DE102015217835A1 - Supply unit for a bus - Google Patents

Abstract

The invention relates to a method for operating a power supply system, preferably in a lighting system (A), a power supply system (C) for a bus at rest voltage leading bus with at least two parallel supply units (1) and a supply unit (1) for a voltage at rest leading bus (3), wherein the supply unit (1) is adapted to bus subscribers (8, 8 ', 8' ', 8' '') to supply by means of the bus (3) with a DC voltage, wherein a maximum current drain (Ix) from the bus (3) is limited by bus subscribers (8, 8 ', 8' ', 8' '') to a predetermined value, comprising a circuit which is set up, the current current consumption from the bus (3) to detect by shorting the bus (3).

Description

The invention relates to a method for operating a power supply system, preferably in a lighting system, a power supply system for a bus at rest voltage leading bus with at least two parallel supply units and a supply unit for a voltage at rest bus leading, wherein the supply unit is designed to bus subscribers to supply the bus with a DC voltage.

In this case, the illumination system preferably has the bus, which is designed to carry voltage in the idle state and therefore to serve as a voltage supply for actuators and sensors in the illumination system. An example of such a bus is the Digital Addressable Lighting Interface, in short: DALI, used in the IEC 62386 normalized.

In building automation, DALI is a protocol for the control of lighting equipment, such as switching power supplies, electronic ballasts or electric power dimmers to control bulbs, to monitor their operating status and / or power.

Each operating device, which has a DALI interface, can be controlled individually via corresponding DALI addresses and can change the intensity of a light source or a sensor in the lighting system. Moreover, actuators are provided. A bidirectional data exchange between a DALI control unit and a DALI device determines, for example, the status of a single light source or a group of light bulbs or the operating unit itself and can also control this. DALI uses a serial asynchronous data protocol with a transfer rate of 1200 bps at a voltage level of 16 V using two-wire communication.

The power supply of the lighting system via a separate bus. Two communication lines DA + and DA- are preferably galvanically isolated from this mains supply and polarity-free. These two communication lines DA + and DA- serve simultaneously as power supply lines. These cables can be laid in any topology, ie star, line or tree structure. Terminators at the end of the power supply lines are not necessary. The two communication lines, which also serve as supply lines, are referred to below as the voltage-carrying bus.

From the DALI standard IEC 62386 It can be deduced that a maximum of 64 actuators per bus can be controlled. The maximum current drain of the bus is limited to a predetermined value and is preferably 250 milliamps, which is hereinafter referred to as the maximum current drain.

To ensure that the maximum current drain of 250 milliamperes is not exceeded from the bus, a special DALI supply unit is provided. This DALI supply unit produces a constant output current of nominally 200 milliamps to 250 milliamps with a 16 volt power supply in the sleep mode of the lighting system.

For a current current consumption above the specified value for a maximum current consumption, the bus users connected to the bus are not designed so that the bus participants are to be protected against a current drain above the maximum current drain. In particular, a parallel connection of several DALI supply units is therefore not possible, since with parallel connection an output current would be generated on the bus, which is above the maximum current drain.

In addition, according to DALI standard IEC 62389 provided that a communication between individual elements of the lighting system, hereinafter also referred to as a bus subscriber, is impossible over the bus until a start-up latency has expired. The DALI bus is considered stable only after the end of this start procedure waiting time and allows communication between the bus users. The startup procedure wait time is preferably 600 milliseconds.

Thus, if several DALI supply units are operated in parallel, a current flowing through the bus could exceed the maximum current drain within this start procedure waiting time, whereby the bus users would possibly be overloaded and thus would be damaged or destroyed.

Moreover, in the DALI lighting system bus, it is not possible to operate a DALI lighting element, such as a light bulb or power dimmer or electronic ballast, independently of a DALI power supply.

Sometimes when planning lighting systems in buildings or parts of buildings, there is a desire to provide the most flexible lighting system possible. Thus, it is desirable to have a variety of smaller lighting systems install, for example, with a small number of bulbs, actuators and sensors. With such a small number of elements, the maximum current drain of 250 milliamps is never reached.

Alternatively or additionally, it is desirable to cluster the bus flexibly, that is to connect the bus users in the bus as flexibly as possible to a first or a second lighting subsystem or to flexibly expand an existing lighting system. Since a parallel connection of several DALI supply units according to the DALI standard is not provided, a separate DALI supply unit must be provided for each conceivable cluster.

In all of these design variants, the comparatively cost-intensive DALI supply units are to be used. When using such DALI supply units, the supply of the bus of the lighting system would disadvantageously be on the one hand oversized and on the other hand only expensive to produce.

