An ACAC power supply module for railway signal power supply panel

Abstract

The present invention discloses an ACAC power supply module for a railway signal power supply panel, including a PFC module, a DCDC module and an inverter module, wherein: the PFC module is used to receive a preset single-phase AC input voltage input by an external single-phase AC input power supply, and after a boost process, outputs a preset first DC voltage to the DCDC module; the DCDC module is connected to the PFC module, and is used to receive the preset first DC voltage output by the PFC module, and after high-frequency isolation conversion to a preset second DC voltage, outputs it to the inverter module; the inverter module is connected to the DCDC module, and is used to receive the preset second DC voltage output by the DCDC module, and then after an inversion process, outputs a preset single-phase AC output voltage to the outside. The present invention can meet a wide range of single-phase AC voltage input requirements, has strong applicability, can better meet the user's usage requirements, and enhance the user's product usage experience.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit design of railway signal power supply panels, and in particular to an ACAC (ACAC, i.e., alternating current to alternating current conversion) power supply module for railway signal power supply panels. Background Art

[0002] The railway signal power supply panel is a device used in the railway industry to supply power to station signal equipment. According to the railway industry standard TB / T 1528 of the People's Republic of China, the railway signal power supply system equipment series standard requirements, the power supply panel should ensure that the input voltage is within the range of single-phase AC176V to single-phase AC253V, and the frequency is within the range of 50Hz±0.5Hz to be able to supply power stably.

[0003] At present, the power supply module in the existing railway signal power supply panel needs to adopt an industrial frequency transformer (also called a low-frequency transformer) for isolated power supply.

[0004] However, the existing power frequency transformer has the following technical defects:

[0005] 1. It cannot meet the requirements of a wide range of single-phase AC voltage input. The output voltage and frequency change with the input voltage and frequency. It cannot output voltage and frequency stably, has poor applicability, and affects the user's experience of using the product.

[0006] 2. The power frequency transformer is heavy, which makes the entire railway signal screen system heavy;

[0007] 3. The power density of the power module using the industrial frequency transformer is low. Summary of the invention

[0008] The purpose of the present invention is to provide an ACAC power supply module for a railway signal power supply panel in view of the technical defects in the prior art.

[0009] To this end, the present invention provides an ACAC power supply module for a railway signal power supply panel, which includes a PFC module, a DCDC module and an inverter module, wherein:

[0010] The PFC module is used to receive a preset single-phase AC input voltage inputted from an external single-phase AC input power source, and after performing a voltage boost process, output a preset first DC voltage to the DCDC module;

[0011] A DCDC module is connected to the PFC module, and is used to receive a preset first DC voltage output by the PFC module, and after high-frequency isolation conversion into a preset second DC voltage, output it to the inverter module;

[0012] The inverter module is connected to the DCDC module and is used to receive the preset second DC voltage output by the DCDC module, and then output a preset single-phase AC output voltage after inversion processing.

[0013] Preferably, the PFC module specifically includes a live line L and a neutral line N;

[0014] One end of the live wire L and one end of the neutral wire N are respectively connected to two ends of an external single-phase AC input power supply; wherein one end of the live wire L serves as a first voltage input terminal Vin1 of the PFC module;

[0015] The other end of the live wire L is connected to the anode of the diode D11 and the cathode of the diode D12 respectively;

[0016] The other end of the neutral line N is connected to the anode of the diode D13 and the cathode of the diode D14 respectively;

[0017] The cathode of the diode D11 and the cathode of the diode D13 converge and intersect at the end point M;

[0018] The endpoint M is connected to one end of the inductor L1 and one end of the inductor L2 respectively;

[0019] The anode of the diode D12 and the anode of the diode D14 converge and intersect at the terminal N;

[0020] The terminal N is respectively connected to the source S of the field effect transistor S1, the source S of the field effect transistor S2, one end of the capacitor C1 and one end of the resistor R1;

[0021] Terminal N is also grounded;

[0022] The other end of the inductor L1 is connected to the drain D of the field effect transistor S1 and the anode of the diode D1 respectively;

[0023] The cathode of the diode D1 is connected to the other end of the capacitor C1 , the other end of the resistor R1 , and the first voltage output terminal Vout1 , respectively.

[0024] Preferably, both the field effect transistors S1 and S2 are NMOS field effect transistors.

