Power circuit for rail transit lighting system

Abstract

This utility model discloses a power supply circuit for a rail transit lighting system, wherein the anode of the anti-reverse diode D2 is connected to the DC power input terminal V. in The cathode is connected in series with fuse F1, then splits into two paths. The first path connects to the input pin VIN of the high-voltage linear regulator U1, and the second path is grounded through rectifier diode D1 and then connected in parallel with input filter capacitor C2. The input pin VIN of U1 is connected to the positive terminal of C2, the output pin OUT of U1 is grounded through the output filter capacitor C1, and the adjustment pin ADJ of U1 is grounded through resistor R6. The base of transistor Q2 is grounded through resistor R6, and the base is also connected to the output pin OUT of U1 through resistor R2. The collector is connected to the input pin VIN of U1, and the emitter of Q2 is directly connected to the power output terminal V. out Simultaneously, the adjustment pin ADJ of U1 is connected via resistor R4. Through the above method, the power supply circuit for the rail transit lighting system of this utility model adopts the TL783CKCSE3 high-voltage linear regulator, which supports wide voltage input and high voltage differential drop, effectively coping with fluctuations in the rail transit power grid and ensuring stable operation of the lighting system.

Description

Technical Field

[0001] This utility model relates to the field of power supply driving technology for rail transit lighting circuits, and in particular to a power supply circuit for rail transit lighting systems. Background Technology

[0002] The current power supply for lighting systems in rail transit vehicles has the following shortcomings:

[0003] Voltage adaptability issues: When the input voltage fluctuates significantly, the output voltage stability of traditional linear voltage regulator circuits decreases significantly, causing flickering or uneven brightness in lighting equipment;

[0004] High voltage protection defects: Existing circuits lack protection against lightning overvoltage or operational overvoltage, which can easily cause electrical components to break down and be damaged.

[0005] System reliability weakness: The power supply architecture is highly complex, and the failure rate increases exponentially with the number of components, resulting in reduced system reliability;

[0006] Insufficient space compatibility: Due to its large overall size, the limited space in the vehicle's equipment compartment makes it difficult to achieve standardized deployment, resulting in its unusability.

[0007] Therefore, current lighting systems urgently need a power supply solution to meet the stringent requirements of rail transit lighting systems for power supply reliability, environmental adaptability, and space utilization. Utility Model Content

[0008] The main technical problem solved by this utility model is to provide a power supply circuit for a rail transit lighting system, which is a high-voltage linear regulator circuit based on the TL783CKCSE3 chip. It is used to provide a stable and reliable DC power supply for the lighting equipment of rail transit vehicles, realize wide-range stable conversion, realize output current limiting protection, effectively suppress input ripple and output noise, and adapt to the complex electromagnetic environment of rail transit.

[0009] To solve the above-mentioned technical problems, the present invention provides a power supply circuit for a rail transit lighting system, comprising:

[0010] The input circuit includes: a reverse protection diode D2 and a fuse F1;

[0011] The input rectifier and filter unit includes: a rectifier diode D1 and an input filter capacitor C2;

[0012] The voltage regulation unit includes: a high-voltage linear regulator U1, resistors R1, R3, R5, R4, and R6;

[0013] The control feedback unit includes: transistor Q2 and resistor R2;

[0014] The output rectifier and filter unit includes: an output filter capacitor C1;

[0015] The anode of the anti-reverse diode D2 is connected to the DC power input terminal V. in ,

[0016] The cathode of the anti-reverse diode D2 is connected in series with the fuse F1 and then splits into two paths. The first path is connected to the input pin VIN of the high-voltage linear regulator U1, and the second path is grounded after passing through the rectifier diode D1 and connected in parallel with the input filter capacitor C2.

[0017] The input pin VIN of the high-voltage linear regulator U1 is connected to the positive terminal of C2, the output pin OUT of the high-voltage linear regulator U1 is grounded through the output filter capacitor C1, and the adjustment pin ADJ of the high-voltage linear regulator U1 is grounded through the resistor R6.

[0018] The base of transistor Q2 is grounded through resistor R6, and the base of transistor Q2 is also connected to the output pin OUT of high-voltage linear regulator U1 through resistor R2 to connect to the control signal.

[0019] The collector of transistor Q2 is connected to the input pin VIN of high-voltage linear regulator U1.

[0020] The emitter of transistor Q2 is directly connected to the power output terminal V. out At the same time, it is connected to the adjustment pin ADJ of the high-voltage linear regulator U1 via resistor R4.

[0021] In a preferred embodiment of this utility model, the DC power input terminal V in The input current is 110V.

[0022] In a preferred embodiment of this utility model, the anti-reverse diode D2 is used to prevent current flow when the power supply is reversed.

[0023] In a preferred embodiment of this invention, the fuse F1 is a resettable polymer fuse used to blow during overcurrent.

