Power supply device of lighting system

Abstract

The invention discloses a power supply device of a lighting system, which belongs to the field of regional lighting system design, and comprises a control module, an alternating current-direct current conversion module, a plurality of direct current-direct current conversion modules and a positive and negative voltage direct current bus, the control module is connected with the alternating current-direct current conversion module, and the input end of the alternating current-direct current conversion module is connected with three-phase alternating current; the output ends of the alternating current-direct current conversion modules are connected with the positive and negative voltage direct current bus, the positive and negative voltage direct current bus comprises a positive voltage terminal, a negative voltage terminal and a ground terminal, the input end of each direct current-direct current conversion module is connected with the positive voltage terminal and the negative voltage terminal, and the shell of each direct current-direct current conversion module is connected with the ground terminal. An output mode of the positive and negative voltage direct current bus is adopted, the insulation grade of an output direct current cable can be reduced by half, regional installation and implementation are achieved, cost is low, regional targeted construction is achieved, flexibility and convenience are achieved, and follow-up upgrading and maintenance are easy.

Description

Technical Field

[0001] This invention relates to the field of area lighting system design, and in particular to a power supply device for a lighting system. Background Technology

[0002] Plants need sunlight for photosynthesis. Artificial greenhouse cultivation can improve plant yield and quality. Artificial cultivation requires control over the lighting time and intensity for plants. Currently, the commonly used regional lighting control schemes are single-phase independent AC-DC conversion drive and high-voltage DC centralized power supply.

[0003] In the control scheme of single-phase independent AC-DC conversion drive, the PE value of each power supply is low under light load and no-load, resulting in a large amount of reactive power, which causes huge waste and high design, construction and subsequent maintenance costs.

[0004] In the control scheme of centralized high-voltage DC power supply, the high-voltage DC bus insulation level is required, each DC-DC conversion module is isolated, and each module needs a dimming control port, resulting in high cost and poor reliability. The entire area needs to be designed as a whole, which leads to high design and construction costs and a long construction period. Summary of the Invention

[0005] The present invention aims to provide a power supply device for a lighting system.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A power supply device for a lighting system includes a control module, an AC-DC conversion module, multiple DC-DC conversion modules, and positive and negative voltage DC buses. The control module is connected to the AC-DC conversion modules. The input terminals of the AC-DC conversion modules are connected to three-phase AC power, and the output terminals of the AC-DC conversion modules are connected to the positive and negative voltage DC buses. The positive and negative voltage DC buses include positive voltage terminals, negative voltage terminals, and ground terminals. The input terminal of each DC-DC conversion module is connected to the positive voltage terminal and the negative voltage terminal, and the housing of each DC-DC conversion module is connected to the ground terminal.

[0008] The power supply device for the lighting system further includes a bus current detection module and multiple branch current detection modules. The output terminal of the AC-DC conversion module is connected to the input terminal of the bus current detection module. The output terminal of the bus current detection module is connected to the positive and negative voltage DC bus. The input terminal of each branch current detection module is connected to the positive and negative voltage DC bus. The output terminal of each branch current detection module is connected to the input terminal of a DC-DC conversion module.

[0009] The operating timing sequence of the bus current detection module and the multiple branch current detection modules includes...

[0010] Step S1: When any branch current detection module detects an arcing fault in the input current of the corresponding DC-DC converter module, the DC-DC converter module stops working.

[0011] Step S2: When the bus current detection module detects an arcing fault in the output current of the AC-DC conversion module, the AC-DC conversion module stops working.

[0012] Step S3: Report the arcing fault to the control module.

[0013] In one specific embodiment, the AC-DC conversion module includes an AC-DC conversion circuit and a DC-DC conversion circuit. The input terminal of the AC-DC conversion circuit is connected to a three-phase AC power supply, the output terminal of the AC-DC conversion circuit is connected to the input terminal of the DC-DC conversion circuit, and the output terminal of the DC-DC conversion circuit is connected to the positive and negative voltage DC bus.

