CN101816219B - Method for determining operational parameters for a gas discharge lamp to be operated with electronic ballast and corresponding ballast - Google Patents

Abstract

The invention discloses a method for determining operational parameters for a gas discharge lamp to be operated with electronic ballast and corresponding ballast. In order to determine operational parameters of a gas discharge lamp (L) to be operated with an electronic ballast (V), the cold resistance (Tcold) and the hot resistance (Rhot) of a helix (W1) are determined at at least two different times during the preheating phase. During the preheating phase, the heating power or the heating current is kept constant or alternatively, a predetermined heating power or a predetermined heating current is set at the beginning of the preheating phase. Thus a split of the resistance values during the preheating phase is carried out. The differential resistance (Rdiff) is formed from the hot resistance (Rhot) and the cold resistance (Rcold) and is independent from the start temperature of the helix (W1). The differential resistance (Rdiff) is compared to stored reference values in order to set the operational parameters corresponding to the lamp type on the ballast (V).

Description

Method for determining operating parameters of gas discharge lamps and corresponding ballasts

technical field

The invention relates to a method for determining the operating parameters of a gas discharge lamp to be operated with an electronic ballast. the

Background technique

A method is known from EP1519638A1. In this known method, the voltage drop across the resistance of the primary side of the filament transformer is measured at two different times during the preheating phase. The two voltage values thus derived are compared with standard voltage values stored in memory to determine the type of lamp. the

It is known from EP1125477B1 to determine the filament resistance of a lamp in order to determine the type of lamp by comparison with a standard resistance value stored in a register. the

Contents of the invention

The task of the present invention is to find a solution to the above-mentioned problems. the

Proceeding from the known method (EP1519638A1) mentioned at the outset, the solution consists in the combination of the features stated in the characterizing part of claim 1 . the

The object underlying the present invention is to provide a simple method for identifying the type of lamp which increases the identification reliability compared to hitherto known methods. the

According to the present invention, accomplish this task by following method step sequence:

a) regulating the filament current flowing through at least one filament such that the filament current has a predetermined current intensity,

b) direct or indirect measurement of the filament voltage,

c) After the calculation of the filament resistance, if possible, the lamp type is determined from the measured filament voltage and by comparing the measured filament voltage or the calculated filament resistance with the corresponding standard value stored in a table for each lamp. the

The solution of the invention uses the principle of measuring the resistance especially during the preheating phase with the filament power kept constant or with the filament current kept constant, and now in order to determine the type of lamp a combination of hot and cold resistors is used difference (gap), instead of thermal resistance. the

However, it is sufficient to adjust a certain filament power or a certain filament current at the beginning of the warm-up phase. This can be achieved by specifying an appropriate operating frequency and an appropriate on-time or corresponding duty cycle. If the filament circuit is designed to have power source characteristics or current source characteristics, it can be guaranteed that the filament power or filament current within a certain window can be adjusted during the preheating stage, and the window remains within a certain value range. the

In the prior art, filament layouts or control methods with voltage source characteristic curves or voltage control are always employed, which are not very suitable for the method being operated here. the

The invention is based on the insight that the measurement of the filament resistance via the filament current and the filament voltage presupposes that the filament receives electrical power. The electrical power causes the filament to heat up. Because the filament is generally made of metal, its resistance increases with temperature. Filament temperature depends on the filament power supplied to the filament. This qualitatively means that the greater the supplied filament power, the greater the filament resistance. the

It is now assumed that the second lamp differs from the first lamp in such a way that the filament resistance of the second lamp is twice that of the first lamp. If a known (applied) filament voltage is now applied to the filament as hitherto for the filament resistance measurement, the filament power (P= ^U2 /2R) supplied to the filament of the second lamp is twice as high due to the filament resistance And only half of the filament power (P=U ² /R) supplied to the filament of the first lamp. As a result, the filament of the second type of lamp heats up much less than the first type of filament. That is, the resistance heating increase of the filament of the second-type lamp is weaker than the resistance heating increase of the filament of the first-type lamp. Therefore, the increase in resistance heating runs counter to the increase in the basic resistance of the filament, and as a result, the reliability of lamp type identification is reduced.

