Bulk (Result) is} calculated according to the following formula (4 ₎ . Wherein, V _{Bulk (Sample)} is a sampling value of the converter output voltage V _Bulk when the DC-DC boost converter 4 is turned on by the control unit 6 .

V _Bulk(Result) = Slope *V _Bulk(Sample) .....(4)

For example, assuming that all components of the power supply 9 are normal without any error in operation, the DC-to-DC boost converter 4 outputs the converter output voltage V _Bulk to 400V. When the DC-to-DC boost converter 4 is abnormal and there is no correction compensation such that the output voltage V _Bulk of the converter is 390V, the control unit 6 first calculates the calibration parameter by the correction method. And when the DC-to-DC boost converter 4 is turned on, the converter output voltage V _Bulk is sampled to calculate the correction value, and the correction value is transmitted to the DC-to-DC boost converter 4 And controlling the DC-to-DC boost converter 4 to output a converter output voltage V _{Bulk of} 410V, that is, changing the output setting of the DC-to-DC boost converter 4, the actual output voltage of the converter V _Bulk can be generated. effect measured value of 400V, thus making the step-down DC to DC converter of the DC output voltage V 5 is _out remain stable.

It is particularly worth mentioning that, in step S4 of the embodiment, the correction parameter Slope is at a point in time, the control unit 6 respectively calculates the calculated value V ₁ corresponding to the converter output voltage V _Bulk , and The converter output voltage V _Bulk samples the obtained sample value V ₂ and is calculated accordingly. In other embodiments, step S4 may also be that the control unit 6 obtains calculated values and sample values of two time points at two different time points, and calculates the values according to formulas (5) and (6). Correction parameter Slope and an offset parameter Offset. Wherein, when V ₁₁ and V ₂₁ are at a first time point, the control unit 6 respectively calculates the calculated value (V ₁₁ ) corresponding to the output voltage of the converter, and the sampled value of the output voltage of the converter (V ₂₁ ). When V ₁₂ and V ₂₂ are at a second time point, the control unit 6 calculates the calculated value (V ₁₂ ) corresponding to the converter output voltage and the sampled value (V ₂₂ ) of the converter output voltage. Furthermore, in step S5, the control unit 6 calculates the correction value V _{Bulk (Result)} according to the formula (7 ₎ . Wherein, V _{Bulk (Sample)} is a sampling value of the converter output voltage V _Bulk when the DC-DC boost converter is turned on by the control unit 6 .

Offset=V ₁₁ -V ₂₁ * Slope ...(6)

V _Bulk(Result) =S lope *V _Bulk(Sample) +O ffset ...(7)

Referring again to FIG. 1, deserves special mention are: In the present example, the power supply of the switching element 9 comprises 3, the resistor R ₁ and the bypass circuit 7, so that the V _Trace charging the capacitors C ₁ of The charging path includes the switching element 3 and the resistor R ₁ and the bypass circuit 7. In other embodiments, the switching element and the resistor R ₁ may also be omitted, so that the charging path for charging the capacitor C _{1 by} V _{Trace is} changed to include the bypass circuit 7. Alternatively, in other embodiments, the bypass circuit 7 may be omitted, and a boost inductor 41, a boost diode 42 included in the DC-to-DC boost converter 4, And a boost switch 43 such that the charging path for charging the capacitor C _{1 by} V _{Trace is} changed to include the switching element 3 and the resistor R ₁ , the boost inductor 41 , and the boosting diode 42 . Alternatively, in other embodiments, the switching element 3, the resistor R ₁ , and the bypass circuit 7 may be omitted, such that the charging path for charging the capacitor C _{1 by} V _{Trace is} changed to include the boost inductor. 41. The boost diode 42 is not limited to this.

