CN212752135U

CN212752135U - Isolated KNX power supply

Info

Publication number: CN212752135U
Application number: CN202021434028.3U
Authority: CN
Inventors: 周春喜
Original assignee: Hangzhou Shendu Technology Co ltd
Current assignee: Hangzhou Shendu Technology Co ltd
Priority date: 2020-07-20
Filing date: 2020-07-20
Publication date: 2021-03-19
Anticipated expiration: 2030-07-20

Abstract

The utility model relates to an isolated KNX power supply, including switching power supply unit, KNX bus power supply unit and auxiliary power supply unit, switching power supply unit is used for converting the mains voltage into first voltage and second voltage, and supply power for KNX bus power supply unit and auxiliary power supply unit respectively, KNX bus power supply unit includes power isolation circuit and choke unit, power isolation circuit passes through at least one bus device of KNX bus electricity connection, wherein, power isolation circuit is used for converting first voltage into the third voltage that supplies bus device communication, and/or, with third voltage and the second voltage isolation; the choke unit is used for suppressing a common-mode interference signal of the power isolation circuit. Through the application, the problem that the isolation circuit is not arranged between the output port of the isolation type KNX power supply and the KNX bus to easily interfere with communication of bus equipment is solved, and the beneficial effect that power supply and communication are not interfered mutually is achieved.

Description

Isolated KNX power supply

Technical Field

The utility model relates to a switching power supply technical field especially relates to isolated form KNX power.

Background

In an intelligent KNX control system, an induction terminal (such as a switch panel, a sensor, a touch screen and the like) and an actuator (such as a switch actuator, a dimming actuator, a curtain actuator, a fan coil actuator and the like) are generally connected through a bus, a controller is installed at an indoor corresponding position, the actuator is installed in a distribution box, so that strong current and weak current can be separated, and strong current wires are uniformly wired into the distribution box for centralized control.

In an existing KNX control system, a KNX power supply is used to provide an operating power supply for controlling a plurality of bus devices (induction terminals and/or actuators) to operate, and at the same time, the KNX power supply also controls all the bus devices accessing the KNX control system, for example: the KNX power supply controls the switch panel of the lighting equipment to work through the KNX bus, so that the lighting equipment is turned on or turned off for lighting. However, the existing KNX power supply usually converts the voltage of the utility grid into a direct current voltage, and then supplies power to the bus device, an isolation circuit is not arranged between an output port of the KNX power supply and the KNX bus, a certain spike pulse and a certain miscellaneous sequence signal exist in the direct current voltage converted by the voltage of the utility grid, and when the converted direct current voltage is directly used for supplying power to the bus device, the spike pulse and the miscellaneous sequence signal can be connected into the bus in series to cause interference on communication of the bus device, so that the control of the KNX control system is influenced.

In the related art, no effective solution is provided for the problem that an isolation circuit is not arranged between an output port of a KNX power supply and a KNX bus and the communication of bus equipment is easy to interfere.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an isolated KNX power supply to at least solve the problem that bus equipment communication is easily interfered by an isolating circuit which is not arranged between an output port of the KNX power supply and a KNX bus in the related art.

In a first aspect, an embodiment of the present application provides an isolated KNX power supply, including: the utility model discloses a power supply unit, the utility grid is connected to switching power supply unit, KNX bus power supply unit and auxiliary power supply unit, the utility grid is connected to switching power supply unit's input electricity, switching power supply unit's output electricity is connected the KNX bus power supply unit with auxiliary power supply unit, switching power supply unit is used for converting utility grid voltage into first voltage and second voltage, and be the KNX bus power supply unit with the auxiliary power supply unit power supply respectively, the KNX bus power supply unit includes power isolation circuit and choke unit, power isolation circuit includes first power supply port and second power supply port, choke unit includes third port and fourth port, first power supply port respectively with switching power supply unit's first positive output end with the third port electricity is connected, the second power supply port with fourth port electricity is connected, the second power supply port still connects at least one bus equipment through the KNX bus electricity, wherein the power isolation circuit is configured to convert the first voltage to a third voltage for communication by the bus device and/or to isolate the third voltage from the second voltage; the choke unit is used for suppressing a common-mode interference signal of the power isolation circuit.

In some embodiments, the power isolation circuit includes a first isolation circuit, a second isolation circuit and a first voltage regulator tube, two ends of the first isolation circuit are electrically connected with the first power supply port and the second power supply port respectively, two ends of the second isolation circuit are electrically connected with a first power supply and a second power supply respectively, and the second power supply port is further electrically connected with the second power supply through the first voltage regulator tube; the first isolation circuit comprises a first current-limiting resistor, a first switch tube, a first resistor and a second voltage-stabilizing tube, wherein the first switch tube comprises a first control end, a first input end and a first output end, one end of the first current-limiting resistor is connected with the first power supply port, one end of the first resistor and the anode of the second voltage-stabilizing tube, the other end of the first current-limiting resistor is connected with the first control end, the first input end is connected with the cathode of the second voltage-stabilizing tube, and the first output end is connected with the other end of the first resistor and the second power supply port; the second isolation circuit comprises a second current-limiting resistor, a second switch tube, a second resistor and a third voltage-stabilizing tube, the second switch tube comprises a second control end, a second input end and a second output end, one end of the second current-limiting resistor is connected with the second power supply, the anode of the first voltage-stabilizing tube, the anode of the third voltage-stabilizing tube and one end of the second resistor, the other end of the second current-limiting resistor is connected with the second control end, the second input end is connected with the cathode of the third voltage-stabilizing tube, and the second output end is connected with the other end of the second resistor and the first power supply.