If the filament is now supplied with the specified (imposed) current according to the invention, and if the filament resistance is subsequently determined by means of a filament voltage measurement, the trend is reversed. In this case, the filament power (P=I ² 2R) supplied to the filament of the lamp of the second type is twice the power supplied to the filament of the lamp of the first type (P=I ² R), so that the second lamp The resistance heating increase of the filament of the lamp is stronger than the resistance heating increase of the filament of the first lamp. As a result, the increase in resistance heating reinforces the increase in the basic resistance of the filament, and as a result, the reliability of lamp type identification is considerably high.

In other words, this means that a filament with a high ohmic value has a higher resistance when using a current source than a filament with a low ohmic value, and thus determines greater heating. This results in a greater difference in resistance, which in turn leads to higher recognizability. the

In practice, it is difficult to implement a current source for filament heating. Therefore, the regulation of the filament current flowing through at least one filament with a defined current intensity is preferably carried out by regulating the filament current. the

According to a refinement of the method according to the invention, a further step can be added to the above-described method steps, namely: setting at least one operating parameter for the ascertained lamp type. the

Forming the resistance difference has the advantage that the influence of the starting temperature is eliminated when measuring the cold resistance. the

Developments of the method according to the invention are the subject-matter of the claims dependent on claim 1 . the

The invention also relates to a ballast for at least one gas discharge lamp with which the method according to the invention can be carried out. The ballast is characterized by the features of claims 12 and 13 . Developments are the subject-matter of the claims dependent on claims 12 and 13 . the

The invention also relates to a ballast for a gas discharge lamp, which operates according to the above-mentioned method of operation. The ballast has the following characteristics:

memory for a table in which the corresponding filament voltage or the corresponding filament resistance is recorded for each lamp and for a certain filament current intensity;

A current regulator for adjusting a predetermined filament current for at least one filament;

Measuring mechanism for the direct or indirect measurement of the voltage drop across a filament subject to a specified filament current;

An optional mechanism to calculate the filament resistance according to the ratio of the measured filament voltage and the adjusted filament current;

A comparator to determine the lamp type by comparing the measured filament voltage or calculated filament resistance with the corresponding value recorded in the table. the

To regulate the filament current, the current regulator can have a control element for the filament current. the

An improvement of the ballast can be such that means are provided for setting at least one operating parameter for the ascertained lamp type. the

The measuring mechanism may comprise a voltage divider connected in parallel with the filament, from which a signal corresponding to the voltage of the filament is derived. the

A measuring resistor connected in series with the filament, from which a measuring signal corresponding to the filament current is derived, can belong to the control element. the

Description of drawings

A plurality of embodiments of the present invention will be described below in conjunction with accompanying drawing, wherein:

Fig. 1 is the schematic circuit block diagram of ballast of the present invention;

Fig. 2 is a flow chart representing how to apply the inventive method in fact;

Figure 3 shows the filament resistance versus preheat time for three different lamp types, and also shows the three regions of variation of the resulting resistance difference for each of the three lamps;

Figure 4a shows the relationship between the filament resistance and the filament voltage at the time of the applied filament voltage;

Figure 4b shows the relationship between the filament resistance and the filament current when the filament current is applied;

Figure 5 shows a gas discharge lamp with a corresponding ballast;

FIG. 6 shows the specific design structure of the filament voltage generating block in FIG. 5 . the

Detailed ways

The ballast V shown in FIG. 1 is used to operate a gas discharge lamp L having two filaments W1 and W2. the

To generate the operating voltage for the lamp L, the mains voltage is rectified by the rectifier 1 and smoothed in a smoothing circuit. The inverter 3 thus generates an AC voltage, which is supplied to the series resonant circuit 4 . The voltage dropped across the capacitor of the series resonant circuit 4 is supplied to the lamp L as an operating voltage. the

A programming controller 14 connected to the bus determines the activation of the lamp L preheating phase. It sends a start signal to box 8. Block 8 generates filament power or filament current for filaments W1 and W2 of lamp L. FIG. Filament power or filament current remains constant during the warm-up phase. Filament power or filament current is supplied to the lamp L through a frame 6 which includes a mechanism for limiting the voltage of the filament. A limitation of the filament voltage is necessary in order, for example, to avoid lateral discharges between individual parts of the filament. The filament current flowing through the "cold" filament W2 produces a voltage drop across resistor R3, which is supplied to filament current measuring means 7. A voltage is also tapped off at the voltage dividers R1 and R2 , which is the magnitude of the filament voltage for the “cold” filament W2 , which is supplied to the filament voltage measuring device 9 . the

