TWI663411B - Power monitor - Google Patents

Abstract

A power monitor includes a detection circuit, a processing circuit, and a warning circuit. The detection circuit is used to detect a first abnormal state of the primary circuit of the power converter and a second abnormal state of the secondary circuit. The processing circuit calculates a first level and a first occurrence number of the first abnormal state, and calculates a second level and a second occurrence number of the second abnormal state. The processing circuit is used to determine whether the first occurrence number exceeds a first preset number corresponding to the first level, and if so, the processing circuit outputs a first abnormal signal. The processing circuit is further configured to determine whether the second occurrence number exceeds a second preset number corresponding to the second level, and if so, the processing circuit outputs a second abnormal signal. The warning circuit sends a warning signal according to the first abnormal signal or the second abnormal signal.

Description

Power monitor

This case relates to a monitoring device, and in particular to an intelligent power monitor.

In industrial applications, all types of machines that manufacture products require a stable and continuous power source to avoid abnormal power supply or even power outages, leading to loss of the factory.

In order to avoid abnormal power supply and power failure, it is known that the power supply device has two power supplies. When one of the power supplies is out of order and needs to be repaired, there is another power supply to maintain power supply, or a Uninterruptible Power System (UPS) to provide power to the machine when the power supply device is damaged / disconnected.

However, the conventional power supply device must be equipped with two power supplies, which is costly, and the conventional power supply device is damaged whether it is the way to start another power supply or the way to maintain power supply by the UPS system. / Remedial measures after power failure, damage to the power supply device / loss caused by the power plant is huge, even difficult to estimate, so how to reduce the cost of the power supply device, and how to effectively avoid damage to the power supply device / power failure, It is one of the main topics studied by those skilled in the art.

This summary is intended to provide a simplified summary of this disclosure so that readers may have a basic understanding of this disclosure. This summary is not a comprehensive overview of this disclosure, and it is not intended to point out important / critical elements of the embodiments of the invention or to define the scope of the invention.

One of the contents of this case is to provide a power monitor to solve the problems existing in the prior art. The solution is as described below.

In order to achieve the above purpose, one aspect of the technical content of this case is a power monitor, which includes a detection circuit, a processing circuit, and a warning circuit. The detection circuit detects a first abnormal state of the primary circuit of the power converter and a second abnormal state of the secondary circuit. The processing circuit calculates a first level and a first occurrence number of the first abnormal state, and calculates a second level and a second occurrence number of the second abnormal state. The processing circuit determines whether the first occurrence number exceeds a first preset number corresponding to the first level, and if so, the processing circuit outputs a first abnormal signal. The processing circuit further determines whether the second occurrence number exceeds a second preset number corresponding to the second level, and if so, the processing circuit outputs a second abnormal signal. The warning circuit sends a warning signal according to the first abnormal signal or the second abnormal signal.

In order to achieve the above object, another technical aspect of the present invention relates to a power monitor, which includes a detection circuit, a processing circuit, and a warning circuit. The detection circuit detects the input voltage of the input capacitor of the primary circuit of the power converter. The processing circuit is used to compare the state of the input voltage with the preset parameter. If the state of the input voltage is different from the preset parameter, the processing circuit outputs an abnormal signal. The warning circuit is used to issue a warning signal according to the abnormal signal.

Therefore, according to the technical content of the present case, the power monitor shown in the embodiment of the present case can reduce the cost of the power supply device, and can effectively avoid damage / power failure of the power supply device.

After referring to the following embodiments, those with ordinary knowledge in the technical field to which this case belongs can easily understand the basic spirit and other inventive objectives of this case, as well as the technical means and implementation patterns used in this case.

In order to make the description of this disclosure more detailed and complete, the following provides an illustrative description of the implementation mode and specific embodiments of this case; but this is not the only form of implementing or using the specific embodiments of this case. The embodiments include the features of a plurality of specific embodiments, as well as the method steps and their order for constructing and operating these specific embodiments. However, other specific embodiments can also be used to achieve the same or equal functions and sequence of steps.

Unless otherwise defined in this specification, the meanings of scientific and technical terms used herein are the same as those understood and used by those having ordinary knowledge in the technical field to which this case belongs. In addition, when not in conflict with the context, the singular noun used in this specification covers the plural form of the noun; and the plural noun used also covers the singular form of the noun.