[0014] In one specific embodiment, the output terminal of the above-mentioned AC-DC conversion circuit includes a first terminal, a second terminal and a third terminal. The first terminal outputs the positive maximum value of the three-phase AC power, the second terminal outputs the intermediate value of the three-phase AC power, and the third terminal outputs the reverse maximum value of the three-phase AC power.

[0015] In one specific embodiment, the AC-DC conversion circuit includes a three-phase rectifier unit, an A-phase bidirectional switch, a B-phase bidirectional switch, and a C-phase bidirectional switch. The three-phase rectifier unit includes an A-phase bridge arm, a B-phase bridge arm, and a C-phase bridge arm. The two ends of the A-phase bridge arm, the B-phase bridge arm, and the C-phase bridge arm connected in parallel are the first terminal and the third terminal. The three-phase AC power is connected to the midpoint of the bridge arm of the A-phase bridge arm, the B-phase bridge arm, and the C-phase bridge arm, respectively. The first end of the A-phase bidirectional switch, the B-phase bidirectional switch, and the C-phase bidirectional switch is connected to the midpoint of the bridge arm of the A-phase bridge arm, the B-phase bridge arm, and the C-phase bridge arm, respectively. The second end of the A-phase bidirectional switch, the B-phase bidirectional switch, and the C-phase bidirectional switch is connected to form the second terminal.

[0016] In one specific embodiment, the DC-DC conversion circuit includes a three-level bridge unit, an LLC resonant converter unit, and a rectifier filter unit, wherein the three-level bridge unit, the LLC resonant converter unit, and the rectifier filter unit are connected in parallel in sequence.

[0017] In one specific embodiment, the DC-DC conversion module includes a first diode, a first inductor, a first capacitor, and a first switch. The cathode of the first diode is connected to the positive voltage terminal, the anode of the first diode is connected to the first terminal of the first switch, the second terminal of the first switch is connected to the negative voltage terminal, the first terminal of the first inductor is connected to the anode of the first diode, the second terminal of the first inductor is connected to the first terminal of the first capacitor, and the second terminal of the first capacitor is connected to the cathode of the first diode.

[0018] In one specific embodiment, the DC-DC conversion module includes a second diode, a second capacitor, a second switch, and a first transformer. The first end of the primary winding of the first transformer is connected to the positive voltage terminal. The second end of the primary winding of the first transformer is connected to the first end of the second switch. The second end of the second switch is connected to the negative voltage terminal. The first end of the secondary winding of the first transformer is connected to the anode of the second diode. The second end of the secondary winding of the first transformer is connected to the first end of the second capacitor. The second end of the second capacitor is connected to the cathode of the second diode.

[0019] The beneficial effects of the power supply device for the lighting system of the present invention are that it can achieve uniform lighting in the planting area, adopts a unique positive and negative bus DC output method, which can reduce the insulation level of the output DC cable by half; it can use traditional three-core AC cables, which is low cost; it does not require rewiring the power supply, and can directly utilize existing AC cables; it is easy to install and implement in a specific area, with low construction costs, targeted construction in a specific area, flexibility and convenience, and easy subsequent upgrades and maintenance.

[0020] To make the above-mentioned features and advantages of the invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the power supply device for a lighting system according to the present invention.

[0022] Figure 2 for Figure 1 Circuit diagram of the AC-DC conversion module.

[0023] Figure 3 for Figure 1 The circuit diagram shows a non-isolated topology DC-DC converter module.

[0024] Figure 4 for Figure 1 The circuit diagram shows a DC-DC converter module with an isolated topology.