[0025] Preferably, the DCDC module specifically comprises a second voltage input terminal Vin2;

[0026] A second voltage input terminal Vin2 connected to a first voltage output terminal Vout1 in the PFC module;

[0027] The second voltage input terminal Vin2 is respectively connected to one end of the capacitor C20, the drain D of the field effect transistor Q21, the drain D of the field effect transistor Q23 and the drain D of the field effect transistor Q25;

[0028] The other end of capacitor C20 is grounded;

[0029] The other end of the capacitor C20 is also connected to the source S of the field effect transistor Q22, the source S of the field effect transistor Q24 and the source S of the field effect transistor Q26 respectively;

[0030] Wherein, the source S of the field effect transistor Q21 and the drain D of the field effect transistor Q22 are both connected to one end of the inductor L21;

[0031] The other end of the inductor L21 is connected to one end of the capacitor C21;

[0032] The other end of capacitor C21 is connected to the A end of the primary coil in transformer T1;

[0033] Wherein, the source S of the field effect transistor Q23 and the drain D of the field effect transistor Q24 are both connected to one end of the inductor L22;

[0034] The other end of the inductor L22 is connected to one end of the capacitor C22;

[0035] The other end of capacitor C22 is connected to the A end of the primary coil in transformer T2;

[0036] Wherein, the source S of the field effect transistor Q25 and the drain D of the field effect transistor Q26 are both connected to one end of the inductor L23;

[0037] The other end of the inductor L23 is connected to one end of the capacitor C23;

[0038] The other end of capacitor C23 is connected to the A end of the primary coil in transformer T3;

[0039] Among them, the B end of the primary coil in the transformer T1, the B end of the primary coil in the transformer T2 and the B end of the primary coil in the transformer T3 intersect together;

[0040] Among them, the D end of the secondary coil in the transformer T1, the D end of the secondary coil in the transformer T2 and the D end of the secondary coil in the transformer T3 intersect together;

[0041] Wherein, the C end of the secondary coil in the transformer T1 is connected to the anode of the diode D25 and the cathode of the diode D26 respectively;

[0042] The C end of the secondary coil in the transformer T2 is connected to the anode of the diode D23 and the cathode of the diode D24 respectively;

[0043] The C terminal of the secondary coil in the transformer T3 is connected to the anode of the diode D21 and the cathode of the diode D22 respectively;

[0044] The cathode of the diode D21, the cathode of the diode D23 and the cathode of the diode D25 are respectively connected to the second voltage output terminal Vout2, one end of the capacitor C24 and one end of the resistor R20 after they converge and intersect.

[0045] The anode of the diode D22 , the anode of the diode D24 , the anode of the diode D26 , the other end of the capacitor C24 , and the other end of the resistor R20 are all grounded.

[0046] Preferably, the field effect transistors Q21 to Q26 are all NMOS field effect transistors.

[0047] Preferably, the inverter module specifically comprises a third voltage input terminal Vin3;

[0048] A third voltage input terminal Vin3 is connected to the second voltage output terminal Vout2 in the DCDC module;

[0049] The third voltage input terminal Vin3 is respectively connected to one end of the capacitor C30, the drain electrode D of the field effect transistor Q31 and the drain electrode D of the field effect transistor Q33;

[0050] The other end of capacitor C30 is grounded;

[0051] The other end of the capacitor C30 is also connected to the source S of the field effect transistor Q32 and the source S of the field effect transistor Q34 respectively;

[0052] Wherein, the source S of the field effect transistor Q31 and the drain D of the field effect transistor Q32 are both connected to one end of the inductor L31;

[0053] The source electrode S of the field effect transistor Q33 and the drain electrode D of the field effect transistor Q34 are both connected to one end of the inductor L32;

[0054] The other end of the inductor L31 is respectively connected to one end of the capacitor C31, one end of the resistor R30 and one end of the third voltage output terminal Vout3;

[0055] The other end of the inductor L32 is connected to the other end of the capacitor C31 and one end of the resistor R30 respectively;

[0056] The other end of the inductor L32 is connected to one end of the third voltage output terminal Vout3 .

[0057] Preferably, the field effect transistors Q31 to Q34 are all NMOS field effect transistors.

[0058] It can be seen from the technical solution provided by the present invention that, compared with the prior art, the present invention provides an inverter power supply module for a railway signal power supply panel, which is scientifically designed, can meet the requirements of a wide range of single-phase AC voltage input, has stable voltage and frequency output, has strong applicability, can better meet the user's usage needs, and enhance the user's product usage experience, and has great production practice significance.

[0059] In addition, the present invention adopts a high-frequency transformer, which is light in weight and is beneficial to reducing the weight of the entire railway signal screen system.

