CN211239718U

CN211239718U - Building entrance guard power control system

Info

Publication number: CN211239718U
Application number: CN201922303293.1U
Authority: CN
Inventors: 温承华
Original assignee: Dongguan Wahhing Electrical Appliance Co ltd
Current assignee: Dongguan Wahhing Electrical Appliance Co ltd
Priority date: 2019-12-19
Filing date: 2019-12-19
Publication date: 2020-08-11
Anticipated expiration: 2029-12-19

Abstract

The utility model discloses a building entrance guard power control system, it includes: the DC power supply comprises an AC input module, an EMI filtering module, an input rectifying and filtering module, a PWM conversion module, an output rectifying and filtering module, a low-pass filtering module and a DC output module which are sequentially connected, wherein a PWM feedback module and a PWM control module are further arranged between the input rectifying and filtering module and the PWM conversion module, the PWM control module comprises a PWM control chip, an output overvoltage protection unit electrically connected with the PWM control chip and an output overcurrent protection unit electrically connected with the PWM control chip, and the PWM control chip is electrically connected with the PWM feedback module. The utility model discloses a set up the low pass filter module before DC output module, carry out effectual isolation by the high frequency noise and the access control system of low pass filter module in with the power, make the user can obtain higher communication quality.

Description

Building entrance guard power control system

The technical field is as follows:

the utility model relates to a power control field refers in particular to a building entrance guard power control system.

Background art:

with the continuous improvement of the scientific and technical level, the social economy is rapidly developed, and more multi-storey buildings are provided. Building access control systems are also increasingly being spotlighted by more people as indispensable devices in multi-story buildings. At present, a building access control power supply control system adopts a mode that the DC output of a switching power supply is directly connected with an access control system, and the mode directly causes high-frequency noise of the switching power supply to directly enter the access control system to influence the work of the access control system.

In view of the above, the present inventors propose the following.

The utility model has the following contents:

an object of the utility model is to overcome the not enough of prior art, provide a building access control power control system.

In order to solve the technical problem, the utility model discloses a following technical scheme: this building entrance guard power control system includes: the DC power supply comprises an AC input module, an EMI filtering module, an input rectifying and filtering module, a PWM conversion module, an output rectifying and filtering module, a low-pass filtering module and a DC output module which are sequentially connected, wherein a PWM feedback module and a PWM control module are further arranged between the input rectifying and filtering module and the PWM conversion module, the PWM control module comprises a PWM control chip, an output overvoltage protection unit electrically connected with the PWM control chip and an output overcurrent protection unit electrically connected with the PWM control chip, and the PWM control chip is electrically connected with the PWM feedback module.

Further, in the above technical solution, the low-pass filtering module includes a low-frequency differential mode inductor L3, a capacitor C26 electrically connected to the low-frequency differential mode inductor L3, and a high-frequency impedance unit electrically connected to the capacitor C26, where the high-frequency impedance unit includes an electrolytic capacitor EC25, a resistor R25, a resistor R25A, a resistor R25B, a resistor R25C, and a resistor R25D connected in series; a diode D26 and a diode D27 are connected in parallel to the low-frequency differential mode inductor L3, a diode D29 is connected in parallel in a reverse direction to the diode D26, and a diode D28 is connected in parallel in a reverse direction to the diode D27; the low-frequency differential mode inductor L3 is also connected with a diode D30 and a diode D31 in parallel, the diode D30 is reversely connected with a diode D33 in parallel, and the diode D31 is reversely connected with a diode D32 in parallel.

Further, in the above technical solution, the output overvoltage protection unit includes a resistor R10 connected to an RI pin in the PWM control chip, a 4-5 winding of a transformer T1 in the PWM conversion module connected to the resistor R10, a capacitor C4 and an electrolytic capacitor EC2 connected to a VDD pin in the PWM control chip, a resistor R5 and a resistor R6, and a diode D2 connected to the resistor R6, the capacitor C4 and the electrolytic capacitor EC2 are grounded to the other end of the 4-5 winding, and the resistor R5 is connected to the input rectification filter module through the resistor R4.

