TWI472775B - Dc uninterruptible power system and method for detecting abnormal voltage - Google Patents

Description

DC type uninterruptible power system and voltage abnormality detecting method thereof

The invention relates to a DC type uninterruptible power system, in particular to a voltage anomaly detection method of a DC type uninterruptible power system.

In recent years, with the vigorous development of the information industry, various kinds of hardware devices such as personal computers, communication equipment, and workstations are being widely used in all walks of life. Since information itself is a product with high added value, people do not want to do everything they can to ensure the security of information and the normal operation of computer systems. Therefore, the requirements for power quality are more stringent. Due to the large number of power electronic devices being used, the harmonics generated by them cause factors such as poor power quality and natural disasters, and the utility model cannot guarantee the supply of high-quality stable power. Uninterruptible Power Supply (UPS) It becomes an essential part of the computer or communication system.

The uninterruptible power system (UPS) can avoid data loss and electronic device damage caused by abnormal power supply, and can effectively protect internal components of the electronic device to ensure the service life and accuracy of the electronic device. In addition, when the emergency power is not normal, such as a sudden power failure or power failure, it can also be turned off during the buffer time. At present, the continuous power system on the market is mostly external. That is, the uninterruptible power system is independently disposed outside the host, and is electrically connected to the host by wires. Generally speaking, the uninterruptible power system usually has a discharge mode and a non-discharge mode, and the means for switching the two modes can be used as a mode switch by detecting the power supply status at the output end, so how to accurately and quickly detect Measuring the power supply situation is very important. In use, in order to meet the effect of being able to output a large current at a time, usually the linear regulator needs to maintain an open state, and at the same time, another switching element (such as a gold-oxygen half-effect transistor) is used to avoid DC current recirculation. occur. However, when the UPS is in the non-discharge mode and the linear regulator is still on, the current will be conducted to the output side through the body diode in the MOSFET, except that the voltage comparator cannot detect quickly. The power supply condition on the output side will also cause loss of energy in the non-discharge mode, forcing the battery in the DC type uninterruptible power system to be charged frequently, which greatly reduces the service life of the battery.

The embodiment of the invention provides a DC-type uninterruptible power system, wherein the DC-type uninterruptible power system is electrically connected to the DC power source, and the DC power system is in a non-discharge mode to output a DC voltage as a power supply voltage and supplied to the load, wherein the DC When the power supply is interrupted, the DC uninterruptible power system enters the discharge mode. The DC type uninterruptible power system includes a multiplexer, a battery unit, a linear regulator, a switching transistor, a voltage comparator, and a microcontroller. The multiplexer electrically receives the first control signal, the first reference voltage and the second reference voltage, and outputs the control voltage according to the first control signal, wherein the control voltage is one of the first reference voltage and the second reference voltage. The battery unit is electrically connected to the DC power source through a charging circuit, and the battery unit is configured to output a discharging current in the discharging mode. The linear regulator is electrically connected to the battery unit, the linear regulator receives the battery voltage and connects the multiplexer to receive the control voltage, and selectively outputs the output voltage according to the control voltage, wherein the control voltages of the different voltage values correspond to different voltages The output voltage of the value, and the linear regulator remains on to provide a discharge current from the battery cell to the load in the discharge mode. The switching transistor has a body diode, and the gate of the switching transistor is electrically connected to the multiplexer to receive the second control signal and thereby determine the on or off state, and the gate is electrically connected to the linear regulator to receive The output voltage is electrically connected to the load, wherein the body diode has a turn-on voltage, wherein when the DC-type uninterruptible power system is in the non-discharge mode, the control voltage received by the linear regulator is the first reference The voltage is measured and the switching transistor is brought into an off state, so that the subtraction result of the output voltage and the supply voltage is smaller than the on voltage to turn off the body diode. The voltage comparator is electrically connected to the source of the switch transistor to receive the supply voltage, the voltage comparator is used to detect whether the DC power supply is interrupted, and the voltage comparator receives the third reference voltage and compares the supply voltage with the third reference voltage. The third control signal is output afterwards. The microcontroller is electrically connected between the voltage comparator and the multiplexer, and the microcontroller receives the third control signal and respectively transmits the first and second control signals to the corresponding multiplexer and the switching transistor according to the third control signal a gate to instruct the multiplexer to select one of the first reference voltage and the second reference voltage and to control an on or off state of the switching transistor.

In one embodiment of the present invention, when the DC-type uninterruptible power system is in the discharge mode, the control voltage received by the linear regulator is the second reference voltage and causes the switching transistor to enter a conducting state, thereby making the output voltage equal to the power supply. The predetermined voltage value of the voltage, wherein the non-discharge mode is to supply power from the DC power source to the load, and the discharge mode is to supply power from the battery unit to the load.

In one embodiment of the present invention, when the voltage comparator determines that the DC power source is normally powered, the third control signal is transmitted to the microcontroller to cause the microcontroller to transmit the first and second control signals to the multiplexer and the switch. a crystal, and the multiplexer selects the first reference voltage as a control voltage according to the first control signal and transmits to the linear regulator.