[0025] In the accompanying drawings, similar reference numerals refer to the same elements.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1-AC-DC conversion module; 11-AC-DC conversion circuit; 12-DC-DC conversion circuit; 121-Three-level bridge unit; 122-LLC resonant unit; 123-Rectifier and filter unit; 21-First DC-DC conversion module; 22-Second DC-DC conversion module; 2n-Nth DC-DC conversion module; 3-Control module; 41-First branch current detection module; 42-Second branch current detection module; 4n-Nth branch current detection module; 5-Bus current detection module. Detailed Implementation

[0028] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] Figure 1 This is a schematic diagram of the power supply device for a lighting system according to the present invention. It includes an AC-DC conversion module 1, a control module 3, multiple DC-DC conversion modules, and positive and negative voltage DC buses. The control module 3 is connected to the AC-DC conversion module 1. The input terminal of the AC-DC conversion module 1 is connected to three-phase AC power. The output terminal of the AC-DC conversion module 1 is connected to the positive and negative voltage DC buses. The positive and negative voltage DC buses include a positive voltage terminal, a negative voltage terminal, and a ground terminal. The input terminal of each DC-DC conversion module is connected to the positive voltage terminal and the negative voltage terminal. The housing of each DC-DC conversion module is connected to the ground terminal. The output terminal of each DC-DC conversion module is connected to a lighting load.

[0030] The control module 3 controls the AC-DC conversion module 1 to adjust the voltage on the positive and negative DC bus to vary within a certain range; the DC-DC conversion module reads the voltage of the positive and negative DC bus as the input voltage, and controls the output current of the DC-DC conversion module according to the information of the input voltage, thereby realizing the lighting control of the lighting load.

[0031] The power supply device for the lighting system further includes a bus current detection module 5 and multiple branch current detection modules. The input terminal of the bus current detection module 5 is connected to the output terminal of the AC-DC conversion module 1, and the output terminal of the bus current detection module 5 is connected to the positive and negative voltage DC bus. The bus current detection module 5 performs arc detection on the output current of the AC-DC conversion module 1.

[0032] More specifically, the plurality of DC-DC conversion modules include a first DC-DC conversion module 21, a second DC-DC conversion module 22, up to the nth DC-DC conversion module 2n, and the plurality of lighting loads include a first lighting load H1, a second lighting load H2, up to the nth lighting load H n The output of the first DC-DC converter 21 is connected to the first lighting load H1, the output of the second DC-DC converter 22 is connected to the second lighting load H2, and so on, until the output of the nth DC-DC converter 2n is connected to the nth lighting load H1. n .

[0033] More specifically, the plurality of DC-DC conversion modules include a first branch current detection module 41, a second branch current detection module 42, and so on up to an nth branch current detection module 4n. The input terminal of the first branch current detection module 41 is connected to the positive and negative voltage DC bus, and the output terminal of the first branch current detection module 41 is connected to the input terminal of the first DC-DC conversion module 21 to perform arc detection on the input current of the first DC-DC conversion module 21. The input terminal of the second branch current detection module 42 is connected to the positive and negative voltage DC bus, and the output terminal of the second branch current detection module 42 is connected to the input terminal of the second DC-DC conversion module 22 to perform arc detection on the input current of the second DC-DC conversion module 22. And so on, until the input terminal of the nth branch current detection module 4n is connected to the positive and negative voltage DC bus, and the output terminal of the nth branch current detection module 4n is connected to the input terminal of the nth DC-DC conversion module 2n to perform arc detection on the input current of the nth DC-DC conversion module 2n.

[0034] The operating timing sequence of the bus current detection module 5 and the multiple branch current detection modules includes...

[0035] Step S1: When any branch current detection module detects an arcing fault in the input current of the corresponding DC-DC converter module, the DC-DC converter module stops working.

[0036] Step S2: When the bus current detection module 5 detects an arcing fault in the output current of the AC-DC conversion module 1, the AC-DC conversion module 1 stops working.

[0037] Step S3: Report the arcing fault to the control module.

[0038] like Figure 2 As shown Figure 1 The circuit diagram of the AC-DC conversion module 1 is shown. The AC-DC conversion module 1 includes an AC-DC conversion circuit 11 and a DC-DC conversion circuit 12. The input terminal of the AC-DC conversion circuit 11 is connected to a three-phase AC power supply. The output terminal of the AC-DC conversion circuit 11 is connected to the input terminal of the DC-DC conversion circuit 12. The output terminal of the DC-DC conversion circuit 12 is connected to the positive and negative voltage DC bus.