In some embodiments, the choke unit includes a two-wire inductor, a first rectifier, a third resistor, and a fourth resistor, wherein the two-wire inductor includes a fifth port, a sixth port, a seventh port, an eighth port, a ninth port, and a tenth port, the third rectifier includes a third control terminal, a third input terminal, and a third output terminal, the fifth port connects the first power supply port and the third port, the sixth port connects the second power supply port and the fourth port, the seventh port connects a second power supply, the eighth port connects a first power supply, the ninth port connects an anode of the first rectifier and one end of the third resistor, a cathode of the first rectifier connects the third output terminal, and the other end of the third resistor connects the third control terminal, the third output end is connected with one end of the fourth resistor, and the other end of the fourth resistor is connected with the tenth port.

In some of these embodiments, the switching power supply unit includes: the rectification circuit is used for rectifying alternating-current voltage input by the commercial power grid into fourth voltage; the inverter comprises a primary winding, a first secondary winding, a second secondary winding and an auxiliary winding, wherein the first secondary winding is connected with the first positive output end through a first output rectifying circuit, and the second secondary winding is connected with the second positive output end of the switching power supply unit through a second output rectifying circuit; the main control circuit comprises a switching power supply chip, the switching power supply chip comprises a fourth input end, a fourth control end and a first feedback end, the fourth input end is respectively connected with the rectifying circuit and the auxiliary winding through an online voltage detection circuit and a first power supply circuit, the fourth control end is connected with the primary winding, and the first feedback end is connected with the first secondary winding through a voltage negative feedback circuit; the rectifier circuit provides a power supply for starting the switching power supply chip, the auxiliary winding provides a working power supply for starting the switching power supply chip, the switching power supply chip acquires a change signal reflecting the output voltage of the first output rectifier circuit through the voltage negative feedback circuit, the inverter is controlled to convert the fourth voltage into an inverted voltage, and the inverted voltage is rectified into the first voltage and the second voltage through the first output rectifier circuit and the second output rectifier circuit respectively.

In some of the embodiments, the switching power supply chip comprises a TOP271E switching power supply chip.

In some embodiments, the rectifier circuit includes an electromagnetic filter circuit and an input rectifier circuit connected in sequence, an input end of the electromagnetic filter circuit is connected to a utility grid, an output end of the electromagnetic filter circuit is electrically connected to an input end of the input rectifier circuit, and an output end of the input rectifier circuit is connected to the primary winding, where the electromagnetic filter circuit is configured to filter a voltage of the utility grid into a first ac voltage, and the input rectifier circuit is configured to rectify the first ac voltage into the fourth voltage.

In some embodiments, the electromagnetic filter circuit includes a first voltage dependent resistor, a first filter capacitor and an EMI inductor, the first voltage dependent resistor and the first filter capacitor are connected in parallel, electrical connection points of the first voltage dependent resistor and the first filter capacitor are respectively connected with two input ends of a utility grid and the EMI inductor, and two output ends of the EMI inductor are connected with input ends of the input rectification circuit; the input rectifying circuit comprises a rectifying bridge and a first thermistor, two input ends of the rectifying bridge are respectively connected with two output ends of the EMI inductor, one of the two output ends of the rectifying bridge is connected with the first thermistor in series and is connected with the same-name end of the primary winding, and the other of the two output ends of the rectifying bridge is connected with a third power supply.

In some embodiments, the online voltage detection circuit comprises a plurality of third current-limiting resistors connected in series, one end of the plurality of current-limiting resistors connected in series is connected to the same-name end of the primary winding, and the other end of the plurality of current-limiting resistors connected in series is connected to the fourth input end;

the first power supply circuit comprises a second rectifier tube, a third rectifier tube, a fourth voltage-stabilizing tube and a fourth current-limiting resistor, wherein the anode of the second rectifier tube is connected with the unlike end of the auxiliary winding, the cathode of the second rectifier tube is connected with the anode of the third rectifier tube, the cathode of the third rectifier tube is connected with the anode of the fourth voltage-stabilizing tube, the cathode of the fourth voltage-stabilizing tube is connected with the fourth current-limiting resistor, and the fourth current-limiting resistor is further connected with the fourth input end.

In some embodiments, the first output rectifying circuit and the second output rectifying circuit each include a fourth rectifying tube, an anode of the fourth rectifying tube is connected to the different name end of the first secondary winding or the second secondary winding, a cathode of the fourth rectifying tube is connected to the first positive output end or the second positive output end through an LC-pi filter circuit including a first filter inductor and two first filter capacitors, at least one second filter capacitor for eliminating ripples is further disposed between the LC-pi filter circuit and the first positive output end or the second positive output end, and the fourth rectifying tube is further connected in parallel to an RC absorption network including a fifth resistor and a third filter capacitor for absorbing spike pulses.

In some embodiments, the voltage negative feedback circuit includes a controllable precise voltage regulator element, an optocoupler and a peripheral resistor capacitor, a voltage reference electrode of the controllable precise voltage regulator element is connected with the first positive output end by connecting a first sampling resistor in series and is connected with a first power supply by connecting a first pull-down resistor in series, a cathode of a light emitter of the optocoupler is connected with a cathode of the controllable precise voltage regulator element, an anode of the light emitter is connected with a cathode of the fourth rectifier tube of the first output rectifier circuit by connecting a sixth resistor in series, a first isolation resistor is connected between the cathode and the anode of the light emitter of the optocoupler in series, and a collector of a light receiver of the optocoupler is connected with a first coupling resistor in series and is connected with the first feedback end; the voltage negative feedback circuit samples the output voltage of the first output rectifying circuit and feeds back voltage change to the switching power supply chip, and the switching power supply chip controls the inverter to convert the fourth voltage rectified by the rectifying circuit into the inversion voltage according to the voltage change.

