An electric helicopter electrical system and a control method thereof

Abstract

The application provides an electric helicopter electrical system, comprising an electric power system, an intelligent control system, a water cooling system and a low-voltage power distribution system; the electric power system comprises a power battery, a high-voltage box, a controller and a motor, provides a power source for the whole machine, and transmits the power to the rotor by a transmission system to provide the lift for the helicopter; the water cooling system is divided into: the power battery water cooling system comprises a large water pump, a large water pump controller and a power battery heat exchanger; the motor water cooling system comprises a small water pump, a small water pump controller, a controller heat exchanger, an overflow water tank, an expansion water tank and a radiator; the intelligent control system is composed of a comprehensive management computer and a rotor speed monitor; the low-voltage power distribution system comprises a 24V storage battery and on-board low-voltage electrical equipment; meanwhile, the application provides an electric helicopter electrical system control method.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aviation electrical systems, and particularly relates to an electric helicopter electrical system and a control method thereof. BACKGROUND

[0002] An all-electric helicopter is a new configuration helicopter driven completely by electric energy. In the development process of the aviation field, the all-electric helicopter is an important index of the fifth generation helicopter. Electric energy replaces the traditional hydraulic, transmission, and oil secondary energy, which means higher transmission efficiency, more integrated control logic, and faster response control capability. In particular, electric energy as the main energy source of the helicopter has great significance for environmental protection and green aviation. SUMMARY

[0003] The application aims to provide an electric helicopter electrical system composed of a power battery, a high-voltage box, a motor controller, a motor, a 24V storage battery, a comprehensive management computer, a water-cooling pump, a water-cooled motor, an expansion water tank, a radiator, and other devices, which takes electric energy as the main energy source.

[0004] In a first aspect, the application provides an electric helicopter electrical system, which comprises an electric power system, an intelligent control system, a water-cooling system, and a low-voltage power distribution system.

[0005] The electric power system comprises a power battery, a high-voltage box, a controller, and a motor, which provides a power source for the whole machine and transmits the power to the rotor through a transmission system to provide lift for the helicopter.

[0006] The water-cooling system comprises a power battery water-cooling system including a large water pump, a large water pump controller, and a power battery heat exchanger, and a motor water-cooling system including a small water pump, a small water pump controller, a controller heat exchanger, an overflow water tank, an expansion water tank, and a radiator.

[0007] The intelligent control system is composed of a comprehensive management computer and a rotor speed monitor.

[0008] Preferably, the low-voltage power distribution system comprises a 24V storage battery and on-board low-voltage electrical equipment.

[0009] Preferably, the power battery is internally composed of four batteries connected in series, and each battery is composed of a plurality of small batteries connected in series. Each battery is externally linked with a contactor and a diode. When a battery fails, a BMS sends a shutdown instruction to short-circuit the failed battery, and the whole machine is powered by the remaining three power batteries. The power supply total positive is connected with the high-voltage box, and the total negative is connected with the controller, which provides a high-voltage power source for the whole machine.

[0010] Preferably, the power battery internal BMS management module collects the capacity, voltage, current and temperature information of each power battery, judges the power quality and reports the information to the comprehensive management computer and displays it on the control screen, and the power battery connection instruction is given and sent through the comprehensive management computer.

[0011] Preferably, the large and small water pumps are power equipment for providing circulating cooling water to the power battery and the motor, and the large and small water pump controllers collect the water pump cooling water flow rate and provide power to the water pump, and at the same time feed back the collected flow rate to the comprehensive management computer, and receive the instruction of the comprehensive management computer to control the water pump flow rate.

[0012] The controller heat exchanger, radiator and expansion tank dissipate the heat of the cooling water discharged from the equipment by the water pump, and the cooled cooling water is transmitted to the controller and the motor by the large and small water pumps to cool the equipment.

[0013] Preferably, the rotor speed controller collects the rotor speed and reports it to the comprehensive management computer, the comprehensive management computer compares the rotor speed with the motor speed, combines the motor working efficiency, and uses the rotor speed control signal as a reference and corrects the rotor speed control signal.

[0014] The main function of the comprehensive management computer is to control the whole machine system equipment, transmit the collected voltage, current, frequency, speed and other physical quantities to the comprehensive management computer, and monitor the physical quantities by the comprehensive management computer, and issue control instructions to the equipment.

