DE102010063992A1 - Evaluation of the supply voltage of operating devices for lamps - Google Patents

Abstract

The invention relates to ballast, operating device for lamps. with separate measuring circuits (M1, M2) to break down a rectified voltage (Vmains) into a positive and a negative voltage component, the voltage (Vmains) z. B. as AC voltage, as a pulsating DC voltage or as a constant DC voltage, an evaluation circuit, which evaluates the voltage components (Vac / dc) of the two measuring circuits (M1, M2) to identify the type of voltage present, and an analysis circuit, which via a AD converter analyzes the voltage components (Vac / dc), and calculates further characteristics of the voltage (Vmains), e.g. B. the presence of an overvoltage, in particular by polarity reversal, an amplitude value, an average value of the voltage (Vmains) and / or information modulated onto the voltage.

Description

The invention relates generally to the field of control gear for lamps (gas discharge lamps, halogen, LED, OLED) and in particular the evaluation of the supply voltage of these operating devices.

The basis of this "evaluation" is always a branch fed from the supply voltage, which is in addition to the branch by means of which the lighting means are supplied with power.

From the EP 0 939 476 B1 is a device with a bridge rectifier, which is turned on in a first state of an emergency operation in a safety power supply branch. The device contains switching elements that connect certain intended only for emergency lights only with the voltage applied to the input supply voltage when the supply voltage is a constant or only positive half-waves existing DC voltage, but not if the supply voltage is an AC voltage. A precise differentiation of different supply voltages in the DC and AC voltage range is not possible.

Next is from the DE 10 2007 040 555 A1 a method and a circuit for identifying the type of voltage V _{mains is} known, which is present in two of three different temporal voltage waveforms. The circuit includes a bridge rectifier, from which two measuring circuits emanate, with positive current components flowing in one measuring circuit and negative current components in the other. The identification of the type of applied voltage is performed by an evaluation circuit part.

The invention has for its object to provide an advantageous evaluation of the supply voltage in addition to the forwarding of the supply voltage to the light sources.

• – Erfassung wenigstens eines Parameters der Versorgungsspannung (Polarität, AC/DC-Erkennung, Amplitude, Frequenz...),
• – Erfassung von eingehenden Signalen, die die Versorgungsspannung als Träger verwenden, und/oder
• – Bereitstellung einer Spannungsversorgung.

By "evaluation" according to the invention is meant one or more of the following aspects:

• Detecting at least one parameter of the supply voltage (polarity, AC / DC detection, amplitude, frequency...),
• - Detecting incoming signals that use the supply voltage as a carrier, and / or
• - Provision of a power supply.

The object is solved by the features of the independent claims. The dependent claims further form the central idea of the invention in a particularly advantageous manner.

The invention goes from the DE 10 2007 040 555 A1 and develops this further to the effect that an analysis circuit is provided which the currents of the two measuring circuits from the DE 10 2007 040 555 A1 For example, to further evaluate and analyze the desired parameters of the applied voltage.

BRIEF DESCRIPTION OF THE INVENTION In a first aspect, the invention provides a ballast with separate measuring circuits for decomposing a voltage rectified by a rectifying means into a positive and a negative voltage component, the voltage being e.g. As an AC voltage, as a pulsating DC voltage or constant DC voltage may be present, an evaluation circuit which evaluates the voltage components of the two measuring circuits for identifying the type of applied voltage, and an analysis circuit which analyzes the voltage components via an AD converter, and further features the voltage is calculated, z. Example, an overvoltage, in particular by reverse polarity, an amplitude value, an average value of the voltage and / or an information modulated on the voltage.

The analysis circuit may determine a frequency of the voltage or a voltage value.

The AD converter may be adaptive and may dictate a time window for measuring the voltage components based on a frequency of the voltage.

The analysis circuit may measure the voltage components over a period of the voltage.

The analysis circuit may use different factors depending on the detected voltage for the calculation.

The factors may depend on whether clamping is provided.

The analysis circuit can determine the zero crossings of the voltage.