It is therefore an object of the present invention to provide a power supply system and a supply unit, which is especially for smaller lighting applications, for example, for operating a single-digit number of actuators and sensors, used and eliminates the above-mentioned disadvantages. In particular, a lighting system is to be supplied highly flexible with energy, the supply unit used for this purpose should not be oversized and still comply with the DALI standard.

The object is achieved with the measures described in the independent claims. Advantageous embodiments are described in the respective dependent claims.

In a first aspect of the invention, a supply unit for a bus at rest voltage is proposed. The bus subscribers are supplied by the bus with a DC voltage, wherein a maximum current drain from the bus is limited by bus subscribers to a predetermined value. The supply unit has for this purpose a circuit which is set up to detect the current current drain from the bus by short-circuiting the bus.

By this circuit thus the current detected current consumption of the bus is detected, so that exceeding the predetermined value for the maximum current drain is detected. Thus, measures can be taken to limit the current drain or to determine if the supply unit can supply additional power to the bus without exceeding the value.

By idle state is meant a bus state by passing only a voltage or a current on the bus and in particular no data communication.

A predefined value is, for example, the maximum permissible current according to the DALI standard. This value is stored, for example, in a storage unit of the supply unit and can also be adapted for a respective changed lighting system.

Preferably, the circuit of the supply unit to a short-circuit switch, which is suitable for shorting the bus. Moreover, a control unit is provided in the circuit of the supply unit, wherein the control unit is adapted to switch the short-circuit switch in a first switching state in which the bus is short-circuited and to switch the short-circuit switch in a second switching state in which the short circuit of the bus is canceled , The control unit is further configured to record the current draw from the bus in the first switching state of the short-circuit switch.

Preferably, the bus is a DALI-standardized bus of a lighting system. At least one bus participant is an element in the lighting system. The illumination system is preferred according to the DALI standard IEC 62389 to operate.

As an element in the lighting system, for example, a light source, an operating device for a light source, a power dimmer, an actuator and / or a sensor for a lighting system to understand.

The bus thus comprises two supply lines DA + and DA-, which connects all connected bus subscribers in parallel with the supply unit. These supply lines are connected in parallel with each element of the lighting system in different topology.

According to the invention, it is now provided that a short circuit switch is provided in the circuit of the supply unit in order to connect the supply lines of the bus or to open an existing connection. In the connection between the supply lines there is for example a measuring element, preferably a current measuring resistor. The control unit of the circuit is adapted to detect a current by means of the measuring element, for example by detecting a voltage drop across the current Measuring resistor, which is converted in the control unit to a recorded current current consumption.

Thus, the supply unit of the bus can detect whether a current drain from the bus corresponds to a maximum current consumption or even exceeds it. The supply unit will not provide additional power to the bus when the maximum current drain is reached or has already been exceeded.

In this way, a modular supply system for the bus is obtained. The supply unit preferably has a maximum output current which corresponds to a fraction of the maximum current consumption of the bus. For example, the output current of the supply unit is one tenth or one fifteenth of the maximum current drain. In this way, less expensive supply units can be used.

Thus, several supply units can be connected in parallel in a power supply system and it is always ensured that the maximum current drain is not exceeded. A parallel connection thus offers the possibility that an energy supply of the bus can be arbitrarily extended / increased and further elements in the lighting system can be supplied by adding additional supply units in the power supply system. A flexible clustering of the lighting system in a building or a part of the building is thus achieved.

In a preferred embodiment, the supply unit is operable in a master mode, in which the supply unit is the main supply of the bus. In addition, the supply unit is operable in a slave mode, in which the supply unit is an auxiliary supply of the bus when needed, wherein the supply unit in the master mode or in slave mode can be operated depending on the detected current current consumption from the bus.

If there are several supply units in a power supply system, so that a main supply can be ensured by a first supply unit, wherein if necessary, at least one further supply unit can be added, as long as the maximum current drain from the bus is not exceeded. The main supply is provided by the supply unit in master mode. For each lighting system, only one supply unit is to be operated in master mode.

In a preferred embodiment, the DC voltage or the output current is provided to the bus when the short-circuit switch is switched to the second switching state. It is thus ensured that initially the supply unit does not supply the bus as long as the current current drain from the bus has not been detected. Only when it is ensured that the supply does not exceed a maximum current drain, the supply unit will provide an additional output current to the bus. Thus, the switching of the short-circuit switch is independent of providing the power supply.

In a preferred embodiment, the supply unit can be operated with a supply alternating voltage. Thus, the supply unit comprises a voltage reduction and possibly a rectification. As an AC supply voltage, for example, a mains voltage in the amount of 230 volts at 50 hertz to understand. Other nominal network supply values are not excluded from the spirit of the invention.