[0015] Preferably, the comprehensive management computer also has power distribution function, which is mainly based on the input voltage of the busbar, controls the power supply of the equipment through the internal control board and protection devices, monitors the current, uses the Irat curve as the protection basis, and implements the overcurrent and short circuit protection function for the equipment.

[0016] Preferably, the on-board low-voltage electrical equipment adopts the single-wire system in traditional aviation, and according to the importance of equipment power supply, the emergency equipment is set to two-way power distribution, and the two-way power distribution is realized by two independent busbars with 24V storage battery providing power, one of which provides power through busbar 1 to the comprehensive management computer, motor controller and power battery BMS module, and finally connects to the machine ground to complete the first power distribution, and this process is protected by using circuit breakers, and the other one is provided by the comprehensive management computer, and the equipment power is supplied through a busbar in the comprehensive management computer and named as busbar 2, and then the control circuit and power are switched and adjusted by the internal solid-state power controller of the comprehensive management computer to supply power to the load, and the load negative end is also connected to the machine ground to form a loop.

[0017] In a second aspect, the application also provides an electric helicopter electrical system control method, the method comprising:

[0018] Step 1, turn on the 24V battery, the integrated management computer and the busbar 2 are automatically connected, the operator sequentially connects the power battery, the motor controller and the rotor speed controller through the integrated management computer, the BMS module collects, judges the single battery voltage, current and battery temperature information of the power battery and reports them to the integrated management computer;

[0019] Step 2, when the BMS module collects that the single battery has problems such as over-temperature and over-current which seriously damage the battery, the BMS module will cut off the abnormal single battery by connecting the short-circuit current of the abnormal single battery and report the alarm information and the battery abnormal cutting information to the integrated management computer;

[0020] Step 3, after the single battery is cut off, the remaining three power batteries continue to work, if the single battery again has serious alarm signals such as over-temperature and over-current, the BMS module will not cut off the abnormal single battery, but will report this part of the content to the integrated management computer;

[0021] Step 4, after the power battery and the motor controller are connected, the motor controller converts the direct current of the power battery into alternating current to drive the motor to rotate and in turn drive the rotor to rotate, the motor controller collects the motor speed, temperature, voltage, current and other information and reports them to the integrated management computer, the integrated management computer judges the information uploaded by the rotor speed controller and corrects the motor speed control instruction;

[0022] Step 5, the integrated management computer will cool the power battery or the motor according to the preset temperature threshold by connecting the water cooling system according to the lowest temperature of the single battery reported by the battery and the motor temperature;

[0023] Step 6, the high-voltage power part on the machine, the high-voltage part adopts a double-wire circuit loop, the voltage output by the positive terminal of the power battery is transmitted to the motor controller through the high-voltage box composed of contactors and fuses, the built-in DC / AC converter of the motor controller converts the direct current output by the power battery into three-phase alternating current required by the motor to drive the motor to rotate, the motor drives the rotor to rotate through the transmission part on the machine to provide lift for the helicopter and in turn realize flight;

[0024] Step 7, the low-voltage power distribution system on the machine is composed of two busbars 1 and 2 which are powered by 24V batteries and independent of each other, the busbar 1 directly distributes power to key electrical equipment and increases different specifications of circuit breakers on the feeder circuit of the power distribution, the busbar 2 is built in the integrated management computer and realizes over-current and short-circuit protection functions through the SSPC power distribution circuit, the negative end of the electrical equipment adopts the single-wire system of the traditional aviation system and is connected to the machine ground to form a loop.

[0025] The beneficial technical effects of the present application are:

[0026] 1. The power battery adopts a form of four batteries in series, and each battery is connected with a short circuit loop, so that when any battery fails, it can be quickly cut off, but the remaining three batteries can continue to power the whole machine. It can improve the reliability and safety of the whole system, and reduce the power supply network of the whole system due to single point failure, abnormal single device.

[0027] The preferred short circuit loop is composed of a contactor and a diode. When a single battery over-temperature or abnormally damaged, the short circuit circuit is turned on, but since the short circuit loop has a diode, it can short circuit the single battery in the whole electrical system, and avoid the single battery and the short circuit loop forming a loop.