In addition, as used in this document, "coupling" may mean that two or more elements make direct physical or electrical contact with each other, or indirectly make physical or electrical contact with each other, or that two or more elements operate mutually Or action.

FIG. 1 is a schematic circuit block diagram of a power supply device according to an embodiment of the present invention. As shown, the power supply device includes a power converter 100 and a power monitor 200. The power monitor 200 includes a detection circuit 210, a processing circuit 220, a warning circuit 230, and a communication circuit 240. In terms of connection, the power converter 100 is connected to a power source 800 and a load 900. The detection circuit 210 is connected to the primary-side circuit 110 of the power converter 100 and is connected to the secondary-side circuit 120 of the power converter 100. The processing circuit 220 is connected to the detection circuit 210. The warning circuit 230 is connected to the processing circuit 220. The communication circuit 240 is connected to the warning circuit 230.

In operation, the power converter 100 converts the power provided by the power source 800 to provide the load 900. In an embodiment, the power source 800 may be a power grid or other external power source. The power monitor 200 is used to monitor the status of the power converter 100 and immediately notify the user when the power converter 100 is abnormal, so as to effectively avoid damage / power failure of the power supply device, as described later.

The detection circuit 210 of the power monitor 200 detects the first abnormal state of the primary circuit 110 and the second abnormal state of the secondary circuit 120 in real time. The processing circuit 220 then calculates the first level and the first occurrence number of the first abnormal state, and calculates the second level and the second occurrence number of the second abnormal state. For example, when the power provided by the power source 800 is high, the primary circuit 110 receives a higher voltage. At this time, the detection circuit 210 detects this abnormal state, and the processing circuit 220 calculates the abnormal state. Level (such as voltage of 1000 volts / voltage of 750 volts are two different levels) and the number of occurrences of abnormal conditions. In addition, when the power demand of the load 900 increases, the secondary circuit 120 will be overloaded. At this time, the detection circuit 210 will detect this abnormal state, and the processing circuit 220 will calculate the level of the abnormal state (such as 10 seconds overload time / 3 seconds overload time are two different levels) and the number of occurrences of abnormal conditions.

Next, the processing circuit 220 of the power monitor 200 further determines whether the first occurrence number exceeds a first preset number corresponding to the first level. If so, the processing circuit 220 outputs a first abnormal signal. In addition, the processing circuit 220 determines whether the second occurrence number exceeds a second preset number corresponding to the second level, and if so, the processing circuit 220 outputs a second abnormal signal. In one embodiment, the processing circuit 220 obtains a first preset number of times corresponding to the first level and a second preset number of times corresponding to the second level from the lookup table. For example, the processing circuit 220 will obtain the corresponding preset number of times according to the abnormal state level of the primary circuit 110 (such as voltage 1000 volts / voltage 750 volts). For example, when the abnormal state level is 1000 volts, The higher the damage to the primary circuit 110 is, the more it can withstand the preset voltage of 1000 volts for 5 times. Once the primary circuit 110 is impacted more than 5 times, the processing circuit 220 outputs an abnormal signal. In contrast, if the abnormal state is at a voltage of 750 volts, the voltage on the primary circuit 110 is relatively small and the damage to the primary circuit 110 is small. Therefore, the number of times that the preset voltage 750 volt can withstand is 20 times. 110 is impacted more than 20 times before processing circuit 220 outputs an abnormal signal.

The state of the secondary circuit 120 is that the processing circuit 220 obtains a corresponding preset number of times according to the abnormal state level of the secondary circuit 120 (such as an overload time of 10 seconds / overload time of 3 seconds). For example, when the level of the abnormal state is 10 seconds of overload, the secondary circuit 120 will be damaged greatly due to the high overload time. Therefore, the preset number of times of overload for 10 seconds is 50 times. Once the secondary circuit 120 occurs In the case of overload for more than 50 times, the processing circuit 220 outputs an abnormal signal. In contrast, if the level of the abnormal state is 3 seconds of overload, the overload time is relatively low, and the damage to the secondary circuit 120 is small. Therefore, the preset number of times of overload for 3 seconds is 100 times. Only when the secondary circuit 120 is overloaded more than 100 times will the processing circuit 220 output an abnormal signal.

