WO2014172729A1

WO2014172729A1 - Module having passive measurement signal feedback via charge-storage device

Info

Publication number: WO2014172729A1
Application number: PCT/AT2014/000087
Authority: WO
Inventors: Hans Auer; Thomas Dumka; Andre Mitterbacher
Original assignee: Tridonic Gmbh & Co Kg
Priority date: 2013-04-26
Filing date: 2014-04-25
Publication date: 2014-10-30
Also published as: DE102013207704A1; DE112014002160B4; AT15741U1; DE112014002160A5

Abstract

In one aspect, the invention relates to a module for operating at least one illuminant, preferably at least one LED, said module having at least one electrically insulating barrier, which separates a primary side that can be supplied, originating from a mains voltage, from a secondary side of the module, from which the at least one illuminant can preferably be supplied. A secondary-side passive circuit is provided, which is connected in a supply path to a primary-side control circuit across the barrier via at least one capacitor. The primary-side control circuit is designed to apply a test signal with predetermined temporal development to the secondary-side passive circuit and simultaneously to monitor a measurement signal generated thereby on the secondary side and fed back into the supply path.

Description

Module with passive measurement signal feedback via charge storage

The present invention relates to a module for the operation of at least one light source / a light path, preferably at least one LED.

In particular, the invention relates to an LED module or an LED converter having an electrically insulating barrier, e.g. a so-called SELV barrier (safety extra low voltage barrier), ie a safety extra-low voltage barrier, e.g. Circuit areas with

Safety extra-low voltage isolated from other circuit parts.

The invention particularly relates to a module whose output power / output current / output voltage (hereinafter only the term output voltage is used) can be set by selecting the output voltage via a select input of the module. For example, at least one selector resistor can be connected to the selector input and then the output voltage can be adjusted depending on a resistance value of the connected selector resistor.

A control circuit of the module therefore detects a measurement signal representing the resistance of the connected resistor. In the following, this concept is referred to as "Iselect." In particular, a voltage or current measuring signal with regard to the voltage / current through the light source (Iselect) can be tapped off at the selector resistor.

Furthermore, the invention relates to modules which have a temperature measuring unit (eg NTC, negative temperature coefficient resistor, PTC, positive temperature coefficient resistor, or thermistor).

The control circuit can thus alternatively or additionally detect at least one further measurement signal, which reflects a temperature determined by the temperature measurement unit. This can e.g. be a temperature coefficient, which is determined in particular by means of a variable electrical resistance whose value varies reproducibly by a change in temperature. In this case, the measuring signal then again indicates a resistance value. The measurement signals are generally voltages / currents which either represent resistance values or by means of which the resistance values can be determined.

The temperature is determined, for example, to change the output voltage of the module depending on the determined temperature, for example, to shut down the module at too high / too low temperatures. This concept is referred to below as "intelligent temperature management" (ITM).

The above-mentioned electrically insulating barrier divides the module with respect to the barrier into a primary side and into a secondary side, e.g. Also referred to as SELV page. The primary side is often supplied directly or indirectly starting from a mains supply (AC / DC voltage / current), while starting from the secondary side, the connectable light source can be supplied directly or indirectly.

The invention is aimed at modules in which the detection and evaluation of the measurement signals is performed by a primary-side control circuit. That is, on the secondary side, preferably no control circuit for detecting and evaluation is provided, in particular no IC, ASIC or microcontroller.

Even with relatively simple applications, it is often desirable here to carry information or measurement signals from the secondary side of the barrier to the primary-side control unit.

For example, it is desirable to have temperature information, e.g. read out via a secondary side

Temperature measuring resistor (NTC, PTC) to lead to the primary side. The tapping of the temperature information on the secondary side is desirable in this case, since the temperature measuring unit can be arranged so close to the light source.

Next is the connectable, for example, with the voting input of the module electoral resistance for setting the

Output voltage is a component that can be used and replaced by a human user, in particular by differently sized resistors.