[0028] 2. In order to reduce the influence of power battery temperature rise, an integrated water cooling system is integrated, and different flow rates of cooling water are used for cooling according to the different temperature rises of power battery and motor. Compared with the traditional on-board environmental control system, two different water cooling systems can change the flow rate of cooling water according to the temperature change of the water cooling equipment at any time. It can avoid energy waste and improve cooling efficiency.

[0029] 3. The highly integrated on-board control system combines energy distribution. Compared with the traditional aircraft with multiple computers and the system of separate control and power distribution, it can better improve the capacity utilization, improve the transmission efficiency of control signals, avoid multiple storage and transmission of signals, and reduce unnecessary waste.

[0030] 4. The high and low voltage systems are separated, the high voltage adopts double line system, and the low voltage adopts traditional single line system, which can reduce weight, reduce consumption of power energy of high voltage system, increase energy reserve required for flight, and improve the reliability of the whole system.

[0031] 5. The rotor speed is compared with the motor speed for reference, which can strengthen the correction of motor speed control and reduce the misjudgment of speed. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a kind of electrical system principle schematic diagram suitable for electric helicopter provided by the embodiment of the present application. DETAILED DESCRIPTION

[0033] The application selects a single motor system drive, improves the reliability of the whole system, increases a water cooling system, improves the battery cooling and heat dissipation capacity, effectively suppresses the battery temperature rise problem, adopts high and low voltage isolation, the high voltage power part adopts double wire system, improves the safety of the system, at the same time, the low voltage electrical equipment adopts the single wire system in the traditional aviation field, separates the high and low voltage, effectively solves the electromagnetic interference problem and reduces the consumption of high voltage power battery capacity, uses a highly integrated comprehensive management computer, abolishes the state of the traditional helicopter multiple computers, and uses the highly integrated computer, improves the control efficiency.

[0034] Please refer to Figure 1 The electrical system of the helicopter provided by the application is composed of an electric power system, an intelligent control system, a water cooling system and a low voltage power distribution system.

[0035] The electric power system includes power batteries, a high voltage box, a controller and a motor and the like, provides power supply for the whole machine, and transmits the capacity to the rotor by a transmission system to provide lift for the helicopter.

[0036] The power battery is internally connected by four batteries in series, each battery is connected by a plurality of small batteries in series, and each battery is externally connected with a contactor and a diode. When a battery fails, the BMS sends a shutdown instruction to short-circuit the failed battery, and the whole machine is powered by the remaining three power batteries. The power supply total positive is connected with the high voltage box, and the total negative is connected with the controller, to provide high voltage power source for the whole machine.

[0037] The internal BMS management module of the power battery collects the capacity, voltage, current, temperature and the like of each power battery, judges the power quality, and reports the information to the comprehensive management computer and displays it on the control screen. The power battery connection instruction is given, and is sent through the comprehensive management computer.

[0038] The high voltage box is internally connected by a contactor and a fuse in series, connected with the power battery total positive, and connected with the controller at the other end. In the case of power battery short circuit and single battery disconnection without response, the power supply line is disconnected, the power battery is disconnected, and the power battery is protected.

[0039] The motor controller receives direct current from the power battery, the motor controller is built-in a DC / AC converter, converts the direct current of the power battery into alternating current, outputs to the motor, drives the motor to work, collects the motor speed, temperature, voltage and current value, feeds back the collected data to the comprehensive management computer, and receives the instruction of the comprehensive management computer to control the motor speed, connection and the like.

[0040] The motor receives three-phase AC power from the controller to drive the motor to rotate, and drives the rotor to rotate through the transmission system. It works according to the control instructions from the controller and is protected.

[0041] II. The water cooling system is mainly composed of: power battery water cooling system including large water pump, large water pump controller, power battery heat exchanger and other equipment, motor water cooling system including small water pump, small water pump controller, controller heat exchanger and other equipment, overflow tank, expansion tank and radiator.

[0042] The large and small water pumps are power equipment that provide circulating cooling water to the power battery and the motor. The large and small water pump controllers collect the flow rate of the water pump cooling water, provide power to the water pump, and feed back the collected flow rate to the comprehensive management computer, and receive instructions from the comprehensive management computer to control the water pump flow rate.