At least one threshold value may be provided in the analysis circuit and the analysis circuit may detect the applied voltage based on its behavior with respect to the at least one threshold value.

In a further aspect, the invention provides a circuit for analyzing a voltage, in particular the supply voltage supplied to a ballast ready in at least two of at least three different temporal forms such. B. as AC voltage, as a pulsating DC voltage or as a constant DC voltage, with rectification means for the present voltage, wherein the rectifying means are designed so that they decompose the present voltage into a positive and a negative voltage component, that each of the two voltage components is a voltage source forms a separate measuring circuit, and an evaluation circuit, which evaluates the currents of the two measuring circuits for identifying the type of applied voltage, the circuit comprises an analysis circuit which analyzes the voltage components via an AD converter, and calculates further characteristics of the voltage, for , Example, an overvoltage, in particular by reverse polarity, an amplitude value, an average value of the voltage and / or an information modulated on the voltage.

In a still further aspect, the invention provides a method for analyzing a stress that is at least in two of at least three different time courses, such as in at least B. as AC voltage, as a pulsating DC voltage or as a constant DC voltage, wherein the present voltage is rectified, such that it is decomposed into a positive and a negative voltage component, that the two voltage components are used as voltage sources for two measuring circuits, and that the currents in the two measuring circuits are evaluated to identify the type of voltage present, an analyzing circuit analyzing the voltage components via an AD converter, and calculating further characteristics of the voltage, e.g. Example, an overvoltage, in particular by reverse polarity, an amplitude value, an average value of the voltage and / or an information modulated on the voltage.

Further aspects of the invention will be described below with reference to the drawings.

Brief description of the drawings

1 shows a circuit diagram of a circuit according to the invention.

2 shows voltage curves at individual points of the circuit at the different supply voltage types.

3 shows a circuit diagram of a circuit according to the invention.

4 illustrates various factors for calculations for voltage V _mains .

5 illustrates factors for calculating V _mains when jammed.

6 - 10 show voltage curves at different points of the circuit at different supply voltage types.

Detailed description of the invention

First, the 1 be described in the prior art, from which the invention proceeds.

The evaluated supply voltage V _mains is applied to the input of the circuit, which is part of an electronic ballast (ECG). It can be present as an alternating voltage with successive half-waves of different polarity, as a pulsating direct voltage with successive half-waves of the same polarity, as a constant direct voltage (positive / negative) or as a zero voltage (no voltage).

Based on the circuit 1 I will first explain how the type of tension can be identified. The voltage passes first a noise filter, which consists of two symmetrical chokes / inductors L1 and L2 and a capacitor C1, which connects the parallel chokes. The output of the noise filter is applied to terminals 1 and 2 of the one diagonal of a bridge rectifier B, which is formed by four bridge diodes D1, D2, D3 and D4. A terminal 4 of the other diagonal of the bridge rectifier B is grounded M. The other terminal 3 of the other bridge diagonal leads a voltage that is further processed, it does not matter how the processing is done here.

For the following description and the corresponding illustrations in the individual figures, it is assumed that the supply voltage V _{mains present} at the input of the noise filter does not undergo any change due to the noise filter, ie that the supply voltage V _{mains is} also applied to the terminals 1 and 2 of the bridge rectifier B is applied.

The circuit contains two measuring circuits M1 and M2. The first measuring circuit M1 is shown in dotted lines; the second measuring circuit M2 is shown in dashed lines.

The current of the first measuring circuit M1 starts from the terminal 1 of the bridge rectifier B and continues to flow through a separate Resistor R1, a two resistors common resistor R3, a common also two circuits measuring resistor R4, via ground M, through the bridge diode D3 to the terminal 2 of the bridge rectifier.

The current of the second measuring circuit M2 starts from the terminal 2 of the bridge rectifier B and continues through the separate resistor R2, the common resistor R3, the common measuring resistor R4, via ground M, through the bridge diode D4 to the terminal 1 of the bridge rectifier B.

