Power supply device and method of operation of the power supply decice

Abstract

A power supply device according to the present invention comprises: a rectifier unit that rectifies an alternating current input via a circuit breaker; a smoothing unit that includes at least one smoothing capacitor and smooths an electrical signal rectified by the rectifier unit; a detection unit that detects whether power supply to the power supply device is interrupted through a voltage change of the smoothing capacitor that drops when power supply to the power supply device is interrupted, and outputs a power supply interruption signal according to the detection result; a communication unit that receives the power supply interruption signal and transmits a notification signal pre-set in an upper system; and a DC-DC converter that receives the current smoothed by the smoothing unit and supplies operating power for driving the detection unit and the communication unit, wherein the DC-DC converter is connected to the smoothing capacitor and receives the current discharged from the smoothing capacitor when power supply to the power supply device is interrupted, and supplies operating power for driving the detection unit and the communication unit.

Description

Technology Field

[0001] The present invention relates to a power supply device that supplies power to a load. Background Technology

[0002] With energy efficiency becoming increasingly important due to recent low-carbon policies, the importance of power supply management through distribution panels is on the rise. In particular, load-specific power management using circuit breakers within distribution panels is essential in smart factories, smart buildings, or similar ICT (Information Communication Technology) environments.

[0003] In load-based power management at the distribution panel level, it is crucial to monitor not only the power of individual loads but also the ON (power supply) and OFF (power cutoff) status of circuit breakers. For example, in the case of a circuit breaker connected to a medicine storage refrigerator in a hospital, the refrigerator may stop operating if the breaker is switched off due to unexpected circumstances. In such cases, the medicines stored inside may deteriorate or be damaged. Since the location must be quickly identified and corrective action taken when a circuit breaker unexpectedly switches off in an IDC environment, the importance of managing circuit breaker status information is increasing. Consequently, distribution panels, particularly smart distribution panels, are required to have the capability to detect the ON and OFF status of these circuit breakers in real time. Furthermore, to detect whether a circuit breaker is ON or OFF, a method is required that enables the distribution panel to detect in real time whether power is being supplied to each load.

[0004] In response to these demands, a method has emerged to monitor whether power is being supplied to each load using a separate detector. In this case, the detector detects whether power is being supplied from the circuit breaker to the load and notifies a higher-level system (e.g., a smart distribution panel) whether the power supply has been interrupted based on the detection result, thereby enabling the smart distribution panel to identify the on / off status of the circuit breaker connected to the load.

[0005] However, power supply is required to operate such detectors, and in this case, the power supplied to the load must be utilized. This presents a problem: if the power supplied to the load is cut off by a circuit breaker, the detector also loses power supply and turns off along with the load. Since the detector turns off in this situation, the upper system must periodically check the detection signal received from the detector and identify that the circuit breaker is in the off state when no signal is received.

[0006] Furthermore, considering communication anomalies (e.g., collisions), when the upper system determines the off state of the circuit breaker when a periodic detection signal is not received more than a preset number of times, there is a problem in that, under normal circumstances, when the circuit breaker is turned off, the detection of the circuit breaker off state may be delayed for a period of time corresponding to several times the frequency at which the detection signal is transmitted. The problem to be solved

[0007] The present invention aims to solve the aforementioned problems and other problems, and aims to provide a power supply device capable of detecting whether power supply to a load is interrupted and notifying an upper system when power supply to the load is interrupted, and a method of operation of the power supply device.

[0008] Furthermore, the present invention aims to provide a power supply device and a method of operation of the power supply device, which can check whether power supplied to a load has been interrupted on a load-by-load basis using the configuration of an existing power supply device, and, in the event that power supplied to a load is interrupted, can perform a communication connection with said upper system for a period longer than a preset time during which the interruption of power supply can be notified to said upper system. means of solving the problem

[0009] According to one aspect of the present invention for achieving the above or other purposes, a power supply device according to an embodiment of the present invention comprises: a rectifier unit that rectifies an alternating current input via a circuit breaker; a smoothing unit that includes at least one smoothing capacitor and smooths an electrical signal rectified by the rectifier unit; a detection unit that detects whether power supply to the power supply device is interrupted through a voltage change of the smoothing capacitor that drops when power supply to the power supply device is interrupted, and outputs a power supply interruption signal according to the detection result; a communication unit that receives the power supply interruption signal and transmits a notification signal pre-set in an upper system; and a DC-DC converter that receives the current smoothed by the smoothing unit and supplies operating power for driving the detection unit and the communication unit, wherein the DC-DC converter is connected to the smoothing capacitor and receives the current discharged from the smoothing capacitor when power supply to the power supply device is interrupted, and supplies operating power for driving the detection unit and the communication unit.

[0010] In one embodiment, the smoothing capacitor is characterized by having a capacitance determined according to a minimum required driving time determined by the time during which the communication unit can transmit the notification signal to the upper system a preset number of times after the power supply to the power supply unit is interrupted.

[0011] In one embodiment, the detection unit is characterized by detecting that the power supply of the power supply device has been interrupted when the voltage level detected from the smoothing capacitor drops by a preset voltage level based on the voltage peak value of the smoothing capacitor.

[0012] In one embodiment, the preset voltage level is characterized by being determined according to the magnitude of the ripple voltage determined from the smoothed electrical signal.

[0013] In one embodiment, the detection unit is characterized by turning off itself by cutting off the input power when the power supply interruption signal is output to the communication unit.

[0014] In one embodiment, the DC-DC converter is characterized by supplying an operating power supply for driving at least one of the detection unit and the communication unit from the time when the voltage level detected from the smoothing capacitor drops by the preset voltage level until the time when all the charge charged in the smoothing capacitor is discharged.

[0015] In one embodiment, the detection unit is characterized by detecting the voltage level of the smoothing capacitor again a predetermined number of times at a predetermined time interval when the voltage level detected from the smoothing capacitor drops to a preset voltage level, and outputting the power supply interruption signal to the communication unit when the voltage of the smoothing capacitor detected again a predetermined number of times is less than or equal to the preset voltage level.

[0016] In one embodiment, the smoothing capacitor is configured by connecting a plurality of capacitors in parallel, and the DC-DC converter is connected to any one of the plurality of parallel-connected capacitors and is characterized by converting power supplied from the connected capacitor and supplying it as operating power for driving the detection unit and the communication unit.

[0017] In one embodiment, between the smoothing unit and the DC-DC converter, an auxiliary capacitor is further provided that is charged by receiving the smoothed current from the smoothing unit and discharges the power charged in the DC-DC converter, and the DC-DC converter is characterized by receiving the current discharged from the auxiliary capacitor when power supply to the power supply unit is interrupted and supplying operating power for driving the detection unit and the communication unit.

[0018] In one embodiment, the auxiliary capacitor is characterized by having a capacity determined according to a minimum required driving time determined by the time during which the communication unit can transmit the notification signal to the upper system a preset number of times after the power supply to the power supply unit is interrupted.