[0043] The controller heat exchanger, radiator and expansion tank dissipate the heat of the cooling water discharged from the equipment, and the cooled cooling water is transmitted to the controller and motor through the large and small water pumps to cool the equipment.

[0044] III. The intelligent control system is mainly composed of a comprehensive management computer, a rotor speed monitor and other equipment,

[0045] The rotor speed controller collects the rotor speed and reports it to the comprehensive management computer. The comprehensive management computer compares the rotor speed with the motor speed, and combines the motor efficiency and the rotor speed control signal as a reference, and corrects the rotor speed control signal.

[0046] The main function of the comprehensive management computer is to control the system equipment. The collected physical quantities such as voltage, current, frequency and speed are transmitted to the comprehensive management computer, and the physical quantities are monitored by the comprehensive management computer, and the equipment issues control instructions;

[0047] The comprehensive management computer also has power distribution function, mainly based on busbar input voltage, through internal control board and protection devices to control the distribution of current to the equipment, and monitor the current, based on the I rat curve protection, to implement overcurrent and short circuit protection functions for the equipment.

[0048] Four, the low-voltage power distribution system on the machine includes 24V battery, integrated management computer and low-voltage electrical equipment on the machine, etc. The low-voltage electrical equipment on the machine adopts the single-wire system in traditional aviation, and according to the importance of the power supply of the equipment, the emergency equipment is set to two power distribution, and the two power distribution is realized by two independent bus bars which are provided with 24V battery power, one of which is provided with 24V battery power, and the other is provided with 24V battery power. The bus bar 1 is connected to the integrated management computer, the motor controller and other equipment, and finally connected to the machine ground to complete the first power distribution. This process uses the form of circuit breaker for protection. The other is provided by the integrated management computer, and the power of the equipment is connected to the bus bar in the integrated management computer and named as bus bar 2. Then the power is switched and adjusted by the solid-state power controller in the integrated management computer to supply power to the load of the electrical equipment. The load negative terminal is also connected to the machine ground to form a loop.

[0049] It should be noted that: 1. The power battery adopts the form of four batteries in series, and each battery is connected with a short circuit loop, so that any battery failure can be quickly cut off, but the remaining three batteries can continue to supply power to the whole machine.

[0050] 2. In order to reduce the influence of power battery temperature rise, a water cooling system is integrated, and different flow rates of cooling water are used for cooling according to the different temperature rises of power battery and motor.

[0051] 3. The intelligent control system with high integration is used, which replaces the condition that multiple computers control respectively on traditional helicopters, and uses high integration to avoid the waste of transmission signals caused by multiple transmissions of information.

[0052] 4. The control system of the integrated management computer is integrated with the power distribution system, which not only enhances the control ability of the electrical equipment, but also integrates the energy distribution and control signal to improve the utilization rate and reduce unnecessary waste.

[0053] 5. The high and low voltage power supply system is separated, which reduces the power waste of high voltage system, uses the traditional aviation single-wire power supply system, reduces the weight, and improves the reliability of the electrical system.

[0054] 6. The speed signal of the speed controller is compared with the click speed signal, which can reduce the misjudgment of the integrated management computer to the speed.

[0055] Please refer to Figure 1, in order to complete the all-electric helicopter system design, also for solving the all-electric system design in the more difficult problem of temperature rise, improve system safety and reliability, etc., the present application provides a set of containing water cooling function and high reliability of electrical system design.As shown in the figure, the electrical system is divided into electric power system, water cooling system, intelligent control system and low voltage distribution system, etc.Composition.For accurate description, from the machine control part, high voltage power part, low voltage power part, etc.Three parts are introduced:

[0056] The machine control part, first connect 24V battery, comprehensive management computer and busbar 2 can be connected, the operator controls the refrigeration on the operation of the comprehensive management computer, in turn control power battery, motor and other parts are connected, power battery connection signal is transmitted from the comprehensive management computer to BMS block, at the same time, BMS module collects the single cell voltage, current and battery temperature of power battery and judges whether these data meet the design requirements, and reports the collected information to the comprehensive management computer, and the comprehensive management computer displays the contents on the screen, if the single cell battery appears over temperature, over current and other serious damage to the battery, BMS module will automatically disconnect the abnormal single cell battery, and report alarm information and battery abnormal cut-off information to the comprehensive management computer, in the case of only three power batteries working, if the single cell battery over temperature, over current and other serious alarm signals appear again, BMS module will not remove the abnormal single cell battery, but will report this part of the content to the comprehensive management computer.