The measured values successively measured by the filament current measuring device 7 and the filament voltage measuring device 9 are entered into a memory 15 . The memory 15 is controlled by the programming controller 14 in such a way that the measured values of the filament current and the filament voltage at two successive points in time of the preheating phase are stored. The stored measured values of filament current and filament voltage are input from a memory 15 into a ratio generator 10 in which the cold resistance and hot resistance of the filament are calculated. These values are passed from the ratio generator 10 to the difference generator 11 where the resistance difference is calculated. the

The difference value generator 11 supplies the resistance difference to the judgment logic circuit 13, and the judgment logic circuit 13 corresponds to a memory 12 in such a way that stores a table of standard resistance differences. Judgment logic circuit 13 compares the resistance difference calculated in block 11 with the standard value in the table stored in memory 12, and judges the type of lamp L operated by ballast V. The determined lamp type is reported by the decision logic 13 to the operating parameter regulator 5, which, in addition to the operating parameters, is especially important if the type of lamp L is different from the lamp type previously operated with the ballast V. Adjust filament current or filament power. the

In connection with this, it should be pointed out that the individual blocks in FIG. 1 do not have to be realized by hardware. Instead, the functions of several blocks can also be realized by corresponding software in the processor. The block diagram in Figure 1 should only be used for better understanding. the

FIG. 2 shows the logical sequence of the individual method steps for determining the lamp type, ie the software is used to demonstrate the invention. This will be explained later. the

The illustration in FIG. 2 relates to the case where two lamps are operated in parallel with one ballast. But it is obviously also possible to work with only one lamp. the

At the beginning of the warm-up phase, the cold resistances Rcold1 and Rcold2 are measured for both lamps. Calculates the absolute value of the difference |Rdiff| from two measurements. There are then three cases. If |Rdiff| is smaller than the first criterion value Refl, this means that the two lamps are of the same kind. Then proceed as in "Case 1". the

If the difference |Rdiff| is greater than the first standard value Ref1 but smaller than the second standard value Ref2, this means that the two lamps have indeed worked, but not of the same class. In this case, follow the "case 2" path. the

It should be noted here that in certain events the step of identifying the lamp type by means of the filament resistance check can be skipped. Therefore, it is possible to start an accelerated lamp start with the data stored in the electronic ballast (operating parameters adjusted after the previous lamp start) without measurement in the following special cases:

Grid reset or emergency lighting operation. A grid reset is a temporary interruption of grid power supply or a temporary reduction in grid voltage, which causes a temporary disconnection and subsequent restart of the electronic ballast. This situation can be caused by a grid transition (caused by the grid supplier) or by a grid failure. Emergency lighting operation can be realized, for example, by switching on a (backup) DC supply voltage and AC supply voltage or switching to battery operation in the event of a mains voltage interruption. the

From now on, the path "Case 1" is continued, ie a further evaluation is carried out here with the lamp having the lower cold resistance Rcold1 or Rcold2. the

Obviously, when there is only one lamp, the flowchart is also followed in this respect. In this case, the splitting of the cold resistance into two paths is eliminated. The progression of the flow chart is precisely to be limited to lamps with a lower cooling resistance or to one filament of the only lamp present. the

Furthermore, it is now checked whether the resistance difference Rdiff is smaller than a predetermined substitute resistance value Rsub. This comparison should check whether the lamp has been replaced for inspection purposes by a so-called substitute resistor which does not exhibit a temperature-dependent resistance in the hot state. If this is the case, there is no difference between cold and hot resistors. Therefore, if the judgment result is "Yes", the resistance difference Rdiff is set equal to the thermal resistance Rhot. the

If the resistance difference Rdiff is greater than the substitute resistance value Rsub, ie if the difference between Rcold and Rhot is sufficiently large due to the use of one lamp, the decision is "No". the