In a preferred embodiment, the control unit is set up, after detecting the current current consumption, to detect a current voltage value on the bus. By means of the voltage value detection it is determined whether further supply units are connected to the bus.

In a preferred embodiment, the control unit is adapted to compare the current current consumption with the predetermined value for a maximum current drain, wherein when the predetermined value is exceeded, the supply unit is operated in the master mode.

The control unit is preferably set up to detect the current current drain only after expiration of an individual random wait time. This results in the detection taking place at different times on the bus.

In a further aspect of the invention, a power supply system, preferably for a lighting system, is provided for a bus carrying a voltage at rest. A maximum current drain from the bus by bus subscribers is limited to a predetermined value. The power supply system comprises at least two supply units connected in parallel to the bus according to the previously described kind, each of the supply units being adapted to supply bus subscribers with a DC voltage by means of the bus, each of the supply units having a circuit which is set up current current drain from the bus by shorting the bus to capture. The supply units close the Bus selectively short to capture the current current drain.

Due to the selective short-circuiting, each power supply unit in the power supply system autonomously detects the current current drain from the bus and autonomously decides whether another power supply is permitted on the bus or not.

Preferably, each of the supply units waits for an individual random wait time in an initialization phase before the circuit detects the current draw of the bus.

It is preferably decided on the basis of a comparison between the currently detected current consumption and the predetermined value of the maximum current drain from the bus by bus subscribers in each supply unit, which of the supply units is operated as the main supply or auxiliary supply in the power supply system.

According to the invention, the supply units are operated as a main supply unit or auxiliary supply unit only after a preset start delay time has elapsed in the initialization phase. In this way, it is ensured that a current consumption detection is not carried out simultaneously by two supply units in the same lighting system. A falsification of measurement results is thus prevented.

In a further aspect of the invention, a method of operating a power supply system according to the previously described manner is described. The method comprises the method steps: initializing the power supply system, wherein an individual random waiting time is awaited in each power supply unit of the power supply system; Detecting a current current drain from the bus by bus subscribers by selectively shorting the bus of each supply unit; Operating the respective supply unit either in a master mode or in a slave mode, wherein the mode is selected in dependence on the currently detected current consumption from the bus; and checking a time duration in which the bus is short-circuited, restarting the process if a maximum short-circuit period is exceeded. The invention thus relates to an intelligent starting method for supplying power to a bus, preferably in a lighting system. In particular, the method expires before the start delay that is required to stabilize the bus for data communication. A parallel connection of a plurality of supply units is ensured without an actual communication between the DALI components takes place after a start time of 600 milliseconds.

The supply units are designed as minimum supply units, so that their constant output current corresponds to a value of one-tenth, for example, 20 milliamps, the maximum current consumption from the bus. In this way, many supply units can be connected in parallel without exceeding the maximum current drain in the DALI lighting system. In this way, all elements in the lighting system are also protected during the startup procedure against overloading.

In the method, a random wait time ensures that one of the supply units of the bus qualifies as a master supply unit. All remaining supply units are set up after expiry of the random waiting period to detect the current drain from the bus, for which purpose a short-circuit switch is made possible by a control unit of the supply unit.

Detecting is preferably carried out after the supply unit detecting the current consumption provides a DC voltage for the bus, wherein when the predetermined value of the maximum current consumption is exceeded, the detecting supply unit deactivates its DC voltage supply for the bus. This deactivation serves to protect the bus users connected to the bus.

The detection preferably takes place again after the supply unit detecting the current consumption has deactivated a DC voltage for the bus. If, following the re-detection, the current drain is still above the maximum current drain, the supply unit is switched in master mode operation. In this case, a master mode waiting time is waited for and a current consumption detection as long performed until the currently detected current drain is below the maximum current drain.

The method for operating a supply unit in the slave mode preferably comprises the following further method steps: detecting a voltage value on the bus by the supply unit; Re-detecting the current current drain from the bus only in the event that the sensed voltage value is above a reference voltage value; and operating the supply unit in the master mode in the event that the re-detection shows that the currently detected current consumption is above a predetermined value of a maximum current consumption from the bus by bus subscribers. In the master mode operation, current consumption detection is carried out until the currently detected current consumption is below the maximum current consumption.

In this way, it is determined in the slave mode of the supply unit, if other supply units are connected to the bus.

In a preferred embodiment, the slave mode comprises the further method steps: Waiting for a master mode waiting time in the event that the re-detection shows that the current detected current consumption is below a predetermined value of maximum current drain from the bus by bus subscribers; and recapturing the voltage value on the bus, turning off that supply unit when the recapture of the voltage value indicates that the recaptured voltage value is below the reference voltage value. In this way, it is detected that a master supply unit is already connected to the bus.