At the terminals 1 and 2 of a bridge diagonal two partial voltages of different polarity arise, which form the voltage sources for the two measuring circuits M1 and M2 and are the cause of the flow of currents in the two measuring circuits.

Current flows in measuring circuit M1 as long as terminal 1 is positive and terminal 2 is negative. Conversely, current flows in the measuring circuit M2 when the terminal 2 is positive and the terminal 1 is negative.

If V _{mains is} an AC voltage with alternating positive and negative mains half-waves, the result is that a current flows through the measuring circuit M1 during the positive half-cycle while a current flows through the measuring circuit M2 during the negative half-cycle. However, both currents flow - as the arrows indicate - through the series resistor R3 and the measuring resistor R4 in the same direction. In order to distinguish the currents flowing through the measuring resistor R4 according to whether they belong to the measuring circuit M1 or to the measuring circuit M2, the resistance values of the separate resistors R1 and R2 are chosen differently. As a result, the currents of the two measuring circuits M1 and M2 are different, because the resistor R1 belongs only to the measuring circuit M1 and the resistor R2 only to the measuring circuit M2.

The voltage drop across the measuring resistor R4 is evaluated by an evaluation circuit comprising a suppressor capacitor C2 and two comparators K1 and K2. The voltage drop across the measuring resistor R4 is denoted by V _{ac / dc} . The comparator 1 On the one hand, the measuring voltage dropping across R4 is supplied, and on the other hand the voltage V _{ref / high} as the threshold value. The comparator K2 is likewise supplied with the measuring voltage V _{ac / dc} which drops across the measuring resistor R4 and, to this end, the voltage V _{ref / low} as the threshold value.

For the further considerations, it is assumed that the separate resistor R2 is greater than the separate resistor R1. This means that the current in the first measuring circuit M1 is greater than the current in the second measuring circuit M2.

In 2 In the upper part, different cases are shown for types of supply voltage V _mains . The lower part shows the voltage drop across the measuring resistor R4.

In section A of 2 (above) the supply voltage V _mains consists of positive and negative half-waves. At the measuring resistor R4 thereby drops a voltage consisting of positive half-waves, alternately from those with higher and those with lower amplitude. The higher amplitude half-waves are indicative of the current in the second measurement circuit M1, while the lower amplitude half-waves are indicative of the current in the first measurement circuit M2. This section A of 2 shown below.

The evaluation of the voltage curve in the two comparators K1 and K2 takes place in that the comparator K2 with the lower threshold value V _{ref / low} produces at its output a pulse train which corresponds to that of the mains half-waves. In contrast, at the output of the comparator K1 with the higher threshold value V _{ref / high,} only the half-waves with the higher amplitude can cause a reaction, so that only every second half wave, and that with the higher amplitude, produces an output pulse. If z. B. the supply voltage V _{mains is} an ordinary mains voltage with the frequency of 50 Hz, so occur at the output of the comparator K1 pulses at the pulse repetition frequency of z. B. 50 Hz, while at the output of the comparator K2 pulses with the pulse repetition frequency of z. B. 100 Hz occur. This combination thus makes it possible to identify an ordinary mains voltage as a supply voltage.

Section B of 2 (top) now shows a supply voltage V _mains , which consists only of positive mains half-waves. Such a supply voltage is generated for example by a bridge rectifier. The only positive power half-waves cause only in the measuring circuit M1 with the larger resistor R1, a current flows, due to both half-waves. In the measuring circuit M2, however, no current flows. The measuring voltage drop across the measuring resistor R4 is shown in section B of 2 shown below. At the output of both comparators K1 and K2 then z. B. pulses with a pulse repetition frequency of 100 Hz. This stress pattern is indicative of those in Section B of 2 (shown above) supply voltage V _mains .

In Section C of 2 (top), the case is shown that the supply voltage V _mains only consists of negative network half-waves. Section C of 2 (bottom) shows the measuring voltage V _{ac / dc} , which drops across the measuring resistor R4. This consists of only positive half waves, all of which have a low amplitude, which is determined by the larger resistor R2. At the output of the comparator K1 with the higher threshold value V _{ref / high} then no voltage occurs, while the output voltage of the comparator K 2 with the lower threshold value V _{ref / low} of pulses with the pulse repetition frequency of z. B. 100 Hz. This stress pattern is characteristic of the conditions in Section C of 2 (shown above) supply voltage V _mains .

