DE102007040555A1 - Method for identifying type of voltage, particularly operating voltage supplied to operating device for emergency light, involves rectifying available voltage, such that it is divided into positive and negative voltage component - Google Patents

Abstract

The method involves rectifying an available voltage, such that the available voltage is divided into a positive and a negative voltage component. The two voltage components are applied as voltage sources for two measuring circuits (M1,M2). The current in the two measuring circuits are evaluated for identifying the type of the available voltage. The current in the measuring circuits are affected, such that the intensity of current in the two measuring circuits is different. An independent claim is included for a circuit for identifying the type of a voltage, particularly an operating voltage supplied to an operating device for an emergency light.

Description

The The invention relates to a method and a circuit for identifying the type of voltage, in particular a control gear operating voltage supplied to emergency lighting lights, that in at least two of at least three different temporal Course forms, such as. B. as AC voltage, as a pulsating DC voltage or can be present as a constant DC voltage.

After EP 0 939 476 B1 is a device for central emergency lighting known. This device includes a bridge rectifier which is turned on in a first state of emergency operation in the 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.

Of the Invention is based on the object, a method and a circuit specify the type described above, with the / the type of a present voltage, in particular the one operating device for emergency lighting supplied operating voltage is identifiable.

The Task is for the method according to the invention thereby solved the present voltage is rectified so, that they are in a positive and a negative voltage component is decomposed that the two voltage components as voltage sources be used for two measuring circuits, and that the Currents in the two measuring circuits for identification the type of voltage present are evaluated.

The solution for the circuit goes from the after EP 0 939 476 B1 known device, ie of a circuit for identifying the type of voltage, in particular the operating equipment for emergency lights supplied operating voltage in at least two of at least three different temporal forms such. B. as alternating voltage, as a pulsating DC voltage or as a constant DC voltage, with rectification means for the present voltage, and is that the rectifying means are designed so that they decompose the present voltage into a positive and a negative voltage component, that each of two voltage components forms a voltage source for a separate measuring circuit, and that an evaluation circuit is provided which evaluates the currents of the two measuring circuits to identify the type of applied voltage.

Next Building Measures are the subject of the proceedings Claims 2 and 3 and the circuit object of claims 5 to 13. Other developments of the invention are the subject of subclaims 7 to 10.

One Embodiment of the invention will be described below of the drawings.

It demonstrate:

1 a circuit diagram of the circuit for identifying the type of operating voltage supplied to an operating device for emergency lights, which may be present as AC voltage, as a pulsating DC voltage, as a constant DC voltage or as a zero voltage (no voltage);

2 to 25 Voltage curves at individual points of the circuit at the different operating voltage types.

The operating voltage to be tested 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 or as a zero voltage (no voltage). The circuit is used to identify the type of voltage. For this purpose, it must first pass through a noise filter, which consists of two symmetrical series inductors L1 and L2 and a transversely connected capacitor C1. The output of the noise filter is connected to terminals 1 and 2 the one diagonal of a bridge rectifier B, which is formed by four bridge diodes D1, D2, D3 and D4. A connection 4 the other diagonal of the bridge rectifier B is grounded M. The other terminal 3 the other bridge diagonal leads to a voltage that is further processed, whereby it is unimportant in which way the further processing takes place.

For the following description and the corresponding representations in the individual figures, the simplicity is assumed that the voltage applied to the input of the noise filter V _mains through the noise filter undergoes no change, so that the operating voltage V _mains also at 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 goes 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 goes from the terminal 2 of the bridge rectifier B and continues to flow through the separate resistor R2, the common resistor R3, the common sense resistor R4, via ground M, through the bridge diode D4 to the terminal 1 of the bridge rectifier B.

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

Current flows in the measuring circuit M1 as long as the connection 1 is positive and the connection 2 negative. Conversely, in the measuring circuit M2, current flows when the terminal 2 positive and the connection 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 suppression 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, receives the measuring voltage drop across R4 and, on the other hand, the voltage V _{ref / high} as a 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. The output voltage of the comparator K1 is denoted by _{Vout / high} , while the output voltage of the comparator K2 is denoted by _{Vout / low} .

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

In 2 a first case for the operating voltage V _{mains is} shown in which this consists of positive and negative power 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 is in 3 shown.

4 now shows the evaluation of the voltage curve according to 3 in the two comparators K1 and K2. The output voltage of the comparator K1 is in 5 and the output voltage of the comparator K2 is shown in FIG 4 shown. It can be seen 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 FIG 3 equivalent. 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 according to FIG 5 only every second half wave, and that with the higher amplitude, produces an output pulse. If the operating voltage V _{mains is} a normal mains voltage with the frequency of 50 Hz, so occur at the output of the comparator K1 pulses at the pulse repetition frequency of 50 Hz, while at the output of the comparator K2 pulses occur at the pulse repetition frequency of 100 Hz. This combination thus makes it possible to identify an ordinary mains voltage as the operating voltage.

6 now shows an operating voltage V _mains , which consists only of positive network half-waves. Such an operating voltage is generated for example by a bridge rectifier. The only positive network half-waves cause only in the measuring circuit M1 with the larger separate resistor R1, a current flows, due to both half-waves. In the measuring circuit M2, however, no current flows. The via the measuring resistor R4 decreasing measuring voltage is in 7 shown. The output voltage of the comparator K2 is in 8th and the output voltage of the comparator K1 is shown in FIG 9 shown. It can be seen that pulses with a pulse repetition frequency of 100 Hz occur at the output of both comparators K1 and K2. This voltage pattern is characteristic for the in 6 shown operating voltage V _mains . In other words, those in 6 shown operating voltage due to the in the 8th and 9 be identified pulse sequence shown.