In one embodiment of the present invention, when the voltage comparator determines that the DC power supply is interrupted, the third control signal is transmitted to the microcontroller to cause the microcontroller to transmit the first and second control signals to the multiplexer and the switching transistor. And the multiplexer selects the second reference voltage as the control voltage according to the first control signal and transmits to the linear regulator.

In one embodiment of the invention, the positive input terminal and the negative input terminal of the voltage comparator respectively receive the supply voltage and the first reference voltage, wherein the first reference voltage is less than a predetermined voltage value of the supply voltage.

In one of the embodiments of the present invention, the multiplexer includes a first switch and a second switch. One end of the first switch receives the first reference voltage, and the other end of the first switch is connected to the linear regulator, and the first switch receives the first open signal and determines an on or off state accordingly. One end of the second switch receives the second reference voltage, the other end of the second switch is connected to the linear regulator, and the second switch receives the second open signal and determines an on or off state according to the first switch, wherein the first and second switch signals are The first control signal.

The embodiment of the invention provides a voltage abnormality detecting method, wherein the voltage abnormality detecting method is used for a DC type uninterruptible power system, and the DC type uninterruptible power system is electrically connected to a DC power source, and the DC uninterruptible power system is in a non- In the discharge mode, the DC voltage is output as a supply voltage and supplied to the load. When the DC power supply is interrupted, the DC uninterruptible power system enters the discharge mode. The DC-type uninterruptible power system includes a multiplexer, a battery unit, and a linear regulator. , switching transistor, voltage comparator and microcontroller. The multiplexer electrically receives the first control signal, the first reference voltage and the second reference voltage, and outputs the control voltage according to the first control signal, wherein the control voltage is one of the first reference voltage and the second reference voltage. The battery unit is electrically connected to the DC power source through a charging circuit, and the battery unit is configured to output a discharging current in the discharging mode. The linear regulator is electrically connected to the battery unit, the linear regulator receives the battery voltage and connects the multiplexer to receive the control voltage, and selectively outputs the output voltage according to the control voltage, wherein the control voltages of the different voltage values correspond to different voltages The output voltage of the value, and the linear regulator remains on to provide a discharge current from the battery cell to the load in the discharge mode. The switching transistor has a body diode, and the gate of the switching transistor is electrically connected to the multiplexer to receive the second control signal and thereby determine the on or off state, and the gate is electrically connected to the linear regulator to receive An output voltage, the source of which is electrically connected to the load, wherein the body diode has a turn-on voltage, wherein when the DC-type uninterruptible power system is in the non-discharge mode, the control voltage received by the linear regulator is the first reference voltage and The switching transistor enters an off state, and the result of subtracting the output voltage from the supply voltage is less than the turn-on voltage to turn off the body diode. The voltage comparator is electrically connected to the source of the switch transistor to receive the supply voltage, and the voltage comparator is used to detect the DC power supply Whether the power supply is interrupted and the voltage comparator further receives the third reference voltage and compares the supply voltage with the third reference voltage to output a third control signal. The microcontroller is electrically connected between the voltage comparator and the multiplexer, and the microcontroller receives the third control signal and respectively transmits the first and second control signals to the corresponding multiplexer and the switching transistor according to the third control signal a gate to instruct the multiplexer to select one of the first reference voltage and the second reference voltage and to control an on or off state of the switching transistor. The voltage abnormality detecting method includes the following steps: detecting a power supply voltage; determining whether the DC type uninterruptible power system is in a non-discharge mode; and controlling the linear regulator to receive if the DC type uninterruptible power system is in a non-discharge mode The voltage is the first reference voltage and the switching transistor is brought into an off state, so that the subtraction result of the output voltage and the supply voltage is less than the conduction voltage to turn off the body diode.

In summary, the DC type uninterruptible power system and the voltage abnormality detecting method thereof are provided by the embodiment of the present invention, and the voltage comparator can quickly detect the power supply of the output side of the output side when the linear regulator is turned on. The situation, while reducing the energy loss of the battery unit or other energy storage device in the non-discharge mode, to achieve the effect of normal power supply.

The detailed description of the present invention and the accompanying drawings are to be understood by the claims The scope is subject to any restrictions.

10‧‧‧DC power supply

100, 300‧‧‧DC type uninterruptible power system

110‧‧‧Multiplexer

120‧‧‧Linear regulator

130‧‧‧Voltage comparator

140‧‧‧Microcontroller

150‧‧‧ battery unit

160‧‧‧Voltage detection circuit

170‧‧‧Control unit

CK‧‧‧Charging circuit

CS1‧‧‧First control signal

CS2‧‧‧second control signal

CS3‧‧‧ third control signal

D1‧‧‧ body diode

DS1‧‧‧Charging signal

IOUT‧‧‧Output current

LD‧‧‧ load

M1‧‧‧Switching transistor

RS‧‧‧ voltage detection results

SW1‧‧‧ first switch

SWS1‧‧‧ first switch signal

SW2‧‧‧second switch

SWS2‧‧‧Second switch signal

S510~S540‧‧‧Steps

T11, t21‧‧‧ time

VBUS‧‧‧ supply voltage

VB‧‧‧ battery voltage

VC‧‧‧ control voltage

VD1‧‧‧ turn-on voltage

VDC‧‧‧ DC voltage

VREF1‧‧‧ first reference voltage

VREF2‧‧‧second reference voltage

VREF3‧‧‧ third reference voltage

VOUT‧‧‧ output voltage

1 is a circuit diagram of a DC type uninterruptible power system according to an embodiment of the present invention.