[0060] In addition, the present invention performs PFC control boosting, DCDC isolation and inversion on a single-phase AC power supply with a wide input range, and outputs a stable and adjustable AC output power supply, thereby ultimately improving the power density and various technical indicators of the AC power supply module. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 A schematic diagram of the overall structure of an ACAC power supply module for a railway signal power supply panel provided by the present invention;

[0062] Figure 2 A circuit schematic diagram of a PFC module in an ACAC power supply module for a railway signal power supply panel provided by the present invention;

[0063] Figure 3 A circuit schematic diagram of a DCDC module in an ACAC power supply module for a railway signal power supply panel provided by the present invention;

[0064] Figure 4 The present invention provides a circuit schematic diagram of an inverter module in an ACAC power supply module for a railway signal power supply panel. DETAILED DESCRIPTION

[0065] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0066] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0067] See also Figures 1 to 4The present invention provides an ACAC power supply module for a railway signal power supply panel, which adopts a high-frequency transformer isolation method to replace the traditional power frequency transformer isolation, and specifically includes a PFC module 100, a DCDC (DCDC is a DC to DC isolation conversion) module 200 and an inverter module 300, wherein:

[0068] The PFC module 100 is used to receive a preset single-phase AC input voltage (e.g., a 220V single-phase AC input voltage) input from an external single-phase AC input power source, and after performing a voltage boost process, output a preset first DC voltage (i.e., a bus voltage, e.g., a 400V DC voltage) to the DCDC module 200;

[0069] A DCDC (DCDC stands for direct current to direct current conversion) module 200 is connected to the PFC module 100, and is used to receive a preset first DC voltage output by the PFC module 100, and after high-frequency isolation conversion into a preset second DC voltage (e.g., a DC voltage of 400V), output it to the inverter module 300;

[0070] The inverter module 300 is connected to the DCDC module 200, and is used to receive the preset second DC voltage output by the DCDC module 200, and then output a preset single-phase AC output voltage to the outside after inversion processing (i.e., output to external electrical equipment, such as outputting a 220V single-phase AC voltage).

[0071] It should be noted that the preset single-phase AC input voltage input by the external single-phase AC input power supply can be a single-phase AC input voltage of rated 220V, or an AC input voltage varying in the range of AC176V to AC253V (e.g., a single-phase AC input voltage of rated 110V), or even an AC input power supply with a wider voltage range. The frequency of the input power supply is allowed to vary in the range of 45Hz to 65Hz, or even an AC input power supply in a wider frequency range.

[0072] In the present invention, it should be noted that the PFC module 100 may be as follows: Figure 2 The PFC functional unit composed of a two-phase staggered parallel BOOST structure shown may also be a PFC functional unit composed of a single BOOST structure or a multi-phase BOOST structure;

[0073] It should be noted that the DCDC module 200 can be as follows: Figure 3 The DCDC isolation conversion unit composed of the three-phase staggered parallel LLC topology shown may also be a DCDC isolation conversion unit composed of a single LLC topology or other multi-phase LLC topologies;

[0074] It should be noted that the inverter module 300 may be as follows: Figure 4The two-level inverter topology shown may also be a three-level or multi-level inverter topology.

[0075] It should be noted that the voltage values ​​marked in the present circuit structure are all one of the embodiments, and transformations of other voltage levels are applicable, such as a rated grid voltage of 110V, a DC200V intermediate bus voltage, etc.

[0076] It should be noted that the ACAC power supply module provided by the present invention is a high-frequency isolation module, which is divided into three stages in total: a front-stage PFC part, an intermediate DCDC isolation conversion, and a rear-stage single-phase inverter output part.

[0077] In the present invention, in a specific embodiment 1, the PFC module 100 has the following functions: the external 220V single-phase AC input voltage passes through the PFC circuit to achieve power factor correction, the power factor reaches 0.99, and the 400Vdc bus voltage is boosted and output, thereby supplying power to the DCDC isolation converter (i.e., the DCDC module 200);

[0078] In the present invention, in a specific embodiment 1, the DCDC module 200 has the following functions: mainly plays the role of high-frequency isolation, converting the 400Vdc output by the PFC module 100 into an isolated 400Vdc at high frequency, and supplying power to the subsequent inverter module 300. In addition, the primary-secondary isolation voltage of the DCDC isolation converter (i.e., the DCDC module 200) can reach more than 2000Vac.

[0079] In the present invention, in a specific embodiment 1, the inverter module 300 is used to: output a single-phase voltage of rated 220Vac after the 400Vdc outputted by the DCDC module 200 is subjected to full-bridge inversion processing. It should be noted that the frequency and output voltage value of the preset single-phase AC output power outputted by the inverter module 300 are adjustable, for example, they can be adjusted to 110Vac, and the frequency can be adjusted to different frequencies such as 25Hz, 50Hz, 75Hz or 175Hz.