In a preferred embodiment, the power supply unit is operated in a master mode by means of the following method steps: waiting for a master mode waiting time; Recapturing the current current drain from the bus; and canceling the short circuit of the bus in the event that the re-detection indicates that the detected current draw is below a predetermined value of maximum current drain from the bus by bus subscribers.

In this way, it is achieved that first a master mode waiting time is waited in order not to compete with an already in master mode supply unit of the power supply system. In this waiting period, each individual supply unit is deactivated in slave mode, if the detected current consumption from the bus is above a maximum current consumption, for example 250 mA. In this way, a current overload is excluded.

Preferably, the master mode operation comprises the further method steps: detecting a voltage value on the bus; Waiting for a random wait time in the case where the detection indicates that the detected voltage value is above a reference voltage value; Shorting the bus; and re-capture the current current drain from the bus.

The method enables quasi-communication between parallel-connected supply units in a power supply system without actually waiting for a start-up procedure time until a stable data bus is obtained.

The invention or further embodiments and advantages of the invention will be explained in more detail with reference to figures, the figures only describe embodiments of the invention. Identical components in the figures are given the same reference numerals. The figures are not to be regarded as true to scale, it can be exaggerated in size or exaggerated simplified individual elements of the figures.

Show it:

1 a supply unit according to the prior art.

2 an embodiment of a supply unit according to the invention.

3 an embodiment of a lighting system with a power supply system according to the invention.

4 an exemplary flowchart of a method according to the invention for operating a power supply system.

5 an exemplary flowchart of an initialization phase of the inventive method according to 4 ,

6 an exemplary flowchart of a first current consumption-capture phase of the inventive method according to 4 ,

7 an exemplary flowchart of a slave mode operation of the method according to the invention 4 ,

8th an exemplary flowchart of a master mode operation of the inventive method according to 4 ,

In 1 is a supply unit 1 represented according to the prior art. The supply unit 1 includes input terminals 2 represented as power line L and the neutral line N. According to the invention, the use of a supply unit is not excluded 1 , which additionally has a protective conductor PE. The supply unit 1 also has a DALI interface, here as a bus 3 is shown with the lines DA + and DA-. Such DALI supply units serve to supply a bus 3 with a DC voltage to which DALI operating devices, electronic ballasts or power dimmers, actuators or sensors are connected as bus subscribers. The supply unit according to 1 is set up, the bus 3 with a current of 240 milliamps to supply. The supply unit is the only supply in a lighting system according to the state of the art. In doing so, a mains supply voltage of 220 volts to 240 volts is applied to the input terminals 2 created. The mains supply voltage typically has a mains frequency of 50 hertz or 60 hertz. The supply unit is therefore designed to deliver a power of 5 watts. The output voltage is 16 volts at +/- 5% tolerance. The DALI signal is not a SELV.

In particular, with such a DALI supply unit, the DALI standard IEC 62386 respected.

A disadvantage of the existing DALI system is that no parallel connection of such DALI supply units 1 is possible because the output current is allowed a maximum current drain of 250 milliamps from the bus 3 do not exceed. A communication between the individual DALI supply units is not possible, in particular, until the construction of a stabilized DALI data communication bus, so that even later regulation of the DALI supply unit would not prevent the elements located in the lighting system A from being operated with an excessively high current which would mean their damage or even destruction.

The DALI supply unit 1 according to the prior art is oversized for a variety of applications in lighting technology. A more cost-effective modular and flexible bus supply 3 for a minimalistic lighting system is therefore desirable.

According to the invention, therefore, an alternative approach to the supply of a bus 3 proposed with a DC voltage. This is a quasi-communication between parallel supply units 1 be enabled. The DALI-standardized maximum current drain of a maximum of 240 mA is not exceeded even with the supply units proposed according to the invention. An individual adaptation to existing DALI lighting systems is thus possible, with individual clustering of the lighting systems now being made possible.