2 is a driving waveform diagram corresponding to the DC type uninterruptible power system of FIG. 1.

3 is a circuit diagram of a DC type uninterruptible power system according to an embodiment of the present invention.

4 is a driving waveform diagram corresponding to the DC type uninterruptible power system of FIG. 3.

FIG. 5 is a flow chart of a method for detecting a voltage anomaly according to an embodiment of the invention.

Various illustrative embodiments are described more fully hereinafter with reference to the accompanying drawings. However, the inventive concept may be embodied in many different forms and should not be construed as being limited to the illustrative embodiments set forth herein. Rather, these exemplary embodiments are provided so that this invention will be in the In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Similar numbers always indicate similar components.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, such elements are not limited by the terms. These terms are used to distinguish one element from another. Thus, a first element discussed below could be termed a second element without departing from the teachings of the inventive concept. As used herein, the term "and/or" includes any of the associated listed items and all combinations of one or more.

[Example of DC type uninterruptible power system]

Please refer to FIG. 1. FIG. 1 is a circuit diagram of a DC-type uninterruptible power system according to an embodiment of the present invention. As shown in FIG. 1 , the DC type uninterruptible power system 100 is electrically connected to the DC power source 10, and the DC power system 100 is in a non-discharge mode to output a DC voltage VDC as a power supply voltage VBUS and supplied to the load LD, wherein the DC power supply is provided. When the power supply is interrupted, the DC uninterruptible power system 100 enters the discharge mode. The DC type uninterruptible power system 100 includes a multiplexer 110, a linear regulator 120, a switching transistor M1, a voltage comparator 130, a microcontroller 140, a battery unit 150, a voltage detecting circuit 160, and a control unit 170. The battery unit 150 is electrically connected to the DC power source 10 through a charging circuit CK. The linear regulator 120 is electrically connected to the multiplexer 110 and is connected to a battery unit 150. The gate of the switching transistor M1 is connected to the microcontroller 140, the drain of the switching transistor M1 is connected to the linear regulator 120, and the source of the switching transistor M1 is connected to the output side of the DC-type uninterruptible power system 100 and a load LD. . The positive input terminal of the voltage comparator 130 is connected to the source of the switching transistor M1, and the negative input terminal of the voltage comparator 130 receives the third reference voltage VREF3. Microcontroller 140 is coupled between multiplexer 110 and voltage comparator 130. The voltage detecting circuit 160 is connected to the output side of the DC type uninterruptible power system 100 to detect the power supply voltage VBUS and accordingly Output voltage detection result RS. The control unit 170 is connected to the voltage detecting circuit 160, and outputs the charging signal DS1 to the charging circuit CK according to the voltage detection result RS.

Regarding the multiplexer 110, the multiplexer 110 receives the first control signal CS1, the first reference voltage VREF1 and the second reference voltage VREF2, and outputs the control voltage VC to the linear regulator 120 according to the first control signal CS1, wherein the control voltage VC It is one of the first reference voltage VREF1 and the second reference voltage VREF2. That is, the multiplexer 110 selects one of the first reference voltage VREF1 and the second reference voltage VREF2 as the control voltage VC of the linear regulator 120 according to the first control signal CS1. Regarding the linear regulator 120, the linear regulator 120 receives the battery voltage VB and receives the control voltage VC, wherein the battery voltage VB is the voltage supplied by the battery unit 150. In this embodiment, the linear regulator 120 is a regulator whose output voltage VOUT is adjustable, that is, the linear regulator 120 selectively outputs or adjusts the magnitude of the output voltage VOUT according to the control voltage VC, and the linear regulator The 120 is maintained in an on state to supply a discharge current IOUT from the battery unit 150 to the load LD in the discharge mode. It is worth mentioning that the linear regulator 120 needs to maintain the on state in both the "discharge mode" and the "non-discharge mode" to meet the effect of immediate large current.

Regarding the switching transistor M1, the switching transistor M1 is connected between the linear regulator 120 and the output side of the DC type uninterruptible power system 100 in order to avoid the DC side current recirculation. The gate of the switching transistor M1 receives the second control signal CS2 transmitted by the microcontroller 140 and determines its own on or off state accordingly. The drain of the switching transistor M1 receives the output voltage VOUT transmitted by the linear regulator 120. The source of the switching transistor M1 outputs a supply voltage VBUS to the load LD. Furthermore, the switching transistor M1 has a body diode D1, the anode of the body diode D1 is connected to the drain of the switching transistor M1, and the cathode of the body diode D1 is connected to the source of the switching transistor M1. The body diode D1 has a turn-on voltage VD1.