[0024] In a preferred embodiment of the present invention, the rectifier diode D1 is used to rectify the input DC voltage into a pulsating DC voltage.

[0025] In a preferred embodiment of this utility model, the formula for calculating the output voltage of the high-voltage linear regulator U1 is: V out =1.25V×(1+ R6 / R4 ).

[0026] The beneficial effects of this utility model are as follows: It adopts the TL783CKCSE3 high-voltage linear regulator, which supports wide voltage input and high voltage differential voltage drop, effectively copes with the fluctuation of the rail transit power grid, and ensures the stable operation of the lighting system; it uses the Q2 transistor and current sampling feedback to form an adaptive current limiting circuit, realizes dynamic current limiting protection under overload or short circuit, and improves system reliability; the dual capacitor filter structure effectively suppresses ripple and noise; the key components adopt industrial-grade standard packaging, with a compact structure, and are adapted to the complex electromagnetic environment of rail transit. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0028] Figure 1 This is a schematic diagram of a preferred embodiment of the power supply circuit for the rail transit lighting system of this utility model; Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0031] This utility model relates to a preferred embodiment of a power supply circuit for a rail transit lighting system.

[0032] Please see Figure 1 The power supply circuit for the rail transit lighting system includes: an input circuit, an input rectifier and filter unit, a voltage regulator unit, a control feedback unit, and an output rectifier and filter unit, wherein the input circuit, the input rectifier and filter unit, the voltage regulator unit, the control feedback unit, and the output rectifier and filter unit are cascaded in sequence.

[0033] In detail, firstly, there is the input circuit and the input rectifier and filter unit. The input circuit includes a reverse protection diode D2 and a fuse F1. The input rectifier and filter unit includes a rectifier diode D1 and an input filter capacitor C2. The anode of the reverse protection diode D2 is connected to the DC power input terminal V. in The DC power input terminal V in The input current is 110V.

[0034] The cathode of the anti-reverse diode D2 is connected in series with the fuse F1 and then splits into two paths. The first path is connected to the input pin VIN of the high-voltage linear regulator U1, and the second path is grounded after passing through the rectifier diode D1, and is connected in parallel with the input filter capacitor C2.

[0035] A 110V DC power supply is directly connected to the power circuit. The reverse protection diode D2 ensures that the current flows in one direction. Then, the current flows through the fuse F1 and the rectifier diode D1 in sequence to form a pulsating DC voltage, which provides a stable voltage source for the subsequent circuits.

[0036] The fuse F1 is a resettable polymer fuse. Fuse F1 melts when there is an overcurrent, thereby cutting off the input current and preventing the circuit from being damaged due to overload.

[0037] The anti-reverse diode D2 is used to prevent current flow when the power supply is reversed. It cuts off the input when the input is reversed, thus protecting the subsequent circuit.

[0038] Secondly, there are a voltage regulation unit, a control feedback unit, and an output rectification and filtering unit. The voltage regulation unit includes a high-voltage linear regulator U1, resistors R1, R3, R5, R4, and R6. The control feedback unit includes a transistor Q2 and a resistor R2. The output rectification and filtering unit includes an output filter capacitor C1.

[0039] The input pin VIN of the high-voltage linear regulator U1 is connected to the positive terminal of C2, the output pin OUT of the high-voltage linear regulator U1 is grounded through the output filter capacitor C1, and the adjustment pin ADJ of the high-voltage linear regulator U1 is grounded through the resistor R6.

[0040] The base of transistor Q2 is grounded through resistor R6, and the base of transistor Q2 is also connected to the output pin OUT of high-voltage linear regulator U1 through resistor R2 to connect to the control signal.

[0041] The collector of transistor Q2 is connected to the input pin VIN of the high-voltage linear regulator U1, and the emitter of transistor Q2 is directly connected to the power output terminal V. out At the same time, it is connected to the adjustment pin ADJ of the high-voltage linear regulator U1 via resistor R4.

[0042] The working process of the power supply circuit for the rail transit lighting system of this utility model is as follows:

[0043] Input loop section:

[0044] First, the 110V input power is supplied from the DC power input terminal V. in The circuit is connected via a reverse protection diode D2 to ensure that the current can only flow in one direction, preventing damage to the circuit when the power supply is reversed.

[0045] The current then flows through fuse F1, which will melt in case of overcurrent, thereby cutting off the input current and preventing the circuit from being damaged due to overload.

[0046] The current is then rectified and preliminarily filtered in two paths: the first path is connected to the input pin VIN of the high-voltage linear regulator U1, directly powering the high-voltage linear regulator U1; the second path is grounded after passing through the rectifier diode D1 and connected in parallel with the input filter capacitor C2, which can smooth the pulsating DC voltage and form a preliminarily stable DC voltage, providing a stable voltage source for subsequent circuits.