In 2 is a supply unit according to the invention 1 shown. In addition to the in 1 illustrated connections 2 . 3 is according to the invention in the supply unit 1 a control unit 4 intended. The control unit 4 is designed, for example, as a microcontroller, as an ASIC as FPGA or CPLD. The control unit 4 is by bus 3 connected. In the supply unit 1 is also a short-circuit switch 5 intended. The short-circuit switch 5 is provided to the bus 3 short-circuit. For this purpose, the short-circuit switch 5 a first switching state I, to connect the line DA + and DA- together. In a second switching state II lifts the short-circuit switch 5 a connection between the power supply lines DA + and DA-. Changing the switching state of the short-circuit switch 5 is through the control unit 4 causes. This is a switching signal through the control unit 4 generated. By means of the short-circuit switch 5 can now take a current drain from the bus 3 , which flows through the supply lines DA +, DA-, are detected. For this purpose is a measuring element 6 provided in the connection between the supply lines DA +, DA-. The control unit 4 is intended to provide a voltage drop across, for example, a measuring element designed as a current measuring resistor 6 at short circuit of the short-circuit switch 5 capture. Alternatively, by means of the measuring element 6 a galvanic coupling, for example by means of coupled coils, or alternatively by means of an optocoupler. The detected current drain from the bus 3 is in the control unit 4 evaluated. Depending on the magnitude of the current value and compared to a predetermined value I _x for a maximum current drain, for example 240 mA according to the DALI standard IEC 62389 , then the provision of a power supply on the bus 3 through the supply unit 3 and opening the switch 5 or not providing the power supply and opening the switch 5 ,

According to the invention is in the supply unit 1 a memory element 7 intended. In this memory element 7 For example, DALI addresses, DALI lighting groups, DALI lighting scenarios and / or dimming values are stored which are provided for a specific setting of the lighting system A. When changing an operating device 8th in the lighting system A can now by means of the memory 7 the setting of the lighting system A are secured. All relevant data of the elements connected to the lighting systems A. 8th can thus be in memory 7 be stored. Thus, this data is used in memory 7 as backup data in the event that a control gear in lighting system A is to be replaced.

In this way, basic functionalities such as firmware settings or regulations in memory 7 be filed. If an operating device is replaced, this data is removed from the memory 7 are loaded and ready for use in the lighting system without any time-consuming initialization or installation. Additional features like dimming, group lighting and emergency lighting scenarios can also be stored in memory 7 be included.

In 3 an inventive illumination system A is shown. The lighting system A comprises a power supply system C consisting of a first supply unit 1 and a second supply unit 1' , as in the example 2 are shown. The bus 3 serves the elements 8th . 8th' . 8th' and 8th''' with a DC voltage from the supply units 1 . 1' to supply. The Elements 8th . 8th' . 8th' and 8th''' are, for example, control gear for lamps or power dimmers or electronic ballasts or sensor elements or control gear for actuators in the lighting system A. The lighting system A according to 3 is DALI standardized. The lighting system A is a comparatively small lighting system A, since only four elements are to be operated. These four lighting elements 8th . 8th' . 8th' and 8th''' can now be interconnected differently, as operated in different clusters. For example, a cluster B could consist of the two elements 8th and 8th' be formed. Such a small cluster B can by means of one of the two supply units 1 . 1' operate. Another cluster B 'may consist of the elements 8th'' and 8th''' be formed and can also by already one of the supply units 1 or 1' be powered. For example, a third cluster B "may also be formed in which all four lighting elements 8th . 8th' . 8th' and 8th''' operate simultaneously in the lighting system A. In such a cluster B "are at least two supply units 1 . 1' provided to generate the required power.

The clustering is done, for example, during installation or planning of the lighting system A. In order not to have to commit at such an early stage, can now by means of parallel switchable supply units 1 . 1' a flexible, modular and changeable structure can be obtained.

The number of supply units 1 , the elements 8th and cluster B is merely exemplary and not limited to this number.

To be able to operate this lighting system A according to the DALI standard, it must be ensured that at no time does the current current drain above a predetermined value I _x for a maximum current drain increase but all elements 8th be sufficiently supplied with energy. In addition, ensure that the supply is available within the waiting period of 600 milliseconds. This is made possible by a method for operating the power supply system C, as shown by way of example in FIGS 4 to 8th is shown.

In the 4 an embodiment of a method flow diagram for a method according to the invention for operating a power supply system C is described. The power supply system C is, for example, as in FIG 3 constructed and includes at least two supply units 1 . 1' ,

In step S1, an initialization phase of the method according to the invention is initiated. The initialization phase is in the 5 explained in more detail. In this phase S1, in particular, it is prevented that two supply units 1 . 1' at the same time the short-circuit switch 5 in the first switching state I switch.

Following the initialization phase, a first current consumption acquisition phase S2 takes place. This current consumption detection phase S2 is in the 6 explained in more detail.