According to section D of 2 (above), the supply voltage V _mains consists of a constant positive DC voltage. According to section D of 2 (bottom) this results in a constant voltage drop V _{ac / dc} at the measuring resistor R4. This is higher than the two threshold values V _{ref / low} and V _{ref / high} for the comparators K1 and K2. Accordingly, a constant DC voltage occurs at the output of both comparators. The two DC voltages are the same. This voltage pattern is therefore characteristic for the in section D of 2 (shown above) supply voltage V _mains .

Section E of 2 (top) shows the case that the supply voltage is a negative DC constant voltage V _mains . This has according to Section E of 2 (bottom) to the measuring resistor R4 a voltage drop V _{ac / dc} result, which is also a constant DC voltage. This is lower than the higher threshold V _{ref / high} for the comparator K1, but higher than the lower threshold V _{ref / low} for the comparator K2. This has the consequence that at the output of the comparator K2 a constant DC voltage occurs, while no voltage occurs at the output of the comparator K1. This voltage pattern is therefore characteristic of those in Section E of 2 (shown above) supply voltage V _mains .

If V _{mains is} zero, this has the consequence that also at the measuring resistor R4 the voltage drop V _{ac / dc is} equal to zero. Accordingly, the voltage at the output of both comparators is zero. This voltage pattern is therefore characteristic of the case that no supply voltage is present at the input of the test circuit. If the supply voltage is switched off, this applies in the event that there is still enough energy in the DC link voltage of the ECG to continue to operate it. In response to determining that the supply voltage has been turned off, all important data is typically stored before the energy in the DC link also approaches zero.

In addition to 1 It should be noted that it is not necessary to provide two comparators for the evaluation circuit. It is also possible, instead of the two comparators K1 and K2, to provide a single one whose input for the reference voltage is alternately supplied via a changeover switch to a higher and a lower reference voltage V _{ref / high} or V _{ref / low} . To be able to evaluate the output voltage of the single comparator, then additionally the switching frequency of the switch must be taken into account. This case is not shown in the drawings.

The inventive circuit, which in 3 is shown, largely corresponds in structure to the circuit 1 , which is why only the parts are to be described in the following, in which it differs from the prior art.

The voltage drop across the measuring resistor R4 is evaluated by an evaluation circuit having a capacitor C2a, an AC / DC evaluation circuit, an AD converter and an analysis circuit with a logic for the supply voltage analysis. The voltage drop across the measuring resistor R4 is denoted by V _{ac / dc} . The AC / DC evaluation circuit is supplied to the drop across R4 measurement voltage. The analysis circuit is also supplied via the measuring resistor R4 dropping measurement voltage V _{ac / dc} via the AD converter. The analysis circuit outputs the result supply voltage analysis as V _mains out.

While in the prior art, the discrimination between AC and DC supply voltage is in the foreground, the present invention aims at a more specific evaluation of the supply voltage, for. B. on overvoltage (for example, by reverse polarity), amplitude, average value of the AC voltage or detection of modulated on the AC supply voltage information. The actual detection of the voltage value is the goal of the invention.

In 3 are the comparators off 1 replaced by an evaluation circuit, with which the different supply voltages can be distinguished from each other. Your build can be from the overlooking 1 described differ comparator arrangement. For example, the voltages can also be determined by using a μC or an ASIC. Ultimately, it is only important that the evaluation circuit can distinguish the different voltages V _mains and can generate corresponding output signals.

By analyzing the supply voltage through the analysis circuit, which may consist of a μC or an ASIC and receives the digital signals from the AD converter, further evaluations of the voltage V _{ac / dc} can take place. The evaluation circuit and the analysis circuit can also be realized by a μC or an ASIC.

