WO2014172724A1

WO2014172724A1 - Capacitor power supply unit for supplying a small electrical consumer

Info

Publication number: WO2014172724A1
Application number: PCT/AT2014/000082
Authority: WO
Inventors: Josef FILZMAIER; Peter Duracher
Original assignee: HELLA Sonnen- und Wetterschutztechnik GmbH
Priority date: 2013-04-26
Filing date: 2014-04-25
Publication date: 2014-10-30
Also published as: AT514268B1; AT514268A1

Abstract

A circuit (1) for supplying energy to electrical consumers, said circuit comprising an energy accumulator (4) which preferably comprises a storage capacitor and which is connected to a pole of the direct voltage output of a rectifier (3), and a serial power supply capacitor (2) which is connected to an alternating current input of said rectifier (3), a switching element (7) being provided which is controlled by means of a measurement controller (6) and which by-passes the alternating current input, the direct current output or a diode of the rectifier (3) depending on the voltage at the energy accumulator (4).

Description

CAPACITOR POWER SUPPLY FOR SUPPLYING AN ELECTRICAL

SMALL CONSUMER

The invention relates to a circuit according to the preamble of claim 1. In this case, a method is used, which controls the removal of energy from the (public) network demand-dependent in load fluctuations, i. returns again if it is not needed.

Electronic circuits for building automation are increasingly indispensable in modern buildings or homes, for example, to be able to conveniently control the operation of all electrical equipment inside and outside of buildings. Local operation by switching or manual adjustment of the respective device is due to the ever-increasing collection of modern control systems in the living room no longer up to date. However, when modern networked control systems are used for facilities, they usually also require connection to the public power grid, both in terms of permanent communication and remote maintenance. In particular, the high number of distributed electronic devices in the building unnecessarily increases energy consumption (hidden consumers), making such "smart" building control systems unattractive to low-energy or passive houses.

To connect a low-power electronic device to the public network, you will need a low-power power supply in the future, a "zero-power power supply", so to speak.These electronic devices are usually control devices which, if required, electrically insulate the shading bring the desired position, turn lights on or off, open or close windows or move ingeniously all equipment inside and outside buildings via electric drives If this control unit consumes little power, then the associated power supply only needs an isolating transformer

(Own power typically 3 to 5 watts), if a galvanic separation is required for safety reasons. If not, a capacitive power supply, which is state of the art and thus already available on the market, is usually sufficient. Are in it In principle, two capacitors connected in series via a rectifier, resulting in a capacitive voltage division. Because of the 90 ° phase shift between current and voltage, the suitable for this purpose series network capacitor generates no power loss, only reactive power. However, with each half cycle, the capacitor is recharged after the rectifier, which causes the voltage at this steadily increase when no electrical energy is removed from the capacitor. Therefore, a voltage limitation, for example: VDR or Zener diode, required, which naturally leads to losses in the form of heat. Thus, it is a lossy power supply.

The present invention is therefore an object of the invention to provide a lossless or low-loss power supply (especially power supply) for electrical consumers. Above all, this should partially or substantially completely return the electrical energy taken from the (public) network and thus reduce the power loss almost to zero. One could therefore speak in the broadest sense of a "zero-power power supply".

This is achieved according to the invention by the features of claim 1. Advantageous embodiments are the subject of the dependent claims.

The prior art is based on the general idea to charge a storage capacitor via the public grid through a capacitive series resistor via a bridge rectifier. The voltage level at the storage capacitor is limited by an overvoltage element, whereby electrical energy is converted into heat, which leads to losses in the power supply.