In addition, it is worthy of particular exemplification that the power supply 9 of the present invention can be applied to the following aspects. The first aspect is the production line of the power supply 9, because the DC-to-DC boost converter 4 is kept off at the time of manufacture. The second aspect is that after the power supply 9 is shipped from the factory, the user can use the input/output port (I/O) of the power supply 9 to trigger with time according to a preset communication protocol, such as I2C. (Time Event) or system event (system event), the DC-to-DC boost converter 4 is turned off for correction. Referring again to Figure 4, there is shown a timing diagram illustrating another aspect of the application of this embodiment. 4 is the time, and the vertical axis is the magnitude of the voltage, indicating the waveform relationship between the DC input voltage V _in and the converter output voltage V _Bulk when the power supply 9 is activated. When the power supply 9 is just started, the voltage across the capacitor C ₁ is zero, and the DC-to-DC boost converter 4 is damaged to avoid the surge current (Inrush Current), and the bypass circuit 7 is After the capacitor C _{1 is} charged to a predetermined voltage, the DC-to-DC boost converter 4 is turned on. In detail, between t ₀ and t ₁ , the capacitor C _{1 is} charged via the bypass circuit 7 via the resistor R ₁ . Between t ₁ and t ₂ , when the time is t ₁ , the switching element 3 is turned on, the resistance of the charging path becomes small, and the converter output voltage V _{Bulk is} directly charged to V ₁ . After t ₂ , when the time is t ₂ , the DC-to-DC boost converter 4 is activated, and the converter output voltage V _{Bulk is} boosted to a target voltage. Therefore, in the power supply 9 of such a state, the power supply 9 can be utilized between t ₁ and t ₂ at the time of startup, and the DC-to-DC boost converter 4 is not activated but remains off. The voltage correction method of the present invention completes the correction of the converter output voltage V _Bulk .

In summary, the voltage correction method is performed by the power supply 9 of the present invention, and it is necessary to ensure that the DC-to-DC boost converter 4 is kept off. Therefore, it can be directly applied to the power supply 9 of the present invention when it is manufactured on a production line. In addition, it saves test manpower, equipment, and manufacturing costs to improve the production line automation of power products. Furthermore, can be maintained at the DC output voltage V _out in the case where the system can withstand the load, i.e. in such a closed DC to DC boost converter 4 while still maintaining the output conditions of the DC output voltage V _out, by Correction is performed by the voltage correction method of the present invention, so that the power supply 9 of the present invention can compensate for the variation of the converter output voltage V _Bulk caused by any abnormal factors, thereby providing a high-reliability power supply, so that the present invention can be achieved. The purpose.

However, the above is only the embodiment of the present invention, and the scope of the invention is not limited thereto, and all the equivalent equivalent changes and modifications according to the scope of the patent application and the patent specification of the present invention are still The scope of the invention is covered.

1‧‧‧AC power supply

2‧‧‧Rectifier

3‧‧‧Switching elements

4‧‧‧DC to DC Boost Converter

41‧‧‧Boost Inductors

42‧‧‧Boost diode

43‧‧‧Boost switch

5‧‧‧DC to DC Buck Converter

6‧‧‧Control unit

7‧‧‧Bypass circuit

9‧‧‧Power supply

V _s ‧‧‧AC input voltage

V _in ‧‧‧DC input voltage

V _Bulk ‧‧‧ converter output voltage

V _out ‧‧‧DC output voltage

R ₁ ‧‧‧Resistors

C ₁ ‧‧‧ capacitor

Claims (33)