Furthermore, the warning circuit 230 may issue a warning signal according to a first abnormal signal corresponding to the primary circuit 110, or issue a warning signal according to a second abnormal signal corresponding to the secondary circuit 120. For example, when the primary circuit 110 is impacted by a voltage of 1000 volts more than 5 times, the degree of tolerance of damage to the internal components of the primary circuit 110 may have reached the upper limit. Continued use may cause damage at any time. 230 will issue a warning to remind the user to replace the internal components of the primary circuit 110 to avoid damage / power failure of the power supply device. Similarly, when the secondary side circuit 120 is overloaded for 10 seconds for more than 50 times, the degree of tolerance of damage to the internal components of the secondary side circuit 120 may have reached the upper limit, and continued use may be damaged at any time. At this time, a warning The circuit 230 will issue a warning to remind the user to replace the internal components of the secondary circuit 120 to avoid damage / power failure of the power supply device.

The abnormal state of the primary circuit 110 and the secondary circuit 120 of the power converter 100 in this case is not limited to the above embodiment. The abnormal state of the primary circuit 110 may be an abnormal voltage, an abnormal current, a surge, or other damage to the circuit. The abnormal state of the secondary circuit 120 includes an abnormal voltage, an abnormal current, an overload, or other conditions that cause the circuit to be damaged.

In one embodiment, the power monitor 200 of this case can be used for remote monitoring. The power monitor 200 may include a communication circuit 240. When the primary circuit 110 or the secondary circuit 120 of the power converter 100 is abnormal, the communication signal may be transmitted to the remote monitoring system through a wired or wireless communication circuit 240 ( (Not shown in the figure), so that users can perform unified monitoring at the remote end. Once an abnormality is found, immediately ask the person closest to the abnormal power converter 100 to handle it. In addition, the power monitor 200 can detect the primary side circuit 110 or the secondary side circuit 120 of the power converter 100 through the detection circuit 210 to generate detection data, and then use the communication circuit 240 to generate detailed detection data ( Such as: abnormal conditions) transmitted to the remote monitoring system, the remote monitoring system collects all states for big data analysis, and adaptively adjusts the parameters of the power monitor 200 or the above look-up table according to the analysis results to enable power monitoring The device 200 performs monitoring and alerting more intelligently.

FIG. 2 is a schematic diagram of a power converter 100 of the power supply device shown in FIG. 1 according to an embodiment of the present invention. FIG. 2 exemplarily illustrates the detailed circuit of the power converter 100 of FIG. 1 for illustration. For example, the power converter 100 here uses a flyback converter for explanation. However, this case is not limited to this circuit. The power converter 100 may also use a forward converter, a half-bridge converter, a full-bridge converter, or other types of converters.

Please refer to FIG. 1 and FIG. 2 together. The detection circuit 210 of the power monitor 100 is used to detect the voltage across the input capacitor C of the primary circuit 110 (also referred to as input voltage herein). Next, the processing circuit 220 is used to compare the state of the input voltage with the preset parameter. If the state of the input voltage is different from the preset parameter, the processing circuit 220 outputs an abnormal signal, and the warning circuit 230 sends a warning signal according to the abnormal signal. The signal is transmitted to the remote monitoring device (not shown) via the communication circuit 240 to notify the user. In addition, for a detailed description of the power monitoring technology in this case, please refer to FIG. 3, which is a schematic diagram of a voltage waveform according to an embodiment of the case. The voltage waveform W1 in FIG. 3 is a voltage waveform on the input capacitor C of the primary-side circuit 110 shown in FIG. 2, and the voltage waveform W2 in FIG. 3 is a voltage-waveform on the secondary-side circuit 120 shown in FIG. 2. Output voltage waveform. This case has a variety of power monitoring technologies, as detailed below.

