JP2010108842A - Power-saving device for high pressure discharge lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reduced in size and low-cost electric power saving device in which electric power saving can be carried out, by keeping the illuminance of a high-pressure discharge lamp, such as, mercury lamp or sodium-vapor lamp constant. <P>SOLUTION: An input voltage from an alternate power source 14 is measured by a voltage measurement circuit 23, and a target electric power to be output to the high-pressure discharge lamp 12 is set with a setting circuit 24. Wave pattern processing data for making electric power that is predicted from the voltage entered descend to a target electric power is stored in the memory circuit 25, in advance, then the control circuit 26 reads out the wave pattern processing data, according to the measurement value on the input electric voltage from the memory circuit 25, and conduction timing of a triac 21 is controlled for electric power adjustment. A relay 28 is installed in a by-pass circuit 22 that detours the triac 21; and when a non-conduction of the discharge lamp 12 is detected by a conduction detection circuit 27, the by-pass circuit 22 is closed by the relay 28, and the power source voltage is supplied to the discharge lamp 12 and lighting failure is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power-saving device that reduces power consumption by maintaining a constant illuminance in a high-pressure discharge lamp such as a mercury lamp or a sodium lamp.

  2. Description of the Related Art Conventionally, an apparatus that saves power in a high-pressure discharge lamp using a power adjustment element is known. For example, the power saving device 51 shown in FIG. 5 includes a triac 53 that cuts the waveform of the voltage input from the AC power supply 52, a setting circuit 55 that sets the power saving rate of the high-pressure discharge lamp 54, and the actual power consumption of the discharge lamp 54. And a control circuit 57 that feedback-controls the triac 53 so that the measured value satisfies the power saving rate. As shown in FIG. 6, the power consumption of the discharge lamp 54 is always constant. It is configured to be able to save with the power saving rate. In FIG. 6, the hatched portion indicates the amount of power saved by the conventional constant rate power saving method.

Conventionally, there has been known an apparatus that saves an illumination load using a transformer. For example, Patent Document 1 describes a power saving device that reduces the power consumption of an illumination load by stepping down an input voltage from an AC power source by an inverter on the primary side of a transformer. Patent Document 2 describes a power saving device in which a chopper circuit for adjusting an input voltage is provided on the primary side of a transformer, and a voltage having a stable waveform is supplied to the lighting load from the secondary side of the transformer.
JP 2002-176774 A JP 2002-10645 A

  However, since the conventional power saving apparatus 51 always saves the power consumption of the high pressure discharge lamp 54 at a constant power saving rate, when the input voltage varies, the output voltage also varies at the same ratio. For this reason, there is a problem that the illuminance of the discharge lamp 54 becomes unstable, flickering tends to occur, and the life is shortened. In addition, when the input voltage drops rapidly, the output voltage may further drop and the discharge lamp 54 may not light up. In addition, since the triac 53 is driven by feedback control, there is a disadvantage that response delay is likely to occur.

  In addition, since the triac 53 is connected in series to the AC power supply 52, when a failure occurs due to a lightning surge or the like, the circuit remains open and the discharge lamp 54 is turned off. In particular, when a discharge lamp installed at a high place is turned off, maintenance such as tube replacement becomes very difficult. Since the conventional devices of Patent Documents 1 and 2 are equipped with an inverter and chopper circuit on the primary side of the transformer, the lighting state of the lighting load is stable, but the circuit is complicated and large, and the manufacturing cost is high. This is not suitable for use in which one power saving device is installed in one discharge lamp.

  Accordingly, a main object of the present invention is to provide a small and inexpensive power-saving device that can save power while keeping the illuminance of a high-pressure discharge lamp constant. Another object of the present invention is to provide a power-saving device that is easy to maintain and that can continue to light a high-pressure discharge lamp even when a power adjustment element or the like fails.

  In order to solve the above-described problems, a power saving device according to the present invention includes a voltage measuring circuit for measuring an input voltage from an AC power source and a high pressure discharge lamp in a device that uses a power adjustment element to save power consumption of the high pressure discharge lamp. A setting circuit for setting the target power to be output to the memory, a storage circuit for storing in advance a control amount for reducing the power predicted from the input voltage to the target power, and a storage circuit for storing the control amount according to the measured value of the input voltage And a control circuit for controlling the power adjustment element by reading from the power supply.

  In addition to the above configuration, the power saving device of the present invention includes a bypass circuit that bypasses the power adjustment element, a relay that opens and closes the bypass circuit, and a conduction detection circuit that detects the conduction state of the high-pressure discharge lamp. When the circuit detects non-conduction of the high pressure discharge lamp, the control circuit drives the relay to close the bypass circuit.

