Hybrid power distribution box and unmanned aerial vehicle power distribution system

Abstract

The invention discloses a hybrid power distribution box and an unmanned aerial vehicle power distribution system, and the power distribution box is configured to comprise a mechanical contact type switch which is used as a control switch for power distribution of a power distribution channel where fuses and initiating explosive devices are located, and is configured to comprise a safety switch, a triode Q1, a relay J1, a triode Q2 and a relay J2; the MOSFET solid switch serves as a control switch for power distribution of a power distribution channel which is short in response time, small in load current, high in overvoltage requirement and low in on resistance and is configured to comprise an optocoupler and an MOS tube Q4. The voltage conversion module is used for providing various voltages; and the bus bar is connected with the output of the voltage conversion module, and different voltage bus bars are formed according to different voltages output by the voltage conversion module. According to the invention, bus bar power distribution, mechanical contact type switch power distribution and MOSEFT solid switch power distribution are configured, power distribution according to different load power distribution requirements is realized, power distribution of loads with different performances is satisfied, power distribution optimization is realized, and the cost performance and power density of products are improved.

Description

Technical Field

[0001] The invention relates to a hybrid power distribution box and a UAV power distribution system. Background Art

[0002] The current system battery power distribution adopts solid-state or mechanical contact output. The disadvantage is that it cannot achieve the best configuration according to the diversity of load types. Pure solid-state power distribution may cause ignition load malfunction, while mechanical contact power distribution will cause the product to be bloated or insufficient transient overload capacity will cause contact ablation and bonding, and the appearance is large and bulky. Summary of the invention

[0003] The purpose of the present invention is to provide a hybrid power distribution box, which can meet the power distribution needs of loads with different performances and improve the correct power distribution performance to a certain extent.

[0004] The hybrid distribution box is configured to include:

[0005] The mechanical contact switch, as a control switch for distributing power to the power distribution channel where the fuse and the explosive device are located, is configured to include a safety switch, a transistor Q1, a relay J1, a transistor Q2 and a relay J2;

[0006] The MOSFET solid-state switch, as a control switch for distributing power to a distribution channel with fast response time, small load current, high overvoltage requirement, and low on-resistance, is configured to include an optocoupler and a MOS tube Q4;

[0007] A voltage conversion module for providing multiple voltages;

[0008] The bus bar is connected to the output of the voltage conversion module, and different voltage bus bars are formed according to different voltages output by the voltage conversion module;

[0009] When distributing power to the load, the load is directly connected to the bus bar, connected to the bus bar through a mechanical contact switch, or connected to the bus bar through a MOSFET solid switch; the power supply is connected to the distribution box, converted into a target voltage by a voltage conversion module, and connected to the bus bar to directly supply power to the load; the fuse is disconnected, the transistor Q1 is cut off, and the voltage on the bus bar is distributed to the relay J2 through the relay J1; the control signal on the gate of the transistor Q2 turns on the transistor Q2, and the relay J2 is turned on to distribute power to the load; the voltage on the bus bar is connected to the optocoupler, which is turned on under the action of the control signal and connects the voltage to the gate of the MOS tube Q4 as a gate bias to turn on the MOS tube Q4, and the voltage connected to the drain of the MOS tube Q4 is used for load distribution;

[0010] When power distribution is not required with a mechanical contact switch, the safety switch is turned on, the transistor Q1 is turned on, the relay J1 is actuated, and the power distribution is cut off; or, the safety switch is turned off, the transistor Q1 is turned off, the control signal on the gate of the transistor Q2 is an invalid signal, the transistor Q2 is turned off, the relay J2 is turned off, and the power distribution is cut off; or, the safety switch is turned on, the transistor Q1 is turned on, the relay J1 is actuated, and at the same time, the control signal on the gate of the transistor Q2 is an invalid signal, the transistor Q2 is turned off, the relay J2 is turned off, and the power distribution is cut off;

[0011] When there is no need for MOSFET solid-state switch power distribution, the control signal controls the optocoupler to cut off, the MOS tube Q4 to cut off, and the power distribution is cut off;

[0012] When busbar power distribution or distribution box power distribution is not required, cut off the power supply to the distribution box.

[0013] In some embodiments, the voltage on the bus bar is also distributed to the drain of the MOS tube Q4 after passing through the relay J1. When the MOSFET solid-state switch is not needed for power distribution, the safety switch is turned on, the transistor Q1 is turned on, and the relay J1 is actuated to cut off the power distribution to the MOS tube Q4, thereby cutting off the power distribution; or, the control signal on the optocoupler is invalid, so that the optocoupler is cut off, and at the same time the safety switch is turned on, the transistor Q1 is turned on, and the relay J1 is actuated to cut off the power distribution to the MOS tube Q4, thereby cutting off the power distribution.

[0014] In some embodiments, the voltage on the bus bar is distributed to the load after passing through the relay J1. When the relay J1 is not needed to distribute power to the load, the safety switch is turned on, the transistor Q1 is turned on, the relay J1 is actuated, and the power distribution is cut off.

[0015] In some embodiments, the base of transistor Q1 is connected to the anode of diode D1 via resistor R1, and is connected to the emitter of transistor Q1 via resistor R2; the cathode of diode D1 is connected to the anode of diode D2 and is grounded, the cathode of diode D2 is connected to the collector of transistor Q1, and is grounded via the coil of relay J1, forming a structure connected in parallel with the coil of relay J1; the cathode of diode D1 and the anode of diode D2 serve as the safety switch connection terminals.