In order to minimize these losses in the power supply, it must be ensured that the energy taken from the network is returned to the network, if this is not needed. As a result, load-dependent energy extraction is essentially possible from 0 to 100%. For this purpose, the two diode paths of the bridge rectifier must be short-circuited for the positive as well as for the negative half-wave via a switch. In the case of a short circuit, the electrical energy consumed in a net quarter period becomes as follows Net quarter period again essentially completely returned to the network. If the short circuit between the two AC voltage terminals of the bridge rectifier, so the rectifier losses are also eliminated. In the event that only two load cases are present (standby and active), a balanced energy balance in the energy storage must be provided (eg: capacitor, battery, ...), ie the supplied electrical energy must be equal to the removed. Since electronic control systems are mostly in standby, the power supply can be designed for this standby power. Nevertheless, for a short time, the controller must perform activities as needed. For this activity, more electrical energy is needed for the electronic circuit for a short time. In the case of capacitive power supplies already available on the market, this short-term higher energy extraction is used as the basis for the power balance, whereby most of the time (standby) the remaining "excess energy" in the power supply has to be consumed, which leads to losses in the power supply.

In order not to generate any "excess energy" in particular, the bridge rectifier is specifically operated, ie either in half or full wave rectification, with energy being supplied from the network to the energy store in the full wave rectification in both half cycles

Half-wave and full-wave rectification takes place via a switching element which, depending on need, short-circuits a diode of the bridge rectifier in the negative half-wave. The energy removal from the power supply is monitored while the switching element is controlled so that the transition between the two rectifier principles is continuous. With this method, a load-dependent energy extraction is essentially possible between 50 and 100%, which reduces the power loss in the power supply.

A further advantageous embodiment of the solution according to the invention is the development of a simple integrated circuit (IC), since no electronic special components are required for this structure. In addition, the IC can be designed by the simple and proven process of all digital circuits which can then be made available for the construction of "Green Elektronik".

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

1 shows a block diagram of the power supply according to the invention with load-dependent energy extraction essentially from 0 to 100%,

2 is a block diagram of the power supply according to the invention with load-dependent energy extraction substantially from 50 to 100%,

3 is a block diagram of the power supply according to the invention with a switching element at the AC voltage input,

4 shows a block diagram of the power supply according to the invention with a block representation of the measurement controller and a switching element at the DC output,

5 is a block diagram of the power supply according to the invention with a block diagram of the measuring controller and a switching element at the AC voltage input, Fig. 6 is a block diagram of the measuring controller and

Fig. 7 is a block diagram of the power supply according to the invention with a Äbleitwiderstand and a block diagram of the measurement controller. According to the embodiment illustrated in FIG. 1, the circuit 1 according to the invention has a capacitive current limit 2, a rectifier 3 designed as a bridge rectifier in this embodiment, and an energy store 4 designed as a storage capacitor. The electrical energy will delivered via this capacitive voltage divider in the energy storage 4, which can then be removed via a coupled consumer. In the event that little to no energy is taken from the energy store 4, be it due to a lack of consumers or standby mode of the consumer, the voltage on the energy store 4 designed as a storage capacitor would rise steadily. However, this overvoltage is detected by the measuring controller 6, whereupon the latter then executes the electronic switch designed as a switching element 7 correspondingly long the rectifier 3 at the output. Thus, the electrical energy extracted in the previous power quarter period is completely returned to the network in the following power quarter period. If electrical energy is actually required, the switching element 7 opens on the measuring controller 6 as required, and the rectifier 3 again supplies energy to the energy store 4. In this variant, the overvoltage element 5 assumes a purely protective function and no power loss will occur therein. With this circuit 1, the (public) network taken electrical energy is returned as needed.