[0080] In the present invention, the specific implementation is as follows: Figure 2 , the PFC module 100 specifically includes a live line L and a neutral line N;

[0081] One end of the live wire L and one end of the neutral wire N are respectively connected to two ends of an external single-phase AC input power supply (for example, a 220V single-phase AC input power supply);

[0082] One end of the live wire L serves as a first voltage input terminal Vin1 of the PFC module 100;

[0083] The other end of the live wire L is connected to the anode of the diode D11 and the cathode of the diode D12 respectively;

[0084] The other end of the neutral line N is connected to the anode of the diode D13 and the cathode of the diode D14 respectively;

[0085] The cathode of the diode D11 and the cathode of the diode D13 converge and intersect at the end point M;

[0086] The endpoint M is connected to one end of the inductor L1 and one end of the inductor L2 respectively;

[0087] The anode of the diode D12 and the anode of the diode D14 converge and intersect at the terminal N;

[0088] The terminal N is respectively connected to the source S of the field effect transistor S1, the source S of the field effect transistor S2, one end of the capacitor C1 and one end of the resistor R1;

[0089] Terminal N is also grounded (i.e. connected to GND);

[0090] The other end of the inductor L1 is connected to the drain D of the field effect transistor S1 and the anode of the diode D1 respectively;

[0091] The cathode of the diode D1 is connected to the other end of the capacitor C1 , the other end of the resistor R1 , and the first voltage output terminal Vout1 , respectively.

[0092] It should be noted that the first voltage output terminal Vout1 in the PFC module 100 is used to output a preset first DC voltage (ie, a bus voltage, such as a DC voltage of 400V) to the DCDC module 200;

[0093] The other end of the inductor L2 is connected to the drain D of the field effect transistor S2 and the anode of the diode D2 respectively;

[0094] In the present invention, it should be noted that the gate G of the field effect tube S1 and the gate G of the field effect tube S2 are used to receive the PWM (pulse width modulation) drive signal output by the PFC (power factor correction) unit in the existing power module. The drive signal can be output by a microcontroller such as a single chip microcomputer in the existing power module (i.e., as a PFC control unit), and after isolation and amplification by the driver chip, the field effect tubes S1 and S2 are driven to drive the conduction and shutdown of the field effect tubes S1 and S2. It can also be an existing, dedicated staggered parallel control integrated circuit to realize the output control of the drive, such as NCP1631 of ON Semiconductor, UCC28060 series integrated circuit of TI, and similar integrated circuits of other companies.

[0095] In a specific implementation, the field effect transistors S1 and S2 are both insulated gate field effect transistors (MOS transistors), specifically NMOS field effect transistors.

[0096] In order to more clearly understand the technical solution of the present invention, the working principle of the PFC module 100 is described below.

[0097] The main power topology circuit of the PFC module 100 is as follows Figure 2 As shown, an uncontrolled rectifier bridge is used to rectify the AC input voltage. The rectified voltage is boosted to 400Vdc through two parallel boost circuits staggered 180°. Due to the use of staggered parallel boost circuits, it has the following characteristics:

[0098] 1. Using average current control, the PFC inductor works in the continuous inductor state, and the inductor current ripple is small;

[0099] 2. Use voltage loop and current loop for power factor correction. The voltage loop obtains the corresponding duty cycle output V1 according to the target voltage and the actual voltage. The product of this value and the input voltage feedforward Vc is used as the current given by the two boost circuits to ensure that the input current tracks the input voltage, thereby achieving power factor correction.

[0100] 3. Using two boost circuits in parallel can effectively reduce the size of the PFC inductor, which is calculated as a reduction of half. In addition, using two-way interleaving can reduce input current harmonics, evenly distribute heat sources, and facilitate heat dissipation design;

[0101] 4. Two boost circuits are connected in parallel to achieve redundancy. That is, if one of the circuits is abnormal, the other circuit can output normally, but the power needs to be halved.

[0102] In the present invention, the specific implementation is as follows: Figure 3 , the DCDC module 200 specifically includes a second voltage input terminal Vin2;

[0103] It should be noted that the second voltage input terminal Vin2 is used to receive a preset first DC voltage (ie, a bus voltage, such as a DC voltage of 400 V) output by the first voltage output terminal Vout1 in the PFC module 100 .