Please refer to FIGS. 1-3 together. In terms of valley detection, the processing circuit 220 is used to compare whether the valley of the input voltage W1 is lower than the preset valley voltage. For example, set a preset valley voltage L2. The valley of the voltage W1 is lower than the preset valley voltage L2 (such as point A in FIG. 3), which indicates that an abnormality has occurred. At this time, the processing circuit 220 outputs an abnormal signal. As the input capacitor C is subject to aging after a period of use, for example, when the input capacitor is an electrolytic capacitor, the electrolyte therein will gradually decrease with time, resulting in a decrease in its efficiency. The conventional detection method is to detect the output voltage W2 of the secondary circuit. When the output voltage W2 is abnormal, a warning is issued. However, as mentioned above, the component causing the problem is actually in the primary circuit, which causes the input voltage W1. Decrease, it is known that the output voltage W2 of the secondary circuit is detected to warn, which is actually caused by inversion. If the valley detection in this case is used as the power monitoring method, the input capacitor C of the primary circuit 110 can be directly / efficiently detected. (If the input voltage W1 is lower than the preset valley voltage L2, it means the input. Capacitor C is aging) to be replaced immediately. In this way, the performance of the power supply device can be prevented from decreasing / damaging in advance, and the output ripple can be prevented from increasing.

In terms of peak detection, the processing circuit 220 is used to compare whether the peak value of the input voltage W1 is higher than a preset peak voltage. For example, a preset peak voltage L1 is set. Once the peak value of the input voltage W1 is higher than the preset peak voltage, L1 represents the occurrence of an abnormality. At this time, the processing circuit 220 outputs an abnormal signal. In order to detect whether the power provided by an external power source (such as the power grid) is abnormal, the conventional detection method is also to detect the output voltage W2 of the secondary circuit. When the output voltage W2 is abnormal, a warning is performed. However, as described above, The problem actually occurs at the primary circuit receiving the external power supply, which causes the input voltage W1 to increase. It is known to detect the output voltage W2 of the secondary circuit and issue a warning. It is also a causal inversion method. As the power source monitoring method, the peak detection in this case can detect the input voltage W1 of the primary circuit 110 in real time. If the number of peaks exceeds too many times, the input capacitor C will be seriously damaged. At this time, it can be replaced immediately. In this way, it is possible to prevent the performance of the power supply device from decreasing / damaging in advance, thereby preventing the output ripple from increasing.

In terms of difference detection, the processing circuit 220 is used to compare whether the fluctuation of the input voltage is higher than the preset voltage difference. If the fluctuation of the input voltage is higher than the preset voltage difference, it represents the power provided by the power supply 800. If the fluctuation is too large, the input capacitor C will also be damaged. The conventional detection method is also to detect the output voltage W2 of the secondary circuit. When the output voltage W2 is abnormal, a warning is issued. However, as mentioned above, the problem actually occurs at the primary circuit receiving the input voltage W1. The conventional method of detecting the output voltage W2 of the secondary circuit for warning is also a method of causal inversion. If the difference detection in this case is used as a power monitoring method, if the number of excessive fluctuations is too large, which causes serious damage to the input capacitor C of the primary circuit 110, it can be replaced immediately. In this way, the performance of the power supply device can be prevented in advance. Damage, which prevents the output ripple from increasing.

In terms of unit time change rate detection, the processing circuit 220 is used to compare whether the unit time change rate of the waveform of the input voltage is higher than the preset unit time change rate. If the unit voltage time change rate of the input voltage is higher than the preset unit time change The rate (such as at point B in Figure 3) indicates that an overload condition has occurred. In this way, the input capacitor C will also be damaged. If the number of overloads is too many, the input capacitor C will be seriously damaged. At this time, it can be performed immediately. Replacement, in this way, can prevent the power supply device from reducing / damaging the performance in advance, thereby preventing the output ripple from increasing. In addition, when an overload condition occurs, that is, when the output current of the secondary circuit 120 is too high (for example, higher than a preset output current), the processing circuit 220 first sends a protection signal to the remote monitoring system (not shown in the figure). (Shown), the overall monitoring is performed by the remote monitoring system, and the power converter 100 is controlled in advance by the remote monitoring system to prevent damage to the power supply device. Thereafter, the processing circuit 220 sends an abnormal signal to the warning circuit 230, and then the warning circuit 230 Send a warning signal to notify the user to take relevant actions. For example, the processing circuit 220 may first send a protection signal to the remote monitoring system, and the remote monitoring system may replace the power converter 100, perform load shedding on the power converter 100, or perform other appropriate treatments. Before the related processing is performed, the power converter 100 is protected accordingly to further prevent the power supply device from being damaged.