[0016] In some embodiments, the base of the transistor Q2 is connected to the anode of the diode D3 via the resistor R3, and is connected to the emitter of the transistor Q2 via the resistor R4; the cathode of the diode D3 serves as the access terminal of the control signal; the collector of the transistor Q2 is connected to the cathode of the diode D4, and is grounded via the coil of the relay J2, and the anode of the diode D4 is grounded, forming a structure connected in parallel with the coil of the relay J2.

[0017] In some embodiments, the optocoupler output is connected to the gate of the MOS tube Q4 via the diode D6 and the resistor R7, and the optocoupler output is also connected to the base of the transistor Q12, the emitter of the transistor Q12 is connected to the cathode of the diode D6, the collector is connected to the optocoupler output -, the source of the MOS tube Q4, and is grounded via the resistor R8; the other end of the resistor R8 is connected to the anode of the Zener diode Z3, and the cathode of the Zener diode Z3 is connected to one end of the resistor R7 connected to the cathode of the diode D6; the ground end of the resistor R8 is also connected to the anode of the diode D7, and the cathode of the diode D7 is connected to the source of the MOS tube Q4.

[0018] In some implementations, the power supplied to the optocoupler control terminal is filtered and then connected via resistor R5, resistor R6 is connected in parallel at both ends of resistor R5, the optocoupler control terminal is also connected to the anode of diode D5 via capacitor C2, and the cathode of diode D5 is used for control signal access.

[0019] In some embodiments, the distribution box is also configured to collect a voltage sampling circuit for collecting the voltage on the bus bar, and the voltage sampling circuit includes a precision linear optocoupler and an amplifier, and the output of the precision linear optocoupler is connected to the in-phase input terminal and the reverse input terminal of the amplifier via resistors R13 and R14, respectively, and the amplifier outputs the sampling result; a resistor R15 and a capacitor C9 are respectively connected in series between the reverse input terminal and the output terminal of the amplifier.

[0020] In some embodiments, the V IN The voltage at the end is between 1.5V and 2.5V.

[0021] In some embodiments, the V provided to the precision linear optocoupler IN The power supply at the end is connected after being divided by resistors R11 and R10; the amplifier's in-phase input end is also grounded via resistor R16.

[0022] In some embodiments, the power distribution box is further configured to be used for a current sampling circuit for collecting current on the bus bar, the current sampling circuit includes a Hall sensor with a reversely connected current input terminal, and the Hall sensor outputs a sampling result.

[0023] In some embodiments, the distribution box includes a shell and a printed circuit board assembled in the shell, the bottom plate of the shell is a heat dissipation bottom plate, and the printed circuit board is assembled together with the heat dissipation bottom plate through a support column and a screw assembly; a mechanical contact switch, a MOSFET solid switch, a voltage conversion module, and a bus bar are arranged on the printed circuit board, and an input connector and an output connector are assembled on the shell, the power supply is connected to the voltage conversion module via the input connector, the mechanical contact switch, the MOSFET solid switch, and the bus bar are electrically connected to the output connector respectively, and the output connector serves as a connection port connected to the load.

[0024] In some embodiments, the heat dissipation base plate is a fence-type heat dissipation tooth structure.

[0025] In some embodiments, the power distribution box is used in a drone, and the heat dissipation groove direction is along the flight direction of the drone.

[0026] The second purpose of the present invention is to provide a UAV power distribution system, which includes a UAV central control system and a distribution box. The UAV central control system generates a control signal and connects to the distribution box to control the conduction and cutoff of the optocoupler and the transistor Q2. The distribution box distributes power to the power-requiring loads on the UAV; the distribution box is the distribution box provided by the present invention.

[0027] The present invention includes the following beneficial effects:

[0028] 1) Optimized combination of solid power distribution and electromagnetic power distribution: The present invention configures busbar power distribution, mechanical contact switch power distribution and MOSSEFT solid switch power distribution, realizing power distribution according to different load power distribution requirements (mechanical contact electromagnetic relays are used for fuses, pyrotechnics, and insurance control switches. Electromagnetic relays can withstand short-term overcurrent shocks several times the rated current due to their slow response, no leakage current, and long overload time, and can absorb high-frequency spike interference signals to avoid output malfunctions. For distribution channels with fast response time, small load current, high overvoltage requirements, and low on-resistance, high-voltage MOSFETs are used as power output devices), meeting the power distribution of loads with different performances, realizing the optimization of power distribution, improving the cost performance and power density of the product, and reducing the volume and weight of the product to a certain extent.

[0029] 2) Reliability of power distribution. Dual control of safety switch and control signal is adopted. Power distribution is carried out only when both the safety switch and the control signal are valid, which ensures the correctness of power distribution and avoids incorrect power distribution due to incorrect operation of the safety switch or the control signal. Furthermore, a series structure of safety switch plus diode switch control is adopted. Power distribution can only be carried out when the safety switch is correctly turned on and the diode is triggered to turn on, further ensuring the correctness of power distribution. At the same time, an anti-reverse diode is connected in series on the ground / open control line to prevent high-level signals from entering the circuit and causing false triggering.

[0030] 3) This distribution box adopts a ground / open control circuit structure, which improves the anti-interference ability of the distribution box.