[0104] A second voltage input terminal Vin2 is connected to the first voltage output terminal Vout1 in the PFC module 100;

[0105] The second voltage input terminal Vin2 is respectively connected to one end of the capacitor C20, the drain D of the field effect transistor Q21, the drain D of the field effect transistor Q23 and the drain D of the field effect transistor Q25;

[0106] The other end of capacitor C20 is grounded (i.e. connected to GND2);

[0107] The other end of the capacitor C20 is also connected to the source S of the field effect transistor Q22, the source S of the field effect transistor Q24 and the source S of the field effect transistor Q26 respectively;

[0108] Wherein, the source S of the field effect transistor Q21 and the drain D of the field effect transistor Q22 are both connected to one end of the inductor L21;

[0109] The other end of the inductor L21 is connected to one end of the capacitor C21;

[0110] The other end of capacitor C21 is connected to the A end of the primary coil in transformer T1;

[0111] Wherein, the source S of the field effect transistor Q23 and the drain D of the field effect transistor Q24 are both connected to one end of the inductor L22;

[0112] The other end of the inductor L22 is connected to one end of the capacitor C22;

[0113] The other end of capacitor C22 is connected to the A end of the primary coil in transformer T2;

[0114] Wherein, the source S of the field effect transistor Q25 and the drain D of the field effect transistor Q26 are both connected to one end of the inductor L23;

[0115] The other end of the inductor L23 is connected to one end of the capacitor C23;

[0116] The other end of capacitor C23 is connected to the A end of the primary coil in transformer T3;

[0117] Among them, the B end of the primary coil in the transformer T1, the B end of the primary coil in the transformer T2 and the B end of the primary coil in the transformer T3 intersect together;

[0118] Among them, the D end of the secondary coil in the transformer T1, the D end of the secondary coil in the transformer T2 and the D end of the secondary coil in the transformer T3 intersect together;

[0119] Wherein, the C end of the secondary coil in the transformer T1 is connected to the anode of the diode D25 and the cathode of the diode D26 respectively;

[0120] The C end of the secondary coil in the transformer T2 is connected to the anode of the diode D23 and the cathode of the diode D24 respectively;

[0121] The C terminal of the secondary coil in the transformer T3 is connected to the anode of the diode D21 and the cathode of the diode D22 respectively;

[0122] The cathode of the diode D21, the cathode of the diode D23 and the cathode of the diode D25 are respectively connected to the second voltage output terminal Vout2, one end of the capacitor C24 and one end of the resistor R20 after they converge and intersect.

[0123] The anode of the diode D22 , the anode of the diode D24 , the anode of the diode D26 , the other end of the capacitor C24 , and the other end of the resistor R20 are all grounded (ie, connected to GND2 ).

[0124] It should be noted that the second voltage output terminal Vout2 in the DCDC module 200 is used to output a preset second DC voltage to the inverter module 300 .

[0125] In the present invention, it should be noted that the gate G of the field effect transistors Q21 to Q26 is used to receive the PWM (pulse width modulation) drive signal output by the DC / DC control unit in the existing power module. The drive signal can be output by a microcontroller such as a single chip microcomputer in the existing power module (i.e., as a DC / DC control unit), and after isolation and amplification by the driver chip, it drives the field effect transistors Q21 to Q26.

[0126] In the present invention, transformers T1~T3 are high-frequency transformers (for example, transformers with an operating frequency exceeding the intermediate frequency 10kHz). High-frequency transformers T1~T3 can adopt existing well-known and common high-frequency transformers in switching power supplies. The three transformers form a Y / Y connection structure, which mainly plays a high-frequency isolation role in the present invention.

[0127] In a specific implementation, the field effect transistors Q21 to Q26 are all insulated gate field effect transistors (MOS transistors), specifically NMOS field effect transistors.

[0128] In order to more clearly understand the technical solution of the present invention, the working principle of the DCDC module 200 is described below.

[0129] In the present invention, the DCDC module 200 mainly plays an isolation role, inputting 400Vdc and outputting 400Vdc after isolation. Therefore, under the premise of satisfying isolation, it is necessary to ensure that the efficiency of the DCDC converter (i.e., the DCDC module 200) is the highest. Figure 3 The three-phase LLC (resonant circuit) shown

[0130] Staggered parallel connection. It has the following characteristics:

[0131] 1. By designing the operating frequency at the resonant frequency, the LLC topology can achieve ZVS of the primary MOS tube and ZCS of the secondary rectifier diode, achieving the highest efficiency of the topology;

[0132] 2. The three-phase LLC (resonant circuit) is staggered 120°, which can effectively reduce the size of the input and output filter capacitors. However, due to the retention time limit of the signal power supply, this advantage cannot be brought into play;

[0133] 3. Since there is no output filter inductor, the cost and weight of the DCDC converter (i.e., the DCDC module 200) are lower;

[0134] 4. Due to the high efficiency of soft switching, the switching frequency can be increased, further reducing the size and weight of the module.