Regarding the voltage comparator 130, the positive input terminal and the negative input terminal of the voltage comparator 130 respectively receive the power supply voltage VBUS and the third reference voltage VREF3, and compare the power supply voltage VBUS with the third reference voltage VREF3, and then output the power supply state. The third control signal CS3 is sent to the microcontroller 140. In brief, in the present embodiment, the voltage comparator 130 is configured to detect the power supply voltage VBUS to determine whether the DC power supply 10 has interrupted power supply, wherein the voltage value of the first reference voltage VREF3 is less than a predetermined voltage value of the power supply voltage VBUS, and The designer can further design according to the circuit design requirements or actual application requirements, and is not limited to this embodiment.

Regarding the microcontroller 140, the microcontroller 140 receives the third control signal CS3 containing the power supply status information and transmits the first control signal CS1 and the second control signal CS2 to the corresponding multiplexer 110 and the switch according to the third control signal CS3. The gate of the transistor M1 is used to instruct the multiplexer 110 to select one of the first reference voltage VREF1 and the second reference voltage VREF2 and to control the on or off state of the switching transistor M1.

Regarding the battery unit 150, the battery unit 150 is for outputting the discharge current IOUT to the load LD in the discharge mode. That is, when the voltage comparator 130 determines and determines that the DC power source 10 is interrupted, the DC power system 100 enters the discharge mode and supplies power to the load LD through the battery unit 150.

What is to be taught next is to further explain the working principle of the DC-type uninterruptible power system 100. Before the following description, it should be noted that the power supply circuit includes the DC power source 10 and the DC type uninterruptible power system 100. The DC type uninterruptible power system 100 has a "non-discharge mode" and a "discharge mode", and can switch the DC type by detecting the power supply state on the output side of the power supply circuit (that is, the output side of the DC type uninterruptible power system 100). There are two modes of the uninterruptible power system 100, so how to accurately and quickly detect the power supply state is very important, and in order to meet the effect of providing a large current in real time, the linear regulator 120 needs to maintain the on state.

Please refer to FIG. 1 and FIG. 2 at the same time. FIG. 2 is a driving waveform diagram corresponding to the DC type uninterruptible power system of FIG. 1. In the "non-discharge mode", the DC power source 10 outputs the DC voltage VDC as the power supply voltage VBUS to supply power to the load LD, and when the voltage detecting circuit 160 detects that the DC power source 10 supplies power to the load LD, Accordingly, the voltage detection result RS is transmitted to the control unit 170 to cause the control unit 170 to transmit the charging signal DS1 to the charging circuit CK, thereby causing the DC power source 10 to pass through a charging circuit CK to the battery unit. The charging is performed at 150, and the battery unit 150 also supplies a battery voltage VB to the linear regulator 120. Then, when the voltage comparator 130 compares the power supply voltage VBUS with the third reference voltage VREF3 and judges that the DC power supply 10 is in the normal power supply state, that is, when the power supply voltage VBUS is greater than the third reference voltage VREF3, the voltage is The comparator 130 outputs a third control signal CS3 of a high voltage level to the microcontroller 140, wherein the voltage value of the third reference voltage VREF3 is less than a predetermined voltage value of the supply voltage VBUS. Then, the microcontroller 140 performs a related control mechanism according to the received third control signal CS3 of the high voltage level. Further, the microcontroller 140 outputs the second control signal CS2 of the low voltage level and the low respectively. The first control signal CS1 of the voltage level is connected to the gate of the corresponding switching transistor M1 and the multiplexer 110. Thereafter, the multiplexer 110 selects the first reference voltage VREF1 as the control voltage VC and transmits the control voltage VC to the linear regulator according to the first control signal CS1 of the low voltage level (ie, the digital logic signal “0”). At the same time, the switching transistor M1 enters an off state according to the second control signal CS2 of the low voltage level. Next, the linear regulator 120 outputs an output voltage VOUT according to the received control voltage VC. It is noted that, in this "non-discharge mode", the output voltage VOUT output by the linear regulator 120 causes DC The type uninterruptible power system 100 satisfies the condition that the subtraction result of the output voltage VOUT and the supply voltage VBUS is smaller than the on-voltage VD1, that is, the output voltage VOUT is at least smaller than the sum of the supply voltage VBUS and the on-voltage VD1 to make the body two The pole body D1 is cut off. Accordingly, in the "non-discharge mode", when the linear regulator 120 is maintained in the on state, the output current IOUT (the electric energy supplied from the battery unit 150) does not flow from the current path of the body diode D1 to the direct current type. The output side of the uninterruptible power system 100 can not only effectively detect the voltage of the power supply voltage VBUS on the output side of the power supply circuit, but also reduce the energy loss in the "non-discharge mode" to avoid DC-type uninterrupted power. The battery unit 150 or storage device of system 100 needs to be charged frequently to reduce the useful life of the battery.