[0039] The output terminals of the AC-DC conversion circuit 11 include a first terminal P, a second terminal Y, and a third terminal N. The first terminal P outputs the positive maximum value of the three-phase AC power, the second terminal Y outputs the intermediate value of the three-phase AC power, and the third terminal N outputs the reverse maximum value of the three-phase AC power.

[0040] The AC-DC conversion circuit 11 includes a three-phase rectifier unit and a bidirectional switch S. ya Two-way switch S yb and bidirectional switch S yc The three-phase rectifier unit includes an A-phase bridge arm, a B-phase bridge arm, and a C-phase bridge arm. The two ends of the parallel connection of the A-phase bridge arm, the B-phase bridge arm, and the C-phase bridge arm are the first terminal P and the third terminal N. The three-phase AC power is connected to the midpoints of the A-phase bridge arm, the B-phase bridge arm, and the C-phase bridge arm, respectively. The bidirectional switch S... ya The bidirectional switch S yb and the bidirectional switch S yc The first end is connected to the midpoint of the bridge arm of phase A, phase B, and phase C respectively, and the bidirectional switch S ya The bidirectional switch S yb and the bidirectional switch S yc The second terminal Y is formed by connecting the second end in parallel.

[0041] More specifically, the bidirectional switch S ya S yb S yc At the moment when the two phase voltages intersect, a low-frequency switching is initiated. The phase with the larger absolute value of its voltage amplitude is switched off bidirectionally, while the phase with the smaller amplitude is switched on bidirectionally. Thus, the phase with the larger positive voltage amplitude is connected to the first terminal P through the upper diode of the three-phase rectifier unit, and the phase with the larger negative voltage amplitude is connected to the third terminal N through the lower diode of the three-phase rectifier unit. The remaining phase is connected through the conducting bidirectional switch S. ya / Syb / S yc Connect the second terminal Y.

[0042] More specifically, the DC-DC conversion circuit 12 includes a three-level bridge unit 121, an LLC resonant converter unit 122, and a rectifier and filter unit 123, wherein the three-level bridge unit 121, the LLC resonant converter unit 122, and the rectifier and filter unit 123 are connected in parallel in sequence.

[0043] The input terminal of the DC-DC converter circuit 12 is connected to the first terminal P, the second terminal Y and the third terminal N; the DC-DC converter circuit 12 outputs three-terminal voltage signals (+V0, PE, -V0) to the positive and negative voltage DC bus, and the positive and negative voltage DC bus uses an existing three-core cable as the current transmission carrier.

[0044] The three-level bridge unit 121 includes switches S1, S2, S3, S4, bidirectional switches S5-S6, and bidirectional switches S7-S8. The first ends of switches S1 and S3 are connected to the first terminal P. The second ends of switches S2 and S4 are connected to the third terminal N. The second end of switch S1 is connected to the first end of switch S2. The second end of switch S3 is connected to the first end of switch S4. The second end of switch S1 is connected to the second end of bidirectional switches S5-S6. The second end of switch S3 is connected to the second end of bidirectional switches S7-S8. The first ends of bidirectional switches S5-S6 and S7-S8 are connected to the second terminal Y.

[0045] The LLC resonant converter unit 122 includes an inductor L r Capacitor C r And transformer T2, the inductor L r The capacitor C r The two ends of the primary winding of the transformer T2 are connected in series with the second ends of the bidirectional switches S5-S6 and S7-S8, and the transformer includes a first secondary winding and a second secondary winding.

[0046] The rectifier and filter unit 123 includes a first rectifier filter and a second rectifier filter. The input terminal of the first rectifier filter is connected in parallel with the first secondary winding of the transformer T2, and the input terminal of the second rectifier filter is connected in parallel with the second secondary winding of the transformer T2. The positive output terminal of the first rectifier filter is connected to the positive voltage terminal of the positive and negative DC bus. The negative output terminal of the first rectifier filter is connected to the positive output terminal of the second rectifier filter and then connected to the ground terminal of the positive and negative DC bus. The negative output terminal of the second rectifier filter is connected to the negative voltage terminal of the positive and negative DC bus.