[0047] Voltage regulation section:

[0048] The input pin VIN of the high-voltage linear regulator U1 receives the filtered DC voltage. Through an internal feedback mechanism, the high-voltage linear regulator U1 monitors the voltage at the adjustment pin ADJ and automatically adjusts the output voltage based on the ratio of resistors R6 and R4. The output voltage is determined by the ratio of resistors R6 and R4, calculated using the formula: V out =1.25V×(1+ R6 / R4 );

[0049] The output pin OUT of the high-voltage linear regulator U1 provides a stable voltage, which is further filtered by the output filter capacitor C1.

[0050] Control feedback section:

[0051] When the output current exceeds 700mA, transistor Q2 is triggered to conduct. The collector of Q2 pulls down the voltage at the ADJ terminal of the adjustment pin of the high-voltage linear regulator U1, which reduces the output current of U1 and achieves current limiting protection.

[0052] The output voltage is fed back to the base of transistor Q2 through a voltage divider between resistors R2 and R6, and the adjustment pin ADJ of U1 is dynamically adjusted to maintain voltage stability.

[0053] Output filter protection section:

[0054] A capacitor C1 is connected in parallel at the output of the high-voltage linear regulator U1. Through charging and discharging, it absorbs voltage fluctuations, provides a smoother DC power supply, and reduces interference to subsequent circuits.

[0055] The current-limiting protection resistor R5 is connected in series at the output pin OUT of the high-voltage linear regulator U1 to limit the output current and prevent overcurrent.

[0056] The beneficial effects of the power supply circuit for the rail transit lighting system of this utility model are:

[0057] It can provide a power supply circuit with wide input voltage and high differential voltage drop. It adopts the TL783CKCSE3 high voltage linear regulator, supports a wide input voltage of DC24V to DC1500V, and can maintain stable output voltage under high differential voltage. It can effectively cope with the fluctuation and transient impact of the rail transit power grid, ensure that the lighting system is flicker-free and brightness fluctuation-free, and achieve stable conversion over a wide range.

[0058] An adaptive current limiting circuit is constructed by using a Q2 transistor and current sampling feedback. It automatically adjusts the output current during overload or short circuit, provides dynamic current limiting protection, avoids thermal damage to components, and improves system reliability.

[0059] The dual-capacitor filter structure effectively suppresses high-frequency input ripple and output noise.

[0060] Adopting industrial-grade standard packaging, the overall structure is compact and can be adapted to the installation requirements of the narrow equipment compartment of rail transit. It can adapt to the complex electromagnetic environment of rail vehicles such as vibration and humidity, and has been widely used in intelligent intercity EMUs.

[0061] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A power supply circuit for a rail transit lighting system, characterized in that, include: The input circuit includes: a reverse protection diode D2 and a fuse F1; The input rectifier and filter unit includes: a rectifier diode D1 and an input filter capacitor C2; The voltage regulation unit includes: a high-voltage linear regulator U1, resistors R1, R3, R5, R4, and R6; The control feedback unit includes: transistor Q2 and resistor R2; The output rectifier and filter unit includes: an output filter capacitor C1; An anode of the anti-reverse diode D2 is connected to a direct current power input terminal V in , The cathode of the anti-reverse diode D2 is connected in series with the fuse F1 and then splits into two paths. The first path is connected to the input pin VIN of the high-voltage linear regulator U1, and the second path is grounded after passing through the rectifier diode D1 and connected in parallel with the input filter capacitor C2. The input pin VIN of the high-voltage linear regulator U1 is connected to the positive terminal of C2, the output pin OUT of the high-voltage linear regulator U1 is grounded through the output filter capacitor C1, and the adjustment pin ADJ of the high-voltage linear regulator U1 is grounded through the resistor R6. The base of transistor Q2 is grounded through resistor R6, and the base of transistor Q2 is also connected to the output pin OUT of high-voltage linear regulator U1 through resistor R2 to connect to the control signal. The collector of transistor Q2 is connected to the input pin VIN of high-voltage linear regulator U1. The emitter of the transistor Q2 is directly connected to the power supply output V out At the same time, the adjusting pin ADJ of the high-voltage linear stabilizer U1 is connected through the resistor R4.

2. The power supply circuit for a rail transit lighting system according to claim 1, characterized by, The direct current power input terminal V in The input current is 110V.

3. The power supply circuit for rail transit lighting system according to claim 1, characterized in that, The anti-reverse diode D2 is used to prevent current flow when the power supply is reversed.

4. The power supply circuit for a rail transit lighting system according to claim 1, characterized by, The fuse F1 is a resettable polymer fuse used to blow in case of overcurrent.

5. The power supply circuit for rail transit lighting system according to claim 1, wherein The rectifier diode D1 is used to rectify the input DC voltage into a pulsating DC voltage.

6. The power supply circuit for rail transit lighting system according to claim 1, wherein The output voltage of the high-voltage linear regulator U1 is calculated by the formula: V out = 1.25V x (1 + R6 / R4).

Images