FIG. 4 is a schematic diagram of a pulse width modulation waveform according to an embodiment of the present invention. In combination with the control method of the switches in the primary circuit 110 in FIG. 2 as pulse width modulation (PWM) control as an example, the width of the pulse width modulation signals P1-P3 is normal. After the pulse width modulation signal P4 The width began to increase. Until the width of the pulse width modulation signal P6 is too large, it indicates that an abnormal condition has occurred, which may be caused by an overload condition. In this case, the width of the pulse width modulation signal is used as a power monitoring method. The width of the pulse width modulation signal is preset. For example, the width of the pulse width modulation signal is the width of the pulse width modulation signal P5. Once the processing circuit 210 compares the primary circuit, When the width of the pulse width modulation signal of the switch in 110 is different from the preset width (for example, when the width of the pulse width modulation signal is different from the preset width), the processing circuit 210 outputs an abnormal signal in advance instead of waiting for an abnormal condition ( Such as pulse width modulation (P6), an abnormal signal is output for warning. In this way, degradation / damage of the performance of the power supply device can be prevented in advance. Furthermore, in terms of frequency detection, when the control mode of the switches in the primary circuit 110 is changed to Pulse Frequency Modulation (PFM), the processing circuit 210 compares whether the control signal frequency of the switches in the primary circuit 110 is Different from the preset frequency (for example, the control signal frequency is different from the preset frequency), if the frequency of the pulse frequency modulation signal of the switch in the primary circuit 110 is different from the preset frequency, the processing circuit 210 outputs an abnormal signal. For example, the normal frequency range of the pulse frequency modulation signal is 60kHz-80kHz. When the frequency of the pulse frequency modulation signal is 200kHz, it means that an abnormal condition occurs, which may be caused by an overload condition. In this case, the pulse frequency modulation signal is used as a power monitoring means, and a frequency such as 100 kHz is preset. Once the processing circuit 210 compares the frequency of the pulse frequency modulation signal of the switch in the primary circuit 110 to be higher than the preset frequency, the processing circuit 210 advances Output an abnormal signal instead of waiting until an abnormal condition occurs (for example, when the frequency of the pulse frequency modulation is 200 kHz) to output an abnormal signal for warning. In this way, degradation / damage of the performance of the power supply device can be prevented in advance.

It can be known from the foregoing embodiments of the present application that the application of the present application has the following advantages. The embodiment of the present case provides a power monitor. Since the power monitor of the case can intelligently predict the condition of the power converter and perform component replacement or other appropriate disposal, the power converter can be maintained in a normal state with almost no damage. Compared with the power supply device of the prior art, in order to avoid damage / power failure, two power supply devices are required. In this case, only a single power supply device is required. Therefore, the cost of the power supply device is reduced. Replace the aging components to maintain the power supply in a high efficiency state, and then prevent the output ripple from becoming larger or other conditions that do not meet the rated specifications of the power supply device.

Although the specific embodiments of the present case are disclosed in the above embodiments, they are not intended to limit the present case. Those who have ordinary knowledge in the technical field to which this case belongs can be carried out without departing from the principles and spirit of this case. Various changes and modifications, so the scope of protection in this case shall be defined by the scope of the accompanying patent application.

100‧‧‧ Power Converter

110‧‧‧Primary circuit

120‧‧‧ secondary circuit

200‧‧‧ Power Monitor

210‧‧‧detection circuit

220‧‧‧Processing circuit

230‧‧‧Warning circuit

240‧‧‧communication circuit

800‧‧‧ Power

900‧‧‧ load

A‧‧‧ Valley Point

B‧‧‧ unit rate change point

C‧‧‧input capacitor

L1‧‧‧ preset peak voltage

L2‧‧‧ preset valley voltage

W‧‧‧ waveform

In order to make the above and other objects, features, advantages, and embodiments of the present case more comprehensible, the description of the drawings is as follows: FIG. 1 is a schematic circuit block diagram of a power supply device according to an embodiment of the present case. FIG. 2 is a schematic diagram of a power converter of the power supply device shown in FIG. 1 according to an embodiment of the present invention. FIG. 3 is a schematic diagram of a voltage waveform according to an embodiment of the present invention. FIG. 4 is a schematic diagram of a pulse width modulation waveform according to an embodiment of the present invention. According to the usual operation method, the various features and components in the figure are not drawn to scale. The drawing method is to present the specific features and components related to the case in the best way. In addition, between different drawings, the same or similar element symbols are used to refer to similar elements / components.