In one aspect, the AD converter may be an adaptive AD converter for which a dynamic time window for the measurement / conversion is determined. For z. B. determines the zero crossings of the voltage, whereby the frequency of the voltage V _mains can be determined. Based on this, a time window for a signal measurement can be determined. Although the signal could also be measured in a fixed time window. However, this would make the measurement more inaccurate. The invention proposes the voltage V _mains or their frequency via the AD converter z. B. over a period of the voltage V _mains to measure. The integrated value then corresponds to the voltage value of the voltage V _mains .

To calculate the desired parameters of the voltage V _mains , different factors are to be used taking into account the different types of voltage. This is schematically in 4 shown. Clamping affects these factors. Thus, if the point of measurement of the voltage V _{ac / dc is provided} with a clamping, this makes the calculation more difficult. In 5 is exemplified for an alternating voltage (AC), as a clamping of the positive half-wave (clamping of post halfwave), the negative half-wave (clamping of neg. Halfwave) and a full-clamping (full clamping) effect. If the circuit is designed with a clamp, this must be taken into account in the calculation. The calculation can also be done with a look-up table.

In addition, the RMS value (root mean square value / RMS value) of, for example, the AC supply voltage can also be determined in order to set parameters in the operating device, for example the operation of the PFC circuit supplied by the rectified AC voltage.

In addition, it may be provided that the evaluation of the voltage V _mains takes place in such a way that signals modulated onto the mains voltage (power line, duration and / or repetition rate of a pushbutton or switch actuation) can be detected for the purpose of evaluating the information.

Yet another way to exploit this voltage path is to generate a DC supply voltage, for example, to a controller (microcontroller, ASIC, etc.) by rectifying the AC voltage provided by this path.

The capacitor C2a may also be larger in size than the capacitor C2 1 , which is used in the prior art for RF filtering of the applied signal and is dimensioned accordingly. The inventively provided capacitor C2a can thus z. B. be used to integrate the applied signal.

One way to connect the measurement or analysis of the voltage with the start is the following: The analysis can be determined whether the amplitude of the applied voltage V _{mains is} high enough to perform a start. In particular, the startup is not performed when due to the amplitude of the voltage V _{mains is} to be expected that, for example, starting the power components such as the half-bridge inverter would overstrain the applied voltage V _mains .

As a further improvement to the prior art is provided to allow a more accurate voltage detection of V _mains , if no detection of zero crossings occurs. This is in the 4 - 8th shown as an example.

The invention now provides two detection thresholds ES1, ES2 which are incorporated into the 6 - 10 are indicated by solid lines.

If an AC supply voltage V _mains with an amplitude applied to the input side, the resulting waveform of the voltage V _{ac / dc} periodically alternately z. B. the detection threshold ES1 below or exceed, which is referred to as "toggle". This is in 6 for an AC voltage of z. B. 170V shown. 7 shows the behavior at an AC voltage of 300 V. The "toggle" behavior is therefore characteristic of the AC supply voltage.

8th and 9 show a behavior for a positive rectified AC voltage V _mains . The measuring path according to the invention now yields the shown V _{ac / dc} signal which is always above the detection threshold ES2 and below the detection threshold ES1. Thus, no threshold is crossed (no "toggle"), which is indicative of rectified AC voltage. The position relative to the detection thresholds ES1, ES2 is then particularly indicative of the positively rectified AC voltage. 8th shows an exemplary behavior with a positive rectified AC voltage V _mains of 170 V, 9 in exemplary behavior with a positive rectified AC voltage V _mains of 290 V.

10 shows a behavior for a negatively rectified AC voltage V _mains . The measuring path according to the invention now yields the shown V _{ac / dc} signal always above the detection threshold ES1. Thus no threshold is crossed (no toggle). The position relative to the detection thresholds ES1, ES2 is then particularly indicative of the negatively rectified AC voltage. 10 shows an exemplary behavior with a negatively rectified AC voltage V _mains of 170 V. Higher voltages only shift the voltage V _mains further beyond the detection threshold ES1.