A power supply comprising: a DC-to-DC boost converter, receiving an input voltage, and converting the input voltage to output as a converter output voltage; a capacitor having an electrical connection to the DC-to-DC boost conversion a first end of the device and a grounded second end, and receiving the converter output voltage; a DC-to-DC buck converter electrically connected to the DC-to-DC boost converter and the first end of the capacitor to Receiving the converter output voltage, converting the converter output voltage to output as a DC output voltage; and a control unit electrically connecting the DC-to-DC boost converter to respectively receive the input voltage and the converter output a voltage, when the DC-to-DC boost converter is turned off, the control unit separately samples the input voltage and the converter output voltage, and after determining that the input voltage and the converter output voltage are stable, at least according to the input voltage Calculating a calculated value corresponding to the output voltage of the converter, and determining a correction parameter according to the calculated value and the output voltage of the converter, when the straight When the DC boost converter is turned on, the control unit calculates a correction value according to the calibration parameter and the sampling value of the converter output voltage, and transmits the correction value to the DC-to-DC boost converter to compensate the DC The output voltage to the DC boost converter. The power supply of claim 1, wherein the DC-to-DC boost converter comprises: a boost inductor includes a first end receiving the input voltage, and a second end; a boost diode comprising a first end electrically connected to the second end of the boost inductor, and a Electrically connecting the second end of the first end of the capacitor; and a boost switch comprising a first end electrically connected to the second end of the boost inductor and a grounded second end. The power supply device of claim 2, wherein the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, V ₁ =V _peak -V _Trace where V _peak is the input voltage The peak value, V _Trace, is the magnitude of the loop voltage drop of the charging path through which the input voltage is charged via the boost inductor and the boost diode. The power supply of claim 1, further comprising a bypass circuit including a first end receiving the input voltage, and a second end electrically connected to the first end of the capacitor, and the DC Set the DC boost converter in parallel. The power supply of claim 4, wherein the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, V ₁ =V _peak -V _Trace where V _peak is the input voltage The peak value, V _Trace, is the magnitude of the loop voltage drop of the charging path through which the input voltage is charged by the bypass circuit. The power supply device of claim 3 or 5, wherein the peak value _{Vpeak of} the input voltage is directly obtained by sampling the input voltage, or the control unit can sample the effective value V _{rms of} the input voltage. After that, indirectly obtained by the following formula The power supply device of claim 6, wherein the control unit calculates the correction parameter (Slope) according to the following formula, Where V ₂ is a sampled value of the output voltage of the converter by the control unit. The power supply device of claim 7, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, V _{Bulk (Result)} = S lope * V _{Bulk (Sample),} wherein V _{Bulk (Sample)} Is a sampled value of the converter output voltage when the DC-to-DC boost converter is turned on by the control unit. The power supply device of claim 6, wherein the control unit calculates the correction parameter (Slope) according to the following formula, and further calculates an offset parameter (Offset) according to another formula: Offset=V ₁₁ -V ₂₁ * Slope, wherein V ₁₁ and V ₂₁ are at a first time point, the control unit respectively calculates the calculated value (V ₁₁ ) corresponding to the converter output voltage, and the converter The sampled value of the output voltage (V ₂₁ ), V ₁₂ and V ₂₂ are at a second time point, the control unit respectively calculates the calculated value (V ₁₂ ) corresponding to the output voltage of the converter, and outputs the output to the converter The sampled value of the voltage (V ₂₂ ). The power supply device of claim 9, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, V _{Bulk (Result)} = S lope * V _{Bulk (Sample)} + O ffset where V _{Bulk (Sample)} is a sampled value of the converter output voltage when the DC-to-DC boost converter is turned on by the control unit. The power supply device of claim 3, further comprising a resistor and a switching element, the resistor and the switching element being connected in parallel and electrically connected to the DC-to-DC boost converter, wherein the input voltage is The charging path of the capacitor charging further includes the switching element and the resistor, such that V _Trace is that the input voltage charges the capacitor via the switching element and the resistor, the boosting inductor, and the boosting diode The magnitude of the loop drop in the charging path. The power supply device of claim 5, further comprising a resistor and a switching element, the resistor and the switching element being