[0019] According to one aspect of the present invention for achieving the above or other purposes, a method of operation of a power supply device according to an embodiment of the present invention comprises: a step in which a rectifier unit rectifies an alternating current input to the power supply device via a circuit breaker; a step in which a smoothing unit including at least one smoothing capacitor smooths the rectified electrical signal; a step in which a DC-DC converter converts the smoothed electrical signal into a direct current having a preset voltage and supplies it as an operating power source for a detection unit and a communication unit of the power supply device; a step in which, when power supply to the power supply device is interrupted, the DC-DC converter converts electrical energy discharged from the smoothing capacitor and supplies it as an operating power source for the detection unit and the communication unit; a step in which, after power supply to the power supply device is interrupted, a detection unit driven by electrical energy discharged from the smoothing capacitor detects the voltage level of the smoothing capacitor to detect whether power supply to the power supply device is interrupted and outputs a voltage off signal to the communication unit; and a step in which, after power supply to the power supply device is interrupted, a detection unit driven by electrical energy discharged from the smoothing capacitor The communication unit is characterized by including the step of receiving the voltage off signal and transmitting a preset notification signal to an upper system.

[0020] In one embodiment, the step of the detection unit outputting the voltage off signal to the communication unit further includes the step of the detection unit turning off itself by cutting off the current supplied from the DC-DC converter to the detection unit after outputting the voltage off signal.

[0021] In one embodiment, the step of the communication unit transmitting the notification signal to the upper system is characterized by the step of transmitting the notification signal repeatedly a preset number of times during the time from when the detection unit detects the interruption of power supply to the power supply unit according to the voltage level of the smoothing capacitor until when all the charge charged in the smoothing capacitor is discharged. Effects of the invention

[0022] According to at least one embodiment of the present invention, the present invention has the effect of detecting a change in the operating state of the circuit breaker without a separate detector by detecting whether the power supply is interrupted through a power supply device that individually supplies power to a load, and enabling an upper system to identify the detected operating state of the circuit breaker.

[0023] In addition, the present invention has the effect of enabling the upper system to clearly identify changes in the operating state of the circuit breaker by maintaining a communication connection with the upper system for a preset time when the power supplied to the load is interrupted, thereby transmitting to the upper system that the power supply to the load has been interrupted.

[0024] In addition, the present invention has the effect of enabling a notification signal indicating that the power supply to the load has been interrupted to be transmitted to the upper system without additional components such as an auxiliary battery, by providing power that allows the power supply to operate for a preset time during which a communication connection with the upper system is maintained when the power supplied to the load is interrupted, using the configuration of a conventional power supply. Brief explanation of the drawing

[0025] FIG. 1 is a configuration diagram illustrating the configuration of a power supply device according to an embodiment of the present invention. FIG. 2 is a conceptual diagram illustrating the current flow when current is supplied normally to a power supply device according to an embodiment of the present invention. FIG. 3 is an exemplary diagram illustrating an example of a full-wave rectified voltage waveform and a rectified smoothed voltage waveform in a power supply according to an embodiment of the present invention. Figure 4 is an example diagram showing the voltage change of an electrical signal output from a smoothing unit when power supply to a power supply is interrupted. FIGS. 5 and 6 are conceptual diagrams illustrating the current flow when the current supply to the power supply is interrupted in a power supply according to an embodiment of the present invention. FIG. 7 is a graph showing the time during which the communication unit (170) can be operated when the power supply to the power supply device according to an embodiment of the present invention is interrupted. FIG. 8 is a configuration diagram illustrating the configuration of another power supply device according to an embodiment of the present invention. FIGS. 9 to 11 are conceptual diagrams illustrating the current flow when power supply to a power supply device (20) is interrupted according to another embodiment of the present invention. FIG. 12 is a flowchart showing the operation process of a power supply device according to an embodiment of the present invention. Specific details for implementing the invention

[0026] It should be noted that technical terms used in this specification are used merely to describe specific embodiments and are not intended to limit the invention. Additionally, singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "composed of" or "comprising" should not be interpreted as necessarily including all of the various components or steps described in the specification, and should be interpreted as meaning that some of the components or steps may be omitted, or that additional components or steps may be included.

[0027] In addition, when describing the technology disclosed in this specification, if it is determined that a detailed description of related prior art could obscure the essence of the technology disclosed in this specification, such detailed description is omitted.

[0028] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings.

[0029] Typically, a power supply refers to a device that receives current as input and converts it into the power required by a load, such as voltage, current, or frequency, of a preset magnitude. Accordingly, a power supply may include an AC / DC converter when the input power is AC, and a DC / DC converter when the input power is DC.

[0030] Meanwhile, since alternating current is typically used for long-distance power transmission to reduce resistance losses, a general power supply unit converts the supplied alternating current into direct current and can convert the converted direct current according to the voltage required by the load. Accordingly, the power supply unit may include both an AC-DC converter and a DC-DC converter.

[0031] FIG. 1 is a configuration diagram illustrating the configuration of a power supply device (10) according to an embodiment of the present invention.

[0032] Referring to FIG. 1, a power supply device (10) according to an embodiment of the present invention may be configured to include an AC input unit (100) through which an alternating current is input via a circuit breaker, a rectifier unit (110) that rectifies the alternating current input from the AC input unit (100) in full-wave rectification, a smoothing unit (120) that smooths the electrical signal rectified in full-wave rectifier unit, and a DC-DC converter (160) that converts the electrical signal whose voltage has been smoothed in the smoothing unit (120) into a DC current of a preset voltage. In this case, the rectifier unit (110) and the smoothing unit (120) may be configured as AC-DC converters. That is, the power supply device (10) can convert the input alternating current into a DC current (AC-DC converter (110, 120)), and convert the converted DC current back into a DC current of a preset voltage.

[0033] In addition, a power supply device (10) according to an embodiment of the present invention may be configured to include a voltage reduction unit (130) that reduces the DC current converted by the AC-DC converter to a DC current having a voltage of a preset size, a detection unit (140) that detects the voltage level of the DC current converted by the voltage reduction unit (130) and detects whether the power supply to the power supply device (10) has been interrupted based on the detected voltage level, and a communication unit (170) that operates based on a detection signal input from the detection unit (140) and transmits a notification signal to a preset upper system, such as a smart distribution board (not shown), indicating that the power supply to the load has been interrupted according to the detection signal.

[0034] In this case, the detection unit (140) and the communication unit (170) may each be configured as separate MCUs (Micro Controller Units). In this case, the detection unit (140) and the communication unit (170) may each be individually turned on or off.

[0035] The AC input unit (100) may receive current supplied from a smart distribution board. Additionally, a circuit breaker (not shown) may be placed between the AC input unit (100) and the smart distribution board. Accordingly, when the circuit breaker is turned off, the AC input unit (100) is electrically cut off, and the power supply to the AC input unit (100) may be interrupted.