The result of the current consumption acquisition phase S2 is a comparison result, to what extent a currently detected current consumption from the bus 3 is greater than a predetermined value I _X a maximum current drain, for example, the maximum allowable current of 240 milliamps when operating a lighting system A according to the DALI standard. If the current drain is greater than the predetermined value I _X in the lighting system (yes case), the master mode operation S4 is initiated. In the no case, the slave mode operation S3 is initiated for the respective supply unit 1 , Subsequent to the slave mode operation S3 or the master mode operation S4, a duration check S5 will be performed in which it is checked whether the short-circuit switch 5 one of the supply units 1 . 1' is switched over a maximum allowable time T _x in the switching state I. If so, the procedure is restarted. If this is not the case then the operation is maintained as it is set.

The method according to 4 is preferably completed before the lapse of a start-up latency of 600 milliseconds. Thus, before the end of stabilization of the DALI bus 3 already a quasi-communication between the supply units 1 generated and a stable operation of the lighting system 1 guaranteed.

In 5 is the initialization S1 of the inventive method according to 4 shown in more detail. For this purpose, the power supply system A is first turned on in step S11. Then, in step S12, the switching of the short-circuit switch 5 in the first switching state I. In this way, the bus supply line DA + is connected to the bus supply line DA-. Subsequently, a switch- _on waiting time T _{switch-on is} awaited in step S13. This is necessary to the supply unit 1 a stable operation to properly capture the current Current drain by the control unit 4 to ensure. In the following step S14 the supply unit learns 1 a random wait T _coincidence to wait. This random wait time T _random is individual for each supply unit in the power supply system C, so that a simultaneous current consumption detection by different supply units 1 is prevented. In this way, the detection of one by another supply unit 1 prevents falsified current drain.

In 6 is a first current consumption detecting phase S2 according to 4 shown. For this purpose, in step S21 a current current drain from the bus 3 detected. The short-circuit switch 5 is still closed, see initialization phase S1. The control unit 4 detects the current current drain through the measuring element 6 , In the following step S22, a comparison is made between the current current drain with a predetermined value I _{X of} the maximum current drain by the control unit 4 , If the currently detected current drain I is less than or equal to the predetermined value I _X , the first current drainage detection phase S2 is ended.

If the currently detected current drain I is greater than the predetermined value I _X , then in step S23 the supply unit 1 disabled. This is followed by another detection of the current drain from the bus 3 in step S24. Subsequently, again, a comparison S25, which corresponds to the comparison S22. If the currently detected current drain I is less than or equal to the predetermined value I _X , then the supply unit 1 operated in the slave mode operation S3 and the detection phase S2 is completed. If the currently detected current drain I is greater than the predetermined value I _X , the first current drain detection phase S2 is ended, the supply unit 1 is however operated in master mode S4.

In 7 is the slave mode operation S3 according to 4 described in more detail. In the slave mode operation S3 is switched, if in step S25 or in step S22, the detected current drain is less than the predetermined value I _X. Then, in step S31, the short-circuit switch 5 opened by switching to switching state II. Thus, the DA + line is the bus 3 from the DA line of the bus 3 separated. Then, the detection of a voltage value U of the bus takes place 3 in step S32. If a comparison S33 shows that the voltage is lower than a reference voltage value U _x , for example 9 V, it is assumed that there is no further supply unit 1 is present in the power supply system C. If the comparison _reveals that the voltage is greater than, for example, 9 V, then again a random time T is _randomly awaited in step S34. Then the short-circuit switch 5 switched back to the closed state I, see step S35. It is again the current current drain from the bus 3 detected in step S36 and S37. Here, the currently detected current drain is again compared with the value I _X , which is changed when exceeding the value I _x in the master mode according to S4.

If the current current drain is less than the value I _X , it is assumed that there is no further supply unit 1 in the power supply system C is active and the short-circuit switch 5 can be brought back to the state II according to S38. After waiting for a master mode waiting time T _master in step S39, the supply unit becomes 1 turned off, see step S40. The slave mode S3 is then ended.

In 8th is now the master mode operation S4 according to the 4 shown in more detail. First, a master mode waiting time T _Master is awaited in step S41. Subsequently, in steps S42 and S43, detection of the current current consumption takes place again. In this way, it is detected whether the current current drain is below the value I _X. Incidentally, every supply unit shuts off in this phase 1 of the slave mode operation S3, since a current current consumption was detected above the value I _X and thus the current current consumption from the bus 3 is to be reduced.

As soon as the current current drain is below the value I _X , the short-circuit switch is switched 5 in the open state I in step S44. Now, similar to the steps S33 and S32, the detection of the voltage on the bus 3 according to steps S45 and S46. If the voltage is greater than a reference voltage value U _x , it is assumed that only one master supply unit 1 is present in the lighting system A and this takes over the main supply. If it is determined in step S46 that the voltage is lower than the reference voltage value U _x , then there are further supply units 1 . 1' in master mode in the lighting system 1 available. Then, a random _{waiting time} T _is waited for by _chance (S47) and the short-circuit _switch 8th switched back to the switching state I according to step S48. Again, current drain detection is performed in step S49. If the current current drain is greater than the value I _x , the master mode is again run in accordance with step S 4.