Further, in the above technical solution, the output overcurrent protection unit includes a SENSE pin of the PWM control chip, a capacitor C6 and a resistor R8 electrically connected to the SENSE pin, and a resistor R11 connected to the resistor R8, the other ends of the resistor R11 and the capacitor C6 are grounded, and the SENSE pin, the capacitor C6, the resistor R8, and the resistor R11 jointly implement current detection.

Further, in the above technical solution, the PWM control chip cooperates with the output overcurrent protection unit and the output overvoltage protection unit to form an output short circuit protection module; the PWM control module further comprises a switch MOS unit connected with a GATE pin of the PWM control chip, the switch MOS unit comprises a resistor R7 and a diode D3 which are connected with the GATE pin in the PWM control chip, a resistor R7A connected with the diode D3, a switch MOS and a resistor R7B which are connected with the resistor R7A and the resistor R7, the other end of the resistor R7B is connected with the resistor R11, an S pin and a D pin in the switch MOS are respectively connected with the resistor R11 and the PWM conversion module, the S pin and the D pin of the switch MOS are further connected with a capacitor C3, and the PWM feedback module is connected with an FB pin of the PWM control chip.

Further, in the above technical solution, the PWM feedback module includes an optical coupler U2 connected to the output rectifying and filtering module, a voltage dividing unit connected to the optical coupler U2, and an operational amplifier U3 connected to the voltage dividing unit, a first pin of the optical coupler U2 is connected to the output rectifying and filtering module through a resistor R27, a second pin of the optical coupler U2 is connected to the voltage dividing unit and the operational amplifier U3, a third pin of the optical coupler U2 is grounded, and a fourth pin of the optical coupler U2 is connected to the FB pin of the PWM control chip.

Further, in the above technical solution, the DC output module includes a first output unit connected to the output rectifying and filtering module and a second output unit connected to the low-pass filtering module.

Further, in the above technical solution, the output rectifying and filtering module includes a diode D21 connected to the positive electrode of the PWM conversion module, a diode D21A connected in parallel to the diode D21, a capacitor C21 and a resistor R21A connected in parallel to the diode D21A, a resistor R21 connected in parallel to the resistor R21A, and an electrolytic capacitor EC21 and an electrolytic capacitor EC22 connected to the diode D21, an electrolytic capacitor EC22A and a capacitor C32, the electrolytic capacitor EC21, the electrolytic capacitor EC22, the electrolytic capacitor EC22A, and the capacitor C32 are all connected to the negative electrode of the PWM conversion module, and an inductor L21, a capacitor C33, a capacitor EC23, a resistor R23, and a capacitor C25 are further disposed between the output rectifying and the low pass filtering module.

Further, in the above technical solution, the PWM conversion module includes a transformer T1 connected between the input rectifying and filtering module and the output rectifying and filtering module, a capacitor C2 and resistors R3D and R3E and a diode D1 connected in parallel to the transformer T1, a resistor R3A and a resistor R3C connected in parallel to the capacitor C2, a resistor R3 connected in parallel to the resistor R3A, and a resistor R3B connected in parallel to the resistor R3C, one end of the transformer T1 is further connected to the PWM control module, the transformer T1 is further connected in series to a capacitor CY2 and a capacitor CY1, and the capacitor CY1 is further connected to the input rectifying and filtering module.

Further, in the foregoing technical solution, the EMI filter module includes a common mode inductor LF1 connected to the AC input module, a resistor R1A and a resistor R1C connected in parallel to the common mode inductor LF1, a resistor R1 connected in parallel to the resistor R1A, a resistor R1B connected in parallel to the resistor R1C, and a capacitor CX1 connected in parallel to the resistor R1 and the resistor R1B, the input rectification filter module includes a comparator BD1 connected to the common mode inductor LF1, a capacitor CX2 and an electrolytic capacitor EC1 connected in parallel to the comparator BD1, a capacitor C1 connected in parallel to the electrolytic capacitor EC1, and a capacitor C1A connected in parallel to the capacitor C1, and one end of the electrolytic capacitor EC1 is grounded.