[0036] The above rectifier (110) may be configured to include a diode bridge or a bridge rectifier that constitutes a bridge circuit. The above rectifier (110) is a full-wave rectifier circuit that converts and rectifies the negative voltage of the input voltage into a positive voltage, and can convert the input AC current into a pulsating current. The smoothing unit (120) is equipped with a Zener diode and a smoothing capacitor (121) to convert the input pulsating current into a voltage of a constant magnitude by smoothing the voltage change. Accordingly, the pulsating current can be converted into a DC current. That is, the above rectifier (110) and the above smoothing unit (120) are connected to form an AC-DC converter that converts AC current into DC current. In this case, a DC current (first-order converted current) having a voltage similar to the voltage of the input AC current can be generated.

[0037] The smoothing unit (120) above may be connected to at least one DC-DC converter. Here, the DC-DC converter (not shown) connected to the load receives the primary conversion current and converts it into a DC current of a specific voltage. The DC current of a specific voltage converted by the DC-DC converter can be supplied as a power source for driving the load.

[0038] Meanwhile, as described above, the power supply device (10) according to the embodiment of the present invention may be equipped with a detection unit (140) that detects whether there is a current supplied to a load depending on whether there is a current supplied through the AC input unit (100), and a communication unit (170) that transmits a notification signal to an upper system to notify when the supply of current to the load is interrupted.

[0039] In this case, any one DC-DC converter (160) connected to the smoothing unit (120) can convert the input primary conversion current into a direct current having a preset voltage, and supply the converted direct current (secondary conversion current) as a driving power source for driving the detection unit (140) and the communication unit (170). That is, from the alternating current supplied to the load, the detection unit (140) for detecting whether the circuit breaker is off in the power supply unit (10) and the communication unit (170) for transmitting a notification signal to indicate the circuit breaker off state can be driven. FIG. 1 illustrates an example in which the preset voltage is 3.3V.

[0040] Meanwhile, the detection unit (140) can receive the current output from the smoothing unit (120) via the voltage reduction unit (130). More specifically, as shown in FIG. 1, the detection unit (140) is connected to the smoothing capacitor (121) of the smoothing unit (120) and can receive the voltage output from the smoothing capacitor (121). In this case, the smoothing capacitor (121) smooths the pulsating current rectified in the rectifier unit (110), and the detection unit (140) can detect the voltage level of the first-order converted (first-order rectified) signal that converts the alternating current into a direct current in the AC-DC converter.

[0041] In this case, since the primary rectified signal from the AC-DC converter is a high voltage of approximately 50V, the voltage detected by the smoothing capacitor (121) can be reduced to a voltage within a preset voltage range (e.g., 3.3V or less) through the voltage reduction unit (130). For this voltage reduction, the voltage reduction unit (130) may be equipped with a voltage divider circuit (131) including a plurality of resistors, and the level of the voltage reduced to a voltage within a preset range by being divided through the voltage divider circuit (131) can be detected by the detection unit (140).

[0042] The detection unit (140) can detect whether power supply to the power supply unit (10) has been interrupted depending on whether the detected voltage level is below a preset threshold level. Here, the threshold level can be determined between 70% and 80% of a preset reference voltage. And if the detected voltage level is below the threshold level, the detection unit (140) can transmit a voltage off signal to the communication unit (170).

[0043] Meanwhile, the communication unit (170) can transmit a pre-set notification signal to the upper system according to the voltage off signal received from the detection unit (140). The notification signal may be a signal indicating that the power supply to the power supply unit (10) has been interrupted. The notification signal may be transmitted in the form of a wireless signal, and to this end, the communication unit (170) may be equipped with a wireless signal transmission and reception module (not shown) for exchanging wireless signals with the upper system.

[0044] Meanwhile, the above DC-DC converter (160) can be connected to the smoothing capacitor (121) of the smoothing unit (120) as shown in FIG. 1. Accordingly, the output voltage of the smoothing capacitor (121) can be supplied to the DC-DC converter (160).

[0045] In this case, the smoothing capacitor (121) can be charged when the current supply from the rectifier (110) continues, and the charged charge can be discharged when the current supply from the rectifier (110) is interrupted. Accordingly, when the current supply from the rectifier (110) is interrupted, that is, when the current supply to the power supply device (10) is cut off due to the off operation of the circuit breaker, the charge charged in the smoothing capacitor (121) can be discharged, and the current corresponding to the charge discharged in the smoothing capacitor (121) can be supplied to the DC-DC converter (160).

[0046] Therefore, even when the circuit breaker is turned off and the current supply to the power supply unit (10) is cut off, the DC-DC converter (160) can be maintained in operation until all the charge charged in the smoothing capacitor (121) is discharged, and the secondary conversion current converted in the DC-DC converter (160) can be supplied to the detection unit (140) and the communication unit (170). Therefore, even when the current supply to the power supply unit (10) is cut off, the detection unit (140) and the communication unit (170) can be supplied with power for operation for a certain period of time.

[0047] Accordingly, the communication unit (170) can secure time to transmit a notification signal to the upper system indicating that the power supply has been cut off, even when the current supply to the power supply unit (10) is cut off. The upper system can identify that the power supply to the power supply unit (10) has been cut off and identify the operating state (off state) of the circuit breaker connected to the power supply unit (10).

[0048] Here, the detection unit (140) can be turned off when the voltage off signal is transmitted to the communication unit (170). Then, the current supply to the detection unit (140) is interrupted, reducing the power consumption of the smoothing capacitor (121), and the operating time (additional operating time) during which the communication unit (170) can be operated after the current supply to the power supply unit (10) is interrupted can be increased.

[0049] In this way, the smoothing capacitor (121) of the power supply unit (10) according to the embodiment of the present invention provides power that allows the communication unit (170) to be additionally driven when the current supply to the power supply unit (10) is cut off. And during the additional driving time, the communication unit (170) transmits a notification signal (current supply interruption notification signal) according to the voltage off signal to the upper system, thereby enabling the upper system to identify the interruption of the power supply of the power supply unit (10).

[0050] Meanwhile, considering cases where communication failures may occur, the communication unit (170) may transmit the notification signal to the upper system more than a preset number of times. In this case, the communication unit (170) may transmit the notification signal to the upper system and, if an acknowledgment signal (ACK) is not received from the upper system for a certain period of time, transmit the notification signal again. Accordingly, while the current supply to the power supply unit (10) is interrupted, additional operating time may be required for the communication unit (170) to operate additionally for a minimum time during which the notification signal can be transmitted a preset number of times.