[0031] 4) This distribution box is constructed with discrete components such as electromagnetic relays, optocouplers, triodes, diodes, and field effect transistors, and the outputs of the mechanical contact switch and MOSFET solid-state switch are independent, with low coupling between each other, and automatic isolation can be achieved in the event of a fault.

[0032] 5) The distribution box is equipped with a voltage / current acquisition circuit to collect the voltage / current on each bus bar in real time, and provide the voltage / current conditions on each bus bar under the power distribution state. It can be effectively monitored in conjunction with the control system, and can assist in monitoring the working status of the distribution box and understand the status of the distribution box, with a high reliability coefficient.

[0033] 6) Heat dissipation efficiency: The bottom plate of the housing of the distribution box is configured as a heat dissipation base plate. No additional external heat dissipation device is required. Effective heat dissipation can be achieved by connecting high heat dissipation components or functional modules / circuits to the heat dissipation base plate through thermal pads.

[0034] 7) The busbars, mechanical contact switches and MOSFET solid switches in this distribution box are completely electrically isolated, and the output of each channel is ground / open control, which has strong resistance to external interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings herein are incorporated into and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0036] Figure 1 A schematic diagram of the appearance structure of the power distribution box provided by the present invention;

[0037] Figure 2 A schematic diagram of the internal structure of the power distribution box provided by the present invention;

[0038] Figure 3 Schematic diagram of the heat dissipation base structure of the power distribution box provided by the present invention

[0039] Figure 4 A schematic diagram of the structure of a printed circuit board of a power distribution box provided by the present invention;

[0040] Figure 5 A circuit diagram of the mechanical contact switch described in the present invention;

[0041] Figure 6 A circuit diagram of a MOSFET solid-state switch described in the present invention;

[0042] Figure 7 A circuit structure diagram of the voltage acquisition circuit described in the present invention;

[0043] Figure 8 The circuit structure diagram of the current acquisition current described in the present invention;

[0044] Fig. 9The UAV power distribution network topology diagram and power distribution diagram provided by the present invention;

[0045] Fig.10 This is a circuit structure diagram when the ground / open control signal described in the present invention is open. DETAILED DESCRIPTION

[0046] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the invention will be more comprehensive and complete and fully convey the concept of the example embodiments to those skilled in the art.

[0047] The structure of the distribution box provided by the present invention is Figure 1-4 It is exemplarily shown that a housing 1 and a printed circuit board 2 assembled in an assembly cavity formed by the housing 1 are configured, and the printed circuit board 2 is used to realize the construction of a functional circuit.

[0048] The housing 1 includes a heat dissipation base plate 11, a left side plate 12, a front panel 13, a cover plate 14, a right side plate 15, and a rear panel 16. The heat dissipation base plate 11, the left side plate 12, the front side plate 13, the cover plate 14, the right side plate 15, and the rear panel 16 are assembled using countersunk screws. The printed circuit board 2 is assembled in the housing 1. For heat dissipation, it is suspended on the heat dissipation base plate 11 through a support column 3 and a screw assembly 4. A heat dissipation channel is formed between the printed circuit board 2 and the heat dissipation base plate 11 for heat dissipation.

[0049] To improve the heat dissipation performance, the support column 3 is made of heat-conducting material to form a heat-conducting support column. The cooperation of the heat dissipation channel, the heat dissipation base plate and the heat-conducting column improves the heat dissipation performance of the distribution box. No additional heat dissipation equipment is required, which reduces the volume and weight of the distribution box.

[0050] Alternatively, the printed circuit board 2 is directly mounted on the heat dissipation base plate 11 via a thermal pad.

[0051] The functional circuit constructed on the printed circuit board 2 is used to realize power distribution, and the housing 1 is provided with an input connector 5 and an output connector 6 as components for electrical connection with external devices. The functional circuit is configured to include:

[0052] The mechanical contact switch, as a control switch for distributing power to the power distribution channel where the fuse and the explosive device are located, is configured to include a safety switch, a transistor Q1, a relay J1, a transistor Q2 and a relay J2;

[0053] The MOSFET solid-state switch, as a control switch for distributing power to a power distribution channel with fast response time, small load current, high overvoltage requirement, and low on-resistance, is configured to include an optocoupler IC1 and a MOS tube Q4;

[0054] The voltage conversion module is used to convert the power supply into a target voltage and is configured to provide multiple voltages, such as converting a 100V power supply into 28V, and then converting 28V into 8.5V and 5V voltages;

[0055] The bus bar and the voltage conversion module output form different voltage buses according to the different voltages output by the voltage conversion module. For example, the bus bar is connected to the 28V output of the voltage conversion module to form a 28V bus bar; connected to the 8.5V output to form an 8.5V bus bar; connected to the 5V voltage output to form a 5V bus bar; the voltage conversion module is configured according to product requirements to meet the required output voltage; the voltage conversion module output is used as a distribution power supply, and according to the load performance, it is directly distributed to the load through the bus bar, or connected to the bus bar through a mechanical contact switch, or connected to the bus bar through a MOSFET solid switch; when the mechanical contact switch / MOSFET solid switch is turned on, the power on the bus bar is provided to the load through the switch to distribute power to the load; when disconnected, no power is distributed to the load.