According to the exemplary embodiment shown in FIG. 2, the circuit 1 according to the invention has a capacitive current limiting device 2, a rectifier 3 designed as a bridge rectifier, and an energy store 4 designed as a storage capacitor. The electrical energy is supplied via this capacitive voltage divider in the energy storage 4, which can then be removed for example via a coupled consumer. In the event of an excess energy occurring at the energy store 4, which is indicated by an increased voltage across the storage capacitor, this overvoltage is dissipated at the overvoltage element 5. If the measuring controller 6 recognizes that more energy is taken from the energy store 4, then the switching element 7 designed as an electronic switch is opened and thus switched to full-wave rectification, whereby more energy from the network enters the energy store 4. If the energy removal goes back, the measuring controller 6 closes the switching element 7 and thus switches to half-wave rectification, as a result of which the energy store 4 is only recharged in half a network period. In particular, there is a continuous switching between half and full wave rectification, which also comes very close to the energy extraction from the public network. In the embodiment of the circuit 1 shown in Fig. 3, the short-circuiting carried out as electronically controlled switch element 7 takes place at the AC voltage input of the rectifier 3 designed as a bridge rectifier. By short-circuiting the input of the rectifier 3, the losses on the rectifier 3 can be additionally eliminated ,

According to the embodiment shown in FIG. 4, the circuit 1 according to the invention comprises a damped inductive component designed as a damped coil 8, a switching element 7 designed as an electronically controlled changeover switch at the DC output of the rectifier 3 designed as a bridge rectifier, and an energy store configured as a storage capacitor 4 on. Due to the design of the switching element 7 as an electronically controlled changeover switch, the energy storage 4 in the preceding embodiments in series upstream diode D2 omitted. Thus, a simpler circuit and a further reduction of power loss can be achieved. The damped coil 8 is used to limit the current inrush current and to filter transient mains voltage spikes. The internal structure of the measuring controller 6 is shown schematically in FIG. 4 as a block diagram, this includes the switching blocks for the

Supply voltage a, the reference voltage b, the control voltage c, the synchronization d, the triangle generator e and the pulse width modulator f. The controlled by the measuring controller 6 via a pulse width modulated signal switching element 7 can be controlled with variable pulse durations and pulse frequencies, and it is also possible within a network period, the switching element 7 to control several consecutive times and thereby short-circuit the rectifier 3 at the output. One can speak of an energy return control, which can be improved in that within a network period, the removal and return takes place six times, and not as in the classic rectifier circuits, always in the voltage vertex, the energy from the

Remove network, which leads to peak loads in the public network. 5 shows an embodiment of the circuit 1 with a damped coil 8, a capacitive current limit 2, a switching element 7 designed as an electronically controlled switch at the AC voltage input of the rectifier 3 designed as a bridge rectifier, and an energy store 4 designed as a storage capacitor. The internal structure of the measuring controller 6 is shown schematically as a block diagram. Here, too, the losses at the rectifier 3 can be additionally eliminated by short-circuiting the AC voltage input of the rectifier 3. In Fig. 6, the internal structure of the measuring controller 6 is shown schematically as a block diagram, this includes the switching blocks for the supply voltage a, the reference voltage b, the control voltage c, the synchronization d, the triangular generator e and the pulse width modulator f. The pulse width modulator f is controlled by the triangular generator e, wherein this can also be done in a network-synchronous manner.

In Fig. 7 is a block diagram of the power supply according to the invention with a damped coil 8, a capacitive current limiting 2, designed as an electronically controlled switch element 7 at the AC voltage input of the bridge rectifier rectifier 3, designed as a storage capacitor energy storage 4, a bleeder 9 and a Block representation of the measuring controller 6 shown. The discharge resistor 9, which is connected to the line-side pole of the capacitive current limiting 2, stands at the other terminal in connection with the switching block of the synchronization d of the measuring controller 6, as well as galvanically in connection with the DC output of the rectifier 3, which is designed as a bridge rectifier 3. and is thus connected substantially parallel to the capacitive current limit 2. It can thereby be ensured that the capacitive current limit 2 is rapidly discharged by the bleeder resistor 9 after disconnecting the connection of the circuit 1 from the grid. In addition, the fact that the line-side pole of the capacitive current limiting 2 via the bleeder resistor 9 is electrically connected to the DC voltage output of the rectifier 3 - and thus with the switching block of the supply voltage a of the measuring controller 6 -, the measuring controller during operation partially supplied via this circuit branch become. Thus, the Circuit efficiency will be further increased and more energy will be provided to the consumer. In the case of a switching element 7 embodied as an electronically controlled changeover switch at the DC output of the rectifier 3 (not shown), it must of course be ensured that, after disconnecting the circuit 1 from the mains, the switching element 7 is in a position or is brought into a position, so that the bleeder resistor 9 is connected substantially parallel to the capacitive current limit 2.