[0051] In this case, as described above, when the current supply to the power supply unit (10) is cut off, the power supplied to the detection unit (140) and the communication unit (170) is supplied from the smoothing capacitor (121), and the additional driving time of the communication unit (170) can be determined according to the amount of charge charged in the smoothing capacitor (121), that is, the capacity of the smoothing capacitor. That is, in the power supply unit (10) according to the embodiment of the present invention, the smoothing capacitor (121) of the smoothing unit (120) constituting the AC-DC converter can be designed with a sufficient capacity to secure the additional driving time required by the communication unit (170). For example, the smoothing capacitor (121) may have a capacity of 2μF to 10μF, and the larger the capacity of the smoothing capacitor (121), the longer the additional driving time of the communication unit (170) can be secured.

[0052] Meanwhile, the DC-DC converter (160) may be equipped with an additional capacitor (161) at the output terminal. In this case, the additional capacitor (161) can charge the output charge when current is output from the DC-DC converter (160) and discharge the charged charge when current is not output from the DC-DC converter (160). Accordingly, when the additional capacitor (161) is provided, the power consumed by the smoothing capacitor (121) is reduced, thereby securing additional operating time for the communication unit (170).

[0053] FIG. 2 is a conceptual diagram illustrating the current flow when current is normally supplied to the power supply device (10) according to the embodiment of the present invention as described in FIG. 1. FIG. 3 is an exemplary diagram illustrating an example of a full-wave rectified voltage waveform and a rectified smoothed voltage waveform in the power supply device according to the embodiment of the present invention.

[0054] First, referring to FIG. 2, when current is supplied normally, that is, when the circuit breaker is in the ON state, the AC input unit (100) can receive the alternating current supplied normally through the smart distribution board. Then, the input alternating current can be rectified through the rectifier unit (110) and converted into a pulsating current signal having only the positive voltage component, as shown in FIG. 3 (a).

[0055] Meanwhile, the current (200) converted into a pulsating signal in this manner can be input to the smoothing unit (120). The voltage can be smoothed through the charging and discharging process of the Zener diode and the smoothing capacitor (121) provided in the smoothing unit (120). In this case, the smoothed electrical signal may have an AC signal component that remains un-DC, i.e., a ripple voltage (300), as shown in Fig. 3 (b). Since this ripple voltage is determined by the capacitor and load of the smoothing circuit, the larger the capacitance of the smoothing capacitor (121) of the smoothing unit (120), the more the ripple voltage can be reduced.

[0056] Meanwhile, the above ripple voltage is a voltage generated by charging and discharging in the smoothing capacitor (121), and the above ripple voltage may be the voltage of the smoothing capacitor (121). In this case, the detection unit (140) of the power supply device (10) according to the embodiment of the present invention is connected to the smoothing capacitor (121) as shown in FIG. 1, so the voltage level of the smoothing capacitor (121) can be detected through the output current (210) of the smoothing capacitor (121) as shown in FIG. 2.

[0057] Here, the voltage of the smoothing capacitor (121) is the voltage of the current converted into DC without voltage conversion from the alternating current input to the AC input unit (100), and may be a high voltage that could damage the circuit of the detection unit (140) if directly input to the detection unit (140). Accordingly, the power supply device (10) according to an embodiment of the present invention is provided with a voltage reduction unit (130) between the smoothing capacitor (121) and the detection unit (140) so that the voltage of the smoothing capacitor (121) can be converted into a voltage signal within an identifiable range by the detection unit (140).

[0058] In this case, the voltage reduction unit (130) may include a voltage divider circuit comprising a plurality of resistors as shown in FIGS. 1 and 2, and by dividing the voltage (210) of the smoothing capacitor (121) by a constant magnitude through the voltage divider circuit, the voltage of the smoothing capacitor (121) can be converted into a voltage signal within an identifiable range by the detection unit (140).

[0059] For example, if the voltage input through the AC input unit (100) is around 100V, the voltage of the smoothing capacitor (121) may be around 50V, which is about half the voltage of the input signal. Then, the voltage reduction unit (130) can convert the voltage signal around 50V into a voltage signal of 3.3V or less, which is within a range identifiable by the detection unit (140), through a voltage divider circuit. Then, the voltage signal of the 3.3V or less range reduced by the voltage reduction unit (130) can be input to the detection unit (140), and the voltage level can be detected through the detection unit (140).

[0060] Meanwhile, as shown in FIG. 2 above, the smoothing unit (120) can be connected to the DC-DC converter (160). Accordingly, the smoothing capacitor (121) of the smoothing unit (120) can be connected to the DC-DC converter (160).

[0061] Through this connection, the DC-DC converter (160) can receive an electrical signal (220) in which the voltage has been smoothed in the smoothing unit (120). The input electrical signal (220) can be converted into an electrical signal having a preset voltage, for example, 3.3V. The converted electrical signal having the preset voltage can be input as an operating power source (141, 171) for driving the detection unit (140) and the communication unit (170).

[0062] Here, the DC-DC converter (160) may be a DC-DC converter different from the DC-DC converter (not shown) that supplies power to the load. That is, the DC-DC converter (160) may be a power conversion unit for supplying operating power to the detection unit (140) and communication unit (170) provided in the power supply unit (10), and may be a DC-DC converter (160) connected to the smoothing capacitor (121) of the smoothing unit (120), separate from the DC-DC converter that supplies the electrical signal supplied to the load. In this case, the DC-DC converter that supplies power to the load may be a converter that converts the electrical signal to a different voltage than the DC-DC converter (160), for example, 3.3V.

[0063] That is, the present invention may separately provide a DC-DC converter (160) for supplying operating power to a detection unit (140) that detects the voltage level of a smoothing capacitor (121) and a communication unit (170) that transmits a notification signal indicating that the power supply has been interrupted according to the detection result of the detection unit (140). In addition, the DC-DC converter (160) may be connected to the smoothing capacitor (121) of the smoothing unit (120) separately from another DC-DC converter that supplies power to the load.

[0064] Meanwhile, FIG. 4 is an example diagram showing the voltage change of an electrical signal output from a smoothing unit (120) when power supply to a power supply unit (10) is interrupted. FIG. 5 and FIG. 6 are conceptual diagrams illustrating the current flow when power supply to a power supply unit is interrupted, as seen in FIG. 4, in the power supply unit (10) according to the embodiment of the present invention described above.

[0065] First, referring to FIG. 4, FIG. 4 illustrates an example in which power supply to the power supply unit (10) is cut off due to the operation (off state) of the blocking unit. In this case, as the AC current input to the rectifier unit (110) is interrupted, the electrical signal output (200) from the rectifier unit (110) and the smoothing unit (120) may be interrupted.

[0066] In this case, as described above, the smoothing unit (120) is equipped with a smoothing capacitor (121) to reduce the ripple voltage through charging and discharging. However, when the input of the pulsating current signal to the smoothing unit (120) is interrupted, the smoothing capacitor (121) is no longer charged, and only the charge charged in the smoothing capacitor (121) can be discharged. Therefore, as shown in FIG. 4, the voltage of the primary rectified electrical signal output from the smoothing unit (120) can be reduced from the point of current supply interruption (401) until the point of discharge (402, the point where the voltage becomes 0) when all the charge charged in the smoothing capacitor (121) is discharged.