[0056] The combination of busbars, mechanical contact switches, and MOSFET solid switches not only meets the power distribution requirements of different load performances (mechanical contact electromagnetic relays are used for fuses, pyrotechnics, and insurance control switches. Electromagnetic relays can withstand short-term overcurrent shocks several times the rated current due to their slow response, no leakage current, and long overload time. They can also absorb high-frequency spike interference signals to avoid output malfunctions; for distribution channels with fast response time, small load current, high overvoltage requirements, and low on-resistance, high-voltage MOSFETs are used as power output devices for power distribution; loads that do not belong to the above attributes can be directly distributed using busbars), and by controlling the conduction and disconnection of mechanical contact switches / MOSFET solid switches, a power distribution plan for specific loads is implemented, realizing multi-combination power distribution; and the busbars, mechanical contact switches, and MOSFET solid switches are independently arranged with a low coupling coefficient.

[0057] In the power distribution box, mechanical contact switches and MOSFET solid switches are configured as multiple ones according to the requirements, and each independently constitutes a power distribution circuit and is electrically connected to the output connector so as to be connected to the load to realize effective power distribution.

[0058] During power distribution: the power supply is connected to the distribution box, converted into the target voltage by the voltage conversion module, and connected to the bus bar to directly supply power to the load.

[0059] When a mechanical contact switch is required for power distribution, the safety switch is disconnected, transistor Q1 is turned off, and the voltage on the busbar is distributed to relay J2 through relay J1; the control signal on the gate of transistor Q2 is valid, making transistor Q2 conductive, and there is an output at the contact of relay J2. This output is an output of the distribution box, which is connected to the corresponding pin of the output connector to provide the required voltage for the load electrically connected to the pin, completing the power distribution; it is connected to distribute power to the load. Only when the safety switch is not turned on and the control signal is a valid signal, can power distribution be achieved through the mechanical contact switch, ensuring the correctness of power distribution.

[0060] When MOSFET solid-state switch is required for power distribution, the voltage on the bus bar is connected to the optocoupler and the effective control signal. The optocoupler is turned on under the control signal and the voltage is connected to the gate of MOS tube Q4 as the gate bias to turn on MOS tube Q4. The power supply connected to the drain of MOS tube Q4 is used to distribute power to the load.

[0061] The power supply on the drain of the MOS tube Q4 can be provided by a bus bar, and the drain is connected to the bus bar; it can also be provided by a relay J1. The relay J1 is configured as a double-group contact relay, one group of contacts is used to provide power to the relay J2, and completes power distribution when the J2 coil is energized; one group of contacts is used to provide power to the MOS tube Q4, connected to its drain, and completes power distribution when it is turned on.

[0062] When the power supply on the drain of MOS tube Q4 is provided by relay J1, the safety switch must not be turned on and the control signal must be a valid signal before power distribution can be achieved through the MOS EFT solid-state switch, which also ensures the correctness of power distribution.

[0063] When there is no need for mechanical contact switch power distribution, the safety switch is turned on, the transistor Q1 is turned on, and the normally open contact of the relay J1 is closed, forming a suspended state; the normally closed contact is disconnected, cutting off the bus power supply access. At this time, even if the control signal connected to the gate of the transistor Q2 is valid and the relay J2 coil is energized, there is no power access to the contacts of the relay J2 at this time, and no power can be used to distribute to the load, effectively cutting off the power distribution.

[0064] Alternatively, the safety switch is disconnected, the transistor Q1 is cut off, the control signal on the gate of the transistor Q2 is an invalid signal, the transistor Q2 is cut off, the relay J2 is disconnected, and the power distribution is cut off; this method is to control the cut-off of the transistor Q2 to cut off the power to the relay J2 coil, and the relay J2 is disconnected to achieve no power distribution.

[0065] Alternatively, the safety switch is turned on, the transistor Q1 is turned on, the relay J1 is actuated, and at the same time, the control signal on the gate of the transistor Q2 is an invalid signal, the transistor Q2 is turned off, the relay J2 is disconnected, and the power distribution is cut off. The safety switch and the control signal act simultaneously to achieve rapid power off.

[0066] When there is no need for MOSFET solid switch power distribution, the control signal connected to the optocoupler is a failure signal, which turns off the optocoupler, MOS tube Q4, and cuts off the power distribution to achieve independent power-off control; when the power on the drain of MOS tube Q4 is provided by relay J1, it can also be unified for power-off control, the safety switch is turned on, the transistor Q1 is turned on, and the normally open contact of relay J1 is closed, forming a suspended state; the normally closed contact is disconnected, and the busbar power supply is cut off. At this time, even if the control signal connected to the optocoupler is valid and MOS tube Q4 is turned on, there is no power connection to the drain of MOS tube Q4 at this time, and no power can be used to distribute to the load, effectively cutting off the power distribution; at the same time, the power distribution of relay J2 is also cut off. When the safety switch is invalid in conjunction with the control on the optocoupler, the MOSFET solid switch is quickly turned off.

[0067] When busbar power distribution or distribution box power distribution is not required, cut off the power supply to the distribution box.