Claims (15)

A power monitor includes: a detection circuit for detecting a first abnormal state of a DC voltage of a primary circuit of a power converter and a second abnormal state of a secondary circuit; a processing circuit, Used to calculate a first level and a first occurrence number of the first abnormal state, and calculate a second level and a second occurrence number of the second abnormal state, wherein the processing circuit determines whether the first occurrence number is Exceeds a first preset number of times corresponding to the first level, and if so, the processing circuit outputs a first abnormal signal, wherein the processing circuit determines whether the second occurrence number exceeds a second number of times corresponding to the second level The preset number of times, if yes, the processing circuit outputs a second abnormal signal; and a warning circuit for issuing a warning signal according to the first abnormal signal or the second abnormal signal. The power monitor according to claim 1, wherein the processing circuit obtains the first preset number of times corresponding to the first level from a lookup table, and obtains the second preset number of times corresponding to the second level . The power monitor according to claim 2, wherein the warning circuit comprises a communication circuit for transmitting the warning signal to a remote monitoring system. The power monitor according to claim 3, wherein the detection circuit is further configured to detect a primary circuit and a secondary circuit of the power converter to generate a detection data, and the communication circuit transmits the detection data To the remote monitoring system, the remote monitoring system analyzes the detection data, and adjusts the parameters of the lookup table according to the analysis result. The power monitor according to any one of claims 1-4, wherein the power converter includes one of a forward converter, a flyback converter, a half-bridge converter, and a full-bridge converter. The power monitor according to any one of claims 1-4, wherein the first abnormal state of the primary circuit includes one of an abnormal voltage, an abnormal current, and a surge. The power monitor according to any one of claims 1-4, wherein the second abnormal state of the secondary circuit includes one of an abnormal voltage, an abnormal current, and an overload. A power monitor includes: a detection circuit for detecting an input voltage of an input capacitor of a primary circuit of a power converter; and a processing circuit for comparing a state of the input voltage with a preset parameter If the state of the input voltage is different from the preset parameter, the processing circuit outputs an abnormal signal; and a warning circuit for issuing a warning signal according to the abnormal signal. The power monitor according to claim 8, wherein the processing circuit is used to compare whether the valley of the input voltage is lower than a preset voltage, and if the valley of the input voltage is lower than the preset voltage, the processing circuit outputs the exception signal. The power monitor according to claim 8, wherein the processing circuit is used to compare whether the peak of the input voltage is higher than a preset voltage, and if the peak of the input voltage is higher than the preset voltage, the processing circuit outputs the exception signal. The power monitor according to claim 8, wherein the processing circuit is used to compare whether the fluctuation difference of the input voltage is higher than a preset voltage difference, and if the fluctuation difference of the input voltage is higher than the preset voltage difference Value, the processing circuit outputs the abnormal signal. The power monitor according to claim 8, wherein the processing circuit is used to compare whether the rate of change in the unit time of the waveform of the input voltage is higher than a preset rate of change in the unit time. If the rate of change in the unit time of the waveform of the input voltage is higher than For the preset unit time change rate, the processing circuit outputs the abnormal signal. The power monitor according to claim 8, wherein the processing circuit is used to compare whether the width of the pulse width modulation of the switch in the primary circuit is different from a preset width. If the pulse width of the switch in the primary circuit is adjusted, The changed width is different from the preset width, and the processing circuit outputs the abnormal signal. The power monitor according to claim 8, wherein the processing circuit is used to compare whether the frequency of the switch in the primary circuit is different from a preset frequency. If the frequency of the switch in the primary circuit is different from the preset frequency, The processing circuit outputs the abnormal signal. The power monitor according to claim 8, wherein the detection circuit is further configured to detect the output current of the secondary circuit of the power converter, and the processing circuit compares and determines the secondary circuit of the power converter When the output current is higher than a preset output current, the processing circuit outputs the abnormal signal after sending a protection signal to a remote monitoring system.