The next step is to check whether the resistance difference Rdiff is smaller than the stored first resistance value "level 1". If the resistance difference Rdiff is smaller than this level 1, it is judged here that it is the first type of lamp. the

If the resistance difference Rdiff is between the above-mentioned level 1 and another higher level 2, it is judged to be the second type of lamp. the

If the resistance difference Rdiff is between level 2 and another level 3, it is determined that it is a third type of lamp. the

The terms "level 1", "level 2" and "level 3" will be described in detail below with reference to FIG. 3 . the

As long as the resistance difference Rdiff falls within the aforementioned constraints and the type of lamp can be determined from this, then the operating parameters set according to the type of lamp are followed. the

And if the range in which the resistance difference Rdiff falls is not found, the last stored value is used to continue processing. the

Figure 3 shows the filament resistance curves for three different lamps during the warm-up phase, which lasts up to 500 ms. the

If it is the first kind of filament, the cold resistance Rcold1 is x ₂ WW, and the filament resistance Rhot1 is y ₂ WW, where WW represents the unit of resistance value.

In the case of the filament of the second lamp, the cold resistance Rcold2 is x ₃ WW which increases to x ₅ WW the hot resistance Rhot2 during the preheating phase.

The filament of the third lamp initially has a cold resistance Rcold3 of x ₄ WW. Thermal resistor Rhot3 whose resistance increases to x ₁₁ WW during the warm-up phase.

It is discovered how the resistance value develops with heating. The prerequisite here is that the same filament power or the same filament current is supplied to the filaments during the preheating phase. the

If the resistance difference is now always formed from the hot resistance Rhot and the cold resistance Rcold, a resistance difference equal to y ₁ WW results for the first lamp. The resistance difference Rdiff2 of the second lamp is equal to x ₅ WW. The resistance difference for the third lamp is equal to x ₁₀ WW.

The separation of the thermal resistors Rhot1 , Rhot2 and Rhot3 allows variable ranges that differ from one another to be defined for the resistance differences Rdiff1 , Rdiff2 and Rdiff3 . The region of change is indicated by hatching. the

Reliable identification can be obtained in any case if the determined filament resistance difference of a lamp falls within one of the three areas indicated by dashed lines. the

But it turns out that if you work at the level of the three marks, you can satisfactorily determine the lamp type. The first level "Level 1" is equal to the cold resistance Rcold1 of the first type of lamp. The second level "Level 2" is equal to the thermal resistance Rhot2 of the second lamp. The third level "Level 3" is located at a considerable distance above the thermal resistor Rhot3 of the third type of lamp. the

With the distance arrows marked on the right side of the illustration, the determination range for the relevant lamp type is indicated by a dashed line beyond the undefined lower area to the next level. the

The identification area emphasized by the shaded area is not strictly necessary, but is chosen randomly. Importantly, the shaded area (ie the area of change in the difference in resistance) allows for a more reliable identification of the lamp type. the

Figure 4a shows the dependence of the filament resistance Rw on the filament voltage Uw. Consider two filaments, one with filament resistance R ₁ and the other with filament resistance R2. The filament resistance R2 is twice the filament resistance _R1 . If the filament resistance R ₁ is set as R, then R ₂ =2R. Filaments are usually made of metal. The electrical resistance of metals increases with temperature. The two filaments form a line parallel to the abscissa, which is indicated by a dotted line, without taking into account the increase in resistance heating. If the increase in resistance heating is considered, the resistance of the two filaments increases as the filament voltage increases. The higher the filament power P supplied to the filament, the higher the corresponding increase in resistance heating. For a filament with a basic resistance R ₁ , the supplied filament power is P ₁ =U ² _W /R at the applied filament voltage. For a filament having a basic resistance R ₂ , the supplied filament power at the applied filament voltage is P ₂ =U ² _W /2R. That is, the filament power P2 supplied to the filament with the basic resistance _R2 is only _half of the filament power _P1 supplied to the filament with the basic resistance _R1 . As a result, the resistance of a filament with basic resistance _R2 increases less with increasing filament voltage _Uw than the resistance of a filament with basic resistance _R1 . The two curves approach each other with increasing filament voltage _Uw . As a result, the distinction between two lamps with different filament resistances _R1 and _R2 becomes difficult due to increased resistance heating.