[0068] Combination Figure 5 The connection relationship of the mechanical contact switch transistor Q1, transistor Q2, relay J1, relay J2, and safety switch disclosed in the present invention is: the emitter of the transistor Q1 is used for bias signal access, and the collector is grounded through the relay J1 coil; one end of the contact of the relay J1 is connected to the bus bar, and the other end is connected to one end of the contact of the relay J2, and the other end of the contact of the relay J2 is used as a load connection end and is connected to the output connector; the coil of the relay J2 is connected in series between the collector of the transistor Q2 and the ground, and the emitter of the transistor Q2 is used for bias signal access; the safety switch is used to connect the ground and the gate of the transistor Q1, and a short-circuit pin can be used. When the short-circuit pin shorts the gate of the transistor Q1 and the ground, the transistor Q1 is cut off, and the entire switch cannot distribute power; the gate of the transistor Q2 is used for control signal access. When the access signal is invalid, the transistor Q2 is cut off, and the entire switch cannot distribute power. The switch can distribute power correctly and effectively only when the safety switch does not short-circuit the gate of transistor Q1 and the control signal connected to the gate of transistor Q2 is valid. This control mode is ground / open control, that is, it is effective when the control end is grounded and invalid when the control end is left open, which improves the reliability of the distribution box.

[0069] It should be understood by those skilled in the art that Figure 5 Although the circuit structure shown is composed of PNP transistors, it can also be composed of NPN transistors. The control mode is: it is effective when the control terminal is connected to the power supply and it is invalid when the control terminal is grounded.

[0070] Another type of the mechanical contact switch is further configured with a diode D1, a diode D2, a diode D3, a diode D4, a resistor R1, a resistor R2, a resistor R3, and a resistor R4 on the basis of the above structure. The base of the transistor Q1 is connected to the anode of the diode D1 via the resistor R1, and is connected to the emitter of the transistor Q1 via the resistor R2. R1 and R2 constitute a fast conduction circuit of the transistor Q1; the cathode of the diode D1 is connected to the anode of the diode D2 and is grounded, the cathode of the diode D2 is connected to the collector of the transistor Q1, and is grounded via the coil of the relay J1, forming a structure connected in parallel with the coil of the relay J1; the cathode of the diode D1 and the anode of the diode D2 serve as safety switch connection terminals.

[0071] In the power distribution state, diodes D1 and D2 prevent external interference signals input into the distribution box through the distribution box connector from flowing back into the control loop used to generate the control signal and causing circuit damage; in the power-off process, the safety switch short-circuits the gate of transistor Q1 and the ground, diodes D1 and D2 are turned on, quickly lowering the base and collector voltages of transistor Q1, and transistor Q1 is quickly turned off.

[0072] The base of transistor Q2 is connected to the anode of diode D3 through resistor R3, and connected to the emitter of transistor Q2 through resistor R4; the cathode of diode D3 is used as the access terminal of control signal; the collector of transistor Q2 is connected to the cathode of diode D4, and grounded through the coil of relay J2, and the anode of diode D4 is grounded, forming a structure connected in parallel with the coil of relay J2. The functions of resistors R3 and R4 and the functions of diodes D3 and D4 are the same as those of resistors R1 and R2 and diodes D3 and D4, and will not be repeated here.

[0073] Combination Figure 6The MOS EFT solid-state switch disclosed in the present invention is further configured with capacitors and resistors C1, C2, resistors R5-R9, diodes D5-D7, voltage-stabilizing diode Z3 and transistor Q3 on the basis of including MOS tube Q4 and optocoupler; the power supply is filtered by capacitor C1 and then connected to the control end of the optocoupler through resistor R5, and resistor R6 is connected in parallel to both ends of resistor R5; the control end of the optocoupler is also connected to the anode of diode D5 through C2, and the cathode of D5 is used for control signal access; when the control signal is valid, the output of the optocoupler is connected to the gate of MOS tube Q4 through diode D6 and resistor R8; the output of the optocoupler is also divided into two paths, one is connected to the output-end of the optocoupler and the source of MOS tube Q4 through resistor R7, and the other is connected to the base of transistor Q3; the emitter of transistor Q3 is connected to the cathode of D6, and the collector is connected to the output-end of the optocoupler and the source of MOS tube Q4; the anode of voltage-stabilizing diode Z3 is connected to the collector of transistor Q3, and the cathode of Z3 is connected to the cathode of D6. When the ground / open control signal is grounded (effective on command), the 28V voltage enters the primary side +control of the photovoltaic device IC1 through the current limiting R5 and R6 and returns to the ground -control through the diode D5. The light-emitting diode of the primary side inside the photovoltaic device IC1 emits light, and a voltage of about 13V is generated between the secondary side +out and -out pins to drive the N-type MOS tube Q4 to turn on. The Z3 voltage stabilizing diode plays a protective role to prevent the gate-source voltage of the MOS tube from being too large and breaking down; the transistor Q3 and the resistor R7 constitute the gate charge discharge path of the MOS tube, and provide a gate voltage discharge circuit when the IC1 front-stage shutdown control signal is valid (the control end is floating), thereby increasing the MOS shutdown speed and reducing the switching loss. The role of D6 is to ensure that when the MOS tube is turned on, the VBE of Q3 provides a positive bias voltage to ensure that the transistor is cut off, and when the MOS is turned off, the VBE provides a reverse bias voltage to ensure that the transistor is saturated and turned on.

[0074] The power distribution box is also configured to include a voltage sampling circuit for collecting the voltage on the bus bar. The circuit structure of the voltage sampling circuit is as follows: Figure 7 As shown, it mainly includes a precision linear optocoupler and an amplifier. The output of the precision linear optocoupler is connected to the in-phase input terminal and the reverse input terminal of the amplifier through resistors R13 and R14 respectively, and the amplifier outputs the sampling result; a resistor R16 and a capacitor C10 are respectively connected in series between the reverse input terminal and the output terminal of the amplifier.