After the technical scheme is adopted, compared with the prior art, the utility model has following beneficial effect: the utility model discloses a set up the low pass filter module before DC output module, carry out effectual isolation by the high frequency noise and the access control system of low pass filter module in with the power, make the user can obtain higher communication quality. Meanwhile, a PWM control chip with the model number of OB2362I is adopted, excellent control performance and comprehensive protection function are achieved, abnormal conditions such as overcurrent, overvoltage, overload and overtemperature are detected cycle by cycle through the PWM control chip, and the power supply is protected rapidly when the abnormality occurs, so that more serious consequences are avoided.

Description of the drawings:

fig. 1 is a circuit diagram 1 of the present invention;

fig. 2 is a circuit diagram 2 of the present invention;

fig. 3 is a circuit diagram 3 of the present invention;

fig. 4 is a schematic diagram of the present invention;

fig. 5 is a parameter chart of the middle low-pass filtering module according to the present invention.

Description of reference numerals:

1 AC input module 2 EMI filter module 3 input rectification filter module

4 PWM conversion module 5 output rectification filter module 6 low-pass filter module

7 DC output module 8 PWM feedback module 9 PWM control module

The specific implementation mode is as follows:

the present invention will be further described with reference to the following specific embodiments and accompanying drawings.

As shown in fig. 1 to 5, a power control system for building entrance guard includes: the intelligent power supply comprises an AC input module 1, an EMI filtering module 2, an input rectifying and filtering module 3, a PWM conversion module 4, an output rectifying and filtering module 5, a low-pass filtering module 6 and a DC output module 7 which are sequentially connected, wherein a PWM feedback module 8 and a PWM control module 9 are further arranged between the input rectifying and filtering module 3 and the PWM conversion module 4, the PWM control module 9 comprises a PWM control chip, an output overvoltage protection unit electrically connected with the PWM control chip and an output overcurrent protection unit electrically connected with the PWM control chip, and the PWM control chip is electrically connected with the PWM feedback module 8. The PWM control module 9 receives the signal of the PWM feedback module 8, adjusts important parameters such as PWM duty cycle and frequency, and drives the switch MOS, thereby changing the operating state of the PWM conversion module 4.

The low-pass filtering module 6 comprises a low-frequency differential mode inductor L3, a capacitor C26 electrically connected with the low-frequency differential mode inductor L3, and a high-frequency impedance unit electrically connected with the capacitor C26, wherein the high-frequency impedance unit comprises an electrolytic capacitor EC25, a resistor R25, a resistor R25A, a resistor R25B, a resistor R25C and a resistor R25D which are connected in series; a diode D26 and a diode D27 are connected in parallel to the low-frequency differential mode inductor L3, a diode D29 is connected in parallel in a reverse direction to the diode D26, and a diode D28 is connected in parallel in a reverse direction to the diode D27; the low-frequency differential mode inductor L3 is also connected with a diode D30 and a diode D31 in parallel, the diode D30 is reversely connected with a diode D33 in parallel, and the diode D31 is reversely connected with a diode D32 in parallel. The power output end high-frequency impedance unit is provided with 100 omega high-frequency impedance and is used for isolating high-frequency components in the switch power supply and the access control system and preventing the switch power supply and the access control system from interfering with each other. The low-pass filtering module 6 has a high-frequency impedance of 100 omega, effectively isolates the high-frequency noise generated by the power supply from the access control system, prevents the high-frequency noise of the power supply from interfering with the video signal and the audio signal in the access control system, improves the video quality and reduces the background noise during the call. By accurately designing parameters of the low-frequency differential mode inductor L3, the electrolytic capacitor EC25, the electrolytic capacitor EC24, the electrolytic capacitor EC24A, the electrolytic capacitor EC24B, the electrolytic capacitor EC24C and the electrolytic capacitor EC24D, and calculating frequency and impedance, smaller high-frequency impedance can be met.