By in the 4 to 8th described procedures is ensured that the maximum current drain is never above a value I _x and the lighting system A can be adapted to its corresponding clustering B, B ', B''.

All shown, illustrated or claimed features can be combined with each other.

LIST OF REFERENCE NUMBERS

1

 Power supply unit

2

 input port

3

 Power lines

4

 control unit

5

 Short-circuit switch

6

 Current sense resistor

7

 storage area

8th

 Element in the lighting system

S1

initialization

S2

First current draw-capture phase

S3

Slave mode operation

S4

Master mode operation

S5

Connection time-Verifiable step

S11-S14

 initialization

S21-S25

Current drain-detecting steps

S31-S40

Slave-mode steps

S41-S49

Master mode steps

A

 lighting system

B, B ', B' '

 Lighting subsystem, clusters

C

 Power supply system

I

 First switching state

II

Second switching state

I _x

Current reference value

U _x

Voltage reference value

T _coincidence

 Random waiting time

T _master

 Master mode wait time

T _{switch on}

Start delay time

T _x

Connection period

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 non-patent literature

• IEC 62386 [0002]
• IEC 62386 [0006]
• IEC 62389 [0009]
• IEC 62389 [0022]
• IEC 62386 [0064]
• IEC 62389 [0068]

Claims (20)