[0067] Meanwhile, the detection unit (140) is connected to the smoothing capacitor (121) and can detect the voltage level of the electrical signal output from the smoothing capacitor (121). Thus, as shown in FIG. 4, when the power supply to the power supply unit (10) is cut off, the voltage of the smoothing capacitor (121) detected by the detection unit (140) can be lowered. And when the lowered voltage of the smoothing capacitor (121) reaches a preset reference voltage level (410), it can be determined that the power supply to the power supply unit (10) has been interrupted. Thus, it can be detected that the power supply to the power supply unit (10) has been interrupted before all the charge charged in the smoothing capacitor (121) is discharged.

[0068] Here, the voltage of the smoothing capacitor (121) is a voltage that is charged and discharged to smooth the pulsating signal, and the voltage change of the smoothing capacitor (121) may be equal to the magnitude of the ripple voltage. Accordingly, the detection unit (140) can detect the magnitude of the ripple voltage based on the voltage change of the smoothing capacitor (121).

[0069] In this case, if power is supplied normally to the power supply unit (10), an electrical signal is input before the smoothing capacitor (121) is discharged below a certain level, and thus the smoothing capacitor (121) is charged, so the magnitude of the ripple voltage may be less than a preset magnitude. However, as described above, if power is supplied to the power supply unit (10) is interrupted, there is no input electrical signal, so the charge of the smoothing capacitor (121) may be continuously discharged as shown in FIG. 4.

[0070] Accordingly, the voltage level may drop from the voltage peak point by exceeding the preset magnitude of the ripple voltage. Accordingly, the detection unit (140) may determine that the power supply to the power supply device (10) has been interrupted when the voltage level of the smoothing capacitor (121) drops by more than the preset magnitude of the ripple voltage from the voltage peak point.

[0071] And when a power supply interruption to the power supply device (10) is detected, the detection unit (140) can transmit a power off signal (500) to the communication unit (170), as shown in FIG. 5. In this case, that is, at the time (403) when the power supply interruption is detected because the power supply is interrupted, there may be a state in which the charge charged in the smoothing capacitor (121) remains and the charge charged in the smoothing capacitor (121) is discharged to the DC-DC converter (160).

[0072] That is, the DC-DC converter (160) can be formed to receive the current (220) discharged from the smoothing capacitor (121) even when the power supply to the power supply unit (10) is interrupted, and by converting the current (220) discharged from the smoothing capacitor (121) into a DC current having a preset voltage and outputting it, it can supply operating power to the detection unit (140) and the communication unit (170). Accordingly, the detection unit (140) and the communication unit (170) can be operated for a predetermined period of time even after the power supply to the power supply unit (10) is interrupted.

[0073] Meanwhile, as shown in FIG. 6, the detection unit (140) can turn off its power by itself when it transmits the power off signal (500) to the communication unit (170). That is, by blocking the detection unit power supply circuit (141) through which operating power is supplied from the DC-DC converter (160) to the detection unit (140), the detection unit (140) can turn off its power by itself. Then, among the power supply circuits (141, 171) connected to the DC-DC converter (160), only the communication unit power supply circuit (171) is activated, so the power consumed by the smoothing capacitor (121) can be saved. Therefore, since the current (220) discharged from the smoothing capacitor (121) is reduced, the additional operating time during which the communication unit (170) can be operated after the power supply to the power supply device (10) is interrupted can be increased.

[0074] Meanwhile, when a power off signal (500) is received from the detection unit (140), the communication unit (170) can transmit a notification signal indicating that the power supply to the power supply unit (10) has been interrupted to a pre-configured upper system (e.g., a smart distribution board).

[0075] In this case, the communication unit (170) may transmit the notification signal repeatedly a preset number of times at a set time interval in preparation for the possibility that the notification signal may not be transmitted to the upper system due to communication environment issues such as collision or noise. Alternatively, the communication unit (170) may transmit the notification signal and, depending on whether an acknowledgment signal (ACK) is received from the upper system in response to the transmitted notification signal within a preset time, transmit the notification signal again.

[0076] To this end, the communication unit (170) must be able to operate for an additional period of time during which a notification signal can be transmitted more than a certain number of times based on the preset time interval after the power supply to the power supply unit (10) is interrupted. Here, the operating time of the communication unit (170) may be determined according to the charging capacity of the smoothing capacitor (121). Accordingly, the power supply unit (10) according to the embodiment of the present invention may have the capacity of the smoothing capacitor (121) determined such that sufficient charge can be charged to enable additional operation of the communication unit (170) for a period during which a notification signal can be transmitted more than a certain number of times based on the preset time interval. That is, in the power supply unit (10) according to the embodiment of the present invention, the smoothing capacitor (121) of the smoothing unit (120) may have a sufficiently large capacity or be configured with a plurality of capacitors connected in parallel, taking into account the additional operating time required by the communication unit (170). In addition, when a plurality of capacitors are configured to be connected in parallel in this manner, the DC-DC converter (160) is connected to one of the plurality of capacitors connected in parallel, and receives power from the connected capacitor to supply the operating voltage of the detection unit (140) and the communication unit (170).

[0077] Meanwhile, FIG. 7 is a graph showing the time during which the communication unit (170) can be operated when the power supply to the power supply unit (10) according to the embodiment of the present invention is interrupted.

[0078] Referring to FIG. 7, FIG. 7 illustrates a first graph (710) showing the voltage change of an electrical signal rectified in the smoothing unit (120) and a second graph (720) showing the voltage change of a DC signal converted in the DC-DC converter (160) when power supply to the power supply unit (10) is interrupted. Here, the first graph (710) represents a voltage level reduced to a voltage within a certain range (e.g., 3.3V) through the voltage reduction unit (130) for convenience.

[0079] When power supply to the power supply unit (10) is interrupted due to the off operation of the circuit breaker, there is no input electrical signal, so charging of the smoothing capacitor (121) may not occur. Therefore, only the discharge of the smoothing capacitor (121) continues, so the voltage of the electrical signal may gradually decrease. And when the voltage level of the smoothing capacitor (121) reaches a preset voltage level (711), the detection unit (140) determines that power supply to the power supply unit (10) has been interrupted and can transmit a voltage off signal to the communication unit (170).

[0080] In this case, as shown in FIG. 7 above, the detection unit (140) can determine that the power supply is interrupted when the voltage level of the smoothing capacitor (121) becomes less than the reference voltage, or when the voltage level of the smoothing capacitor (121) drops by a voltage level set based on the voltage peak value. Therefore, before all the charge charged in the smoothing capacitor (121) is discharged, a voltage off signal according to the intermediate power supply detection result can be transmitted to the communication unit (170).