The output overvoltage protection unit comprises a resistor R10 connected with an RI pin in the PWM control chip, a 4-5 winding of a transformer T1 in the PWM conversion module 4 connected with the resistor R10, a capacitor C4, an electrolytic capacitor EC2, a resistor R5, a resistor R6 and a diode D2, wherein the capacitor C3524, the electrolytic capacitor EC2 and the 4-5 winding are connected with the VDD pin in the PWM control chip, the other end of the capacitor C4, the other end of the resistor R6, the other end of the resistor R5 and the input rectification filter module 3 are connected with one another through the resistor R4. The voltage detection module is formed by a winding of the transformer 4-5, a resistor R10 and an RI pin in the PWM control chip, when the output voltage is detected to be higher than 35V, the PWM control chip judges that the output voltage of the product is overvoltage and controls the PWM control module 9 to stop outputting until the overvoltage condition is relieved.

The output overcurrent protection unit comprises a SENSE pin of the PWM control chip, a capacitor C6 and a resistor R8 which are electrically connected with the SENSE pin, and a resistor R11 which is connected with the resistor R8, the other ends of the resistor R11 and the capacitor C6 are grounded, and the SENSE pin, the capacitor C6, the resistor R8 and the resistor R11 jointly realize current detection. The resistor R11, the resistor R8, the capacitor C6 and a SENSE pin of the PWM control chip jointly form a current detection module of a power supply, secondary output current is fed back to a primary winding of the transformer T1 through the transformer T1 and flows through the switch MOS Q1 and the resistor R11, a current signal is converted into a voltage signal through the resistor R11, and the voltage signal is filtered through the resistor R8 and the capacitor C6 and then fed back to the SENSE pin of the PWM control chip. When the output current exceeds the overcurrent point, the power supply enters an overcurrent protection state until the overcurrent state is relieved. The model of the PWM control chip is OB2362I, and the PWM control chip is a high-performance power supply controller proposed by a famous IC brand-Onbao, has excellent control performance and comprehensive protection function, detects abnormal conditions such as overcurrent, overvoltage, overload, overtemperature and the like cycle by cycle, and rapidly protects a power supply when the abnormality occurs so as to avoid more serious consequences.

The PWM control chip is matched with the output overcurrent protection unit and the output overvoltage protection unit to form an output short-circuit protection module; PWM control module 9 still including with the switch MOS unit that the GATE pin of PWM control chip is connected, switch MOS unit including with resistance R7 and diode D3 that the GATE pin is connected in the PWM control chip, with resistance R7A that diode D3 is connected and with resistance R7A and the switch MOS and the resistance R7B that resistance R7 is connected, the resistance R7B other end with resistance R11 is connected, in the switch MOS S foot and D foot respectively with resistance R11 and PWM conversion module 4 are connected, the S foot and the D foot of switch MOS still are connected with electric capacity C3, PWM feedback module 8 with the FB pin of PWM control chip is connected. When the voltage detection module detects that output voltage is too low and the current detection module detects that output current is higher than the overcurrent protection point, PWM control module 9 judges that the positive and negative poles of product output are short-circuited, and the power enters hiccup mode and has no output, and when short-circuit fault is relieved, the output automatically recovers the output.

PWM feedback module 8 including with the opto-coupler U2 that output rectification filter module 5 is connected, with the voltage division unit that opto-coupler U2 is connected and with the operational amplifier U3 that voltage division unit is connected, opto-coupler U2's first pin through resistance R27 with output rectification filter module 5 is connected, opto-coupler U2's second pin with voltage division unit with operational amplifier U3 connects, opto-coupler U2's third pin ground connection, opto-coupler U2's fourth pin with the FB pin of PWM control chip is connected. The PWM feedback module 8 detects the voltage and current at the output end, compares the detected voltage and current with a reference voltage, controls the reference voltage of the operational amplifier U3 and the working state of the optocoupler U2, and feeds back the working state of the secondary side to the primary side PWM control module 9, thereby achieving the purpose of adjusting PWM.