If, on the other hand, the signal resulting above the measuring path is constantly below the detection threshold ES2, a state "no mains" is concluded. By "no mains" is to be understood that the voltage V _{mains has} an insufficient amplitude, or in fact no voltage V _mains is present. If voltage V _mains is not present, a signal can still result in this path due to energy stored in the capacitor, which, as stated, will be significantly below the evaluation threshold.

If a rectified AC voltage is detected as an input voltage, this can be interpreted as an emergency light case and a corresponding emergency lighting can be initiated.

It is also possible by analyzing the analysis circuit to differentiate voltages of different countries and make country-specific settings. So z. B. adjust the ballast parameters / operating parameters that meet local regulations.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0939476 B1 [0003]
• DE 102007040555 A1 [0004, 0008, 0008]

Claims (10)

Operating device for lamps with: - Separate measuring circuits (M1, M2), to decompose a voltage rectified by a rectifying means (V _mains ) into a positive and a negative voltage component, the voltage (V _mains ) z. An evaluation circuit which evaluates the voltage components (V _{ac / dc} ) of the two measuring circuits (M1, M2) for identifying the type of applied voltage, and an analysis circuit, which preferably analyzes the voltage components (V _{ac / dc} ) via an AD converter and calculates further characteristics of the voltage (V _mains ), e.g. Example, an overvoltage, in particular by reverse polarity, an amplitude value, an average value of the voltage (V _mains ) and / or an information modulated on the voltage. Operating device for lighting means according to claim 1, wherein the analysis circuit determines a frequency of the voltage or a voltage value. Operating device for lamps according to claim 1 or 2, wherein the AD converter is adaptive and due to a frequency of the voltage (V _mains ) a time window for a measurement of the voltage components (V _{ac / dc} ) is predetermined. Lighting device for lamps according to one of the preceding claims, wherein the analysis _circuit measures the voltage components (V _{ac / dc} ) over a period of the voltage (V _mains ). A lighting equipment according to any one of the preceding claims, wherein the analysis circuit for the calculation uses different factors depending on the detected voltage (V _mains ). Lighting device for lamps according to one of the preceding claims, wherein the factors depend on whether a clamping is provided. Lighting device for lamps according to one of the preceding claims, wherein the analysis _circuit detects the zero crossings of the voltage (V _mains ). Operating device for lamps according to one of the preceding claims, wherein in the analysis circuit at least one threshold (ES1, ES2) is provided and the analysis circuit detects the applied voltage (V _mains ) due to their behavior with respect to the at least one threshold. Circuit for evaluating a power supply for a lamp supplied supply voltage (V _mains ), which in at least two of at least three different temporal forms such. As rectifying means for the present voltage, wherein the rectifying means are designed so that they decompose the present voltage into a positive and a negative voltage component, that each of the two voltage components a Voltage source for a separate measuring circuit (M1, M2) forms, and characterized in that - an evaluation circuit, which evaluates the currents of the two measuring circuits to identify the type of applied voltage, the circuit comprises an analysis circuit, via an AD converter the Voltage components (V _{ac / dc} ) analyzed, and other characteristics of the voltage (V _mains ) calculated, z. Example, an overvoltage, in particular by reverse polarity, an amplitude value, an average value of the voltage (V _mains ) and / or an information modulated on the voltage. A method for evaluating a power supply for a lamp supplied supply voltage (V _mains ), which at least in two of at least three different temporal forms such. B. as AC voltage, as a pulsating DC voltage or as a constant DC voltage, wherein the present voltage is rectified, such that it is decomposed into a positive and a negative voltage component, that the two voltage components as voltage sources for two measuring circuits (M1, M2) and that the currents in the two measuring circuits are evaluated to identify the type of voltage present, an analyzing _circuit analyzing the voltage components (V _{ac / dc} ) via an AD converter and calculating further characteristics of the voltage (V _mains ), z. Example, an overvoltage, in particular by reverse polarity, an amplitude value, an average value of the voltage (V _mains ) and / or an information modulated on the voltage.

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