Regarding the "discharge mode", at time t11, the voltage comparator 130 compares the supply voltage VBUS with the third reference voltage VREF3 and detects the DC power source 10 When the power supply is turned off, that is, when the supply voltage VBUS is detected to be lower than the third reference voltage VREF3, the voltage comparator 130 shifts the third control signal CS3 of the high voltage level to the low voltage level. The third control signal CS3 is output to the microcontroller 140, wherein the voltage value of the third reference voltage VREF3 is less than a predetermined voltage value of the supply voltage VBUS. Then, the microcontroller 140 performs a related control mechanism according to the received third control signal CS3 of the low voltage level. Further, the microcontroller 140 outputs the second control signal CS2 and the high voltage level respectively. The first control signal CS1 of the voltage level is connected to the gate of the corresponding switching transistor M1 and the multiplexer 110. Thereafter, the multiplexer 110 selects the second reference voltage VREF2 as the control voltage VC and transmits the control voltage VC to the linear regulator according to the first control signal CS1 of the high-level voltage (ie, the digital logic signal "1"). At the same time, the switching transistor M1 enters an on state according to the second control signal CS2 of the high voltage level. Next, the linear regulator 120 outputs an output voltage VOUT according to the received control voltage VC. It is noted that, in this "discharge mode", the output voltage VOUT output by the linear regulator 120 causes the DC type. The uninterruptible power system 100 satisfies the condition that the output voltage VOUT is substantially equal to the predetermined voltage value of the supply voltage VBUS, that is, the output voltage VOUT is at least greater than the supply voltage VBUS such that the source voltage of the switching transistor M1 is greater than zero, wherein In one embodiment, the predetermined voltage value of the supply voltage VBUS is 12 volts. Accordingly, in the "discharge mode", the linear regulator 120 maintains an on state to provide an instantaneous large current, and the output current IOUT flows from the current path of the switching transistor M1 to the output of the DC type uninterruptible power system 100. The side provides a supply voltage VBUS to the load LD, that is, the battery unit 150 provides power to the load LD. Accordingly, the voltage comparator 130 of the present disclosure can quickly detect the power supply condition on the output side of the power supply circuit while the linear regulator 120 is maintained on, and pass the output voltage adjustable linear regulator 120. Therefore, the DC type uninterruptible power system 100 can effectively detect the power supply state of the output side of the power supply circuit in both the "non-discharge mode" and the "discharge mode", and can simultaneously reduce the battery unit 150 or other in the non-discharge mode. The energy loss of the energy storage device to achieve the effect of normal power supply.

In order to explain in more detail the operational flow of the DC-type uninterruptible power system 100 of the present invention, at least one of the following embodiments will be further described.

In the following various embodiments, portions different from the above-described embodiment of Fig. 1 will be described, and the remaining omitted portions are the same as those of the above-described embodiment of Fig. 1. In addition, for the sake of convenience, like reference numerals or numerals indicate similar elements.

[Another embodiment of a DC type uninterruptible power system]

Please refer to FIG. 3. FIG. 3 is a schematic circuit diagram of a DC-type uninterruptible power system according to an embodiment of the present invention. Different from the above-described embodiment of FIG. 3, in the DC-type uninterruptible power system 300 of the present embodiment, the multiplexer 110 includes a first switch SW1 and a second switch SW2. One end of the first switch SW1 receives the first reference voltage VREF1, and the other end of the first switch SW1 is connected to the linear regulator 120 and the first switch SW1 receives the first open signal SWS1 and determines its own on or off state accordingly. One end of the second switch SW2 receives the first reference voltage VREF1, the other end of the second switch SW2 is connected to the linear regulator 120 and the second switch SW2 receives the second open signal SWS2 and determines its own on or off state accordingly. It should be noted that, in this embodiment, the first switch signal SWS1 and the second switch signal SWS2 are both the first control signal CS1 of the embodiment of FIG.

What is to be taught next is to further explain the working principle of the DC-type uninterruptible power system 300.