The output rectifying and filtering module 5 includes a diode D21 connected with the positive electrode of the PWM conversion module 4, a diode D21A connected in parallel with the diode D21, a capacitor C21 and a resistor R21A connected in parallel with the diode D21A, a resistor R21 connected in parallel with the resistor R21A, an electrolytic capacitor EC21 and an electrolytic capacitor EC22 connected with the diode D21, an electrolytic capacitor EC22A and a capacitor C32, the electrolytic capacitor EC21, the electrolytic capacitor EC22, the electrolytic capacitor EC22A and the capacitor C32 are all connected with the negative electrode of the PWM conversion module 4, and an inductor L21, a capacitor C33, a capacitor EC23, a resistor R23 and a capacitor C25 are further disposed between the output rectifying and filtering module 5 and the low-pass filtering module 6. The diode D21 and the diode D21A adopt a Schottky diode with 20A/200V and low conduction voltage drop, filtering adopts a long-life and low-loss electrolytic capacitor, and the conversion efficiency of the power supply is greatly improved.

Inductor L21 one end with diode D21 is connected, the inductance L21 other end with the 6 anodal connections of low pass filter module, electric capacity C33 one end with inductance L21 is connected, the inductance L21 other end with PWM conversion module 4 negative pole is connected, resistance R23 one end with PWM conversion module 4 negative pole is connected, the resistance R23 other end with the 6 negative pole of low pass filter module is connected, electric capacity C25 connect in parallel on resistance R23.

The PWM conversion module 4 includes a transformer T1 connected between the input rectifying and filtering module 3 and the output rectifying and filtering module 5, a capacitor C2 and resistors R3D and R3E connected in parallel to the transformer T1, a diode D1, a resistor R3A and a resistor R3C connected in parallel to the capacitor C2, a resistor R3 connected in parallel to the resistor R3A, and a resistor R3B connected in parallel to the resistor R3C, one end of the transformer T1 is further connected to the PWM control module 9, the transformer T1 is further connected in series to a capacitor CY2 and a capacitor CY1, and the capacitor CY1 is further connected to the input rectifying and filtering module 3.

The EMI filter module 2 includes a common mode inductor LF1 connected to the AC input module 1, a resistor R1A and a resistor R1C connected in parallel to the common mode inductor LF1, a resistor R1 connected in parallel to the resistor R1A, a resistor R1B connected in parallel to the resistor R1C, and a capacitor CX1 connected in parallel to the resistor R1 and the resistor R1B, the input rectifying filter module 3 includes a comparator BD1 connected to the common mode inductor LF1, a capacitor CX2 and an electrolytic capacitor EC1 connected in parallel to the comparator BD1, a capacitor C1 connected in parallel to the electrolytic capacitor EC1, and a capacitor C1A connected in parallel to the capacitor C1, and one end of the electrolytic capacitor EC1 is grounded. The EMI filtering module 2 is used for filtering noise in a power grid and a power supply so as to ensure that EMC meets safety standards when the power supply works and convert alternating current into direct current.

The DC output module 7 includes a first output unit connected to the output rectifying and filtering module 5 and a second output unit connected to the low-pass filtering module 6. The first output unit comprises a diode D25 and a common mode inductor LF3 connected with the output rectifying and filtering module 5, a resistor R45 and a resistor R46 and a resistor R47 connected in parallel to the common mode inductor LF3, and a terminal CON3 connected with the common mode inductor LF3, and the second output unit comprises a common mode inductor LF2 connected with the low pass filtering module 6, an inductor L22 and an inductor L23 respectively connected with the other end of the common mode inductor LF2, a terminal 2 connected with the inductor L22 and the inductor L23, and a resistor R25 and a capacitor C27 connected in parallel to the terminal CON 2. Each terminal of the DC output module 7 is subjected to a current of 10A and is wired according to the polarity indicated on the PCB. The DC output module is externally connected with a building entrance guard control system.

The AC input module 1 comprises a terminal CON1, a fuse F1 and a gate-in tube TH1 connected to two ends of the terminal CON1, and a voltage dependent resistor MOV1 connected in parallel to the fuse F1 and the gate-in tube TH 1. The AC input module 1 is used for transmitting electric energy to a power supply, and simultaneously, when the power supply works abnormally, the fuse is timely disconnected, so that more serious consequences are avoided.