[0081] Therefore, at the point (711) when a power supply interruption is detected, the smoothing capacitor (121) may still have a charged charge remaining. Accordingly, the current output from the smoothing capacitor (121) can be input to the DC-DC converter (160). And as shown in the second graph (720), the current input to the DC-DC converter (160) can be maintained until all the charged charge in the smoothing capacitor (121) is discharged.

[0082] Meanwhile, the DC-DC converter (160) converts the input current into a preset fixed voltage (e.g., 3.3V) and outputs it, so that the output of a DC current having the fixed voltage can be maintained from the DC-DC converter (160) while the current supply to the DC-DC converter (160) is maintained. Therefore, even if the power supply to the power supply unit (10) is interrupted, the operating power supply of the communication unit (170) can be maintained until all the charge charged in the smoothing capacitor (121) is discharged.

[0083] Therefore, based on the voltage drop of the smoothing capacitor (121), the operation of the communication unit (170) can be maintained for a time (730) from the point (711) when the interruption of power supply to the power supply unit (10) is detected, until the DC current output of the DC-DC converter (160) is maintained through the charge charged in the smoothing capacitor (121). Thus, even when the circuit breaker is turned off, the operation time can be secured so that the communication unit (170) can transmit a notification signal related to the interruption of power supply, i.e., the off operation of the circuit breaker, to the upper system at least once.

[0084] Meanwhile, in the above description, a configuration was described in which both the DC-DC converter (160) and the detection unit (140) are connected to the smoothing capacitor (121) of the smoothing unit (120). However, it is of course possible that the capacitor to which the detection unit (140) is connected to detect whether power is supplied, and the capacitor that supplies operating power to the DC-DC converter (160) to additionally drive the communication unit (170) after the power supply is interrupted, may be separate from each other.

[0085] FIG. 8 is a configuration diagram illustrating the configuration of another power supply device (20) according to an embodiment of the present invention.

[0086] Referring to FIG. 8, the detection unit (140) of the power supply device (20) according to another embodiment of the present invention may be connected to the smoothing capacitor (121) of the smoothing unit (120) via the voltage reduction unit (130). Accordingly, the detection unit (140) can detect the voltage level of the smoothing capacitor (121) and detect whether the power supply to the power supply device (20) is interrupted, just like the power supply device (10) described in FIG. 1.

[0087] Meanwhile, between the DC-DC converter (160) that supplies operating power to the detection unit (140) and the communication unit (170) and the smoothing unit (120), a separate capacitor, i.e., an auxiliary capacitor (150), different from the smoothing capacitor (121) may be provided. In this case, the auxiliary capacitor (150) is charged by receiving an electrical signal supplied from the smoothing unit (120), i.e., a primary rectification signal, and when the auxiliary capacitor (150) is fully charged, the primary rectification signal may be input to the DC-DC converter (160) via the auxiliary capacitor (150).

[0088] Meanwhile, the auxiliary capacitor (150) can discharge the charge stored in the DC-DC converter (160) when there is no primary rectification signal input from the smoothing unit (120). Accordingly, when power supply to the power supply unit (20) is interrupted, the DC-DC converter (160) can output a DC current of a preset voltage by receiving power stored in the auxiliary capacitor (150) rather than the smoothing capacitor (121) of the smoothing unit (120). Therefore, the capacitor (smoothing capacitor (121)) for determining whether power supply to the power supply unit (20) is interrupted and the capacitor (auxiliary capacitor (150)) for supplying operating power for additional driving to at least one of the detection unit (140) and the communication unit (170) when power supply is interrupted can be separated.

[0089] In this case, as described above, since the capacitor supplying power for additional driving to the detection unit (140) and the communication unit (170) is separated into an auxiliary capacitor (150), the capacity of the auxiliary capacitor (150) can be determined based on the minimum required driving time of the communication unit (170), that is, the time required to transmit a notification signal to the upper system a certain number of times at preset time intervals. On the other hand, the smoothing capacitor (121) of the smoothing unit (120) can have the same capacity as a conventional smoothing unit (120) since there is no need to consider the minimum required driving time of the communication unit (170).

[0090] Meanwhile, the smoothing capacitor (121) and the auxiliary capacitor (150) may be capacitors connected in parallel with each other. In this case, since the capacitance of the smoothing capacitor (121) and the auxiliary capacitor (150) is added through the parallel connection, a sufficient capacitor capacity can be formed to satisfy the minimum required driving time of the communication unit (170).

[0091] Meanwhile, FIGS. 9 to 11 are conceptual diagrams illustrating the current flow when power supply to a power supply device (20) is interrupted according to another embodiment of the present invention.

[0092] First, referring to FIG. 9, FIG. 9 illustrates an example in which an electrical signal (200) that has been rectified in the rectifier (110) is supplied to the smoothing unit (120) when an alternating current is normally supplied to the power supply unit (20). In this case, the electrical signal (200) that has been rectified in the first stage can be smoothed by charging and discharging the smoothing capacitor (121) of the smoothing unit (120). The voltage of the electrical signal (210) that is charged and discharged in the smoothing capacitor (121) can be converted into a signal having a voltage within a preset range through the voltage reduction unit (130) and input to the detection unit (140). The detection unit (140) can detect whether the power supply to the power supply unit (20) is interrupted based on the voltage level of the input electrical signal.

[0093] Meanwhile, the electrical signal (900) smoothed in the smoothing unit (120) can be supplied to at least one DC-DC converter. In this case, the DC-DC converter (160) that supplies operating power to the detection unit (140) and the communication unit (170) can also receive the smoothed electrical signal (900), convert it into a DC current according to the operating voltage of the detection unit (140) and the communication unit (170), and supply it to the detection unit (140) and the communication unit (170) through the detection unit power supply circuit (141) and the communication unit power supply circuit (171).

[0094] Here, an auxiliary capacitor (150) may be provided between the DC-DC converter (160), which supplies operating power to the detection unit (140) and the communication unit (170), and the smoothing unit (120). In this case, the auxiliary capacitor (150) may be charged by receiving the smoothed electrical signal (900). The electrical signal (910) output from the auxiliary capacitor (150) may be input to the DC-DC converter (160). That is, the DC-DC converter (160) may receive the electrical signal (910) output from the auxiliary capacitor (150), convert it into a DC current of a preset voltage, and supply it to the detection unit (140) and the communication unit (170).

[0095] Meanwhile, FIG. 10 illustrates an example in which power supply to the power supply unit (20) is interrupted due to the off operation of the circuit breaker. In this case, since power supply is interrupted, the output of an electrical signal from the rectifier (110) may be interrupted. Then, as seen in FIG. 4 and FIG. 7, only the discharge of the smoothing capacitor (121) may occur, and accordingly, the voltage of the smoothing capacitor (121), i.e., the charging voltage, may be lowered.

