JP2009011107A - Repair information notification device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a repair information notification device that notifies repair information of a power supply part in CATV equipment by monitoring an actual operating state of an electrolytic capacitor. <P>SOLUTION: The repair information notification device 1 includes a pulsating-voltage-signal generating part 11, which generates a pulsating voltage signal by removing a DC component from a voltage charged/discharged by an electrolytic capacitor for smoothing pulsation of a DC current included in a conversion circuit that converts an AC current into a DC current, a high-frequency-component removing part 12, which removes a high frequency higher than four times an AC frequency from the pulsating voltage signal, a voltage-signal generating part 13 for generating a voltage signal proportional to a voltage of the pulsating voltage signal with no high frequency, a threshold-signal generating part 14 for generating at least one predetermined threshold signal, and a repair information notification part 15 that notifies repair information when the voltage signal becomes larger than the threshold signal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a repair information notification device, and more particularly, to a repair information notification device that notifies repair information of a power supply unit of a CATV device.

  Currently, a television signal transmission device used in a CATV system has a built-in power supply unit, a transmission unit and a power supply unit, and a transmission unit is connected from the power supply unit via a coaxial cable or the like. There are some that supply electric power. Regardless of the format, the transmission unit operates with DC power, and the power supply unit includes a conversion circuit that converts AC to DC. Since this conversion circuit needs to reduce as much as possible the pulsation component that becomes noise for a television signal, it usually includes a smoothing circuit in which an electrolytic capacitor and a coil are combined.

  However, the performance of the electrolytic capacitor deteriorates with time due to deterioration, leakage, etc. of the electrolytic solution, and as the deterioration progresses, the pulsation of the DC power supplied by the power supply unit increases.

  In conventional analog television broadcasting, the television signal transmitted by the CATV device is an analog signal. When the pulsation of the DC power supplied by the power supply unit is increased due to deterioration of the performance of the electrolytic capacitor, the image quality of the television receiver is improved. to degrade. For this reason, it was possible to determine the repair time of the power supply unit including the electrolytic capacitor from the image quality.

  However, in digital television broadcasting that will become the mainstream in the future, since the television signal transmitted by the CATV device is a digital signal, even if the performance of the electrolytic capacitor deteriorates and the pulsation of DC power supplied by the power supply unit increases, The image quality is not gradually deteriorated, and it is expected that the CATV device suddenly stops operating.

  In order to avoid such a sudden stoppage of operation, it is necessary to monitor whether or not the electrolytic capacitor has deteriorated, and if it is determined that the electrolytic capacitor has deteriorated, it is necessary to notify it as repair information. Become.

As for the deterioration of the electrolytic capacitor, a self-diagnosis device or the like as described in JP-A-2000-2222025 is known.
JP 2000-2222025 A

  However, the self-diagnosis device as described in the above-mentioned Patent Document 1 determines the deterioration of the electrolytic capacitor based on the energization time to the electrolytic capacitor. What is the energization time and performance degradation to the electrolytic capacitor? It is not necessarily a linear relationship, and when it deteriorates at a speed higher than expected, it cannot be avoided that the diagnostic device stops functioning before detecting the deterioration.

  The present invention has been made to solve the above-described problems in the prior art, and notifies the repair information of the power supply unit of the CATV device by monitoring the actual operating state of the electrolytic capacitor. An object of the present invention is to provide a repair information notification device capable of performing the above.

  In order to achieve the above object, a repair information notification device according to the present invention removes a direct current component from a voltage charged and discharged by an electrolytic capacitor that smoothes a direct current pulsation included in a conversion circuit that converts alternating current into direct current. Proportional to the voltage of the pulsating voltage signal that generates a pulsating voltage signal, a high-frequency component removing unit that removes a high frequency higher than four times the frequency of the alternating current from the pulsating voltage signal, and the voltage of the pulsating voltage signal from which the high frequency has been removed A voltage signal generation unit that generates a DC voltage signal, a threshold signal generation unit that generates at least one predetermined threshold signal, and a repair information when the voltage signal becomes larger than the threshold signal. A repair information notification unit is included. With such a configuration, when the performance of the electrolytic capacitor is deteriorated, the repair information can be notified promptly.