In summary, the power supply is composed of an AC input module, an EMI & filter rectification module, a PWM converter module, an output rectifier filter module, a feedback module, a low pass filter module, and a DC output, and all the modules work in coordination to jointly complete each function of the power supply.

After the technical scheme is adopted, compared with the prior art, the utility model has following beneficial effect: the utility model discloses a set up low pass filter module 6 before DC output module 7, carry out effectual isolation with the high frequency noise in the power and access control system by low pass filter module 6, make the user can obtain higher communication quality. Meanwhile, a PWM control chip with the model number of OB2362I is adopted, excellent control performance and comprehensive protection function are achieved, abnormal conditions such as overcurrent, overvoltage, overload and overtemperature are detected cycle by cycle through the PWM control chip, and the power supply is protected rapidly when the abnormality occurs, so that more serious consequences are avoided. Just the utility model discloses possess wide voltage output, steady voltage output, power and the function of the high frequency noise mutual isolation between the system, accord with the safety standard simultaneously: EN62368, meeting the relevant EMC standards.

Of course, the above description is only an exemplary embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent changes and modifications made by the constructions, features, and principles of the present invention in accordance with the claims of the present invention are intended to be included in the scope of the present invention.

Claims

1. The utility model provides a building entrance guard power control system which characterized in that includes: the power supply comprises an AC input module (1), an EMI filtering module (2), an input rectifying and filtering module (3), a PWM conversion module (4), an output rectifying and filtering module (5), a low-pass filtering module (6) and a DC output module (7) which are sequentially connected, wherein a PWM feedback module (8) and a PWM control module (9) are further arranged between the input rectifying and filtering module (3) and the PWM conversion module (4), the PWM control module (9) comprises a PWM control chip, an output overvoltage protection unit electrically connected with the PWM control chip and an output overcurrent protection unit electrically connected with the PWM control chip, and the PWM control chip is electrically connected with the PWM feedback module (8).

2. The building access control power supply control system of claim 1, characterized in that: the low-pass filtering module (6) comprises a low-frequency differential mode inductor L3, a capacitor C26 electrically connected with the low-frequency differential mode inductor L3 and a high-frequency impedance unit electrically connected with the capacitor C26, wherein the high-frequency impedance unit comprises an electrolytic capacitor EC25, a resistor R25, a resistor R25A, a resistor R25B, a resistor R25C and a resistor R25D which are connected in series; a diode D26 and a diode D27 are connected in parallel to the low-frequency differential mode inductor L3, a diode D29 is connected in parallel in a reverse direction to the diode D26, and a diode D28 is connected in parallel in a reverse direction to the diode D27; the low-frequency differential mode inductor L3 is also connected with a diode D30 and a diode D31 in parallel, the diode D30 is reversely connected with a diode D33 in parallel, and the diode D31 is reversely connected with a diode D32 in parallel.

3. The building access control power supply control system of claim 1, characterized in that: the output overvoltage protection unit comprises a resistor R10 connected with an RI pin in the PWM control chip, 4-5 windings of a transformer T1 in the PWM conversion module (4) connected with the resistor R10, a capacitor C4 and an electrolytic capacitor EC2 and a resistor R5 which are connected with a VDD pin in the PWM control chip, a resistor R6, and a diode D2 connected with the resistor R6, the other ends of the capacitor C4 and the electrolytic capacitor EC2 and the 4-5 windings are grounded, and the resistor R5 is connected with the input rectification filter module (3) through the resistor R4.

4. The building access control power supply control system of claim 1, characterized in that: the output overcurrent protection unit comprises a SENSE pin of the PWM control chip, a capacitor C6 and a resistor R8 which are electrically connected with the SENSE pin, and a resistor R11 which is connected with the resistor R8, the other ends of the resistor R11 and the capacitor C6 are grounded, and the SENSE pin, the capacitor C6, the resistor R8 and the resistor R11 jointly realize current detection.