In 10 Now the case is shown that the operating voltage V _mains consists only of negative mains half-waves. 11 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 separate resistor R2. 13 now shows that at the output of the comparator K1 with the higher threshold V _{ref / high} no voltage occurs, while according to 12 the output voltage of the comparator K2 with the lower threshold value V _{ref / low} consists of pulses with the pulse repetition frequency of 100 Hz. This voltage pattern is characteristic for the in 10 shown operating voltage V _mains .

According to 14 the operating voltage V _mains consists of a constant positive DC voltage. According to 15 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 of the in 14 shown operating voltage V _mains .

18 shows the case that the operating voltage is a negative DC constant voltage V _mains . This has according to 19 at 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 value V _{ref / high} for the comparator K 1, but higher than the lower threshold value V _{ref / low} for the comparator K 2. This has the consequence that at the output of the comparator K2 according to 20 a constant DC voltage occurs while at the output of the comparator K1 according to 21 no tension occurs. This voltage pattern is therefore characteristic of the in 18 shown operating voltage V _mains .

22 now shows the case that at the input of the test circuit is no voltage at all. V _mains is zero. This is according to 23 As a result, 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 according to the 25 and 24 Zero. This voltage pattern is therefore characteristic of the case that no operating voltage is present at the input of the test circuit. If the operating 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 operating 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 added 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.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 0939476 B1 [0002, 0005]

Claims (13)

A method of identifying the type of voltage (V _mains ) that occurs in at least two of at least three different time histories, such as. B. as alternating voltage, as a pulsating DC voltage or as a constant DC voltage, characterized in that 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. Method according to claim 1, characterized in that that the current in at least one of the measuring circuits (M1, M2) is influenced so that the currents of the currents in the two measuring circuits are different. Method according to claim 1 or 2, characterized that the two measuring circuits (M1, M2) in a common circuit section be merged to a common measurement voltage to generate, to identify the type of voltage present is evaluated. Circuit for identifying the type of voltage (V _mains ), in particular the operating voltage supplied to an operating device for emergency lights, which in at least two of at least three different time courses, such. B. as AC voltage, as a pulsating DC voltage or as a constant DC voltage, with rectification means for the present voltage, characterized in that that the rectifying means are designed so that they decompose the present voltage into a positive and a negative voltage component, that each of two voltage components forms a voltage source for a separate measuring circuit (M1, M2), and that an evaluation circuit part (C2, K1, K2) is provided, which evaluates the currents of the two measuring circuits to identify the type of applied voltage. A circuit according to claim 4, characterized in that the rectification means are constituted by a bridge rectifier (B), that the voltage whose kind is to be identified is connected to the terminals ( 1 . 2 ) is applied to one diagonal of the bridge rectifier, and that both separate measuring circuits (M1, M2) between the terminals ( 1 . 2 ) of a diagonal of the bridge rectifier. A circuit according to claim 1 or 5, characterized, that each of the two separate measuring circuits (M1, M2) has a separate one Resistor (R1, R2) contains the resistance values the two separate resistors (R1, R2) differ from each other, and that two measuring circuits (M1, M2) at least one common measuring resistor (R3). Circuit according to Claim 6, characterized in that the evaluation circuit part (C2, K1, K2) has at least one threshold value transmitter (K1, K2) which evaluates the measuring voltage (V _{ac / dc} ) across the common measuring resistor (R4) of the two measuring circuits (M1, M2). contains. Circuit according to Claim 7, characterized in that the threshold value transmitter (K1, K2) responds at a lower (V _{ref / low} ) and an upper threshold value (V _{ref / high} ). Circuit according to Claim 7 or 8, characterized in that the threshold value transmitter is formed by two comparators (K1, K2) connected in parallel, of which the one next to the measuring voltage (V _{ac / cd} ) the lower threshold value (V _{ref / low} ) and of which the other the measurement threshold (V _{ac / cd} ), the upper threshold (V _{ref / high} ) is supplied to the other. Circuit according to Claim 7 or 8, characterized in that the threshold value transmitter is formed by a comparator to which, in addition to the measuring voltage (V _{ac / dc} ), one of the two threshold values (V _{ref / high} , V _{ref / low} ) is supplied, that the two Threshold values (V _{ref / high} , V _{ref / low} ) are alternately supplied to the comparator via a changeover switch, and that the evaluation circuit evaluates the voltage occurring at the output of the comparator taking into account the switching frequency. Circuit according to one of claims 6 to 10, characterized characterized in that the common resistance (R4) of the two measuring circuits (M1, M2) bridged by a suppression capacitor (C2) is. Circuit according to one of claims 6 to 11, characterized in that between the separate resistors (R1, R2) of the two measuring circuits (M1, M2) and the common Measuring resistor (R4) Another common series resistor (R3) is switched. Circuit according to one of Claims 5 to 12, characterized in that the present voltage (V _mains ), the type of which is to be identified, is supplied to the bridge rectifier (B) via two interference suppression chokes (D1, D2) connected in series and a transverse interference suppression capacitor (C1 ) is supplied.