Claims

claims

Circuit (1) for supplying energy to electrical consumers, comprising:

an energy store (4), preferably comprising a storage capacitor, which is connected to a pole of the DC output of a rectifier (3),

- A series network capacitor (2) which is connected to an AC voltage input of the rectifier (3), characterized in that a switching element (7) is provided, which is controlled by a measuring controller (6) and which depends on the voltage at the energy store (4 3), the DC voltage output (FIG. 1) or a diode (FIG. 2) of the rectifier (3).

A circuit according to claim 1, characterized in that the switching element (7) is parallel to the AC voltage input or the DC voltage output of the rectifier (3).

A circuit according to claim 1 or 2, characterized in that the rectifier (3) is designed as a bridge rectifier.

Circuit according to one of claims 1 to 3, characterized in that the energy store (4) via a diode (D2) is connected to the pole of the DC voltage output of the rectifier (3).

Circuit according to one of claims 1 to 4, characterized in that the circuit (1) is designed as a power supply for an electrical load.

Circuit according to one of claims 1 to 5, characterized in that, depending on the energy extraction from the energy store (4), measured via the measuring controller (6), the switching element (7) is driven so that the recorded electrical energy of a Netzviertelperiode in the following Net quarter period is returned to the electrical network, if it is not taken from a connected consumer from the energy storage (4). 7. A circuit according to one of claims 1 to 6, characterized in that, depending on the energy extraction from the energy store (4), measured via the measuring controller (6), the switching element (7) is driven so that the absorbed electrical energy exclusively in the positive or negative Netzviertelperiode in the following positive or negative network quarter period is returned to the electrical network, if it is not taken from a connected consumer from the energy storage (4).

Circuit according to one of claims 1 to 7, characterized in that the removal and return of the electrical energy takes place several times in the network period to prevent peak loads in the network.

Circuit according to one of claims 1 to 8, characterized in that via the measuring controller (6), the minimum or maximum energy extraction from the energy storage (4) is detected and thereby the rectifier via the switching element (7) switches between half and full wave rectification.

10. A circuit according to any one of claims 1 to 9, characterized in that the load or demand-dependent continuous switching between half and full wave rectification takes place.

1 1. Circuit according to claim 1 to 10, characterized in that the switching element (7) has at least one electronic switch.

Circuit according to one of Claims 1 to 11, characterized in that a damped inductive component, preferably a coil (8), is provided to limit the inrush current and to filter transient mains voltage peaks.

13. A circuit according to any one of claims 1 to 12, characterized in that the measuring controller (6) constructed of supply voltage (a), reference voltage (b), control voltage (c), synchronization (d), triangular generator (s) and pulse width modulator (f ) controls the switching element (7). 4. A circuit according to any one of claims 1 to 13, characterized in that the measuring controller (6) controls the switching element (7) via a pulse width modulated signal.

15. A circuit according to claim 13, characterized in that the measuring controller (6) for controlling the pulse width modulator (f) one of the triangular generator (e) generated signal having a frequency which is a multiple of the mains frequency - preferably 300Hz - used.

Circuit according to one of Claims 1 to 15, characterized in that a bleeder resistor (9) is connected at one connection to the line-side pole of the series-network capacitor (2) and galvanically connected to the other connection to one pole of the DC output of a rectifier (3) Connection stands.

Circuit according to one of Claims 1 to 16, characterized in that the measuring controller (6) is supplied with energy from the line-side pole of the series-network capacitor (2), preferably via a line having at least one resistor (R2).