FIG. 4b shows the idea on which the invention is based, namely that instead of an applied filament voltage _Uw , an applied filament current Iw is used. In this case, if the filament power supplied to the filament with the basic resistance R ₂ is P ₂ =2RI ² _W , it is twice the filament power P1 =RI ² _W supplied to the filament with the basic resistance Ri. It has been found that the two curves diverge here, with the result that the ability to determine the type of lamp according to the resistance of the filament is improved as a result of the increased heating of the resistance.

The relationship of the filament resistance R _w to the filament voltage U _w or the filament current I _w shown in FIGS. 4 a and 4 b is ideally represented by a straight line. For simplicity, the influence of other parameters as supplied filament power was not considered.

If "applied filament voltage _Uw " is mentioned in connection with FIG. 4a, this means that a defined filament voltage is applied to the filament from a voltage source of low ohmic value, and the resulting filament current is then measured. The filament resistance _Rw is then derived from the product of the filament voltage and the filament current.

In connection with FIG. 4b the term "impressed filament current _Iw " means the following. Here too, a filament voltage is applied to the filament. However, this filament voltage is not predetermined, but is only used to set a defined filament current. The filament resistance _Rw is then obtained as a product of the predetermined and preregulated filament current and the filament voltage, which is required so that the filament current flows through the filament and must be measured for this purpose. In principle, the "external filament current I _w " can of course also be supplied by a voltage source of high ohmic value, but the implementation of this possibility entails practical difficulties. It is much simpler to adjust the filament current (in the case of varying filament voltage) in such a way that it is at the desired specified value.

Figure 5 shows a gas discharge lamp L connected to an electronic ballast V constructed according to the invention. The ballast V comprises a bridge rectifier 1 connected to the alternating current network, which rectifies the mains voltage and supplies it to a direct voltage intermediate circuit 2 . The intermediate circuit 2 is followed by a half-bridge inverter 3 comprising two alternatingly operating switches. Connected to this inverter 3 is a purely resonant circuit, which consists of a choke coil and capacitors. The lamp is connected in parallel with the capacitor. Circuit parts 1-4 are common and known in ballasts. the

The ballast should now be designed in such a way that different types of fluorescent lamps L can be operated with it. The difference between the various types lies not only in the external dimensions, but also in different operating parameters, such as lamp current, lamp voltage, filament voltage, filament current, preheating time, etc. It is common and known for ballasts to automatically identify the lamp type, to be precise by measuring the resistance of at least one of the two filaments of the fluorescent lamp L. However, certain types of filament resistors are in close proximity so that they are difficult to distinguish, and as described above in connection with Figure 4a, this is further made difficult by heating. The principle of controlled filament current is therefore used in such a ballast concerned, which will be described in conjunction with FIG. 4 b. the

Before the lamp type can be ascertained, the filaments of the lamp L must first be supplied with a defined, known filament current. This filament current is registered either in the box 5 representing the operating parameter regulator, or in the start-up program (or programming controller) 14, when a corresponding command is obtained from the center via the bus Usus , the controller is programmed to transmit the associated current value to box 5 . The transmitted setpoint value is supplied by the operating variable controller 5 to a filament current regulator 8 which in turn causes the filament voltage generator 6 to supply the two filaments W1 and W2 of the fluorescent lamp L with the corresponding filament voltage. The filament voltage applied to the lower filament W2 is extracted by a voltage divider composed of resistors R1 and R2 and supplied to the filament voltage measuring mechanism 9, and the filament voltage measuring mechanism 9 continues to transmit the measured filament voltage value to the ratio generator 10 . The filament current flowing through the filament W2 is measured in the form of a voltage drop via the resistor R3 and supplied to the filament current measuring device 7, which in turn reports the measured filament current value to the ratio generator 10 on the one hand and as The actual value is reported to the filament current regulator 8 . the