[0057] After the power battery is connected normally, the operator controls the motor contactor in the motor controller through the comprehensive management computer control part, the motor controller converts the direct current of the power battery into alternating current, and connects the battery through the motor contactor, at the same time, collects the motor speed, temperature, voltage, current and other information, and reports them to the comprehensive management computer, which judges this part of information and outputs the control output motor speed instruction.The motor speed information is also collected by the rotor speed signal of the rotor speed controller as a reference, and the output motor speed instruction is corrected.

[0058] The comprehensive management computer will connect the water cooling system to cool the power battery or motor according to the lowest temperature of the single cell battery reported by the battery and the preset temperature threshold of the motor temperature.

[0059] The high-voltage power part on the machine adopts a double-wire circuit loop, and the output voltage of the power battery positive terminal is transmitted to the motor controller through a high-voltage box composed of a contactor and a fuse. The motor controller is internally provided with a DC / AC converter, which converts the direct current output by the power battery into three-phase alternating current required by the motor to drive the motor to rotate. The motor drives the rotor to rotate through the transmission part on the machine to provide lift for the helicopter and realize flight. The internal fuse of the high-voltage box will cut off the power battery in the case of abnormal excessive current output by the power battery, thereby achieving the purpose of protecting the battery. The power battery is internally composed of four single batteries connected in series, and each single battery is externally connected with a contactor and a diode. When it is judged that the single battery is overheated, overcurrent or abnormally damaged, etc., the BMS module will control the contactor to be turned on, thereby achieving the effect of short-circuiting the single battery. At the same time, a diode is connected in series, which can avoid the behavior of damaging the battery when the single battery and the short-circuit line form a loop during short-circuiting of the single battery.

[0060] The low-voltage power distribution system on the machine is composed of two busbars 1 and 2 which are both powered by 24V storage batteries and independent of each other. Busbar 1 directly distributes power to key electrical equipment, and different specification circuit breakers are added to the feeder circuit of the power distribution. In the case of short circuit of the electrical equipment, the circuit breaker will be disconnected, thereby avoiding the influence of the abnormal circuit of part of the equipment on the whole machine electrical system network. Busbar 2 is internally provided in the integrated management computer, and distributes power to the electrical load according to the Irat curve through the SSPC power distribution circuit, and has functions such as overcurrent and short circuit protection. The negative end of the electrical equipment adopts the single-wire system of the traditional aviation system and is connected with the machine ground to form a loop.

Claims

1. An electrically powered helicopter electrical system, characterized in that, It comprises an electric power system, an intelligent control system, a water cooling system and a low-voltage power distribution system. The electric power system comprises power batteries, a high-voltage box, a controller and a motor, provides power supply for the whole machine, and transmits power to the rotor through a transmission system to provide lift for the helicopter. The water cooling system comprises a power battery water cooling system, a motor water cooling system, an overflow water tank, an expansion water tank and a radiator. The intelligent control system comprises a comprehensive management computer and a rotor speed controller. The low-voltage power distribution system comprises a 24V storage battery and on-board low-voltage electrical equipment. The power battery is internally connected by four batteries in series, and each battery is connected by a plurality of small batteries in series. Each battery is externally connected with a contactor and a diode. When a battery fails, the BMS sends a shutdown instruction to short-circuit the faulty battery, and the whole machine is powered by the remaining three power batteries. The total positive of the power supply is connected with the high-voltage box, and the total negative is connected with the controller, which provides high-voltage power source for the whole machine. The BMS management module in the power battery collects the capacity, voltage, current and temperature information of each power battery, judges the quality of the power supply, and reports the information to the comprehensive management computer and displays it on the control screen. The power battery connection instruction is given, and is sent out through the comprehensive management computer. The large and small water pumps are power equipment for providing circulating cooling water to the power battery and the motor. The large and small water pump controllers collect the water pump cooling water flow rate and provide power to the water pump, and feedback the collected flow rate to the comprehensive management computer to receive the instruction of the comprehensive management computer to control the water pump flow rate. The controller heat exchanger, radiator and expansion water tank dissipate the heat of the cooling water discharged from the equipment, and the cooled cooling water is transmitted to the controller and motor through the large and small water pumps to cool the equipment. The rotor speed controller collects the rotor speed and reports it to the comprehensive management computer. The comprehensive management computer compares the rotor speed with the motor speed, combines the motor working efficiency and the rotor speed control signal as a reference, and corrects the rotor speed control signal. The comprehensive management computer controls the whole machine system equipment, transmits the collected voltage, current, frequency and speed physical quantities to the comprehensive management computer, and monitors the physical quantities by the comprehensive management computer, and sends control instructions to the equipment.