Compared with the related art, the isolated KNX power supply provided by the embodiment of the application comprises a switching power supply unit, a KNX bus power supply unit and an auxiliary power supply unit, wherein an input end of the switching power supply unit is electrically connected with a mains grid, an output end of the switching power supply unit is electrically connected with the KNX bus power supply unit and the auxiliary power supply unit, the switching power supply unit is used for converting voltage of the mains grid into a first voltage and a second voltage and respectively supplying power to the KNX bus power supply unit and the auxiliary power supply unit, the KNX bus power supply unit comprises a power isolation circuit and a choke unit, the power isolation circuit comprises a first power supply port and a second power supply port, the choke unit comprises a third port and a fourth port, the first power supply port is respectively and electrically connected with a first positive output end and a third port of the switching power supply unit, the second power supply port is electrically connected with a fourth port, and the second power supply port is also electrically connected, the power isolation circuit is used for converting the first voltage into a third voltage for the bus equipment to communicate with and/or isolating the third voltage from the second voltage; the choke unit is used for suppressing common-mode interference signals of the power isolation circuit. Through the isolated KNX power supply of this embodiment, solved the problem that does not set up the easy interference bus equipment communication of isolating circuit between the output port of isolated KNX power supply and the KNX bus, realized through power isolation circuit and choking unit with the second voltage of switching power supply unit output with supply the third voltage of bus equipment work isolation, the power supply with the mutual noninterference's of communication beneficial effect.

The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below to provide a more thorough understanding of the application.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

fig. 1 is a circuit schematic of an isolated KNX power supply according to an embodiment of the present invention;

fig. 2 is a schematic circuit diagram of a KNX bus power supply unit according to an embodiment of the present invention;

fig. 3 is a schematic circuit diagram of a switching power supply unit according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided in the present application without any inventive step are within the scope of protection of the present application.

It is obvious that the drawings in the following description are only examples or embodiments of the present application, and that it is also possible for a person skilled in the art to apply the present application to other similar contexts on the basis of these drawings without inventive effort. Moreover, it should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of ordinary skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments without conflict.

Unless defined otherwise, technical or scientific terms referred to herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this application belongs. Reference to "a," "an," "the," and similar words throughout this application are not to be construed as limiting in number, and may refer to the singular or the plural. The present application is directed to the use of the terms "including," "comprising," "having," and any variations thereof, which are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in this application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The term "plurality" as referred to herein means two or more. "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. Reference herein to the terms "first," "second," "third," and the like, are merely to distinguish similar objects and do not denote a particular ordering for the objects.

The embodiment provides an isolated KNX power supply. Fig. 1 is a schematic circuit diagram of an isolated KNX power supply according to an embodiment of the present invention. As shown in fig. 1, the isolated KNX power supply includes: the switch power supply unit 100, the KNX BUS power supply unit 200 and the auxiliary power supply unit, the input end of the switch power supply unit 100 is electrically connected to the utility grid (the utility grid provides 195V-255V of alternating voltage), the output end of the switch power supply unit 100 is electrically connected to the KNX BUS power supply unit 200 and the auxiliary power supply unit, the switch power supply unit 100 is used for converting the utility grid voltage into a first voltage V _ BUS and a second voltage V2, and respectively supplies power to the KNX BUS power supply unit 200 and the auxiliary power supply unit, the KNX BUS power supply unit 200 comprises a power isolation circuit 300 and a choke unit 400, the power isolation circuit 300 comprises a first power supply port (connected with the first voltage V _ BUS) and a second power supply port connected with a third voltage BUS +, the choke unit 400 comprises a third port (connected with the first voltage V _ BUS) and a fourth port (connected with the third voltage BUS +), the first power supply port is respectively connected with the first positive output end (corresponding to the first voltage V _ BUS) and the third port of the switch power supply unit The second power supply port is electrically connected with the fourth port, and the second power supply port is further electrically connected with at least one BUS device through a KNX BUS, wherein the power isolation circuit 300 is used for converting the first voltage V _ BUS into a third voltage BUS + for the BUS device to communicate with, and/or isolating the third voltage BUS + from the second voltage V2; the choke unit 400 is used to suppress the interference signal of the power isolation circuit 300.

In this embodiment, the second voltage V-BUS output by the switching power supply unit 100 is isolated from the third voltage BUS + for the BUS device to work by the power isolation circuit 300 and the choke unit 400, so that the problem that the isolated KNX power supply is not provided with an isolation circuit between the output port and the KNX BUS, which is prone to interfere with the communication of the BUS device, is solved, and the beneficial effects of mutual noninterference of power supply and communication are achieved.

It should be noted that, when the KNX BUS power supply unit 200 composed of the power isolation circuit 300 and the choke unit 400 supplies power to the KNX BUS device, the power isolation circuit 300 couples interference signals such as spike pulses and mixed sequence signals in the dc voltage (including the first voltage V _ BUS and the second voltage V2) output by the switching power supply unit 100, so that the third voltage BUS + output by the KNX BUS power supply unit 200 does not contain interference signals, and thus does not affect the communication of the KNX BUS device connected to the isolated KNX power supply, and the isolation function is implemented. Meanwhile, when the BUS device needs additional power supply, the voltage output by the auxiliary power supply unit, namely the second voltage V2, is isolated from the BUS voltage (corresponding to the third voltage BUS +) of the BUS device, so that the BUS power supply cannot be affected by the additional power supply.