5. The building access control power supply control system of claim 4, characterized in that: the PWM control chip is matched with the output overcurrent protection unit and the output overvoltage protection unit to form an output short-circuit protection module; the PWM control module (9) further comprises a switch MOS unit connected with a GATE pin of the PWM control chip, the switch MOS unit comprises a resistor R7 and a diode D3 which are connected with the GATE pin in the PWM control chip, a resistor R7A connected with the diode D3, a switch MOS and a resistor R7B which are connected with the resistor R7A and the resistor R7, the other end of the resistor R7B is connected with the resistor R11, an S pin and a D pin in the switch MOS are respectively connected with the resistor R11 and the PWM conversion module (4), the S pin and the D pin of the switch MOS are further connected with a capacitor C3, and the PWM feedback module (8) is connected with the FB pin of the PWM control chip.

6. The building access control power supply control system of claim 5, characterized in that: PWM feedback module (8) including with output rectifier filter module (5) the optical coupling U2 of connecting, with the voltage division unit that optical coupling U2 is connected and with operational amplifier U3 that the voltage division unit is connected, optical coupling U2's first pin through resistance R27 with output rectifier filter module (5) are connected, optical coupling U2's second pin with the voltage division unit with operational amplifier U3 is connected, optical coupling U2's third pin ground connection, optical coupling U2's fourth pin with the FB pin of PWM control chip is connected.

7. The building access control power supply control system of claim 2, characterized in that: the DC output module (7) comprises a first output unit connected with the output rectifying and filtering module (5) and a second output unit connected with the low-pass filtering module (6).

8. The building access control power supply control system of claim 1, characterized in that: the output rectifying and filtering module (5) comprises a diode D21 connected with the anode of the PWM conversion module (4), a diode D21A connected in parallel with the diode D21, a capacitor C21 and a resistor R21A connected in parallel with the diode D21A, a resistor R21 connected in parallel with the resistor R21A, an electrolytic capacitor EC21 and an electrolytic capacitor EC22 connected with the diode D21, an electrolytic capacitor EC22A and a capacitor C32, the electrolytic capacitor EC21, the electrolytic capacitor EC22, the electrolytic capacitor EC22A and the capacitor C32 are all connected with the cathode of the PWM conversion module (4), and an inductor L21, a capacitor C33, a capacitor EC23, a resistor R23 and a capacitor C25 are further arranged between the output rectifying and filtering module (5) and the low-pass filtering module (6).

9. The building access control power supply control system of claim 1, characterized in that: the PWM conversion module (4) comprises a transformer T1 connected between the input rectifying and filtering module (3) and the output rectifying and filtering module (5), a capacitor C2 and resistors R3D and R3E which are connected in parallel to the transformer T1, a diode D1, a resistor R3A and a resistor R3C which are connected in parallel to the capacitor C2, a resistor R3 which is connected in parallel to the resistor R3A, and a resistor R3B which is connected in parallel to the resistor R3C, wherein one end of the transformer T1 is also connected with the PWM control module (9), the transformer T1 is also connected in series with a capacitor CY2 and a capacitor CY1, and the capacitor CY1 is also connected with the input rectifying and filtering module (3).

10. The building access control power supply control system of claim 1, characterized in that: the EMI filtering module (2) comprises a common-mode inductor LF1 connected with the AC input module (1), a resistor R1A and a resistor R1C which are connected in parallel on the common-mode inductor LF1, a resistor R1 which is connected in parallel on the resistor R1A, a resistor R1B which is connected in parallel on the resistor R1C, and a capacitor CX1 which is connected in parallel on the resistor R1 and the resistor R1B, the input rectifying and filtering module (3) comprises a comparator BD1 which is connected with the common-mode inductor LF1, a capacitor CX2 and an electrolytic capacitor EC1 which are connected in parallel on the comparator BD1, a capacitor C1 which is connected in parallel on the electrolytic capacitor EC1, and a capacitor C1A which is connected in parallel on the capacitor C1, and one end of the electrolytic capacitor EC1 is grounded.