  Further, in the repair information notification device according to the present invention, the threshold signal generation unit generates a first threshold signal and a second threshold signal larger than the first threshold signal, and the repair information notification unit When the voltage signal becomes larger than the first threshold signal, the first repair information that prompts replacement of the electrolytic capacitor is notified, and when the voltage signal becomes larger than the second threshold signal. The second repair information for stopping the operation of the conversion circuit is notified. With this configuration, the operation of the conversion circuit can be automatically stopped when the performance of the electrolytic capacitor is deteriorated.

  The repair information notification device according to the present invention can notify the repair information of the power supply unit of the CATV device by monitoring the pulsation voltage included in the charge / discharge voltage of the electrolytic capacitor.

  Hereinafter, the best mode for carrying out the present invention will be described. As shown in FIG. 1, the repair information notification device 1 according to the present invention includes a pulsation voltage signal generation unit 11 (a voltage charged and discharged by an electrolytic capacitor that smoothes DC pulsation included in a conversion circuit that converts AC to DC). The DC component is removed from the pulsating voltage signal to generate a pulsating voltage signal), the high frequency component removing unit 12 (from the pulsating voltage signal, a frequency higher than four times the AC frequency is removed), and the voltage signal generating unit 13 (high frequency is removed. A DC voltage signal proportional to the voltage of the generated pulsation voltage signal), a threshold signal generation unit 14 (generates at least one predetermined threshold signal), and a repair information notification unit 15 (the voltage signal is a threshold value). The repair information is notified when the signal becomes larger than the signal).

  FIG. 2 is a circuit diagram showing an example of an embodiment of the present invention. The conversion circuit 2 includes a transformer 21 that steps down or boosts the AC voltage supplied from the commercial power supply 20 to a desired voltage, a diode bridge 22 that rectifies and converts the stepped-down or boosted AC into DC, and a smoothing circuit. (Consisting of an electrolytic capacitor 23 for smoothing the pulsation contained in the rectified direct current). In the present embodiment, the smoothing circuit is constituted by one electrolytic capacitor 23, but may be constituted by a plurality of electrolytic capacitors.

  The pulsating voltage signal generation unit 11 is configured by a capacitor 31 (for example, a porcelain capacitor) with relatively little change in capacitance.

  The high-frequency component removing unit 12 is a low-frequency pass filter, and FIG. 2 shows a passive type composed of a resistor 321 and a capacitor 322, but may be an active type using an operational amplifier. When the pulsation voltage signal is smaller than the size that can be detected by the diode detection circuit, an amplification circuit for amplifying the output of the low-frequency pass filter may be provided.

  The voltage signal generator 13 generates a DC voltage signal proportional to the voltage, effective voltage, or peak voltage of the pulsating voltage signal from which the high frequency component has been removed. When the voltage signal is an effective voltage proportional to the voltage of the pulsating voltage signal from which the high frequency component has been removed, the voltage signal generator 13 serves as a diode detection composed of a first diode 331 and a second diode 332. The circuit 33 can be applied. Further, when the voltage signal is a peak voltage proportional to the voltage of the pulsating voltage signal from which the high frequency component has been removed, a peak holding circuit can be applied as the voltage signal generation unit 13.

  The threshold signal generation unit 14 includes a variable voltage source (for example, a voltage regulator and a potentiometer), and includes a first threshold signal generation circuit 341 and a second threshold signal generation circuit 342.

  The repair information notification unit 15 includes a first comparator 351 and a second comparator 352 using an operational amplifier, and drives a light emitting diode 353 and a relay 354 that notify repair information.

