High-power combined load and airborne power supply matching system

Abstract

The utility model belongs to the technical field of aviation electrical, and discloses a high-power combined load and airborne power supply matching system, which comprises two generators, two rectification power supplies, a 270V bus bar and a rear-end load, the two generators respectively supply power to the two rectification power supplies, the two rectification power supplies are connected through current sharing control, and the 270V bus bar is connected with the rear-end load. The two rectification power supplies respectively supply power to the 270V bus bar, and the 270V bus bar supplies power to a rear-end load. The matching system of the high-power combined load and the airborne power supply has advancement, is applied to the field of domestic special aircrafts for the first time, improves the technical content of matching of the high-power combined load and the airborne power supply system, and lays a solid technical foundation for successful development of certain aircrafts.

Description

Technical Field

[0001] The utility model belongs to the field of aviation electrical technology, and relates to a matching design of a high-power combined load and an airborne power supply system, and specifically relates to a high-power combined load and an airborne power supply matching system. Background Art

[0002] The mission system load of a certain type of flight platform is a high-power airborne towing antenna system load. Its long antenna motor drive unit and short antenna motor drive unit are two electric winches, with power consumption of 43kW and 16kW respectively. The two electric winches are motor loads, and when the airborne towing antenna system is towing the antenna, the two winches will work at the same time. In addition, the power supply power requirements of power equipment such as power amplifier cabinets reach hundreds of kW. Such a high-power combined load, including motor loads, resistive loads and capacitive loads, will generally generate a starting impact current several times the rated load during startup, causing the grid voltage to drop, and even causing undervoltage or overcurrent protection of the carrier power system, affecting the completion of the airborne mission. Summary of the invention

[0003] Therefore, the utility model proposes a high-power combined load and airborne power matching system to solve the matching problem between the high-power combined load and the airborne power system.

[0004] The technical solution of the utility model is as follows:

[0005] A high-power combined load and airborne power supply matching system includes two generators, two rectifier power supplies, a 270V bus bar and a rear-end load. The two generators supply power to the two rectifier power supplies respectively, the two rectifier power supplies are connected through current sharing control, the two rectifier power supplies then supply power to the 270V bus bar respectively, and the 270V bus bar supplies power to the rear-end load.

[0006] Furthermore, the rear-end loads include a motor load, an energy-consuming circuit, a resistive load and a capacitive load, and the rear-end loads are connected in parallel.

[0007] Furthermore, it includes a peak-shifting time-sharing starting module, which connects and controls the peak-shifting starting of the motor load, energy-consuming circuit, resistive load and capacitive load.

[0008] Furthermore, a variable frequency starting module is provided in the motor load to reduce the impact current peak at startup and reduce the impact on the power grid when the system starts.

[0009] Furthermore, the rectifier power supply includes a miniaturized dry-type eighteen-pulse rectifier transformer and a plurality of rectifier bridge circuits, which convert the airborne medium-frequency AC power supply into a high-power high-voltage DC power supply.

[0010] Furthermore, a balancing reactor is provided on the DC side of the rectifier power supply to improve the current sharing among the three groups of windings on the secondary side of the eighteen-pulse transformer.

[0011] The beneficial effects of the utility model are as follows:

[0012] 1. The matching system of the high-power combined load and the airborne power supply of the utility model is advanced and is applied to the field of domestic special aircraft for the first time. It improves the technical content of the matching of the high-power combined load and the airborne power supply system and lays a solid technical foundation for the successful development of a certain type of aircraft.

[0013] 2. This system will improve the stability of the aircraft power supply, have little impact on the power grid, greatly reduce the probability of undervoltage or overcurrent protection of the carrier power supply system, reduce the pollution of the rectifier output harmonics to the AC side power supply, ensure the normal power supply of the carrier load and the test results of the main performance indicators such as AC input current harmonics meet the Class B power supply requirements in GJB 181-1986 "Aircraft Power Supply Characteristics and Requirements for Electrical Equipment". BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solution of the implementation method of the patent of the present invention, the following is a brief introduction to the drawings required for use in the implementation method. It should be understood that the following drawings only show certain embodiments of the patent of the present invention and should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 This is a schematic diagram of a high-power combined load and airborne power supply matching system of the utility model;