It should be noted that the first power supply port, the first positive output end and the third port are electrically connected and are all represented by a network reference number V _ BUS, that is, the first positive output end of the switching power supply unit 100 corresponds to the input ends (the first power supply port and the third port) of the power isolation circuit 300 and the choke unit 400; the second power supply port and the fourth port are electrically connected and are both indicated by a BUS + network reference number, that is, the power isolation circuit 300 and the output terminal (the first power supply port and the third port) of the choke unit 400 are correspondingly connected. It should be noted that in this embodiment, the input voltage and the output voltage of the auxiliary power supply unit are both the second voltage V2 output by the switching power supply unit 100, the auxiliary power supply unit in this embodiment of the present application is one auxiliary output of the switching power supply unit 100, and when the bus device needs to supply power additionally, the bus device is powered by the auxiliary output.

The power isolation circuit 300 of the embodiment of the present application also isolates the first voltage V _ BUS output by the switching power supply unit 100 from the third voltage BUS +, and at the same time, the first voltage V _ BUS is isolated from the third voltage BUS +, and at the same time, the second voltage V2 output by the switching power supply unit 100 is supplying power for the BUS device that needs additional power supply, because the BUS device is connected to the KNX BUS supplied by the third voltage BUS +, therefore, the power isolation power supply 300 also isolates the second voltage V2 from the third voltage BUS +.

The choke unit 400 in this embodiment is a built-in choke, and is mainly used to isolate interference between power supply and communication of the bus, and through the choke, an interference signal of the power isolation circuit is suppressed, so as to prevent the interference signal from entering the bus to affect communication of the bus device, and the interference signal suppressed by the choke includes a common mode signal.

The switching power supply unit 100 in the embodiment of the present application includes, but is not limited to, a flyback switching power supply or a forward switching power supply, and according to the disclosure of the present application, a person skilled in the art may easily think of modifying the switching power supply unit 100 disclosed in the present application into a switching power supply adapted to an excitation form of the switching power supply according to a specific selection of an excitation mode, so that the present application may be implemented in both a flyback switching power supply and a forward switching power supply, and the embodiments of the present application are not limited thereto.

Fig. 2 is a schematic circuit diagram of a KNX BUS power supply unit according to an embodiment of the present invention, as shown in fig. 2, in some embodiments, in order to convert the first voltage V _ BUS into a third voltage BUS + and isolate the first voltage V _ BUS and the third voltage BUS +, the power isolation circuit 300 includes a first isolation circuit 301, a second isolation circuit 302 and a first voltage regulator D17, two ends of the first isolation circuit 301 are electrically connected to a first power supply port (corresponding to the first voltage V _ BUS) and a second power supply port (corresponding to the third voltage BUS +), two ends of the second isolation circuit 302 are electrically connected to a first power GND2 and a second power BUS- (negative power source end of the BUS power) respectively, and the second power supply port is further electrically connected to a second power supply BUS-through a first voltage regulator D7; the first isolation circuit 301 includes a first current-limiting resistor R17, a first switch Q1, a first resistor (in this embodiment, the first resistor is composed of a resistor R18 and a resistor R21 connected in series), and a second voltage regulator D4, the first switch Q1 includes a first control end, a first input end, and a first output end, one end of the first current-limiting resistor R17 is connected to a first power supply port (corresponding to a first voltage V _ BUS), one end of the first resistor, and an anode of the second voltage regulator D4, the other end of the first current-limiting resistor R17 is connected to the first control end, the first input end is connected to a cathode of the second voltage regulator D4, and the first output end is connected to the other end of the first resistor and a second power supply port (corresponding to a third voltage BUS +); the second isolation circuit 302 includes a second current-limiting resistor R27, a second switch Q2, a second resistor (in this embodiment, the second resistor is composed of a resistor R26 and a resistor R22 connected in series), and a third regulator D9, the second switch Q2 includes a second control end, a second input end, and a second output end, one end of the second current-limiting resistor R27 is connected to the second power BUS-, the anode of the first regulator D7, the anode of the third regulator D9, and one end of the second resistor, the other end of the second current-limiting resistor R27 is connected to the second control end, the second input end is connected to the cathode of the third regulator D9, and the second output end is connected to the other end of the second resistor and the first power GND 2.

It should be noted that the first power supply GND2 and the second power supply BUS-respectively represent negative power supplies opposite to the first voltage V _ BUS and the third voltage BUS +, and meanwhile, the first isolation circuit 301 and the second isolation circuit 302 of the present embodiment respectively constitute a positive power supply isolation circuit and a negative power supply isolation circuit for isolating positive power supplies and negative voltages of the BUS power supply.