Please refer to FIG. 3 and FIG. 4 at the same time. FIG. 4 is a driving waveform diagram corresponding to the DC type uninterruptible power system of FIG. In the "non-discharge mode", the DC power source 10 outputs the DC voltage VDC as the power supply voltage VBUS to supply power to the load LD, and when the voltage detecting circuit 160 detects that the DC power source 10 supplies power to the load LD, Therefore, the voltage detection result RS is transmitted to the control unit 170 to cause the control unit 170 to transmit the charging signal DS1 to the charging circuit CK, thereby causing the DC power source 10 to charge the battery unit 150 through a charging circuit CK, and at this time, the battery unit 150 is also A battery voltage VB is supplied to the linear regulator 120. Then, when the voltage comparator 130 compares the supply voltage VBUS with the third reference voltage VREF3 and detects that the DC power supply is in the normal power supply state, the voltage comparator 130 outputs a third control signal CS3 of the high voltage level to Microcontroller 140, wherein the voltage value of the third reference voltage VREF3 is less than a predetermined voltage value of the power supply voltage VBUS. Next, the microcontroller 140 performs a related control mechanism based on the received third control signal CS3 of the high voltage level. Further, the microcontroller 140 outputs a second control signal CS2 of a low voltage level, a first switching signal SWS1 of a high voltage level, and a second switching signal SWS2 of a low voltage level to a corresponding switching transistor M1. The gate, the control end of the first switch SW1 and the control end of the second switch SW2. Thereafter, the switches SW1 and SW2 are respectively turned on and off according to the switching signals SWS1 and SWS2 to pass the first reference voltage VREF1 as the control voltage VC to the linear regulator 120, and at the same time, the switching transistor M1 is based on the low voltage level. The second control signal CS2 enters an off state. Next, the linear regulator 120 outputs an output voltage VOUT according to the received control voltage VC. It is noted that, in this "non-discharge mode", the output voltage VOUT output by the linear regulator 120 causes DC The type uninterruptible power system 300 satisfies the condition that the subtraction result of the output voltage VOUT and the supply voltage VBUS is smaller than the on-voltage VD1, that is, the output voltage VOUT is at least smaller than the sum of the supply voltage VBUS and the on-voltage VD1 to make the body two The pole body D1 is cut off. Accordingly, in the "non-discharge mode", when the linear regulator 120 is maintained in the on state, the output current IOUT does not flow from the current path of the body diode D1 to the output side of the DC type uninterruptible power system 300. Thereby, not only the voltage condition of the power supply voltage VBUS on the output side of the power supply circuit can be effectively detected, but also the energy loss in the "non-discharge mode" can be reduced, so as to avoid the battery unit 150 or the energy storage of the DC type uninterruptible power system 300. The device needs to be charged frequently to reduce the useful life of the battery or energy storage device.

Similarly, regarding the "discharge mode", when the voltage comparator 130 compares the supply voltage VBUS with the third reference voltage VREF3 at time t21 and detects that the DC power supply 10 is interrupted, that is, when the voltage is compared When the device 130 detects that the power supply voltage VBUS is lower than the third reference voltage VREF3, the voltage comparator 130 turns the third control signal CS3 of the high voltage level to the low voltage level and outputs the third control signal CS3 to the micro control. The device 140, wherein the voltage value of the third reference voltage VREF3 is less than a predetermined voltage value of the power supply voltage VBUS. Then, the microcontroller 140 is based on the received low voltage. The third control signal CS3 of the level performs a related control mechanism. Further, the microcontroller 140 respectively outputs the second control signal CS2 of the high voltage level to the gate of the corresponding switching transistor M1 and shifts the first switching signal SWS1 of the high voltage level to the low voltage level. The second switching signal SWS2 of the low voltage level is turned to the high voltage level and transmitted to the control terminals of the first switch SW1 and the second switch SW2, respectively. Thereafter, the switches SW1 and SW2 are respectively turned off and on according to the switching signals SWS1 and SWS2 to pass the second reference voltage VREF2 as the control voltage VC to the linear regulator 120, and at the same time, the switching transistor M1 is according to the high voltage level. The second control signal CS2 enters an on state. Next, the linear regulator 120 outputs an output voltage VOUT according to the received control voltage VC. It is noted that, in this "discharge mode", the output voltage VOUT output by the linear regulator 120 causes the DC type. The uninterruptible power system 300 satisfies the condition that the output voltage VOUT is substantially equal to the predetermined voltage value of the supply voltage VBUS, that is, the output voltage VOUT is at least greater than the supply voltage VBUS such that the source voltage of the switching transistor M1 is greater than zero, wherein In one embodiment, the predetermined voltage value of the supply voltage VBUS is 12 volts. Accordingly, in the "discharge mode", the linear regulator 120 maintains the on state to provide an instantaneous large current, and the output current IOUT flows from the current path of the switching transistor M1 to the output of the DC type uninterruptible power system 300. The side provides a supply voltage VBUS to the load LD, that is, the battery unit 150 provides power to the load LD. Accordingly, the voltage comparator 130 of the present disclosure can quickly detect the power supply condition of the power supply circuit while the linear regulator 120 is maintained on, and pass the output voltage adjustable linear regulator 120 to make the DC type The uninterruptible power system 300 can effectively detect the power supply state of the power supply voltage VBUS in both the "non-discharge mode" and the "discharge mode", and can simultaneously reduce the energy loss of the battery unit 150 or other energy storage device in the non-discharge mode. In order to achieve the effect of normal power supply.