This forms an adjustment value and transmits this adjustment value to the filament voltage generator 6 , whereby the filament voltage is adjusted so that the filament current is equal to the nominal value supplied to the filament current regulator 5 . The ratio generator 10 calculates the filament resistance from the measured filament voltage value and the measured filament current value. The filament resistance is supplied to a comparator (decision logic) 13 which compares it with values stored in a table, which is stored in memory 12. The table has a corresponding filament resistance for each type of lamp to be operated with the ballast. This filament resistance is compared to the measured filament resistance. The comparator (decision logic) 13 then reports the ascertained lamp type to the operating variable controller 5 . The latter takes the relevant regulation on the ballast V. A representation of this is considered in FIG. 5 by the connection between the operating variable controller 5 and the inverter 3 . In this way, therefore, the cadence frequency and/or the cadence time of the two switches of the inverter can be influenced in order to adjust a certain operating parameter. the

It should be pointed out here that the ratio generator 10 itself is not necessary. Instead of storing in the memory 12 a table containing the correspondence between filament resistances and lamp types, it is also possible to write down a table which contains, for each lamp at a known pre-adjusted filament current, the corresponding filament Voltage. The filament voltage measuring means 9 must in this case report the determined filament voltage to the comparator (decision logic) 13 instead of the filament resistance. The reporting of the filament current measured by the filament current measuring device 7 in FIG. 5 to the ratio generator 10 is then omitted. the

FIG. 6 shows a specific way to realize the filament voltage generating mechanism 6 . It comprises a blocking converter comprising an electronic switch S, a resistor R4 and an induction coil formed by the primary winding of a filament transformer _TH . As DC voltage source, the bus voltage U _BUS applied to the bus is used. Instead of the bus voltage U _BUS , it is also possible to use the output voltage of the intermediate circuit 2 . The filament transformer _TH has two secondary windings, wherein each secondary winding is dedicated to a filament of the fluorescent lamp L. The AC voltage delivered by the filament transformer _TH will be rectified by diodes O1 and O2 and smoothed by capacitors C1 and C2. Apart from this, capacitors C1 and C2 also have the task of helping to eliminate radio interference.

Claims (18)

1. a method of determining the running parameter of the gaseous discharge lamp (L) that will operate with electric ballast (V), comprises the following steps:

A) at least one filament (Wl, W2) of preheating,

B) directly or indirectly measure filament voltage (U _w),

C) by comparing and measuring value and the standard value of storing, determine the value to be selected of a running parameter,

It is characterized in that,

Dl), in measuring process, the filament wattage that keeps heater current or supply with filament between two moment is stablized constant,

E) filament voltage (U _w) directly or indirectly measure and carry out at least two different moment,

F) the additional heater current of measuring,

G) in first moment, according to the measured value of filament voltage and heater current, calculate cold resistance (Rcold), second, calculate thermal resistance (Rhot) constantly,

H) according to thermal resistance (Rhot) and cold resistance (Rcold), calculate resistance difference (Rdiff), and

I) adopt at a h) resistance difference (Rdiff) obtained as will with the measured value of stored standard value comparison, to determine running parameter.

2. according to the method for claim 1, it is characterized in that, step (dl) realizes by adjusting heater current or filament wattage.

3. according to the method for claim 1, it is characterized in that, there are following steps:

I) for determined lamp type, adjust at least one running parameter.

4. according to the method for claim 1, it is characterized in that, storage standard value in groups, this standard value is in groups applicable to a plurality of predetermined preheat value.

5. according to the method for claim 1, it is characterized in that, storage standard value in groups, this standard value is in groups applicable to heater current, filament voltage or filament wattage.

6. according to the method for claim 1, it is characterized in that, if control multi-lamp (Ll, L2) with this ballast (V), check whether same type of these lamps.

7. according to the method for claim 6, it is characterized in that, in order to carry out the inspection whether identical to lamp type, form each two lamp (Ll, L2) cold resistance (Rcold) differs from and compares with the first standard value (Rrefl), when this difference is greater than the first standard value, is defined as not identical.

8. according to the method for claim 1, it is characterized in that, if control multi-lamp (Ll, L2) with this ballast (V), whether inspecting lamp there is filament breaking, measures its filament voltage and falls to calculate filament resistance (Rcold, Rhot).

9. method according to Claim 8, is characterized in that, in order to carry out the inspection to filament breaking, form each two lamp (Ll, L2) cold resistance (Rcold) differs from and compares with the second standard value (Rref2), when this difference is greater than the second fiducial value, is defined as filament breaking.