[0135] In the present invention, the specific implementation is as follows: Figure 4 , the inverter module 300 specifically includes a third voltage input terminal Vin3;

[0136] It should be noted that the third voltage input terminal Vin3 is used to receive the preset second DC voltage (ie, bus voltage, such as a DC voltage of 400V) output by the second voltage output terminal Vout2 in the DCDC module 200 .

[0137] A third voltage input terminal Vin3 is connected to the second voltage output terminal Vout2 in the DCDC module 200;

[0138] The third voltage input terminal Vin3 is respectively connected to one end of the capacitor C30, the drain electrode D of the field effect transistor Q31 and the drain electrode D of the field effect transistor Q33;

[0139] The other end of capacitor C30 is grounded (i.e. connected to GND2);

[0140] The other end of the capacitor C30 is also connected to the source S of the field effect transistor Q32 and the source S of the field effect transistor Q34 respectively;

[0141] Wherein, the source S of the field effect transistor Q31 and the drain D of the field effect transistor Q32 are both connected to one end of the inductor L31;

[0142] The source electrode S of the field effect transistor Q33 and the drain electrode D of the field effect transistor Q34 are both connected to one end of the inductor L32;

[0143] The other end of the inductor L31 is respectively connected to one end of the capacitor C31, one end of the resistor R30 and one end of the third voltage output terminal Vout3 (ie, the AC-L end);

[0144] It should be noted that the third voltage output terminal Vout3 in the inverter module 300 outputs a preset single-phase AC output voltage to the outside (ie, outputs to an external electrical device).

[0145] The other end of the inductor L32 is connected to the other end of the capacitor C31 and one end of the resistor R30 respectively;

[0146] The other end of the inductor L32 is connected to the other end of the third voltage output terminal Vout3 (ie, the AC-N end).

[0147] In the present invention, it should be noted that the gate G of the field effect tubes Q31 to Q34 is used to receive the PWM (pulse width modulation) drive signal output by the inverter control unit in the existing power module. The drive signal can be output by a microcontroller such as a single-chip microcomputer in the existing power module (i.e., as an inverter control unit), and after isolation and amplification by a driver chip, it drives the field effect tubes Q31 to Q34, or it can be a dedicated inverter control integrated circuit to realize the output control of the drive, such as SG3525 of ON Semiconductor, EG8010 series integrated circuits of Yijing Microelectronics, and similar integrated circuits of other companies. Specifically, a microcontroller such as a single-chip microcomputer (i.e., as an inverter control unit) outputs 4 PWM drive signals, which are isolated and amplified by a driver chip, and then connected to the gate G poles of the field effect tubes Q31 to Q34 respectively, driving Q31 to Q34 to turn on and off.

[0148] In the present invention, in a specific implementation, the third voltage output terminal Vout3 can be used to output voltage to various AC signal equipment in the station to provide working power for these AC signal equipment, such as signal lighting equipment, switch indication equipment, etc., and can provide these signal equipment with a stable and reliable AC power supply with a specific voltage and frequency.

[0149] In a specific implementation, the field effect transistors Q31 to Q34 are all insulated gate field effect transistors (MOS transistors), specifically NMOS field effect transistors.

[0150] In order to more clearly understand the technical solution of the present invention, the working principle of the inverter module 300 is described below.

[0151] In the present invention, the topology circuit of the inverter module 300 is as follows: Figure 4 As shown, the inverter module 300 can output 220Vac or 110Vac by passing the input 400Vdc through the inverter bridge. The inverter topology has the following characteristics:

[0152] 1. Ordinary unipolar modulation control mode is adopted, Q31 and Q32 are used as high-frequency bridge arms, Q33 and Q34 are industrial frequency bridge arms. In the positive half cycle, Q31 is turned on at high frequency, Q32 is turned off, Q34 is normally open, and Q33 is turned off; in the negative half cycle, Q32 is turned on at high frequency, Q31 is turned off, Q33 is normally open, and Q34 is turned off;

[0153] 2. The inverter bridge has only one high-frequency tube at any time, so the switching loss is small and the efficiency is high;

[0154] 3. Since only one of Q31 and Q32 works in high-frequency mode, the possibility of bridge arm direct conduction in the high-frequency bridge arm is further reduced, and the inverter circuit has high reliability.

[0155] Therefore, based on the above technical solution design, for the present invention, through the mutual cooperation of the PFC module 100, the DCDC (DCDC is DC to DC conversion) module 200 and the inverter module 300, a wide range of AC voltage input can be achieved, and the parameters such as the AC power supply output voltage and frequency can be adjusted. The present invention is a new type of high-frequency isolated power supply that can reliably replace the traditional low-frequency transformer.