The first switch tube Q1 and the second switch tube Q2 in the embodiment of the present application include, but are not limited to, a triode or a MOS transistor. Moreover, according to the disclosure of the present application, a person skilled in the art can easily think of modifying the power isolation circuit 300 disclosed in the present application into a power isolation circuit 300 adapted to the selection of the switching tube according to the specific selection of the switching tube, and therefore, the present application can be implemented whether the switching tube is a triode of NPN type or PNP type, or a switching MOS tube of N-channel or P-channel, and is not limited in the embodiments of the present application. In the embodiment, the first switch tube Q1 and the second switch tube Q2 are preferably SS8550 triodes; meanwhile, the first, second and third regulators D7, D4 and D9 include, but are not limited to, a zener diode or a breakdown diode, and in the present embodiment, a 1N4148W zener diode is preferable. In this embodiment, the first zener tube D7 functions as: the third voltage exceeds a certain value due to some reason, the first voltage regulator tube D7 is broken down, so that the output of the power isolation circuit 300 is short-circuited, and the KNX bus power supply unit 200 stops outputting, thereby avoiding the damage of the overhigh output voltage to the electric equipment. In some embodiments, to further achieve isolation of the first voltage V _ BUS and the third voltage BUS +, the choke unit 400 includes a two-wire inductor L2, a first rectifier D2, a third switch Q3, a third resistor R37, and a fourth resistor R38, wherein the two-wire inductor L2 includes a fifth port (pin 9 of the two-wire inductor L2), a sixth port (pin 3 of the two-wire inductor L2), a seventh port (pin 2 of the two-wire inductor L2), an eighth port (pin 11 of the two-wire inductor L2), a ninth port (pin 8 of the two-wire inductor L2), and a tenth port (pin 7 of the two-wire inductor L2), the third switch Q3 includes a third control terminal, a third input terminal, and a third output terminal, the fifth port connects the first power supply port and the third port (the first port and the third port both connect the first voltage V _ BUS), the sixth port is connected with the second power supply port and the fourth port (the sixth port and the fourth port are both connected with a third voltage BUS +), the seventh port is connected with a second power supply BUS-, the eighth port is connected with a first power supply GND2, the ninth port is connected with the anode of the first rectifying tube D2 and one end of a third resistor R37, the cathode of the first rectifying tube D2 is connected with a third output end, the other end of the third resistor R37 is connected with a third control end, the third output end is connected with one end of a fourth resistor R38, and the other end of the fourth resistor R38 is connected with the tenth port.

It should be noted that, in this embodiment, the third switching tube Q3 includes, but is not limited to, a triode, and in this embodiment, the third switching tube Q3 is preferably a triode of MMBT2907A type, and the first rectifying tube D2 is preferably a rectifying diode of ES1D type.

The dual-wire inductor L2 of the present embodiment operates to generate a low impedance to differential mode signals through the built-in differential mode choke of the dual-wire inductor L3 when differential mode current is present, and to suppress common mode signals through the built-in common mode choke when common mode current is present.

Fig. 3 is a schematic circuit diagram of a switching power supply unit according to an embodiment of the present invention, as shown in fig. 3, in some embodiments, to convert the utility grid voltage into the first voltage V _ BUS and the second voltage V2, the switching power supply unit 100 includes:

a rectifier circuit 101 for rectifying an ac voltage (195V to 255V) input from the utility grid into a fourth voltage (the fourth voltage is a dc voltage);

an inverter T1, including a primary winding, a first secondary winding, a second secondary winding and an auxiliary winding, wherein the first secondary winding is connected to a first positive output terminal (corresponding to the first voltage V _ BUS) through a first output rectification circuit 102, and the second secondary winding is connected to a second positive output terminal (corresponding to the second voltage V2) of the switching power supply unit 100 through a second output rectification circuit 103;

the main control circuit 104 comprises a switching power supply chip U2, the switching power supply chip U2 comprises a fourth input end, a fourth control end and a first feedback end, the fourth input end is respectively connected with the rectifying circuit 101 and the auxiliary winding through the online voltage detection circuit 105 and the first power supply circuit 106, the fourth control end is connected with the primary winding, and the first feedback end is connected with the first secondary winding through the voltage negative feedback circuit 107;

the rectifier circuit 101 provides a power supply for starting the switching power supply chip U2, the auxiliary winding provides a working power supply for the switching power supply chip U2 after starting, the switching power supply chip U2 obtains a change signal reflecting the output voltage of the first output rectifier circuit 102 through the voltage negative feedback circuit 107, controls the inverter T1 to convert the fourth voltage into an inverted voltage, and rectifies the inverted voltage into a first voltage V _ BUS and a second voltage V2 through the first output rectifier circuit 102 and the second output rectifier circuit 103 respectively.

It should be noted that, when the switching power supply unit 100 works, the rectification circuit 101 rectifies the voltage of the utility grid into a fourth voltage, the fourth voltage is used as a starting voltage of the switching power supply chip U2, and simultaneously, the fourth voltage is also used as an input voltage of the primary winding, the inverter T1 converts the fourth voltage into a first inversion voltage and a second inversion voltage respectively according to the turn ratio of the primary winding to the first secondary winding and the turn ratio of the primary winding to the second secondary winding, and simultaneously, the inverter T1 also converts the fourth voltage into a power supply for the switching power supply chip U2 to work after starting according to the turn ratio of the primary winding to the auxiliary winding; when the switching power supply chip U2 works, the voltage negative feedback circuit 107 collects a signal reflecting the voltage change of the first output rectifying circuit 102 and feeds back the signal to the switching power supply chip U2, and the switching power supply chip U2 controls the on/off of the power switching tube therein according to the voltage change signal to correspondingly turn on or off the primary winding connected to the drain of the power switching tube therein, so that the inverter T1 converts the fourth voltage rectified by the rectifying circuit 101 into an inversion voltage (high-frequency square-wave pulse voltage) and outputs the inversion voltage along the first output rectifying circuit 102 and the second output rectifying circuit 103, thereby providing a first voltage V _ BUS and a second voltage V2 corresponding to the KNX BUS power supply unit 200 and the auxiliary power supply unit, respectively.

In this embodiment, the switching power chip U2 includes, but is not limited to, a TOP271E switching power chip.