[0075] The voltage sampling circuit can adjust the amplification factor by simply adjusting the ratio of R14 and R16, Vout = (R39 / R37)*(V out+ -V out- ) not only achieves electrical isolation but also reduces volume and weight, and has a higher cost-effectiveness than Hall sensors. To ensure the accuracy of voltage sampling, the resistance values ​​of R10, R11, R13~R16 should have high accuracy, and the input optocoupler V INThe voltage at the end is around 2V to ensure data collection and calculation accuracy.

[0076] Figure 7 In the figure, the 100V voltage connected to the resistor R10 is only an exemplary voltage, indicating that the voltage on the bus bar being collected is 100V. It is a principle example of outputting a 100V voltage after being processed by a precision linear optocoupler and an amplifier, and is not a limitation on the voltage sampling circuit.

[0077] The power distribution box is also configured to include a current sampling circuit for collecting current on the bus bar. The current sampling circuit includes a Hall sensor with a reverse connection at the current input end. The specific circuit structure is as follows: Figure 8 As shown, the Hall sensor outputs the sampling result. Figure 8 The 100V shown in the figure is only an exemplary voltage corresponding to the current, indicating that the voltage corresponding to the current on the collected bus bar is 100V, and it is a principle example of outputting I_100V after passing through the Hall sensor, and is not a limitation on the current sampling circuit.

[0078] The outputs of the voltage acquisition circuit and the current acquisition circuit in the distribution box are respectively connected to the output connector of the distribution box, and are transmitted to the external control circuit through the output connector. They can be used as required, such as as a basis for monitoring the working status of the distribution box, whether a fault occurs, whether there is load, etc., and as an auxiliary monitoring basis.

[0079] In order to prevent the sampled output voltage from exceeding the port withstand voltage of 3.3V of the microcontroller processor in the external control loop, the current input end of the Hall sensor of this current sampling circuit is reversely connected to ensure that the sampled voltage output of the sensor is no more than 2.5V, which can effectively protect the microcontroller port without the need for a port protector.

[0080] In addition, this distribution box provides an external auxiliary power supply interface for easy use during ground debugging. The external power supply is separated by a diode and then fed into the main battery 28V bus.

[0081] Combination Figure 1-4 , solder the electronic components 9, voltage conversion module (to realize DC-DC conversion) 10, relay 11, input connector 5, output connector 6, etc. on the printed circuit board to construct a functional circuit; then install the printed circuit board 2 on the heat dissipation base plate 11 through the support column 3 and the screw assembly 4; or install the printed circuit board 2 on the heat dissipation base plate 11 through the screw assembly 4, install the cover plate 14, and then install the corner connector 8 at the corresponding positions of the heat dissipation base plate and the cover plate, and finally assemble the left side plate, the right side plate, the front panel, and the rear panel, and lock them tightly with the countersunk screws 7.

[0082] This distribution box can be configured to distribute power to any equipment / device that requires power distribution, such as distributing power to drones. The distribution box is matched with the drone central control system. The drone central control system generates a control signal and connects to the distribution box to control the conduction and cutoff of the optocoupler and transistor Q2 to achieve power distribution.

[0083] Figure 9 shows the connection relationship between the power distribution box and the relevant loads on the drone when it is used for power distribution of the drone. In the figure, K1 represents a mechanical contact switch and K2 represents a MOSSEFT solid switch.

[0084] In the power distribution state for the drone, the drone power supply is connected to the distribution box, which converts the connected power supply voltage into the target voltage through the voltage conversion module and connects it to the bus bar respectively; the power-demanding load is connected to the output connection of the distribution box to realize direct power distribution through the bus bar, power distribution through K1, and power distribution through K2. Fig. 9 As shown, the UAV load YX, switch, ad hoc network, high-precision inertial navigation, left / right aileron, left / right tail rudder, etc. are directly powered by the bus; mission payload equipment, fuse, pyrotechnics, insurance control switches, etc. are powered by K1; and the load servo is powered by K2.

[0085] When this power distribution box is used for power distribution of UAV, the safety switch A and the safety switch B are short-circuited by the safety pin during ground debugging, the base of transistor Q7 is in a low level state, and a control current flows between the E pole and the B pole of Q7. Q7 is turned on, the coil of relay J1 is energized, and the normally closed contact of the relay is disconnected. The 28V_BAR and 8.5V_BAR power supplies cannot be distributed to the lower-level circuits. Regardless of whether the lower-level channel control signals (such as mission payload control 3 and payload servo 2 control) are valid, the corresponding channel outputs (such as mission payload equipment) are 3, load servo 2 power supply) cannot distribute power output; only after the aircraft takes off the ground, after the safety switch A and the safety switch B are disconnected, the transistor Q7 is turned off, the relay J1 coil loses power, and the normally closed contact of the relay J1 is restored to the on state. At this time, the lower-level channel control signal (such as mission load control 3, load servo 2 control) is valid when it is low level, and the electromagnetic relay J1 or field effect tube Q4 of the corresponding channel output (such as mission load equipment 3, load servo 2 power supply) is turned on, and the corresponding power supply can be output to the corresponding channel. Since the safety switch and channel control signals both use ground / open signals, that is, they are valid when the control end is grounded, and invalid when the control end is open, and an anti-reverse diode is added to the control pole to prevent external interference signals from flowing into the control loop in reverse to cause circuit damage or product malfunction, the circuit design has high reliability.