10. according to the method for claim 9, it is characterized in that, if operating multi-lamp (Ll with ballast (V), L2) time, by a common resistance (R3), realize the measurement of heater current, in diagnosis, find filament (W1b, W2b) when fracture, filament resistance (Rcold, the Rhot) value calculating accounts for the flow through ratio of filament sum of measuring resistance (R3) of its heater current according to the filament number that ruptures and is reduced.

11. 1 kinds of ballasts (V) at least one small cup with the gaseous discharge lamp (L) of two filaments (Wl, W2), have:

For generation of stablizing constant heater current or stablizing constant filament wattage and at least one in two filaments (Wl, W2) applied to the mechanism (8) that this is stablized constant heater current or stablizes constant filament wattage,

Directly or indirectly measure the measuring mechanism (9) of the voltage drop on filament (Wl, W2),

Heater current measuring mechanism (7),

Memory (15), stores the measured value of the voltage drop on this filament (Wl, W2) and the measured value of the heater current of the filament of flowing through,

Storing value by the heater current by for measuring and for the mechanism of recently calculating filament resistance (Rcold, Rhot) (10) of the storing value of the voltage drop on the filament (Wl, W2) of measuring,

For the memory (12) of a table, in this table, for each lamp type and for heater current intensity or the filament wattage of regulation, record standard resistor difference, and

By the filament resistance (Rcold, Rhot) calculating and the decision mechanism that relatively judges lamp type (12) that is recorded in the standard resistor difference in memory (12).

12. 1 kinds of ballasts (V) at least one small cup with the gaseous discharge lamp (L) of two filaments (Wl, W2), have:

For generation of stablizing constant heater current or stablizing constant filament wattage and at least one in two filaments (Wl, W2) applied to the mechanism (8) that this is stablized constant heater current or stablizes constant filament wattage,

For directly or indirectly measuring the measuring mechanism (9) of the voltage drop on this filament (Wl, W2),

Program setting controlling organization (14), it determines that two in warm-up phase are not measured the voltage drop on filament (Wl, W2) in the same time at described two not in the same time,

Heater current measuring mechanism (7),

Be used for storing the measured value of the voltage drop on filament (Wl, W2) and at the flow through memory (15) of measured value of heater current of this filament of two moment being set by this program setting controlling organization (14),

According to the storing value of the heater current of measuring and the filament (Wl measuring, the ratio of the storing value of the voltage drop W2) and calculate the filament resistance (Rcold in two moment being set by this program setting controlling organization (14), Rhot) mechanism (10)

For the memory (12) of a table, in this table, for each lamp type and for heater current intensity or the filament wattage of regulation, record standard resistor difference, and

Be used for by the decision mechanism that relatively judges lamp type (12) of the resistance difference (Rdiff) calculating and the standard resistor difference of recording at memory (12).

13. according to the ballast of claim 11 or 12, it is characterized in that, has for adjusting the mechanism (5) at least one running parameter of obtained lamp type.

14. according to the ballast of claim 11 or 12, it is characterized in that, should comprise the adjuster (8) for heater current or filament wattage for generation of the mechanism (8) that stablizes constant heater current or stablize constant filament wattage.

15. according to the ballast of claim 11 or 12, it is characterized in that, for directly or indirectly measuring, accept predetermined constant heater current or the predetermined filament (Wl that stablizes constant filament wattage of stablizing, the measuring mechanism of the voltage drop W2) (9) comprises the voltage divider (R1, R2) with filament parallel.

16. according to the ballast of claim 11 or 12, it is characterized in that, and in order to measure heater current (8), measuring resistance (R3) and filament (Wl, W2) series connection, the voltage drop on this measuring resistance is used as the measured value of heater current.

17. according to the ballast of claim 11 or 12, it is characterized in that, if with two of this ballast operation or more lamps (Ll, L2), the heater current that makes to flow through each filament (W1b, W2b) of every lamp flows through measuring resistance (R3).

18. according to the ballast of claim 11 or 12, it is characterized in that, when filament (W1b is found in diagnosis, while W2b) rupturing, filament resistance (Rcold, the Rhot) value that You Gai mechanism (10) calculates accounts for the flow through ratio of filament sum of measuring resistance (R3) of its heater current according to fracture filament and is reduced.

Images