connected in parallel and electrically connected to the DC-to-DC boost converter, wherein the bypass circuit The first end receives the input voltage via the resistor and the switching element, and the charging path for charging the capacitor includes the switching element and the resistor, such that V _Trace is the input voltage via the switching element and the resistor And the bypass circuit, the magnitude of the loop voltage drop of the charging path for charging the capacitor. The power supply device of claim 1 is adapted to receive an AC input voltage, and further comprising a rectifier electrically connected to the DC-to-DC boost converter and receiving the AC input voltage, and the AC input The voltage is converted and the output is the input voltage, and the input voltage is a DC input voltage. The power supply of claim 13, wherein the DC-to-DC boost converter comprises: a boost inductor comprising a first end electrically connected to the rectifier and receiving the input voltage, and a second end a boost diode comprising a first end electrically connected to the second end of the boost inductor, and a second end electrically connected to the first end of the capacitor; and a boost switch comprising Electrically connecting the first end of the second end of the boost inductor and a grounded second end. The power supply of claim 14, wherein the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, V ₁ =V _peak -V _Trace where V _peak is the input voltage The peak value, V _Trace, is the magnitude of the loop voltage drop of the charging path for charging the capacitor via the rectifier, the boost inductor, and the boost diode. The power supply of claim 13, further comprising a bypass circuit including a first end electrically connected to the rectifier and receiving the input voltage, and a second end electrically connected to the first end of the capacitor And set in parallel with the DC-to-DC boost converter. The power supply of claim 16, wherein the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, V ₁ =V _peak -V _Trace where V _peak is the input voltage The peak value, V _Trace, is the magnitude of the loop voltage drop of the charging path through which the input voltage is charged via the rectifier and the bypass circuit. The power supply device of claim 15 or 17, wherein the peak value _{Vpeak of} the input voltage is directly obtained by sampling the input voltage, or the control unit can sample the effective value V _{rms of} the input voltage. After that, indirectly obtained by the following formula The power supply of claim 18, wherein the control unit calculates the correction parameter (Slope) according to the following formula, Where V ₂ is a sampled value of the output voltage of the converter by the control unit. The power supply according to claim 19, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, V _{Bulk (Result)} = S lope * V _{Bulk (Sample),} wherein V _{Bulk (Sample)} Is a sampled value of the converter output voltage when the DC-to-DC boost converter is turned on by the control unit. The power supply of claim 18, wherein the control unit calculates the correction parameter (Slope) according to the following formula, and further calculates an offset parameter (Offset) according to another formula: Offset=V ₁₁ -V ₂₁ * Slope, wherein V ₁₁ and V ₂₁ are at a first time point, the control unit respectively calculates the calculated value (V ₁₁ ) corresponding to the converter output voltage, and the converter The sampled value of the output voltage (V ₂₁ ), V ₁₂ and V ₂₂ are at a second time point, the control unit respectively calculates the calculated value (V ₁₂ ) corresponding to the output voltage of the converter, and outputs the output to the converter The sampled value of the voltage (V ₂₂ ). The power supply device of claim 21, wherein the control unit calculates the correction value V _{Bulk (Result)} according to the following formula, V _{Bulk (Result)} = S lope * V _{Bulk (Sample)} + O ffset where V _{Bulk (Sample)} is a sampled value of the converter output voltage when the DC-to-DC boost converter is turned on by the control unit. The power supply of claim 15 further comprising a resistor and a switching element, the resistor and the switching element being connected in parallel and electrically connected between the rectifier and the DC-to-DC boost converter, wherein The charging path for charging the capacitor to the capacitor further includes the switching element and the resistor, such that V _Trace is the input voltage via the rectifier, the switching element and the resistor, the boost inductor, and the boosting diode Polar body, the magnitude of the loop voltage drop of the charging path that charges the capacitor. The power supply of claim 17, further comprising a resistor and a switching element, the resistor and the switching element being connected in parallel and electrically connected between the rectifier and the DC-to-DC boost converter, wherein The first end of the bypass circuit receives the input voltage via the resistor and the switching element, and the charging path for charging the capacitor includes the switching element and the resistor, such that V _Trace is the AC input voltage via the The magnitude of the circuit voltage drop of the rectifier, the switching element, the resistor, and the bypass circuit, the charging