Supply unit ( 1 ) for a bus at rest ( 3 ), wherein the supply unit ( 1 ) is designed to allow bus subscribers ( 8th . 8th' . 8th'' . 8th''' ) by means of the bus ( 3 ) with a DC voltage, wherein a maximum current drain (I _x ) from the bus ( 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ) is limited to a predetermined value, comprising a circuit which is set up, the current current consumption from the bus ( 3 ) by shorting the bus ( 3 ) capture. Supply unit ( 1 ) according to claim 1, wherein the circuit comprises: - a short circuit switch ( 5 ) for shorting the bus ( 3 ); and a control unit ( 4 ), the control unit ( 4 ): - the short-circuit switch ( 5 ) in a first switching state (I), in which the bus ( 3 ) is short-circuited; and - the short circuit switch ( 5 ) in a second switching state (II), in which the short circuit of the bus ( 3 ) will be annulled; - wherein the control unit ( 4 ) is further set, in the first switching state (I) of the short-circuit switch ( 5 ) the current current consumption from the bus ( 3 ) capture. Supply unit ( 1 ) according to one of claims 1 or 2, wherein the bus is a DALI-standardized bus of a lighting system (A) and wherein at least one bus subscriber ( 8th . 8th' . 8th'' . 8th''' ) is an element in the lighting system (A). Supply unit ( 1 ) according to one of the preceding claims, wherein the supply unit ( 1 ) is operable in a master mode (S4), in which the supply unit ( 1 ) the main supply of the bus ( 3 ) or in a slave mode (S3) is operable in which the supply unit ( 1 ) an auxiliary supply of the bus ( 3 ) is as needed and depending on the detected current drain from the bus ( 3 ) the supply unit ( 1 ) in the master mode (S4) or in the slave mode (S3) is operable. Supply unit ( 1 ) according to one of claims 2 to 4, wherein the DC voltage is applied to the bus ( 3 ) is provided when the short-circuit switch ( 5 ) is switched to the second switching state (II). Supply unit ( 1 ) according to one of the preceding claims, wherein the circuit is set up to compare the currently detected current drain with the predetermined value (I _x ) of the maximum current drain, wherein when the predetermined value (I _x ) is exceeded, the supply unit ( 1 ) in master mode (S4). Supply unit ( 1 ) according to one of claims 2 to 6, wherein the control unit ( 1 ) is configured to capture the current current consumption only after the expiration of an individual random waiting time (T _random ). Power supply system (C) for a bus at rest ( 3 ), whereby a maximum current drain (I _x ) from the bus ( 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ) is limited to a predetermined value, comprising at least two parallel to the bus ( 3 ) connected supply units ( 1 ) according to one of claims 1 to 7, wherein each of the supply units ( 1 ) is designed to allow bus subscribers ( 8th . 8th' . 8th'' . 8th''' ) by means of the bus ( 3 ) with a DC voltage, each of the supply units ( 1 ) has a circuit which is set up, the current current consumption from the bus ( 3 ) by shorting the bus ( 3 ) and where the supply units ( 1 ) Short circuit the bus selectively to capture the current current drain. Power supply system (C) according to claim 8 for a lighting system (A), wherein at least one bus subscriber ( 8th . 8th' . 8th'' . 8th''' ) is an element in the lighting system (A) and wherein the bus ( 3 ) a DALI standardized bus ( 3 ) of the illumination system (A). Power supply system (C) according to one of claims 8 or 9, wherein each of the supply units ( 1 ) (In an initialization phase S1) an individual random waiting time (T _randomly) waits before the circuit (the current current draw of the bus 3 ) detected. Power supply system (C) according to one of claims 8 to 10, wherein based on a comparison (S2) between the currently detected current consumption and the predetermined value of the maximum current drain (I _x ) from the bus ( 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ) in each supply unit ( 1 ), which of the supply units ( 1 ) is operated as a main supply or auxiliary supply in the power supply system. Power supply system (C) according to claim 11, wherein only after the expiry of a preset start delay time (T _switch-on ) in the initialization phase (S1) the supply units ( 1 ) is operated as a main supply unit or auxiliary supply unit. Method for operating a power supply system (C) according to one of the preceding claims 8 to 12 with the method steps: - initializing (S1) of the power supply system (C), in which in each supply unit ( 1 ) the power supply system (C) waits for an individual random waiting time (T _random ) (S14); Detecting (S2) a current current consumption from the bus ( 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ) by selectively short-circuiting (S12) the bus ( 3 ) of each supply unit ( 1 ); - operating the respective supply unit ( 1 ) either in a master mode (S4) or in a slave mode (S3), wherein the mode (S3, S4) depends on the currently detected current drain from the bus (S4) 3 ) is selected; and - checking (S5) a time period in which the bus ( 3 ) is short-circuited, wherein when a maximum short-circuit time (T _x ) is exceeded, the process is restarted. Method according to claim 13, wherein the detection (S2) is carried out by means of a control unit ( 4 ) in the respective supply unit ( 1 ), which makes the bus ( 3 ) by means of a short-circuit switch ( 5 ) (S12), whereby due to the random waiting time only one of the power supply units ( 1 ) of the lighting system ( 1 ) the current current drain through the power supply lines ( 3 ) detected. Method according to one of Claims 13 or 14, the detection (S2) taking place (S22) after the supply unit ( 1 ) a DC voltage for the bus ( 3 ), wherein when the predetermined value of the maximum current drain is exceeded, the detecting supply unit ( 1 ) its DC power supply for the bus ( 3 ) is disabled (S23). The method according to claim 15, wherein the detection (S2) takes place again (S24) after the supply unit detecting the current drain ( 1 ) a DC voltage for the bus ( 3 ) has disabled (S23). Method according to one of claims 13 to 16, wherein for the operation of a supply unit ( 1 ) in the slave mode (S3) the following method steps are provided: - detecting (S33) a voltage value on the bus ( 3 ) by the supply unit ( 1 ); - Recapture (S37) the current current drain from the bus ( 3 ) only in the event that the detected voltage value is above a reference voltage value (U _x ); and - operating the supply unit ( 1 ) in the master mode (S4) in the event that the re-detection (S37) shows that the currently detected current consumption above a predetermined value of a maximum current drain (I _x ) from the bus (S37) 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ). Method according to claim 17, wherein for the operation of the supply unit ( 1 ) in the slave mode (S3) the following further method steps are provided: - Waiting (S39) a master mode waiting time (T _master ) for the case that the re-detection (S37) shows that the current detected current consumption below a predetermined Value of a maximum current drain (I _x ) from the bus ( 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ); and - recapture the voltage value on the bus ( 3 ), this supply unit ( 1 ) is turned off when the recapture of the voltage value indicates that the recaptured voltage value is below the reference voltage value (U _x ). Method according to one of claims 13 to 18, wherein for the operation of a supply unit ( 1 ) in the master mode (S4) the following method steps are provided: - waiting (S41) a master mode waiting time (T _master ); - Recapture (S43) the current current drain from the bus ( 3 ); and - canceling (S44) the short circuit of the bus ( 3 ) in the event that the re-detection (S43) shows that the detected current current consumption below a predetermined value of a maximum current drain (I _x ) from the bus (S43) 3 ) by bus users ( 8th . 8th' . 8th'' . 8th''' ). The method of claim 19, wherein for operating a supply unit ( 1 ) in the master mode (S4), the following further method steps are provided: - detecting (S46) a voltage value on the bus ( 3 ); - waiting (S47) a random wait time (T _random ) in case the detection (S46) shows that the detected voltage value is above a reference voltage value (U _x ); Short circuiting (S48) the bus ( 3 ); and - Recapturing (S49) the current current consumption from the bus (S49) 3 ).

Images