[0096] In this way, when the voltage of the smoothing capacitor (121) drops and reaches a preset reference voltage level, the detection unit (140) can detect that the power supply to the power supply device (20) has been interrupted. Then, the detection unit (140) can output a power off signal (1100) indicating the interruption of the power supply to the communication unit (170). And the detection unit (140) can turn off by cutting off the power itself.

[0097] Meanwhile, as described above, the present invention detects that the power supply to the power supply device (20) is interrupted when the voltage of the smoothing capacitor (121) drops below a preset reference voltage level, rather than when the smoothing capacitor (121) is completely discharged. Therefore, even when the detection result of the detection unit (140) determines that the power supply has been interrupted, the smoothing capacitor (121) may remain charged to a certain level or higher. Accordingly, even when the power supply to the power supply device (20) is interrupted, the charged charge (910) of the smoothing capacitor (121) can be discharged to the auxiliary capacitor (150). Thus, as shown in FIG. 10, a current flow from the smoothing capacitor (121) to the auxiliary capacitor (150) can be formed. And the charged charge in the auxiliary capacitor (150) can be discharged to the DC-DC converter (160). Accordingly, the DC-DC converter (160) can receive electrical energy discharged from the auxiliary capacitor (150) and supply operating power to the detection unit (140) and the communication unit (170).

[0098] Meanwhile, as described above, the auxiliary capacitor (150) may be a capacitor having sufficient capacity considering the minimum required driving time of the communication unit (170). On the other hand, the smoothing capacitor (121) is a capacitor for smoothing the primary rectified current and may be a capacitor with a smaller capacity than the auxiliary capacitor (150). Accordingly, after the power supply to the power supply unit (20) is interrupted, when all the charge charged in the smoothing capacitor (121) is discharged, the charge charged in the auxiliary capacitor (150) may start to discharge.

[0099] FIG. 11 illustrates the current flow when all the charge charged in the smoothing capacitor (121) is discharged and the charge charged in the auxiliary capacitor (150) is discharged.

[0100] Referring to FIG. 11, the power supply device (20) according to an embodiment of the present invention can maintain current input to the DC-DC converter (160) for a predetermined time using the charge (910) charged in the auxiliary capacitor (150) even when the power supply is interrupted. Accordingly, the communication unit (170) can be operated for the predetermined time even when the power supply to the power supply device (20) is interrupted.

[0101] Meanwhile, since the operation of the communication unit (170) is maintained even after the power supply to the power supply unit (20) is interrupted as described above, the communication unit (170) can transmit a notification signal to the upper system to indicate that the power supply to the power supply unit (20) has been interrupted, based on the voltage off signal (1100) received from the detection unit (140). Accordingly, even after the power supply to the power supply unit (20) has been interrupted, information related to the status of the circuit breaker (a notification signal indicating whether the power supply has been interrupted) can be collected by the upper system from the power supply unit (20).

[0102] Furthermore, depending on the capacity of the auxiliary capacitor (150), a minimum operating time is secured during which the communication unit (170) can transmit the notification signal to the upper system more than a preset number of times, thereby ensuring robustness against poor wireless environments such as noise and reliable status information regarding the circuit breaker status information of the power supply unit (20).

[0103] Meanwhile, FIG. 12 is a flowchart showing the operation process of a power supply device according to an embodiment of the present invention. In the following description, it will be assumed that the power supply device is the power supply device (10) according to the first embodiment of the present invention described in FIGS. 1 to 7. However, it is understood that the power supply device (20) according to another embodiment of the present invention described in FIGS. 8 to 11 can also be applied in the same way to the following description. However, in the case of the power supply device (20) according to another embodiment of the present invention, in the following description, the auxiliary capacitor (150) may supply power to the DC-DC converter (160) in place of the smoothing capacitor (121).

[0104] Referring to FIG. 12, when an alternating current is input to a power supply device according to an embodiment of the present invention, a process of rectifying the input alternating current into a pulsating electric signal may first be performed in the rectifier unit (110) of the power supply device (S1200). Then, a process of smoothing the rectified pulsating electric signal may be performed in the smoothing unit (120) of the power supply device (S1202).

[0105] And when the above pulsating electrical signal is smoothed, the DC-DC converter (160) can receive the smoothed pulsating signal and convert it into a DC current having a preset voltage. Then, the converted DC current can be supplied as the operating power for the detection unit (140) and the communication unit (170) (S1204).

[0106] Meanwhile, if power supply to the power supply unit is interrupted, there is no input current, so the rectification of the rectifier unit (110) may be interrupted. Additionally, the smoothing process of the smoothing unit (120) may also be interrupted. However, since the smoothing capacitor (121) of the smoothing unit (120) still has charged power remaining, the electrical energy charged in the smoothing capacitor (121) may be discharged.

[0107] In this case, the DC-DC converter (160) can be connected to the smoothing capacitor (121). Therefore, the DC-DC converter (160) can receive power from the connected smoothing capacitor (121). That is, even if the power supply to the power supply unit is interrupted, the DC-DC converter (160) can be driven by the electrical energy charged in the smoothing capacitor (121) (S1206). Accordingly, the operation of the DC-DC converter (160) can be maintained for a predetermined time even after the power supply to the power supply unit is interrupted.

[0108] Meanwhile, the detection unit (140) can detect the voltage level of the smoothing capacitor (121). In this case, when the power supply is interrupted, the charged electrical energy of the smoothing capacitor (121) is discharged, so the voltage of the smoothing capacitor (121) may decrease. Therefore, the detection unit (140) can detect that the power supply to the power supply device has been interrupted based on the voltage level detected from the smoothing capacitor (121). For example, the detection unit (140) can determine that the power supply has been interrupted if the detected voltage drops below a preset level, or if the detected voltage level of the smoothing capacitor is below a preset voltage level. And if it is determined that the power supply to the power supply device has been interrupted, a voltage off signal indicating the interruption of the power supply can be transmitted to the communication unit (170) (S1208). And the detection unit (140) can turn off the power itself to prevent power supply to the detection unit (140).

[0109] Meanwhile, as described above, since the operation of the DC-DC converter (160) is maintained even after the power supply to the power supply unit is interrupted, the power supply to the communication unit (170) can be maintained. Accordingly, the communication unit (170) can receive a voltage off signal transmitted from the detection unit (140), and can transmit a notification signal to the upper system indicating that the power supply to the power supply unit has been interrupted according to the received voltage off signal (S1210). In this case, the notification signal can be transmitted a preset number of times until the power supply to the communication unit (170) is interrupted. That is, the communication unit (170) can be operated until all the power charged in the smoothing capacitor (121) is discharged.

[0110] Accordingly, the power supply device according to an embodiment of the present invention can operate for a predetermined period of time even after the power supply to the power supply device has been interrupted, thereby transmitting to an upper system that the power supply has been interrupted. Therefore, it is possible to collect reliable information related to the operating status of the circuit breaker.