[0156] It should be noted that the present invention adopts a new high-frequency transformer and adopts cutting-edge power electronics technology during isolated power supply. It performs PFC control boost, DCDC isolation and inversion on a single-phase AC power supply with a wide input range, and outputs a stable and adjustable AC output power supply with intelligent, lightweight and easy-to-expand functions.

[0157] The inverter power supply module provided by the present invention eliminates the industrial frequency transformer and realizes the high frequency of the traditional inverter power supply through PFC boost, DCDC high frequency isolation and inverter output, thereby improving the power density of the AC power supply module.

[0158] In order to more clearly understand the technical solution of the present invention, the application scenario of the present invention is explained below in conjunction with specific application embodiments.

[0159] In one embodiment, at present, the voltage output by the AC power supply module of the railway signal power supply panel specifically includes two power supply forms, namely single-phase voltage 110Vac / 220Vac, frequency 25Hz, and single-phase voltage 220Vac, frequency 50Hz; wherein, the 25Hz AC power supply is a phase-sensitive track circuit power supply, which is divided into two types: track and local. The track power supply is 220Vac, 25Hz, and the local power supply is 110Vac, 25Hz. The phase angle of the local power supply ahead of the track power supply should be 90°±5°. In addition, the phases of the track power supply beams in the signal panel are consistent, and the phases of the local power supply beams are consistent. The 220Vac, 50Hz AC power supply is used to power loads such as microcomputer interlocking, signal lighting, and turnout indication. As the load's power requirements for the power supply increase, in order to facilitate the expansion of power, the AC power supply module needs to be connected in parallel in the power supply panel to achieve capacity expansion, and the control current sharing accuracy is within ±5%. After inspection, the AC power supply module provided by the present invention can fully meet the above requirements.

[0160] Compared with the prior art, the AC power supply module for railway signal power supply panel provided by the present invention has the following beneficial effects:

[0161] 1. Use advanced PFC (Power Factor Correction) control technology to accurately control the current phase and achieve high power factor;

[0162] 2. Adopt LLC (resonant circuit) high frequency isolation to replace the traditional low frequency transformer;

[0163] 3. Adopting full digital inverter control, the output parameters are flexible and adjustable;

[0164] 4. Provide RS485 communication interface to realize comprehensive status monitoring and online parameter modification, etc.

[0165] To sum up, compared with the prior art, the inverter power supply module for a railway signal power supply panel provided by the present invention has a scientific design, can meet the requirements of a wide range of single-phase AC voltage input, and can achieve voltage and frequency stability at the output. It has strong applicability, can better meet the user's usage needs, and enhance the user's product usage experience, and has great production practice significance.

[0166] In addition, the present invention adopts a high-frequency transformer, which is light in weight and is beneficial to reducing the weight of the entire railway signal screen system.

[0167] In addition, the present invention performs PFC control boosting, DCDC isolation and inversion on a single-phase AC power supply with a wide input range, and outputs a stable and adjustable AC output power supply, thereby ultimately improving the power density and various technical indicators of the AC power supply module.

[0168] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An ACAC power supply module for railway signal power supply panel, characterized in that: It comprises a PFC module (100), a DCDC module (200) and an inverter module (300), wherein: The PFC module (100) is used to receive a preset single-phase AC input voltage input from an external single-phase AC input power source, and after performing a voltage boost process, output a preset first DC voltage to the DCDC module (200); A DCDC module (200) is connected to the PFC module (100) and is used to receive a preset first DC voltage output by the PFC module (100), and after high-frequency isolation conversion into a preset second DC voltage, output it to the inverter module (300); An inverter module (300) is connected to the DCDC module (200) and is used to receive a preset second DC voltage output by the DCDC module (200), and then output a preset single-phase AC output voltage after an inversion process; The PFC module (100) specifically comprises a live line L and a neutral line N; One end of the live wire L and one end of the neutral wire N are respectively connected to two ends of an external single-phase AC input power supply; wherein one end of the live wire L serves as a first voltage input terminal Vin1 of the PFC module (100); The other end of the live wire L is connected to the anode of the diode D11 and the cathode of the diode D12 respectively; The other end of the neutral line N is connected to the anode of the diode D13 and the cathode of the diode D14 respectively; The cathode of the diode D11 and the cathode of the diode D13 converge and intersect at the end point M; The endpoint M is connected to one end of the inductor L1 and one end of the inductor L2 respectively; The anode of the diode D12 and the anode of the diode D14 converge and intersect at the terminal N; The terminal N is respectively connected to the source S of the field effect transistor S1, the source S of the field effect transistor S2, one end of the capacitor C1 and one end of the resistor R1; Terminal N is also grounded; The other end of the inductor L1 is connected to the drain D of the field effect transistor S1 and the anode of the diode D1 respectively; The cathode of the diode D1 is connected to the other end of the capacitor C1, the other end of the resistor R1 and the first voltage output terminal Vout1 respectively; The other end of the inductor L2 is connected to the drain D of the field effect transistor S2 and the anode of the diode D2 respectively.