  According to the power saving device of the present invention, the target power is set, and the power adjustment element is controlled so that the power predicted from the input voltage is lowered to the target power. Therefore, even when the input voltage fluctuates, the discharge lamp has a constant value. Power can be output. Therefore, the illuminance of the high-pressure discharge lamp is kept constant, and there is an effect that power consumption can be reduced without causing flickering or non-lighting. In addition, since the control amount of the power adjustment element is stored in the storage circuit in advance, there is an advantage that the configuration of the control circuit is simplified, the responsiveness is improved, and the entire apparatus can be manufactured in a small size and at low cost.

  In addition, when the continuity detection circuit detects the non-conduction of the high pressure discharge lamp, the power supply voltage is supplied to the high pressure discharge lamp via the bypass circuit. The discharge lamp can be lit continuously, and there is an effect that maintenance becomes easy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram functionally showing the configuration of the power saving apparatus, and FIG. 2 is a flowchart showing the operation of the power saving apparatus. FIG. 3 is a voltage waveform diagram illustrating the operation of the triac that is a power adjustment element, and FIG. 4 is a power characteristic diagram illustrating a power saving result by the constant output power saving method.

  As shown in FIG. 1, the power saving device 11 of this embodiment includes a case 13 installed in the vicinity of a high-pressure discharge lamp 12 such as a mercury lamp or a sodium lamp (for example, inside the switchboard). On the outer surface of the case 13, two input terminals 15 connected to the AC power supply 14 and two output terminals 16 connected to the discharge lamp 12 are disposed. One output terminal 16 is connected to the discharge lamp 12 via a ballast 17.

  The case 13 is provided with a circuit board (not shown), and the main circuit 20 on the circuit board is provided with a triac 21 for adjusting the waveform of the voltage input from the AC power supply 14 and is bypassed to bypass the triac 21. A circuit 22 is connected. Further, on the circuit board, a voltage measurement circuit 23 that measures an input voltage from the AC power supply 14, a setting circuit 24 that sets a target power output to the high-pressure discharge lamp 12, and a control amount of the triac 21 are stored in advance. A storage circuit 25, a control circuit 26 that controls the triac 21 with a control amount read from the storage circuit 25, and a conduction detection circuit 27 that detects the conduction state of the discharge lamp 12 are provided.

  A b-contact type relay 28 that opens and closes the circuit 22 is provided on the bypass circuit 22. The setting circuit 24 is provided with a dial 29 for setting the target power at a ratio (for example, 60 to 100%) with respect to the rated power. The storage circuit 25 stores waveform processing data for reducing the power predicted from the input voltage to the target power as a control amount of the triac 21 in the form of a list table. The control circuit 26 reads out waveform processing data corresponding to the measurement value input from the voltage measurement circuit 23 from the storage circuit 25, and controls the conduction timing of the triac 21.

  Next, a power saving method of the high pressure discharge lamp 12 in the power saving device 11 having the above configuration will be described. In the flowchart shown in FIG. 2, first, when power is turned on to the input terminal 15 of the power saving device 11, the control circuit 26 is activated, and an activation process for preparing power saving control is performed (S1). In the starting process, the relay 28 is excited, the bypass circuit 22 is opened, a starting signal is output to the triac 21, the main circuit 20 is closed, and the power supply voltage is supplied to the discharge lamp 12. And it waits for several minutes until the discharge lamp 12 will be in a complete lighting state (S2).

  Next, the control circuit 26 reads the target power set by the dial 29 from the setting circuit 24 (S3), and inputs the current input voltage from the voltage measurement circuit 23 (S4). Subsequently, the waveform processing data corresponding to the measured value of the input voltage is extracted from the storage circuit 25, and the timing signal is output to the triac 21 (S5). Then, as illustrated in FIG. 3, the triac 21 is turned on at a specified timing, a part of the input voltage waveform (the part indicated by hatching) is cut every half cycle, the voltage is reduced to 0 V, and the cut width W The amount of power corresponding to is reduced (S6).

  Thereafter, the control circuit 26 confirms the conduction state of the discharge lamp 12 based on the signal input from the conduction detection circuit 27 (S7). When the continuity is confirmed, the process returns to the input voltage measurement process and the waveform process is continued (S4 to S6). When the continuity cannot be confirmed, it is determined that the main circuit 20 remains open due to the failure of the triac 21, the relay 28 is demagnetized, the bypass circuit 22 is closed, and the power supply voltage is supplied to the discharge lamp 12. Since the relay 28 is of the b contact type, the bypass circuit can be used even if the control circuit 26 becomes inoperable due to the failure of the triac 21 or the breakage of circuit components including the melting of a fuse (not shown). 22 can be securely closed.