[0016] Figure 2 It is a block diagram of the power supply composition of a high-power combined load system;

[0017] Figure 3 This is a test model diagram for the power supply matching between a large-power combined load system and a ground power grid model. DETAILED DESCRIPTION

[0018] This section is an embodiment of the present invention, which is used to explain and illustrate the technical solution of the present invention. In the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0019] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the orientations or positional relationships in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or case referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implying the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be interpreted in a broad sense, for example, it can be a fixed connection, a detachable connection or an integrated connection; it can be a mechanical connection or a point connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0021] Embodiment 1:

[0022] A high-power combined load and airborne power supply matching system includes two generators, two rectifier power supplies, a 270V bus bar and a rear-end load. The two generators supply power to the two rectifier power supplies respectively, the two rectifier power supplies are connected through current sharing control, the two rectifier power supplies then supply power to the 270V bus bar respectively, and the 270V bus bar supplies power to the rear-end load.

[0023] The rear-end loads include motor loads, energy-consuming circuits, resistive loads and capacitive loads, and the rear-end loads are connected in parallel.

[0024] It includes a peak-shifting time-sharing starting module, which connects and controls the peak-shifting starting of motor loads, energy-consuming circuits, resistive loads and capacitive loads.

[0025] A variable frequency starting module is installed inside the motor load to reduce the impact current peak during startup and reduce the impact on the power grid when the system starts.

[0026] The rectifier power supply includes a miniaturized dry-type eighteen-pulse rectifier transformer and multiple groups of rectifier bridges, which convert the airborne medium-frequency AC power supply into a high-power high-voltage DC power supply.

[0027] A balancing reactor is provided on the DC side of the rectifier power supply to improve the current sharing among the three sets of windings on the secondary side of the 18-pulse transformer.

[0028] Embodiment 2:

[0029] When starting, high-power combined loads (including motor loads, resistive loads and capacitive loads, etc.) generally generate a starting impact current several times that of the rated load, causing the grid voltage to drop, and even causing the carrier power system to be undervoltage or overcurrent protected, affecting the completion of the onboard mission. Therefore, in order to reduce the impact of the large-power combined loads on the onboard power system, reduce the pollution of the rectifier output harmonics to the AC side power supply, and ensure that the normal power supply of the carrier load and the main performance index test results such as the AC input current harmonics meet the Class B power supply requirements in GJB 181-1986 "Aircraft Power Supply Characteristics and Requirements for Electrical Equipment", the present invention proposes a design method for matching large-power combined loads with the onboard power system by studying the large-power combined load impact current control technology, the onboard large-power medium-frequency rectification technology and the large-power rectifier power supply parallel power supply technology, so as to solve the matching problem between the large-power combined loads and the onboard power system.

[0030] The present invention is realized by the following technical solutions: (1) In order to reduce the impact of high-power combined loads on the airborne power supply system, the motor load is powered by a transformed secondary power supply (through the bus, the 270V bus power supply is called secondary power supply), reducing the direct impact on the AC power supply system, and when the high-power combined load system is powered on, the motor load, resistive load and capacitive load are started in staggered and time-sharing mode, which effectively reduces the impact of the high-power combined load on the AC generator when starting. In addition, the motor load in the high-power combined load system adopts variable frequency starting measures to reduce the impact current peak at startup and reduce the impact on the power grid when the system starts; (2) In terms of rectifier power supply, based on a miniaturized dry-type 18-pulse rectifier transformer and a multi-group rectifier bridge design, an airborne 18-pulse medium frequency isolation rectifier method is proposed to realize the function of converting the airborne medium frequency AC power supply into a high-power high-voltage DC power supply, while taking into account the isolation protection of the platform AC power supply. A balancing reactor is designed on the DC side to improve the current balance between the three sets of windings on the secondary side of the 18-pulse transformer, solving the problem of local overheating of the transformer. (3) In order to meet the power supply requirements of large-power combined load systems, a DC parallel power supply method for large-power rectifier power supplies is proposed. Two sets of AC power supplies are connected in parallel on the DC side through rectifier power supplies to supply power to the motor load at the same time. The design of AC reactor improves the load balance when the two sets of rectifier power supplies are connected in parallel, reducing the maximum AC power load to 56% of that of a single power supply. The power supply of large-power combined load systems can be flexibly configured through parallel switches, supporting dual power supply parallel connection, dual power supply independent operation, and single power supply multiplexing multiple operation modes, thereby improving the power supply reliability of large-power combined load systems. A parallel buffer circuit is designed to effectively suppress the instantaneous impact current when the rectifier power supply is connected in parallel.