  Next, the operation of the repair information notification apparatus 1 according to the present invention will be described. The porcelain capacitor 31 removes a direct current component included in the voltage charged and discharged by the electrolytic capacitor 23, and generates a pulsating voltage signal including only the pulsating voltage component.

  The low-frequency pass filter composed of the resistor 321 and the capacitor 322 removes a high-frequency component contained in the pulsation voltage signal, and is several times (for example, 4 times) the frequency of the commercial power supply (for example, 50 cycles). Only pulsating voltage signals having a frequency (for example, 200 cycles) or less are extracted.

  The diode detection circuit 33 rectifies the pulsating voltage signal from which the high frequency component has been removed, and generates a DC voltage signal proportional to the effective voltage of the pulsating voltage signal. The DC voltage signal becomes higher as the performance deterioration of the electrolytic capacitor 23 progresses, and the degree of deterioration of the electrolytic capacitor 23 can be determined by monitoring the DC voltage signal.

  The first threshold signal generation circuit 341 generates a first threshold voltage that is determined to have deteriorated to such an extent that the electrolytic capacitor 23 needs to be replaced. Then, the second threshold signal generation circuit 342 generates a second threshold voltage that is determined to be impossible for further operation.

  The first comparator 351 compares the DC voltage signal with the first threshold voltage generated by the first threshold signal generation circuit 341, and when the DC voltage signal becomes higher than the first threshold voltage, The light emitting diode 353 emits light and prompts a repairman to replace the electrolytic capacitor 23.

  The second comparator 352 compares the DC voltage signal with the second threshold voltage generated by the second threshold signal generation circuit 342, and when the DC voltage signal becomes higher than the second threshold voltage, The relay 354 is operated to cut off the power supply from the commercial power supply 20 to the conversion circuit 2.

  As described above, according to the repair information notification apparatus according to the present invention, it is possible to monitor the pulsation voltage included in the charge / discharge voltage of the electrolytic capacitor and notify the repair information of the power supply unit of the CATV device. It is also useful in the field of digital CATV.

It is a block diagram which shows the structure of the repair information alerting | reporting apparatus 1 which concerns on this invention. 1 is a circuit diagram of a repair information notification device 1 according to the present invention.

Explanation of symbols

1: Repair information notification device,
11: Pulsating voltage signal generator,
12: High frequency component removal unit,
13: Voltage signal generator,
14: Threshold signal generator,
15: Repair information notification unit,
2: Conversion circuit,
20: Commercial power supply
21: Transformer
22: Diode bridge,
23: Electrolytic capacitor,
31: capacitor
321: resistance,
322: Capacitor,
33: Diode detection circuit,
341: a first threshold signal generation circuit;
342: a second threshold signal generation circuit,
351: first comparator,
352: second comparator,
353: light emitting diode,
354: Relay,

Claims (2)

A pulsating voltage signal generating unit that generates a pulsating voltage signal by removing a DC component from a voltage charged and discharged by an electrolytic capacitor that smoothes DC pulsation included in a conversion circuit that converts AC to DC;
A high frequency component removing unit for removing a high frequency higher than four times the frequency of the alternating current from the pulsating voltage signal;
A voltage signal generator that generates a voltage signal proportional to the voltage of the pulsating voltage signal from which a high frequency has been removed;
A threshold signal generation unit that generates at least one predetermined threshold signal;
A repair information notifying device comprising a repair information notifying unit for notifying repair information when the voltage signal becomes larger than the threshold signal. The threshold signal generation unit generates a first threshold signal and a second threshold signal larger than the first threshold signal;
The repair information notification unit notifies first repair information that prompts replacement of the electrolytic capacitor when the voltage signal becomes larger than the first threshold signal, and the voltage signal is the second threshold signal. The repair information notification device according to claim 1, wherein the repair information notification device is configured to notify second repair information that stops the operation of the conversion circuit when the conversion circuit becomes larger.

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