[An embodiment of the voltage abnormality detecting method]

Please refer to FIG. 5. FIG. 5 is a flowchart of a voltage abnormality detecting method according to an embodiment of the present invention. The exemplary step flow described in this embodiment can be implemented by using the DC type uninterruptible power systems 100 and 300 as shown in FIG. 1 or FIG. 3, so please refer to FIG. 1 or FIG. 3 for illustration. And understanding. The voltage abnormality detecting method includes the following steps: detecting a power supply voltage (step S510). It is judged whether or not the DC type uninterruptible power system is in a non-discharge mode (step S520). If the DC type uninterruptible power system is in the non-discharge mode, the control voltage received by the linear regulator is the first reference voltage and the switching transistor is brought into an off state, so that the subtraction result of the output voltage and the supply voltage is less than The voltage is turned on to turn off the body diode (step S530). When the DC-type uninterruptible power system is in a discharge mode, the control voltage received by the linear regulator is the second reference voltage and the switching transistor is brought into an on state, so that the output voltage is equal to the predetermined voltage value of the supply voltage (step S540). The details of each step of the voltage abnormality detecting method of the DC type uninterruptible power system have been described in detail in the above embodiments of FIGS. 1 to 4, and will not be described herein. It should be noted that the steps of the embodiment of FIG. 5 are merely for convenience of description, and the embodiments of the present invention do not use the steps of the steps as a limitation of implementing various embodiments of the present invention.

[Possible effects of the examples]

In summary, the DC type uninterruptible power system and the voltage abnormality detecting method thereof are provided by the embodiment of the present invention, and the voltage comparator can quickly detect the power supply of the output side of the output side when the linear regulator is turned on. The situation, while reducing the energy loss of the battery or other energy storage device in the non-discharge mode, to achieve the effect of normal power supply.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the invention.

10‧‧‧DC power supply

100‧‧‧DC type uninterruptible power system

110‧‧‧Multiplexer

120‧‧‧Linear regulator

130‧‧‧Voltage comparator

140‧‧‧Microcontroller

150‧‧‧ battery unit

160‧‧‧Voltage detection circuit

170‧‧‧Control unit

CK‧‧‧Charging circuit

CS1‧‧‧First control signal

CS2‧‧‧second control signal

CS3‧‧‧ third control signal

D1‧‧‧ body diode

DS1‧‧‧Charging signal

IOUT‧‧‧Output current

LD‧‧‧ load

M1‧‧‧Switching transistor

RS‧‧‧ voltage detection results

VBUS‧‧‧ supply voltage

VB‧‧‧ battery voltage

VC‧‧‧ control voltage

VD1‧‧‧ turn-on voltage

VDC‧‧‧ DC voltage

VREF1‧‧‧ first reference voltage

VREF2‧‧‧second reference voltage

VREF3‧‧‧ third reference voltage

VOUT‧‧‧ output voltage

Claims (10)