[0086] The sampling results of the voltage sampling circuit and current sampling current in the distribution box can be input into the UAV central control system to realize the monitoring of the distribution box.

[0087] The bottom plate of this power distribution box is a heat dissipation bottom plate. Figure 3 The figure shows a fence-type heat dissipation tooth structure. When the power distribution box is used in a drone, the heat dissipation tooth groove direction is along the flight direction of the drone, and the power distribution box is installed under the drone fuselage. The heat dissipation tooth-shaped metal bottom plate along the wind direction can efficiently perform air cooling and heat dissipation during the flight of the drone.

[0088] The power distribution box is configured with a voltage conversion module as required, so that the voltage application range of the power distribution box is wider and can meet the battery power distribution use of 43V~160VDC.

[0089] This power distribution box is small in size and light in weight. When meeting the power distribution requirements of 600W, its size is only 214mm×177mm×39mm and its weight is 1.5kg.

[0090] Power distribution as described in this article refers to providing the required power to the loads that require it.

[0091] This distribution box has a strong ability to resist external interference. On the one hand, the anti-interference is the electrical isolation between different voltage systems, and on the other hand, different circuit structures are selected according to different load characteristics. For example, for load channels with strict power consumption requirements and leakage current sensitivity, electromagnetic relay type switches are used, while for load channels with higher instantaneous overload capacity requirements, MOSFET solid-state switches are used; furthermore, the control command adopts a ground / open signal and limits the current direction through a diode (generally the interference is a positive pulse, and the ground / open control command can prevent malfunction caused by positive pulse interference), and the control signal is amplified by a transistor to drive the relay (attached Figure 5 ), by adjusting the resistance values ​​of R3 and R4, the transistor Q2 can work reliably in the cutoff region when the base signal is open (Note: in some cases, the open-circuit impedance to ground in the user's ground / open command is not infinite but an equivalent impedance of tens of kΩ to hundreds of kΩ), and can work reliably in the saturation region when the base signal of the transistor Q2 is at a low level. For example, in the technical solution, R4 takes a value of 470Ω and R3 takes a value of 4.7kΩ. When the user's ground / open command is open, the equivalent impedance to ground is 50kΩ, and the VBE of transistor Q2 is 470Ω / (470Ω+4700Ω+50000Ω)*(28V-0.7V)=0.233V<0.6V. The transistor Q2 can be reliably cut off; when the control signal is grounded, Q2's VBE=470Ω / (470Ω+4700Ω)*(28V-0.7V)=2.48V>0.6V and the base current Ib=2.48V / 4.7kΩ=0.527mA, Ic=β*Ib=100*0.527=52.7mA is much larger than the current 10mA required by the relay coil, the transistor is saturated and turned on, and the relay can operate reliably; when the ground / open control signal is open, Fig.10 shown.

[0092] The present disclosure has been described by the above-mentioned relevant embodiments, but the above-mentioned embodiments are only examples for implementing the present disclosure. It must be pointed out that the disclosed embodiments do not limit the scope of the present disclosure. On the contrary, changes and modifications made without departing from the spirit and scope of the present disclosure are all within the scope of patent protection of the present disclosure.

Claims

1. A hybrid distribution box, characterized in that: The distribution box is configured to include: The mechanical contact switch, as a control switch for distributing power to the power distribution channel where the fuse and the explosive device are located, is configured to include a safety switch, a transistor Q1, a relay J1, a transistor Q2 and a relay J2; The MOSFET solid-state switch, as a control switch for distributing power to a distribution channel with fast response time, small load current, high overvoltage requirement, and low on-resistance, is configured to include an optocoupler and a MOS tube Q4; A voltage conversion module for providing multiple voltages; The bus bar is outputted from the voltage conversion module, and different voltage bus bars are formed according to different voltages outputted from the voltage conversion module; When distributing power to the load, the load is directly connected to the bus bar, connected to the bus bar through a mechanical contact switch, or connected to the bus bar through a MOSFET solid switch; the power supply is connected to the distribution box, converted into a target voltage by a voltage conversion module, and connected to the bus bar to directly supply power to the load; the fuse is disconnected, the transistor Q1 is cut off, and the voltage on the bus bar is distributed to the relay J2 through the relay J1; the control signal on the gate of the transistor Q2 turns on the transistor Q2, and the relay J2 is turned on to distribute power to the load; the voltage on the bus bar is connected to the optocoupler, which is turned on under the action of the control signal and connects the voltage to the gate of the MOS tube Q4 as a gate bias to turn on the MOS tube Q4, and the voltage connected to the drain of the MOS tube Q4 is used for load distribution; When power distribution is not required with a mechanical contact switch, the safety switch is turned on, the transistor Q1 is turned on, the relay J1 is actuated, and the power distribution is cut off; or, the safety switch is turned off, the transistor Q1 is turned off, the control signal on the gate of the transistor Q2 is an invalid signal, the transistor Q2 is turned off, the relay J2 is turned off, and the power distribution is cut off; or, the safety switch is turned on, the transistor Q1 is turned on, the relay J1 is actuated, and at the same time, the control signal on the gate of the transistor Q2 is an invalid signal, the transistor Q2 is turned off, the relay J2 is turned off, and the power distribution is cut off; When there is no need for MOSFET solid-state switch power distribution, the control signal controls the optocoupler to cut off, the MOS tube Q4 to cut off, and the power distribution is cut off; When busbar power distribution or distribution box power distribution is not required, cut off the power supply to the distribution box.