[0047] Optionally, the first rectifier filter includes diodes D1, D2, D3, and D4, wherein diodes D1, D2, D3, and D4 constitute a full-bridge rectifier topology.

[0048] Optionally, the second rectifier filter includes diodes D5, D6, D7, and D8, wherein diodes D5, D6, D7, and D8 constitute a full-bridge rectifier topology.

[0049] In one specific embodiment, the DC-DC conversion module may be a non-isolated topology. For example... Figure 3 As shown Figure 1 The schematic diagram of the DC-DC converter module is a non-isolated topology circuit, including a switch Q1, a diode D9, an inductor L1, a capacitor C1, and a housing W1. The cathode of diode D9 is connected to the positive voltage terminal, the anode of diode D9 is connected to the first terminal of switch Q1, and the second terminal of switch Q1 is connected to the negative voltage terminal. The first terminal of inductor L1 is connected to the anode of diode D9, the second terminal of inductor L1 is connected to the first terminal of capacitor C1, and the second terminal of capacitor C1 is connected to the cathode of diode D9. The housing W1 is connected to the ground terminal PE. The switch Q1, diode D9, inductor L1, and capacitor C1 are assembled inside the housing W1. The nth lighting load H is connected in parallel across the terminals of capacitor C1. n .

[0050] In one specific embodiment, the DC-DC conversion module may be an isolated topology. For example... Figure 4 As shown Figure 1 The circuit diagram of the DC-DC converter module is an isolated topology, including switch Q2, transformer T1, and diode D. 10The transformer T1 has a capacitor C2 and a casing W2; the first end of the primary winding of the transformer T1 is connected to the positive voltage terminal, the second end of the primary winding of the transformer T1 is connected to the first end of the switch Q2, the second end of the switch Q2 is connected to the negative voltage terminal, and the first end of the secondary winding of the transformer T1 is connected to the diode D. 10 The anode of the transformer T1 is connected to the second terminal of the secondary winding, which is connected to the first terminal of the capacitor C2. The second terminal of the capacitor C2 is connected to the diode D. 10 The cathode is connected, the housing W2 is connected to the ground terminal PE, the switch Q2, the transformer T1, and the diode D are connected. 10 The capacitor C2 is assembled inside the housing W2, and the nth lighting load H is connected in parallel across the terminals of the capacitor C2. n .

[0051] In a specific embodiment, the control module of the present invention can be a cloud system or a host computer. The control module can communicate with and control the AC-DC conversion module via wired or wireless means.

[0052] The beneficial effects of the power supply device for a lighting system proposed in this invention are as follows:

[0053] It adopts a unique positive and negative bus DC output method, which can reduce the insulation level of the output DC cable by half; it can use traditional three-core AC cables, which is low cost; it does not require rewiring the power supply, and can directly utilize existing AC cables; it is easy to install and implement in a specific area, with low construction costs, flexible and convenient targeted construction, and easy subsequent upgrades and maintenance.

[0054] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A power supply device for a lighting system, characterized in that: It includes a control module, an AC-DC conversion module, multiple DC-DC conversion modules, and a positive and negative voltage DC bus. The control module is connected to the AC-DC conversion module. The input end of the AC-DC conversion module is connected to three-phase AC power. The output end of the AC-DC conversion module is connected to the positive and negative voltage DC bus. The positive and negative voltage DC bus includes a positive voltage terminal, a negative voltage terminal, and a ground terminal. The input end of each DC-DC conversion module is connected to the positive voltage terminal and the negative voltage terminal. The housing of each DC-DC conversion module is connected to the ground terminal.