According to the power saving device 11 of this embodiment, the following effects can be expected.
(A) Since the triac 21 is controlled so that the target power is set and the power predicted from the input voltage drops to the target power, as shown in FIG. 4, it is affected by fluctuations in the input voltage. And constant power (target power) can be supplied to the high-pressure discharge lamp 12 at all times.
(B) For this reason, the illuminance of the discharge lamp 12 can be kept constant, and power consumption can be reduced in a state without flickering or non-lighting.
(C) Moreover, since the fluctuation | variation of input voltage is suppressed and fixed electric power is supplied to the discharge lamp 12, the lifetime of the discharge lamp 12 becomes long.
(D) Since the triac 21 is controlled by constantly measuring the input voltage, the discharge lamp 12 can be lit in a stable state even when a sudden voltage drop occurs.

(E) Since the target power can be changed stepwise by operating the dial 29 of the setting circuit 24, efficient power saving according to the facility environment of the discharge lamp 12 can be performed.
(F) For example, in an installation environment where the power demand decreases in the evening, an unnecessarily high power supply voltage is supplied. However, the power consumption of the discharge lamp 12 is reduced by reducing the power input from the AC power supply 14 to the target power. Can be saved efficiently.
(G) In addition, as shown in FIG. 4, in an equipment environment where the input voltage tends to fluctuate in a range exceeding the power supply voltage (AC rated voltage), even if the target power is set to 100% of the rated voltage, the surplus power Can be cut to increase the power saving effect.

(H) Since the waveform processing data of the triac 21 is stored in the storage circuit 25 in advance, the configuration of the voltage measurement circuit 23 and the control circuit 26 can be simplified, and the responsiveness is enhanced by using a simple control program. You can also.
(I) For this reason, the power saving device 11 can be manufactured in a small size, at low cost, and with high functionality. For example, in a lighting facility in which one power saving device 11 is installed in one discharge lamp 12, economical power saving can be achieved. It can be carried out.
(J) Since the relay 28 opens the bypass circuit 22 and supplies the power supply voltage to the discharge lamp 12 when the continuity detection circuit 27 detects the non-conduction of the discharge lamp 12, a fail-safe is ensured when the triac 21 or the like fails. The discharge lamp 12 can be lit continuously.
(K) For this reason, in particular, in the discharge lamp 12 installed in a high place such as a road or a factory, the number of tube replacements can be reduced and the maintenance of the lighting equipment can be easily performed.

  The present invention is not limited to the above-described embodiment. For example, the discharge lamp 12 is installed at a high place by using a remote control device such as a wireless remote controller or a personal computer with the power saving device 11 having a communication function. In addition to ON / OFF, it is also possible to change the configuration of each part as appropriate without departing from the spirit of the present invention, such as setting the target voltage to be operated from a remote location. .

It is a block diagram of the power-saving apparatus which shows one Example of this invention. It is a flowchart which shows operation | movement of a power saving apparatus. It is a voltage waveform diagram which shows operation | movement of a triac. It is a power characteristic figure which shows the constant output power saving system of this invention. It is a block diagram which shows the conventional power saving apparatus. It is a power characteristic figure which shows the conventional constant rate power saving system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Power saving apparatus 12 High pressure discharge lamp 14 AC power supply 21 Triac 22 Bypass circuit 23 Voltage measurement circuit 24 Setting circuit 25 Memory circuit 26 Control circuit 27 Continuity detection circuit 28 Relay

Claims (2)

In a power saving device that uses a power adjustment element to reduce the power consumption of a high-pressure discharge lamp,
A voltage measurement circuit for measuring the input voltage from the AC power supply, a setting circuit for setting the target power output to the high-pressure discharge lamp, and a control amount for lowering the power predicted from the input voltage to the target power are stored in advance. A power-saving device comprising: a memory circuit; and a control circuit that reads a control amount corresponding to a measured value of an input voltage from the memory circuit and controls a power adjustment element.   A bypass circuit that bypasses the power adjustment element; a relay that opens and closes the bypass circuit; and a conduction detection circuit that detects a conduction state of the high-pressure discharge lamp, and the conduction detection circuit detects non-conduction of the high-pressure discharge lamp. 2. The power saving apparatus according to claim 1, wherein the control circuit drives a relay to close the bypass circuit.

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