path for charging the capacitor. A voltage correction method for a power supply, the power supply includes a DC-to-DC boost converter, a capacitor, and a DC to DC a buck converter, and a control unit, the DC-to-DC boost converter receives an input voltage and converts the output to a converter output voltage, the capacitor is electrically connected to the DC-to-DC boost converter to receive the converter An output voltage, the DC-to-DC buck converter is electrically connected to the DC-to-DC boost converter and the capacitor to receive the converter output voltage and converted to output as a DC output voltage, and the control unit is electrically connected to the DC-DC converter The boost converter receives the input voltage and the converter output voltage, and the voltage correction method is implemented by the control unit, and includes the following steps: (a) when the DC-to-DC boost converter is turned off, the control unit Sampling the input voltage and the output voltage of the converter respectively; (b) the control unit determines whether the input voltage and the output voltage of the converter are stable, and repeats the step when the input voltage and the output voltage of the converter are not stable. And (c) when the control unit determines that the input voltage and the converter output voltage have stabilized, the control unit is based at least on the input power Calculating a calculated value of the converter output voltage should be, and determining a correction parameter based on the calculated value and the converter output voltage. The voltage correction method according to claim 25, further comprising the step (k) before the step (a) and the step (d) after the step (c): (k) when the DC-to-DC boost converter is turned on The control unit sends a signal to the DC-to-DC boost converter to turn off the DC-to-DC boost converter; and (d) when the DC-to-DC boost converter is turned on, the control unit corrects according to the correction The parameter and the sampled value of the converter output voltage, calculate a school A positive value is passed to the DC-to-DC boost converter to compensate for the output voltage of the DC-to-DC boost converter. The voltage correction method according to claim 26, wherein, in the step (c), the control unit calculates the calculated value V ₁ corresponding to the converter output voltage according to the following formula, V ₁ =V _peak -V _Trace where V _peak is the peak value of the input voltage, and V _Trace is the magnitude of the loop voltage drop of the charging path through which the input voltage is passed through a DC-boost converter of the DC-to-DC boost converter. The voltage correction method of claim 27, wherein in step (c), the peak value V _{peak of} the input voltage may be obtained directly by the control unit by sampling the input voltage, or may be obtained by the control unit by sampling After the effective value of the input voltage V _rms , it is indirectly obtained by the following formula The voltage correction method according to claim 28, wherein in the step (c), the control unit calculates the correction parameter Slope according to the following formula, Where V ₂ is a sampled value of the output voltage of the converter by the control unit. The voltage correction method according to claim 29, wherein in the step (d), the control unit calculates the correction value V _{Bulk (Result} ) according to the following formula, V _{Bulk (Result)} = S lope * V _{Bulk (Sample)} Wherein, V _{Bulk (Sample)} is a sampling value of the output voltage of the converter when the DC-DC boost converter is turned on by the control unit. The voltage correction method of claim 28, wherein the control unit calculates the correction parameter (Slope) according to the following formula, and further calculates an offset parameter (Offset) according to another formula: Offset=V ₁₁ -V ₂₁ * Slope, wherein V ₁₁ and V ₂₁ are at a first time point, the control unit respectively calculates the calculated value (V ₁₁ ) corresponding to the converter output voltage, and the converter The sampled value of the output voltage (V ₂₁ ), V ₁₂ and V ₂₂ are at a second time point, the control unit respectively calculates the calculated value (V ₁₂ ) corresponding to the output voltage of the converter, and outputs the output to the converter The sampled value of the voltage (V ₂₂ ). The voltage correction method according to claim 31, wherein the control unit calculates the correction value V _{Bulk (Result} ) according to the following formula, V _{Bulk (Result)} = S lope * V _{Bulk (Sample)} + O ffset where V _{Bulk (Sample)} is a sampled value of the converter output voltage when the DC-to-DC boost converter is turned on by the control unit. The voltage supply method of claim 30 or 32, the power supply further includes a resistor and a switching element, the resistor and the switching element are connected in parallel, and are electrically connected to the DC-to-DC boost converter, wherein In the step (c), the charging path for charging the capacitor by the input voltage further includes the switching element and the resistor, such that V _Trace is the input voltage via the switching element and the resistor, and the DC-to-DC boost The boost diode of the converter, the magnitude of the loop voltage drop of the charging path that charges the capacitor.