2. A power supply device for a lighting system as claimed in claim 1, characterized in that: It also includes a bus current detection module and multiple branch current detection modules, the output end of the AC-DC conversion module is connected to the input end of the bus current detection module, the output end of the bus current detection module is connected to the positive and negative voltage DC bus, the input end of each branch current detection module is connected to the positive and negative voltage DC bus, and the output end of each branch current detection module is respectively connected to an input end of the DC-DC conversion module.

3. A power supply device for a lighting system as claimed in claim 2, characterized in that: The working sequence of the bus current detection module and the plurality of branch current detection modules includes: Step S1, when any branch current detection module detects that an arc fault occurs in the input current of the corresponding DC-DC conversion module, the DC-DC conversion module stops working; Step S2, when the bus current detection module detects that an arc fault occurs in the output current of the AC-DC conversion module, the AC-DC conversion module stops working; Step S3, reporting the arcing fault to a control module.

4. A power supply device for a lighting system as claimed in claim 1, characterized in that: The AC-DC conversion module includes an AC-DC conversion circuit and a DC-DC conversion circuit. The input end of the AC-DC conversion circuit is connected to three-phase AC power, the output end of the AC-DC conversion circuit is connected to the input end of the DC-DC conversion circuit, and the output end of the DC-DC conversion circuit is connected to the positive and negative voltage DC bus.

5. A power supply device for a lighting system as claimed in claim 4, characterized in that: The output end of the AC-DC conversion circuit includes a first terminal, a second terminal and a third terminal, the first terminal outputs the forward maximum value of the three-phase AC power, the second terminal outputs the middle value of the three-phase AC power, and the third terminal outputs the reverse maximum value of the three-phase AC power; The AC-DC conversion circuit includes a three-phase rectifier unit, an A-phase bidirectional switch, a B-phase bidirectional switch and a C-phase bidirectional switch. The three-phase rectifier unit includes an A-phase bridge arm, a B-phase bridge arm and a C-phase bridge arm. The two ends of the A-phase bridge arm, the B-phase bridge arm and the C-phase bridge arm after being connected in parallel are the first terminal and the third terminal. The three-phase AC power is respectively connected to the midpoints of the A-phase bridge arm, the B-phase bridge arm and the C-phase bridge arm. The first ends of the A-phase bidirectional switch, the B-phase bidirectional switch and the C-phase bidirectional switch are respectively connected to the midpoints of the A-phase bridge arm, the B-phase bridge arm and the C-phase bridge arm. The second ends of the A-phase bidirectional switch, the B-phase bidirectional switch and the C-phase bidirectional switch are connected to the second terminal.

6. A power supply device for a lighting system as claimed in claim 4, characterized in that: The DC-DC conversion circuit comprises a three-level bridge unit, an LLC resonant conversion unit, and a rectifier and filter unit, and the three-level bridge unit, the LLC resonant conversion unit, and the rectifier and filter unit are sequentially connected in parallel.

7. A power supply device for a lighting system as claimed in claim 1, characterized in that: The DC-DC conversion module includes a first diode, a first inductor, a first capacitor, and a first switch, wherein a cathode of the first diode is connected to the positive voltage terminal, an anode of the first diode is connected to a first end of the first switch, a second end of the first switch is connected to the negative voltage terminal, a first end of the first inductor is connected to an anode of the first diode, a second end of the first inductor is connected to a first end of the first capacitor, and a second end of the first capacitor is connected to a cathode of the first diode.

8. A power supply device for a lighting system as claimed in claim 1, characterized in that: The DC-DC conversion module includes a second diode, a second capacitor, a second switch, and a first transformer, wherein the first end of the primary winding of the first transformer is connected to the positive voltage terminal, the second end of the primary winding of the first transformer is connected to the first end of the second switch, the second end of the second switch is connected to the negative voltage terminal, the first end of the secondary winding of the first transformer is connected to the anode of the second diode, the second end of the secondary winding of the first transformer is connected to the first end of the second capacitor, and the second end of the second capacitor is connected to the cathode of the second diode.

Images