2. The electric helicopter electrical system according to claim 1, wherein the comprehensive management computer also has a power distribution function, which is based on the busbar input voltage, controls the power distribution of the equipment through the internal control board and protection devices, monitors the current, and implements overcurrent and short circuit protection functions for the equipment based on the Irat curve protection.

3. The electric helicopter electrical system according to claim 2, wherein ​ The on-board low-voltage electrical equipment adopts the single-wire system in traditional aviation, and according to the importance of the power supply of the equipment, the emergency equipment is set to two-way power distribution, and the two-way power distribution is realized by two independent bus bars which are both provided with power by 24V storage batteries, wherein one way is provided with power by 24V storage batteries, and the power is transmitted to the integrated management computer, the motor controller and the power battery BMS module through the bus bar 1 and then connected to the machine ground to complete the first power distribution, and the process is protected by using a circuit breaker, and the other way is provided by the integrated management computer, and the power of the equipment is transmitted through a bus bar in the integrated management computer and named as bus bar 2, and then the control circuit and the power are switched and regulated by the solid-state power controller in the integrated management computer to supply power to the load of the electrical equipment, and the load negative end is also connected to the machine ground to form a loop.

4. An electrically powered helicopter electrical system control method, characterized by, The method is applied to the electric helicopter electrical system of claim 1, and the method comprises: Step 1, turn on the 24V storage battery, the integrated management computer is automatically connected with the bus bar 2, the operator sequentially connects the power battery, the motor controller and the rotor speed controller through the integrated management computer, the BMS module collects, judges the single battery voltage, current and battery temperature information of the power battery and reports them to the integrated management computer; Step 2, when the BMS module collects that the single battery over-temperature and over-current seriously damage the battery, the BMS module will cut off the abnormal single battery by connecting the short-circuit current of the abnormal single battery and report the alarm information and the battery abnormal cutting information to the integrated management computer; Step 3, after the single battery is cut off, the remaining three power batteries continue to work, if the single battery over-temperature and over-current serious alarm signal appears again, the BMS module will not cut off the abnormal single battery, but will report this part of the content to the integrated management computer; Step 4, after the power battery and the motor controller are connected, the motor controller converts the direct current of the power battery into alternating current to drive the motor to rotate and then drive the rotor to rotate, the motor controller collects the motor speed, temperature, voltage and current information and reports them to the integrated management computer, and the integrated management computer judges the information uploaded by the rotor speed controller and corrects the motor speed instruction; Step 5, the integrated management computer will cool the power battery or the motor according to the lowest temperature of the single battery reported by the battery and the preset temperature threshold of the motor temperature to turn on the water cooling system; Step 6, the high-voltage power part on the machine adopts a double-wire circuit loop, the positive terminal of the power battery outputs voltage, which is transmitted to the motor controller through the high-voltage box composed of a contactor and a fuse, the DC / AC converter built in the motor controller converts the direct current output by the power battery into three-phase alternating current required by the motor to drive the motor to rotate, and the motor drives the transmission part on the machine to rotate the rotor to provide lift for the helicopter to realize flight. Step 7, on-board low-voltage power distribution system, composed of two busbars 1 and 2, both powered by 24V battery and independent of each other, busbar 1 directly powers key electrical equipment, and different specifications of circuit breakers are added on the feeder circuit of the power distribution, busbar 2 is built-in on the integrated management computer, overcurrent and short circuit protection functions are realized through the SSPC power distribution circuit, and the negative terminal of the electrical equipment adopts the single-wire system of the traditional aviation system and is connected to the aircraft ground to form a loop.

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