In some embodiments, to rectify the utility grid voltage into a fourth voltage, the rectifier circuit 101 includes an electromagnetic filter circuit and an input rectifier circuit connected in sequence, an input end of the electromagnetic filter circuit is connected to the utility grid, an output end of the electromagnetic filter circuit is electrically connected to an input end of the input rectifier circuit, and an output end of the input rectifier circuit is connected to the primary winding (the end of the primary winding that is the same name as the primary winding), wherein the electromagnetic filter circuit is configured to filter the utility grid voltage into a first ac voltage, and the input rectifier circuit is configured to rectify the first ac voltage into the fourth voltage.

In this embodiment, the electromagnetic filter circuit includes a first voltage dependent resistor RV1, a first filter capacitor C7 and an EMI inductor L4, the first voltage dependent resistor RV1 and the first filter capacitor C7 are connected in parallel, an electrical connection point (including two electrical connection points) of the first voltage dependent resistor RV1 and the first filter capacitor C1 is connected to two input ends of a commercial power grid (a zero line and a live line) and an EMI inductor L4, and two output ends of the EMI inductor L4 are connected to input ends of the input rectifier circuit.

In the present embodiment, the first voltage dependent resistor RV1 includes but is not limited to a TVR1471 model subtense resistor, and the EMI inductor L4 includes but is not limited to an SQ1918-11mh inductor.

In this embodiment, the input rectifying circuit includes a rectifying bridge B1 and a first thermistor RT1, two input terminals of the rectifying bridge B1 are respectively connected to two output terminals of the EMI inductor L4, one of two output terminals of the rectifying bridge B1 is connected in series with the first thermistor RT1 and is connected to the same-name terminal of the primary winding, and the other of two output terminals of the rectifying bridge B1 is connected to a third power supply PGND.

It should be noted that, in the embodiment of the present application, the rectifier bridge B1 includes, but is not limited to, an integrated bridge stack type rectifier bridge, for example: KBJ608G, it may also be a rectifier bridge constructed with a plurality of rectifier diodes, such as: a rectifier bridge consisting of four 1N4007 diodes is selected; in this embodiment, the first thermistor RT1 is used to perform overload protection on the switching power supply unit 100, and when the output terminal (the first voltage V _ BUS and the second voltage V2) of the switching power supply unit 100 is overloaded for output, the fourth voltage output along the rectifier bridge B1, after flowing through the first thermistor RT1, increases the temperature of the first thermistor RT1, increases the resistance of the first thermistor RT1, decreases the current flowing to the primary winding of the inverter T1, and decreases the power converted by the inverter T1, thereby adjusting the output of the switching power supply unit 100.

In some embodiments, in order to provide power for the switching power chip U1 to start and operate, the online voltage detection circuit 105 includes a plurality of third current-limiting resistors connected in series (in the embodiments of the present application, the plurality of third current-limiting resistors includes a resistor R7, a resistor R13, and a resistor R16), one end of the plurality of current-limiting resistors connected in series (one end of the resistor R7) is connected to the same-name end of the primary winding, and the other end of the plurality of current-limiting resistors connected in series (one end of the resistor R16) is connected to a fourth input end (the end is the power input end of the switching power chip); when the switching power supply unit 100 operates, the fourth voltage rectified by the rectifying circuit 101 is input to the switching power supply chip U2 along the online voltage detection circuit 105, the switching power supply chip U2 is started based on the fourth voltage, and the plurality of third current limiting resistors are used for limiting the current input to the fourth input end of the switching power supply chip U2, so that the switching power supply chip U2 is prevented from being burnt. In this embodiment, the first power supply circuit includes a second rectifier tube D5 and a third rectifier tube (in this embodiment, the third rectifier tube includes two diodes D8 and D10 connected in series), a fourth regulator tube ZD1 and a fourth current-limiting resistor R25, the anode of the second rectifier tube D5 is connected to the different-name end of the auxiliary winding, the cathode of the second rectifier tube D5 is connected to the anode of the third rectifier tube (diode D8), the cathode of the third rectifier tube (diode D10) is connected to the anode of the fourth regulator tube ZD1, the cathode of the fourth regulator tube ZD1 is connected to the fourth current-limiting resistor R25, and the fourth current-limiting resistor R25 is further connected to the fourth input end. When the switching power supply unit 100 is in operation, the inverter T1 converts the fourth voltage into a corresponding auxiliary voltage according to the turn ratio between the primary winding and the auxiliary winding, the auxiliary voltage is rectified and stabilized by the second rectifier tube D5 and the third rectifier tube (in this embodiment, the third rectifier tube includes two diodes D8 and D10 connected in series), and the fourth regulator tube ZD1 forms a stable voltage for the switching power supply chip U2 to operate, and the fourth current limiting resistor R25 is used to limit the current input to the fourth input terminal of the switching power supply chip U2.

It should be noted that the second rectifying tube D5 includes, but is not limited to, an ES1D rectifying diode, the diode D8 and the diode D10 include, but is not limited to, a 1N4148 diode 4148W, and the fourth rectifying tube ZD1 includes, but is not limited to, an MMSZ5248 bidirectional rectifying tube.