In this case, the human user can come into contact with conductive parts of the module, which is why preferably the secondary side of the module with the safety extra-low voltage (low-voltage power supply, SELV or LVPS, low voltage power source) can be operated. Therefore, it is often desirable to pick up a voltage or current measurement signal with respect to the voltage / current through the lamp at the selector resistor and return it to the primary side. On the other hand, the primary-side control circuit can then be supplied with a higher voltage on the primary side. In the prior art, it is necessary to provide in a relatively complex manner, fed by a provided on the secondary low-voltage supply A / D converter, which then returns, for example by means of an optocoupler said signals to the control unit on the primary side of the electrically insulating barrier.

The invention now seeks to reduce the circuitry complexity and cost, and in particular bring the A / D converter, the optocoupler and the low-voltage supply in discontinuation.

The invention therefore provides an apparatus and a method according to the independent claims. Further developments of the invention are the subject of the dependent claims.

In a first aspect, the invention provides a module for the operation of at least one luminous means, preferably at least one LED, prepared with at least one electrically insulating barrier that separates a starting ^'suppliable from a power supply voltage primary side from a secondary side of the module, of which preferably the at least one lighting means is provided, wherein a secondary-side passive circuit is provided which is connected in a supply path across at least one capacitance across the barrier with a primary-side control circuit, and wherein the primary-side control circuit is adapted to the secondary-side passive circuit with a test signal create predetermined temporal development and at the same time to monitor a secondarily generated, returned in the supply path measurement signal. The passive secondary-side circuit may be a resistance circuit, in particular a measuring resistor network.

On the secondary side, at least one selector resistor and / or a temperature measuring resistor with the primary side

Control circuit connected.

The at least one capacitor may be a Y capacitor.

The supply path may include a path for returning the measurement signal.

The test signal may be a current or voltage jump.

The feedback measurement signal can only depend on resistors connected in the passive circuit.

The control circuit may determine from the feedback signal the value of at least one secondary resistance.

The returned signal can be detected at least two times and the resistance value can be determined by extrapolation.

The module can be an LED module.

In another aspect, the invention provides a ballast with a module as described above.

In a further aspect, the invention provides a luminaire with a ballast as described above. In yet another aspect, the invention provides a method for the passive feedback of a measurement signal from the Secondary side of an electrically insulating barrier to a control circuit arranged on the primary side, which is connected in a supply path with a secondary-side passive circuit via at least one capacitance across the barrier, the primary-side control circuit to the secondary-side passive circuit applying a test signal with a predetermined time evolution and At the same time, a measurement signal generated thereby on the secondary side and fed back via the supply path is monitored.

The invention will now be described with reference to the figures. Showing:

Fig. 1 exemplifies an inventive

Circuit arrangement.

2 shows by way of example a further invention

Circuit arrangement.

3 shows an example voltage curve of a

Simulation circuit.

The invention provides the transmission from the primary side to the secondary side by means of SELV-approved capacitors, so-called Y capacitors.

Y capacitors are hereby electrical capacitors which are connected between phase, respectively neutral conductor, and touchable circuit parts, e.g. a protective earthed housing, be connected and thus bridge the electrically insulating barrier.

For Y capacitors such capacitors are permissible, which with limited capacity a verifiable increased electrical and mechanical safety, as in the event of failure it may endanger the user.

As shown in Fig. 1, a current path is formed from a control circuit S on the primary side, the two poles of a secondary-side passive circuit, a resistor circuit with at least one of said resistors (R _Iselect or a temperature _{measuring resistor RITM)} , via a respective the said specified capacitances or Y capacitors C1, C2 connects across the barrier. In Fig. 1, the passive circuit is shown schematically by the resistor R _PS .

If now executes the control circuit S on the primary side of a predetermined test signal, ie a signal with a predetermined time evolution of the current or voltage curve (for example, a jump) in the power / voltage supply of the secondary-side passive circuit, by measuring the time course of a primary side detected measuring signal to a current state of the passive circuit or the resistance R _PS are closed by secondary side resistors. For this purpose, a primary-side measuring resistor (shunt) can be provided.

It is essential that in the module, a measurement information and no energy is transmitted from the secondary side of the electrically insulating barrier to the primary side quite generally. The transmission takes place in that the passive circuit R _PS on the secondary side (in the simplest case, ohmic resistors or a PTC / NTC) is in turn connected to the primary-side control circuit S via at least one capacitance, a Y capacitor C1, C2 across the barrier , The secondary-side passive circuit can also be quite more complex than just one resistor, but preferably has no voltage supply on the secondary side, but is supplied only on the basis of the primary-side control circuit.