[0111] Meanwhile, although specific embodiments have been described in the above description of the present invention, various modifications may be implemented without departing from the scope of the present invention. In particular, in the embodiment of the present invention, a configuration was described in which the detection unit (140) immediately transmits a power off signal to the communication unit (170) and turns off the power itself to secure the operating time of the communication unit (170) when it detects that the power supply to the power supply device has been interrupted; however, alternatively, the detection unit (140) may determine whether to interrupt the power supply to the power supply device based on the result of detecting a preset number of times.

[0112] For example, the detection unit (140) may presume that the power supply to the power supply unit has been interrupted if the voltage level detected from the smoothing capacitor (121) is below a preset voltage level. Then, if the power supply interruption is presumed, the detection unit may check again whether the voltage level detected from the smoothing capacitor (121) is below the preset voltage level after a preset time has elapsed. And if, as a result of the recheck, the voltage level detected from the smoothing capacitor (121) is below the preset voltage level, the power supply to the power supply unit is confirmed to have been interrupted, and if the power supply interruption is confirmed, the power off signal can be transmitted to the communication unit (170).

[0113] In this way, the power supply to the power supply unit (20) is estimated to be interrupted based on the voltage level of the smoothing capacitor (121) in the first instance, and if it is estimated that the power supply has been interrupted, the voltage level of the smoothing capacitor (121) is detected again to finally determine whether the power supply has been interrupted. This prevents the misjudgment that the power supply to the power supply unit (20) is interrupted when the voltage level of the smoothing capacitor (121) decreases due to temporary noise, etc.

[0114] The foregoing invention may be implemented as computer-readable code on a medium on which a program is recorded. A computer-readable medium includes all types of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable media include HDD (Hard Disk Drive), SSD (Solid State Disk), SSD (Silicon Disk Drive), ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc., and also include implementations in the form of a carrier wave (e.g., transmission over the Internet). Furthermore, the computer may include a detection unit or a communication unit of the power supply. Accordingly, the above detailed description should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the invention are included within the scope of the invention.

Claims

Claim 1 A power supply device comprises: a rectifier unit that rectifies an alternating current input via a circuit breaker; a smoothing unit that includes at least one smoothing capacitor and smooths an electrical signal rectified by the rectifier unit; a detection unit that detects whether power supply to the power supply unit is interrupted through a voltage change of the smoothing capacitor that drops when power supply to the power supply unit is interrupted, and outputs a power supply interruption signal according to the detection result; a communication unit that receives the power supply interruption signal and transmits a notification signal pre-set in an upper system; and a DC-DC converter that receives the current smoothed by the smoothing unit and supplies operating power for driving the detection unit and the communication unit. A power supply device comprising: an auxiliary capacitor provided between the smoothing unit and the DC-DC converter, which is charged by receiving the smoothed current from the smoothing unit and discharges the power charged in the DC-DC converter when the power supply to the power supply unit is interrupted; wherein the DC-DC converter is connected to the auxiliary capacitor and, when the power supply to the power supply unit is interrupted, receives the current discharged from the auxiliary capacitor to supply operating power for driving the detection unit and the communication unit; and wherein the detection unit outputs the power supply interruption signal to the communication unit and then cuts off the current supplied from the DC-DC converter to the detection unit to turn off itself. Claim 2 A power supply device according to claim 1, wherein the capacity of the smoothing capacitor is determined according to a minimum required driving time determined by the time during which the communication unit can transmit the notification signal to the upper system a preset number of times after the power supply to the power supply device is interrupted. Claim 3 A power supply device according to claim 1, wherein the detection unit detects that the power supply of the power supply device is interrupted when the voltage level detected from the smoothing capacitor drops by a voltage level set based on the voltage peak value of the smoothing capacitor. Claim 4 A power supply device according to paragraph 3, wherein the above-mentioned preset voltage level is determined according to the magnitude of the ripple voltage determined from the smoothed electrical signal. Claim 5 delete Claim 6 A power supply device according to paragraph 3, wherein the DC-DC converter supplies operating power for driving at least one of the detection unit and the communication unit from the time when the voltage level detected from the smoothing capacitor drops by the preset voltage level until the time when all the charge charged in the smoothing capacitor is discharged. Claim 7 A power supply device according to claim 1, wherein the detection unit detects the voltage level of the smoothing capacitor again a predetermined number of times at a predetermined time interval when the voltage level detected from the smoothing capacitor drops by the preset voltage level, and outputs the power supply interruption signal to the communication unit when the voltage of the smoothing capacitor detected again a predetermined number of times is less than or equal to the preset voltage level. Claim 8 A power supply device according to claim 1, wherein the smoothing capacitor is configured by connecting a plurality of capacitors in parallel, and the DC-DC converter is connected to any one of the plurality of parallel-connected capacitors, and converts the power supplied from the connected capacitor to supply it as an operating power for driving the detection unit and the communication unit. Claim 9 delete Claim 10 A power supply device according to claim 1, wherein the auxiliary capacitor is characterized by having a capacity determined according to a minimum required driving time determined by the time during which the communication unit can transmit the notification signal to the upper system a preset number of times after the power supply to the power supply device is interrupted. Claim 11 A method of operation of a power supply comprises: a step in which a rectifier unit rectifies an alternating current input to the power supply unit via a circuit breaker; a step in which a smoothing unit including at least one smoothing capacitor smooths the rectified electrical signal; a step in which a DC-DC converter converts the smoothed electrical signal into a direct current having a preset voltage and supplies it as an operating power source for a detection unit and a communication unit of the power supply unit; a step in which an auxiliary capacitor provided between the smoothing unit and the DC-DC converter receives and charges the smoothed electrical signal; a step in which, when power supply to the power supply unit is interrupted, the DC-DC converter converts the electrical energy discharged from the auxiliary capacitor and supplies it as an operating power source for the detection unit and the communication unit; and a step in which, after power supply to the power supply unit is interrupted, a detection unit driven by the electrical energy discharged from the auxiliary capacitor detects the voltage level of the auxiliary capacitor to detect whether power supply to the power supply unit is interrupted and outputs a voltage off signal to the communication unit. A method of operation of a power supply device characterized by comprising: a step in which the detection unit, after outputting the voltage off signal, cuts off the current supplied from the DC-DC converter to the detection unit to turn off itself; and a step in which, after power supply to the power supply device is interrupted, a communication unit driven by electrical energy discharged from the auxiliary capacitor receives the voltage off signal and transmits a preset notification signal to an upper system. Claim 12 delete Claim 13 A method of operation of a power supply device according to claim 11, wherein the step of the communication unit transmitting the notification signal to the upper system is characterized by the step of transmitting the notification signal repeatedly a predetermined number of times during the time from when the detection unit detects the interruption of power supply to the power supply device according to the voltage level of the smoothing capacitor until when all the charge charged in the smoothing capacitor is discharged.

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