2. The ACAC power supply module for railway signal power supply panel according to claim 1, characterized in that: Field effect transistors S1 and S2 are both NMOS field effect transistors.

3. The ACAC power supply module for railway signal power supply panel according to claim 1, characterized in that: The DCDC module (200) specifically comprises a second voltage input terminal Vin2; A second voltage input terminal Vin2 connected to a first voltage output terminal Vout1 in the PFC module (100); The second voltage input terminal Vin2 is respectively connected to one end of the capacitor C20, the drain D of the field effect transistor Q21, the drain D of the field effect transistor Q23 and the drain D of the field effect transistor Q25; The other end of capacitor C20 is grounded; The other end of the capacitor C20 is also connected to the source S of the field effect transistor Q22, the source S of the field effect transistor Q24 and the source S of the field effect transistor Q26 respectively; Wherein, the source S of the field effect transistor Q21 and the drain D of the field effect transistor Q22 are both connected to one end of the inductor L21; The other end of the inductor L21 is connected to one end of the capacitor C21; The other end of capacitor C21 is connected to the A end of the primary coil in transformer T1; Wherein, the source S of the field effect transistor Q23 and the drain D of the field effect transistor Q24 are both connected to one end of the inductor L22; The other end of the inductor L22 is connected to one end of the capacitor C22; The other end of capacitor C22 is connected to the A end of the primary coil in transformer T2; Wherein, the source S of the field effect transistor Q25 and the drain D of the field effect transistor Q26 are both connected to one end of the inductor L23; The other end of the inductor L23 is connected to one end of the capacitor C23; The other end of capacitor C23 is connected to the A end of the primary coil in transformer T3; Among them, the B end of the primary coil in the transformer T1, the B end of the primary coil in the transformer T2 and the B end of the primary coil in the transformer T3 intersect together; Among them, the D end of the secondary coil in the transformer T1, the D end of the secondary coil in the transformer T2 and the D end of the secondary coil in the transformer T3 intersect together; Wherein, the C end of the secondary coil in the transformer T1 is connected to the anode of the diode D25 and the cathode of the diode D26 respectively; The C end of the secondary coil in the transformer T2 is connected to the anode of the diode D23 and the cathode of the diode D24 respectively; The C terminal of the secondary coil in the transformer T3 is connected to the anode of the diode D21 and the cathode of the diode D22 respectively; The cathode of the diode D21, the cathode of the diode D23 and the cathode of the diode D25 are respectively connected to the second voltage output terminal Vout2, one end of the capacitor C24 and one end of the resistor R20 after they converge and intersect. The anode of the diode D22 , the anode of the diode D24 , the anode of the diode D26 , the other end of the capacitor C24 , and the other end of the resistor R20 are all grounded.

4. The ACAC power supply module for railway signal power supply panel according to claim 3, characterized in that: Field effect transistors Q21 to Q26 are all NMOS field effect transistors.

5. The ACAC power supply module for railway signal power supply panel according to claim 3, characterized in that: The inverter module (300) specifically comprises a third voltage input terminal Vin3; A third voltage input terminal Vin3 connected to a second voltage output terminal Vout2 in the DCDC module (200); The third voltage input terminal Vin3 is respectively connected to one end of the capacitor C30, the drain electrode D of the field effect transistor Q31 and the drain electrode D of the field effect transistor Q33; The other end of capacitor C30 is grounded; The other end of the capacitor C30 is also connected to the source S of the field effect transistor Q32 and the source S of the field effect transistor Q34 respectively; Wherein, the source S of the field effect transistor Q31 and the drain D of the field effect transistor Q32 are both connected to one end of the inductor L31; The source electrode S of the field effect transistor Q33 and the drain electrode D of the field effect transistor Q34 are both connected to one end of the inductor L32; The other end of the inductor L31 is respectively connected to one end of the capacitor C31, one end of the resistor R30 and one end of the third voltage output terminal Vout3; The other end of the inductor L32 is connected to the other end of the capacitor C31 and one end of the resistor R30 respectively; The other end of the inductor L32 is connected to one end of the third voltage output terminal Vout3 .

6. The ACAC power supply module for railway signal power supply panel according to claim 5, characterized in that: Field effect transistors Q31 to Q34 are all NMOS field effect transistors.

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