2 shows a circuit _alternative in which a first resistor R _Iselect on the secondary _side , in particular a selector resistor, and a second resistor R _ITM , in particular a temperature measuring resistor, are connected to the primary side

Control circuit S via a first capacitor C1 'and a second capacitor C2' are connected. Here, the feedback of the signals to the control circuit S on the primary side via a common capacitance C3 '. The capacitances are here likewise preferably designed as Y capacitors.

By applying a first test signal to a first path via the first capacitance Cl 'and the first resistor R _{Iselect, the control circuit} S can now _detect a signal on the third capacitance C3' that reproduces the resistance value of the first resistor R _Iselect .

Similarly, by applying a second test signal to a second one of the first capacitance C2 'and the second resistance R _ITM , the _{control circuit S can} detect a signal at the third capacitance C3' representing the resistance of the first resistance _Rselect .

Preferably, the control circuit S, the first and the second test signal at a time interval from each other so as to temporally separate measuring signals at the third capacitance C3 'can be tapped, the respective resistance values play. The measuring signals are current / voltage signals.

If, however, one of the paths is returned to the control circuit S via a further capacitance (not shown) so that there is no common feedback via the capacitance C3 ', then the test signals can also be applied simultaneously.

It is clear that additional measuring signals can be fed back from the secondary side by means of additional capacitances.

After applying the test signal to one of the paths

received measurement signal, in particular the / the received voltage / current, from the ^' secondary side resistance. This is shown in FIG. 3 for a simulation circuit which corresponds in its construction to the circuit arrangement from FIG. 1. The quantity Il-neg / mv plotted in the diagram from FIG. 3 results from a constant current which is applied to the capacitor C1 on the primary side.

Because of a dripped oscillation caused by parasitic capacitances, it may be necessary to carry out the detection of the measuring signals, in particular of the voltage, at different / specific points in time, or to repeat them. However, since the capacities or their dimensions are known, the resistance values can always be determined.

The capacities used preferably have large tolerances. Therefore, a two-point measurement can be performed and the value of a resistance can be extrapolated from the measurement by the control circuit S.

Claims

claims

1st module for the operation of at least one

Illuminant, preferably at least one LED, with

at least one electrically insulating barrier, which separates a primary side, which can be supplied from a mains voltage, from a secondary side of the module, from which the at least one lighting device can preferably be supplied, wherein

a secondary-side passive circuit is provided which is connected in a supply path across at least one capacitance across the barrier with a primary-side control circuit, and wherein the primary-side control circuit is adapted to the secondary-side passive circuit to apply a test signal with a predetermined time evolution and simultaneously thereby monitored secondary side generated, fed back in the supply path measurement signal.

2. Module according to claim 1, wherein the passive

secondary-side circuit a resistance circuit,

in particular, a measuring resistor network.

3. Module according to claim 1 or 2, wherein the secondary side at least one selector resistor and / or a

Temperature measuring resistor connected to the primary-side control circuit.

4. Module according to one of the preceding claims, wherein the at least one capacitor is a Y-capacitor.

5. Module according to one of the preceding claims, wherein the supply path comprises a path for returning the measurement signal.

6. Module according to one of the preceding claims, wherein the test signal is a current or voltage jump.

7. Module according to one of the preceding claims, wherein the returned measurement signal only depends on connected in the passive circuit resistors.

8. Module according to one of the preceding claims, wherein the control circuit is adapted to, from the

returned signal the value of at least one

Secondary resistance to determine.

9. Module according to one of the preceding claims, wherein the control circuit is adapted to the

To detect feedback signal at least two times and to determine the resistance value by extrapolation.

10. Module according to one of the preceding claims, wherein the module is an LED module.

11. ballast with a converter according to one of the preceding claims.

12. Lamp with a ballast according to claim 12.

13. A method for the passive feedback of a measurement signal from the secondary side of an electrically insulating barrier to a control circuit arranged on the primary side, which is connected in a supply path with a secondary-side passive circuit via at least one capacitance across the barrier, wherein the primary-side control circuit to the secondary side passive Circuit applies a test signal with a predetermined time evolution and at the same time monitors a secondary signal generated via the supply path feedback measurement signal.