JPS602760B2 - How to combine ballasts in lighting circuits for high-pressure discharge lamps - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention reduces the difference between the input current at the time of starting and the input current at the time of stabilization of a branch circuit mainly used for lighting by combining ballasts for high pressure discharge lamps with different circuit configurations. The present invention relates to a method that enables economical branch circuit design.

Conventionally, when lighting a high-pressure discharge lamp, such as a 200V 400W mercury lamp, a ballast having a circuit configuration as shown in FIGS. 2 to 6 was mainly used.

Note: In these figures, A indicates input current and t indicates time. However, in the slow phase low power factor ballast shown in Figure 2a, the starting input current is 1.76 times the stable current as shown in Figure 2b, and in the slow phase high power factor ballast shown in Figure 3a, the starting current is 1.76 times the stable current. A very large current flows, 1.7 times as large. For this reason, branch circuits are designed with a large amount of current, which leaves too much margin when stable, resulting in an uneconomical design. In order to improve the above-mentioned drawbacks, low starting current type ballasts such as the one shown in Shigeru A came to be used.

This ballast is a slow-phase high power factor type ballast shown in Figure 3a, and is composed of a circuit in which one or two capacitors 2, which are connected in parallel with the power supply, are connected in parallel with the power supply. . In this kind of circuit configuration, if the lamp goes out, a large phase-advanced current will flow as the input current, or if the power supply contains harmonics, a very large phase-advanced current will flow. There are drawbacks such as the possibility of tripping the breaker. On the other hand, as in the case of the constant power single-lamp ballast shown in Figure 5a and the constant power double-lamp ballast shown in Figure 6a, the input current at startup is smaller than when stable (0.48 to 0.62 2) There is also a stabilizer.

However, as shown in Table 1, these ballasts have a price of 2 if the price of a slow phase low power factor ballast is 1, and a constant power ballast for one lamp is 2.
．． 5, which is very expensive. In addition, the price ratio of the constant power type for two lamps shown in Figure 6a is 3.16 (1.58 for one lamp), which is higher than the ballast shown in Figures 4 and 5. Although it is not expensive in terms of price, it has the disadvantage that if one lamp fails to turn on due to a defect in the circuit, the other lamp will also malfunction, making this ballast difficult to use depending on the application. In addition, the phase-advanced low power factor type ballast shown in Figure 7a does not have much difference in input current during starting and during stabilization when using this ballast alone, but it is expensive and does not provide much benefit even when used alone. It is a vessel.

As shown in Table 1 for 400W and 200V in FIGS. 2 to 7, conventional mercury lamp ballasts have the above-mentioned drawbacks, making it difficult to design an economical branch circuit for lighting circuits.

*The present invention provides a method that enables an economical branch circuit design by combining ballasts with different circuit configurations and using them in the same branch to overcome the above-mentioned drawbacks.

Specifically, we are considering combining a phase-leading low power factor type ballast shown in Fig. 7, which has never been used alone, with a lagging phase low power factor type ballast shown in Fig. 2. Features.

Table 2 shows various characteristics when the present invention is applied to a 200V, 400W mercury lamp ballast and the price ratio to a general type low power factor type ballast. An example of a combination of ballasts, i.e., phase advance low power factor type ballast 1
When one general type low power factor type ballast is combined with the stand (
Fig. 8) and Fig. 9 show the respective input current strokes when two general low power factor ballasts are combined (Fig. 9).

Table 2 Note: Values in parentheses represent per lamp.As shown in Table 2, when using a combination of a phase-leading low power factor type ballast and a slow-phase constant power factor type ballast, starting The input current during operation is as low as 0.5 to 1.14 times when it is stable, and the circuit power factor is a combination of 2 lagging phase low power factor type ballasts and 1 phase advancing low power factor type ballast for 3 lights. It is also the kudzu power rate.

The price is also 3.2 when a general type low power factor type ballast is set as 1, and a combination of one phase advance low power factor type ballast and one general type low power factor type ballast is used for two lights. , and phase-advanced low power factor type ballast 1
If the base and two general low power factor ballasts are combined for three lamps, the cost will be 4.2, and the ballast price per lamp will be 1.4 for the former and 1.4 for the latter, as shown in Figure 4. It is 11 to 12% cheaper than the low starting current type ballast shown in . This utilizes the phase difference between the slow phase circuit and the phase advance circuit, and as shown in Figure 1, the power factor of both circuits is approximately 0. In the case of a combination of one unit at a time, the power factor is 0. The result is spotty, which is equivalent to the conventional flickerless type.

However, when there are three or more units, the combination shown in FIG. 1 is the cheapest when the power factor is set to 0.9 or more. In addition, in the case of a combination with a circuit power factor of 0.9 or more, the input current at startup can be suppressed to within 1.2 times the stable state by combining the opposite vectors, similar to the combination of the input current when the lamp is stable. I can do it. Table 3 shows a list of performance and price when each ballast is used in a lighting circuit for 1 to 10 200V 400W mercury lamps. As is clear from Table 3, in the combination example of the present invention, the input current value at the time of starting is slightly lower than that of the low starting current type ballast, and the price is about 20% cheaper. Table 3 ■ Input current at starting @ Input current at stable time ■ Price ratio * 400W
For 200V, the present invention has many advantages in addition to the above-mentioned input force characteristics at startup and price.

In other words, since it does not have a capacitor connected in parallel with the power supply, even if it is used with a power supply that contains harmonics, the input current will increase only by 4.5 cm, and even if the lamp malfunctions, unnecessary current will flow. Also, there is no inrush current of the capacitor at switch-on. Since several light sources (lamps) with different statuses are added, a frizzless effect is also exhibited. Furthermore, in the above embodiments, a 200V, 400W mercury lamp was described, but the method of the present invention may be applied to other rated mercury lamps, high pressure sodium lamps, or metal halide lamps.

As described above, the present invention can exhibit extremely excellent effects in terms of cost and characteristics by appropriately combining a slow phase low power factor type ballast and a phase advanced low power factor type ballast, and provides great benefits to the user. This is an extremely practical invention that can be provided.

[Brief explanation of drawings]

Fig. 1 is a vector diagram for determining the combination of the present invention, Figs. Figure 3 shows a general type high power factor type ballast, Figure 4 shows a low starting turtle flow type ballast, and Figure 5 shows a constant power type ballast for one lamp. 6th
The figure shows a constant power type ballast for two lamps, and Figure 7 shows one using a phase advance low power factor type ballast. Furthermore, b in Figs. 2 to 7 is an input current stroke diagram corresponding to the lighting circuit configuration shown in a, and Fig. 8 is a diagram showing a phase advance low power factor type ballast according to the present invention and a general type low power factor type ballast. Figure 9 shows the input current stroke diagram when one phase advance low power factor type ballast and two general type low power factor type ballasts are combined. It is an input current journey diagram. In addition,
In each figure, the same reference numerals indicate the same or corresponding parts. In the figure, 1 is a choke coil, 2 is a capacitor, and 3 is a transformer. Figure 2 Figure 3 Figure 4 Figure 1 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] 1 Ratio of use of lagging phase low power factor type ballast (A) and phase leading low power factor type ballast (B) in one branch circuit mainly for lighting equipment (A
/B) is 1<A/B≦3, the circuit power factor is high power factor,
A method for combining a ballast for a lighting circuit for a high-pressure discharge lamp, characterized in that the input current at the time of starting is set to within 120% of the input current at the time of stability.