2. The hybrid distribution box according to claim 1, characterized in that: The voltage on the bus bar is also distributed to the drain of the MOS tube Q4 after passing through the relay J1. When the MOSFET solid-state switch is not needed for power distribution, the safety switch is turned on, the transistor Q1 is turned on, and the relay J1 is actuated to cut off the power distribution to the MOS tube Q4, thereby cutting off the power distribution; or, the control signal on the optocoupler is invalid, so that the optocoupler is cut off, and at the same time the safety switch is turned on, the transistor Q1 is turned on, and the relay J1 is actuated to cut off the power distribution to the MOS tube Q4, thereby cutting off the power distribution.

3. The hybrid distribution box according to claim 1, characterized in that: The voltage on the bus bar is distributed to the load after passing through relay J1. When relay J1 is no longer needed to distribute power to the load, the safety switch is turned on, transistor Q1 is turned on, relay J1 is activated, and power distribution is cut off.

4. The hybrid distribution box according to claim 1, characterized in that: The base of transistor Q1 is connected to the anode of diode D1 via resistor R1, and is connected to the emitter of transistor Q1 via resistor R2; the cathode of diode D1 is connected to the anode of diode D2 and is grounded, the cathode of diode D2 is connected to the collector of transistor Q1, and is grounded via the coil of relay J1, forming a structure connected in parallel with the coil of relay J1; the cathode of diode D1 and the anode of diode D2 serve as the safety switch connection terminals.

5. The hybrid distribution box according to claim 1, characterized in that: The base of transistor Q2 is connected to the anode of diode D3 via resistor R3, and is connected to the emitter of transistor Q2 via resistor R4; the cathode of diode D3 serves as the access terminal of control signal; the collector of transistor Q2 is connected to the cathode of diode D4, and is grounded via the coil of relay J2, and the anode of diode D4 is grounded, forming a structure connected in parallel with the coil of relay J2.

6. The hybrid distribution box according to claim 1, characterized in that: The optocoupler output is connected to the gate of the MOS tube Q4 through the diode D6 and the resistor R7. The optocoupler output is also connected to the base of the transistor Q12. The emitter of the transistor Q12 is connected to the cathode of the diode D6, and the collector is connected to the optocoupler output - and the source of the MOS tube Q4, and is grounded through the resistor R8; the other end of the resistor R8 is connected to the anode of the Zener diode Z3, and the cathode of the Zener diode Z3 is connected to one end of the resistor R7 connected to the cathode of the diode D6; the ground end of the resistor R8 is also connected to the anode of the diode D7, and the cathode of the diode D7 is connected to the source of the MOS tube Q4.

7. The hybrid distribution box according to claim 6, characterized in that: The power supplied to the control end of the optocoupler is filtered and connected through resistor R5, and resistor R6 is connected in parallel at both ends of resistor R5. The control end of the optocoupler is also connected to the anode of diode D5 through capacitor C2, and the cathode of diode D5 is used for control signal access.

8. The hybrid distribution box according to claim 1, characterized in that: The distribution box is also configured with a voltage sampling circuit for collecting the voltage on the bus bar, and the voltage sampling circuit includes a precision linear optocoupler and an amplifier. The output of the precision linear optocoupler is connected to the in-phase input terminal and the reverse input terminal of the amplifier via resistors R13 and R14, respectively, and the amplifier outputs the sampling result; a resistor R15 and a capacitor C9 are respectively connected in series between the reverse input terminal and the output terminal of the amplifier.

9. The hybrid distribution box according to claim 7, characterized in that: The precision linear optocoupler V IN The voltage at the end is between 1.5V and 2.5V.

10. The hybrid distribution box according to claim 7, characterized in that: The V supplied to the precision linear optocoupler IN The power supply at the end is connected after being divided by resistors R11 and R10; the amplifier's in-phase input end is also grounded via resistor R16.

11. The hybrid distribution box according to claim 1, characterized in that: The power distribution box is also configured with a current sampling circuit for collecting current on the bus bar. The current sampling circuit includes a Hall sensor with a reversely connected current input terminal, and the Hall sensor outputs a sampling result.

12. The hybrid distribution box according to claim 1, characterized in that: The power distribution box comprises a housing and a printed circuit board assembled in the housing, the bottom plate of the housing is a heat dissipation bottom plate, and the printed circuit board is assembled with the heat dissipation bottom plate through a support column and a screw assembly; The mechanical contact switch, MOSFET solid switch, voltage conversion module, and bus bar are arranged on the printed circuit board. The housing is equipped with an input connector and an output connector. The power supply is connected to the voltage conversion module via the input connector. The mechanical contact switch, MOSFET solid switch, and bus bar are electrically connected to the output connector respectively. The output connector serves as a connection port connected to the load.

13. The hybrid distribution box according to claim 11, characterized in that: The heat dissipation bottom plate is a fence-type heat dissipation tooth structure.

14. The hybrid distribution box according to claim 12, characterized in that: The power distribution box is used in drones, and the heat dissipation groove direction is along the flight direction of the drone.

15. A UAV power distribution system, characterized in that: The system includes a UAV central control system and a distribution box. The UAV central control system generates a control signal connected to the distribution box to control the conduction and cutoff of the optocoupler and the transistor Q2. The distribution box distributes power to the power-requiring loads on the UAV. The distribution box is the distribution box described in any one of claims 1 to 14.

Images