In some embodiments, in order to rectify the inverted voltage into the first voltage V _ BUS and the second voltage V2, each of the first output rectification circuit 102 and the second output rectification circuit 103 includes a fourth rectification tube (in this embodiment, the fourth rectification tubes of the first output rectification circuit 102 and the second output rectification circuit 103 are respectively a diode D1 and a diode D2), an anode of the fourth rectification tube is connected to the different name end of the first secondary winding or the second secondary winding, a cathode of the fourth rectification tube passes through an LC-pi type filter circuit composed of a first filter inductor and two first filter capacitors (in this embodiment, the LC-pi type filter circuit of the first output rectification circuit 102 is composed of an inductor L1, a capacitor C4 and a capacitor C2, and the LC-pi type filter circuit of the second output rectification circuit 103 is composed of an inductor L2, a capacitor C9 and a capacitor C10) and the first positive output end (corresponding to the first voltage V _ BUS) or the second positive output end (corresponding to the second voltage V2) is connected to the first positive output end (corresponding to the second voltage V2) At least one second filter capacitor for eliminating ripples is further arranged between the LC-pi filter circuit and the first positive output end or the second positive output end (in this embodiment, the capacitor corresponding to the first output rectifying circuit 102 is a capacitor C3, and the capacitor corresponding to the second output rectifying circuit 103 is a capacitor C11 and a capacitor C20), and the fourth rectifying tube is further connected in parallel with an RC absorption network for absorbing spike pulses, which is composed of a fifth resistor and a third filter capacitor (in this embodiment, the RC absorption network of the first output rectifying circuit 102 is composed of a capacitor C1 and a resistor R1, and the RC absorption network of the second output rectifying circuit 103 is composed of a capacitor C5 and a resistor R8).

In this embodiment, the fourth rectifying tube includes, but is not limited to, a schottky diode of the MBR10200CT type.

In some embodiments, in order to collect the voltage variation of the first output rectifying circuit 102 and feed back the voltage variation to the switching power supply chip U2, the voltage negative feedback circuit 107 includes a controllable precise voltage regulator element U3, an optical coupler U1 and a peripheral resistor capacitor, the voltage reference electrode of the controllable precise voltage-stabilizing source element U3 is connected with the first positive output end (corresponding to the first voltage V _ BUS) by connecting in series the first sampling resistor R30, the light-emitting diode is connected with a first power supply GND2 through a first pull-down resistor R35 in series connection, the cathode of a light emitter of an optocoupler U1 is connected with the cathode of a controllable precise voltage-stabilizing source element U3, the anode of the light emitter is connected with the cathode of a fourth rectifier tube D1 of the first output rectifying circuit 102 through a sixth resistor R24 in series connection, a first isolation resistor R29 is connected between the cathode and the anode of the light emitter of the optocoupler U1 in series connection, and the collector of a light receiver of the optocoupler U1 is connected with a first coupling resistor R32 in series connection and is connected with a first feedback end; the voltage negative feedback circuit 107 samples the output voltage of the first output rectifying circuit 102 and feeds back the voltage change to the switching power supply chip U2, the switching power supply chip U2 converts the fourth voltage rectified by the rectifying circuit 101 into an inverted voltage according to the voltage change control inverter T1, and the inverted voltage is rectified into a first voltage V _ BUS and a second voltage V2 through the first output rectifying circuit 102 and the second output rectifying circuit 103 respectively.

It should be noted that, in this embodiment, the controllable precision voltage regulator element U3 includes but is not limited to a TL431 model controllable precision voltage regulator, and the optical coupler U1 includes but is not limited to a TLP185 optical coupler.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An isolated KNX power supply comprising: the utility model discloses a power supply unit, the utility grid is connected to switching power supply unit, KNX bus power supply unit and auxiliary power supply unit, the utility grid is connected to switching power supply unit's input electricity, switching power supply unit's output electricity is connected the KNX bus power supply unit with the auxiliary power supply unit, switching power supply unit is used for converting utility grid voltage into first voltage and second voltage, and supply power for KNX bus power supply unit and auxiliary power supply unit respectively, its characterized in that, the KNX bus power supply unit includes power isolation circuit and choke unit, power isolation circuit includes first power supply port and second power supply port, choke unit includes third port and fourth port, first power supply port respectively with the first positive output end of switching power supply unit with the third port electricity is connected, the second power supply port with the fourth port electricity is connected, the second power supply port still passes through at least one bus equipment of KNX bus electricity connection, wherein the content of the first and second substances,

the power isolation circuit is used for converting the first voltage into a third voltage for communication of the bus device and/or isolating the third voltage from the second voltage;

the choke unit is used for suppressing a common-mode interference signal of the power isolation circuit.

2. The isolated KNX power supply according to claim 1, wherein the power isolation circuit comprises a first isolation circuit, a second isolation circuit and a first voltage regulator tube, wherein two ends of the first isolation circuit are electrically connected with the first power supply port and the second power supply port respectively, two ends of the second isolation circuit are electrically connected with a first power supply and a second power supply respectively, and the second power supply port is further electrically connected with the second power supply through the first voltage regulator tube; wherein the content of the first and second substances,

the first isolation circuit comprises a first current-limiting resistor, a first switch tube, a first resistor and a second voltage-stabilizing tube, the first switch tube comprises a first control end, a first input end and a first output end, one end of the first current-limiting resistor is connected with the first power supply port, one end of the first resistor and the anode of the second voltage-stabilizing tube, the other end of the first current-limiting resistor is connected with the first control end, the first input end is connected with the cathode of the second voltage-stabilizing tube, and the first output end is connected with the other end of the first resistor and the second power supply port;

the second isolation circuit comprises a second current-limiting resistor, a second switch tube, a second resistor and a third voltage-stabilizing tube, the second switch tube comprises a second control end, a second input end and a second output end, one end of the second current-limiting resistor is connected with the second power supply, the anode of the first voltage-stabilizing tube, the anode of the third voltage-stabilizing tube and one end of the second resistor, the other end of the second current-limiting resistor is connected with the second control end, the second input end is connected with the cathode of the third voltage-stabilizing tube, and the second output end is connected with the other end of the second resistor and the first power supply.