A DC-type uninterruptible power system electrically connected to a DC power supply, wherein the DC uninterruptible power system is in a non-discharge mode to output a DC voltage as a supply voltage and supplied to a load, wherein the DC power supply is interrupted when power is supplied The DC uninterruptible power system enters a discharge mode, the DC type uninterruptible power system includes: a multiplexer electrically receiving a first control signal, a first reference voltage and a second reference voltage, and according to the The first control signal outputs a control voltage, wherein the control voltage is one of the first reference voltage and the second reference voltage; a battery unit is electrically connected to the DC power source through a charging circuit, and the battery unit is used for Outputting a discharge current in the discharge mode; a linear regulator electrically connected to the battery unit, the linear regulator receiving the battery voltage and connecting the multiplexer to receive the control voltage, and according to the control voltage Selectively outputting an output voltage, wherein the control voltage of different voltage values corresponds to the output voltage of the different voltage value, and the linear voltage regulator Maintaining an on state to supply the discharge current from the battery unit to the load in the discharge mode; a switching transistor having a body diode, the gate of the switch transistor being electrically connected to the multiplexer for receiving a second control signal and determining an on or off state according to which a gate is electrically connected to the linear regulator to receive the output voltage, and a source is electrically connected to the load, wherein the body diode has a conduction a voltage, and when the DC-type uninterruptible power system is in the non-discharge mode, the control voltage received by the linear regulator is the first reference voltage and causes the switching transistor to enter an off state, thereby causing the output voltage to The voltage reduction result is less than the turn-on voltage to turn off the body diode; a voltage comparator is electrically connected to the source of the switch transistor to receive the power supply voltage, and the voltage comparator is configured to detect whether the DC power source is Interrupt the power supply and The voltage comparator further receives a third reference voltage and compares the supply voltage with the third reference voltage to output a third control signal; and a microcontroller electrically connected to the voltage comparator and the multiplexer The microcontroller receives the third control signal and transmits the first and second control signals to the corresponding gate of the multiplexer and the switch transistor according to the third control signal to indicate The multiplexer selects one of the first reference voltage and the second reference voltage and controls an on or off state of the switching transistor. The DC-type uninterruptible power system of claim 1, wherein when the DC-type uninterruptible power system is in the discharge mode, the control voltage received by the linear regulator is the second reference voltage and And causing the switching transistor to enter an on state, wherein the output voltage is equal to a predetermined voltage value of the supply voltage, wherein the non-discharge mode is to supply power to the load by the DC power source, wherein the discharge mode is to supply power to the battery unit to the load. The DC-type uninterruptible power system of claim 1, wherein when the voltage comparator determines that the DC power source is normally powered, transmitting the third control signal to the microcontroller to enable the microcontroller Transmitting the first and second control signals to the multiplexer and the switch transistor, and the multiplexer selects the first reference voltage as the control voltage according to the first control signal and transmits the voltage to the linear regulator Device. The DC type uninterruptible power system of claim 1, wherein when the voltage comparator determines that the DC power supply is interrupted, the third control signal is transmitted to the microcontroller to enable the microcontroller to transmit Transmitting the first and the second control signals to the multiplexer and the switch transistor, and the multiplexer selects the second reference voltage as the control voltage according to the first control signal and transmits the same to the linear regulator . The DC type uninterruptible power system of claim 1, wherein a positive input terminal and a negative input terminal of the voltage comparator respectively receive the supply voltage and the a first reference voltage, wherein the first reference voltage is less than a predetermined voltage value of the supply voltage. The DC type uninterruptible power system of claim 1, wherein the multiplexer comprises: a first switch, one end of which receives the first reference voltage, and the other end of which is connected to the linear regulator, the first a switch receives a first open signal and determines an on or off state accordingly; and a second switch receives one of the second reference voltages at one end and the linear regulator on the other end, the second switch receiving a first The second open signal and the on or off state is determined accordingly, wherein the first and second switch signals are the first control signal. A voltage abnormality detecting method is used for a continuous current type uninterruptible power system, wherein the DC type uninterruptible power system is electrically connected to a continuous current power source, and the DC uninterruptible power system is in a non-discharge mode to output a DC voltage as a supply voltage is supplied to a load, wherein when the DC power supply is interrupted, the DC uninterruptible power system enters a discharge mode, and the DC type uninterruptible power system includes a multiplexer, a battery unit, and a linear regulator , a switching transistor, a voltage comparator and a microcontroller, the multiplexer electrically receiving a first control signal, a first reference voltage and a second reference voltage, and outputting a first control signal according to the first control signal a control voltage, wherein the control voltage is one of the first reference voltage and the second reference voltage, the battery unit is electrically connected to the DC power source through a charging circuit, and the battery unit is configured to output a discharge in the discharge mode Current, the linear regulator is electrically connected to the battery unit, the linear regulator receives the battery voltage and is connected to the multiplexer to receive the control voltage, and Selecting an output voltage according to the control voltage, wherein the control voltage of the different voltage value corresponds to the output voltage of the different voltage value, and the linear regulator maintains an on state to be from the battery unit in the discharge mode Providing the discharge current to the load, the switch transistor has a body diode, and the gate of the switch transistor is electrically connected to the multiplexer to connect Receiving a second control signal and determining an on or off state according to which the anode is electrically connected to the linear regulator to receive the output voltage, and the source is electrically connected to the load, wherein the body diode has a Turning on a voltage, and when the DC-type uninterruptible power system is in the non-discharge mode, the control voltage received by the linear regulator is the first reference voltage and causes the switching transistor to enter an off state, thereby causing the output voltage to The voltage reduction result is less than the turn-on voltage to turn off the body diode, and the voltage comparator is electrically connected to the source of the switch transistor to receive the supply voltage, and the voltage comparator is configured to detect the Whether the DC power supply interrupts the power supply and the voltage comparator further receives a third reference voltage and compares the power supply voltage with the third reference voltage to output a third control signal, and the microcontroller is electrically connected to the voltage comparator And the multiplexer receives the third control signal and respectively transmits the first and second control signals according to the third control signal to The multiplexer and the gate of the switch transistor are configured to instruct the multiplexer to select one of the first reference voltage and the second reference voltage and control an on or off state of the switch transistor, The voltage abnormality detecting method includes: detecting the power supply voltage; determining whether the DC type uninterruptible power system is in a non-discharge mode; and if the DC type uninterruptible power system is in the non-discharge mode, causing the linear regulator The control voltage received is the first reference voltage and the switching transistor is brought into an off state, so that the subtraction result of the output voltage and the supply voltage is less than the turn-on voltage to turn off the body diode. The voltage abnormality detecting method according to claim 7, wherein when the DC type uninterruptible power system is in the discharging mode, the control voltage received by the linear regulator is the second reference voltage and The switching transistor enters an on state, and the output voltage is equal to a predetermined voltage value of the supply voltage, wherein the non-discharge mode is to supply power to the load by the DC power source, wherein the discharge mode is to supply power to the load by the battery unit . The voltage abnormality detecting method according to claim 7, wherein when the voltage comparator determines that the DC power source is normally powered, transmitting the third control signal to the microcontroller to enable the microcontroller to transmit Transmitting the first and the second control signals to the multiplexer and the switch transistor, and the multiplexer selects the first reference voltage as the control voltage according to the first control signal and transmits the same to the linear regulator . The voltage abnormality detecting method of claim 7, wherein when the voltage comparator determines that the DC power supply is interrupted, the third control signal is transmitted to the microcontroller to enable the microcontroller to transmit the The first and the second control signals are sent to the multiplexer and the switch transistor, and the multiplexer selects the second reference voltage as the control voltage according to the first control signal and transmits the voltage to the linear regulator.