3. The isolated KNX power supply according to claim 1, wherein the choke unit includes a two-wire inductor, a first rectifying tube, a third resistor, and a fourth resistor, wherein the two-wire inductor includes a fifth port, a sixth port, a seventh port, an eighth port, a ninth port, and a tenth port, the third rectifying tube includes a third control terminal, a third input terminal, and a third output terminal, the fifth port connects the first power supply port and the third port, the sixth port connects the second power supply port and the fourth port, the seventh port connects a second power supply, the eighth port connects a first power supply, the ninth port connects an anode of the first rectifying tube and one end of the third resistor, a cathode of the first rectifying tube connects the third output terminal, and the other end of the third resistor connects the third control terminal, the third output end is connected with one end of the fourth resistor, and the other end of the fourth resistor is connected with the tenth port.

4. The isolated KNX power supply according to claim 1, wherein the switching power supply unit includes:

the rectification circuit is used for rectifying alternating-current voltage input by the commercial power grid into fourth voltage;

the inverter comprises a primary winding, a first secondary winding, a second secondary winding and an auxiliary winding, wherein the first secondary winding is connected with the first positive output end through a first output rectifying circuit, and the second secondary winding is connected with the second positive output end of the switching power supply unit through a second output rectifying circuit;

the main control circuit comprises a switching power supply chip, the switching power supply chip comprises a fourth input end, a fourth control end and a first feedback end, the fourth input end is respectively connected with the rectifying circuit and the auxiliary winding through an online voltage detection circuit and a first power supply circuit, the fourth control end is connected with the primary winding, and the first feedback end is connected with the first secondary winding through a voltage negative feedback circuit;

the rectifier circuit provides a power supply for starting the switching power supply chip, the auxiliary winding provides a working power supply for starting the switching power supply chip, the switching power supply chip acquires a change signal reflecting the output voltage of the first output rectifier circuit through the voltage negative feedback circuit, the inverter is controlled to convert the fourth voltage into an inverted voltage, and the inverted voltage is rectified into the first voltage and the second voltage through the first output rectifier circuit and the second output rectifier circuit respectively.

5. The isolated KNX power supply of claim 4, wherein the switching power chip comprises a TOP271E switching power chip.

6. The isolated KNX power supply according to claim 4, wherein the rectifier circuit comprises an electromagnetic filter circuit and an input rectifier circuit connected in series, an input end of the electromagnetic filter circuit is connected to a utility grid, an output end of the electromagnetic filter circuit is electrically connected to an input end of the input rectifier circuit, and an output end of the input rectifier circuit is connected to the primary winding, wherein the electromagnetic filter circuit is configured to filter a utility grid voltage to a first alternating voltage, and the input rectifier circuit is configured to rectify the first alternating voltage to the fourth voltage.

7. The isolated KNX power supply according to claim 6, wherein the electromagnetic filter circuit includes a first voltage dependent resistor, a first filter capacitor and an EMI inductor, the first voltage dependent resistor and the first filter capacitor are connected in parallel, electrical connection points of the first voltage dependent resistor and the first filter capacitor are respectively connected with two input ends of a utility grid and the EMI inductor, and two output ends of the EMI inductor are connected with input ends of the input rectification circuit;

the input rectifying circuit comprises a rectifying bridge and a first thermistor, two input ends of the rectifying bridge are respectively connected with two output ends of the EMI inductor, one of the two output ends of the rectifying bridge is connected with the first thermistor in series and is connected with the same-name end of the primary winding, and the other of the two output ends of the rectifying bridge is connected with a third power supply.

8. The isolated KNX power supply according to claim 4, wherein the on-line voltage detection circuit includes a plurality of third current limiting resistors connected in series, one end of the plurality of current limiting resistors connected in series is connected to the dotted terminal of the primary winding, and the other end of the plurality of current limiting resistors connected in series is connected to the fourth input terminal;

9. The isolated KNX power supply according to claim 4, wherein the first output rectifying circuit and the second output rectifying circuit each include a fourth rectifying tube, an anode of the fourth rectifying tube is connected to a different name end of the first secondary winding or the second secondary winding, a cathode of the fourth rectifying tube is connected to the first positive output end or the second positive output end through an LC-pi type filter circuit composed of a first filter inductor and two first filter capacitors, at least one second filter capacitor for eliminating ripples is further provided between the LC-pi type filter circuit and the first positive output end or the second positive output end, and the fourth rectifying tube is further connected in parallel to an RC absorption network composed of a fifth resistor and a third filter capacitor for absorbing spike pulses.

10. The isolated KNX power supply according to claim 9, wherein the voltage negative feedback circuit includes a controllable precision voltage regulator element, an optocoupler and a peripheral resistor capacitor, a voltage reference electrode of the controllable precision voltage regulator element is connected to the first positive output terminal by connecting a first sampling resistor in series and is connected to a first power supply by connecting a first pull-down resistor in series, a cathode of a light emitter of the optocoupler is connected to a cathode of the controllable precision voltage regulator element, an anode of the light emitter is connected to a cathode of the fourth rectifier tube of the first output rectifier circuit by connecting a sixth resistor in series, a first isolation resistor is connected in series between the cathode and the anode of the light emitter of the optocoupler, and a collector of a light receiver of the optocoupler is connected to a first coupling resistor in series and is connected to the first feedback terminal; the voltage negative feedback circuit samples the output voltage of the first output rectifying circuit and feeds back voltage change to the switching power supply chip, and the switching power supply chip controls the inverter to convert the fourth voltage rectified by the rectifying circuit into the inversion voltage according to the voltage change.