[0031] When designing the power distribution of the high-power combined load system, in order to minimize the impact of the high-power combined load on the power grid and airborne equipment when starting, the high-power combined load is powered by two independent power supply channels. The power supply relationship of the four independent power supply channels of the AC power supply system is as follows: the AC power supply system channels II and III supply power to the high-power combined load system, and the AC power supply system channel I is the power supply channel for the carrier load. Therefore, even if there is a starting current impact when the high-power combined load system starts, it is limited to the power supply system channels II and III, and will not affect the normal power supply of the carrier load of channel I.

[0032] In order to reduce the impact of high-power combined loads on the onboard power supply system, the high-power combined loads are powered by a transformed secondary power supply, which can reduce the direct impact on the AC power supply system. The high-power combined load system uses two 18-pulse transformer-rectifier ATRUs to convert the 115V AC power supply of the AC power supply system II and III channels into 270V high-voltage DC power supply, and then output it to the motor load, resistive load and capacitive load respectively. The two AC generators and transformer-rectifiers can simultaneously bear the impact current of the high-power combined loads at startup. In addition, when designing the power-on program of the high-power combined load system, the motor load, resistive load and capacitive load adopt staggered and time-sharing start-up, which effectively reduces the impact of the high-power combined load on the AC generator when starting. In addition, the high-power combined load adopts variable frequency starting measures to reduce the impact current peak at startup and reduce the impact of the motor on the power grid when starting.

[0033] The power supply of the high-power combined load system is connected to the onboard AC power supply, the onboard normal 28V power supply and the onboard emergency 28V power supply, and supplies power to the DC 270V power equipment, DC 28V power equipment, and AC 220V / 50Hz power equipment in the high-power combined load system. Among them, the aircraft platform is equipped with an AC contactor, and manual control is used to realize the on-off control of the AC power supply. The normal 28V power supply in the switchboard can accept the on-off control of the control console button command. The onboard generator has an output protection function. The switchboard is equipped with a DC circuit breaker for line protection. The on-off control and protection of the emergency 28V power supply are the responsibility of the platform.

[0034] The transformer-rectifier unit converts the 115V / 400Hz AC power provided by the onboard generator into the 270V DC power required by the high-power combined load system. The designed power capacity is 50kVA, and the root mean square value of the total distorted current of the AC input does not exceed 10% of the effective value of the fundamental current. The AC contactor at the 115V / 400Hz AC input end is configured by the onboard platform.

[0035] The high-voltage DC power distribution unit realizes the access and parallel connection of two transformer and rectifier units to supply power to high-power loads, with power supply powers of 35kW, 16kW, and 43kW respectively, and has protection functions such as overvoltage, undervoltage, and overcurrent protection. The high-voltage DC power distribution unit can also switch the transformer and rectifier units and loads according to the needs of the high-power combined load system to improve power supply stability.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A high-power combined load and airborne power matching system, characterized in that: It includes two generators, two rectifier power supplies, a 270V bus and a rear-end load. The two generators supply power to the two rectifier power supplies respectively. The two rectifier power supplies are connected through current sharing control. The two rectifier power supplies then supply power to the 270V bus respectively. The 270V bus supplies power to the rear-end load.

2. A high-power combined load and airborne power matching system according to claim 1, characterized in that: The rear-end loads include motor loads, energy-consuming circuits, resistive loads and capacitive loads, and the rear-end loads are connected in parallel.

3. A high-power combined load and airborne power matching system according to claim 2, characterized in that: It includes a peak-shifting time-sharing starting module, which connects and controls the peak-shifting starting of motor loads, energy-consuming circuits, resistive loads and capacitive loads.

4. A high-power combined load and airborne power matching system according to claim 2, characterized in that: A variable frequency starting module is installed inside the motor load to reduce the impact current peak during startup and reduce the impact on the power grid when the system starts.

5. A high-power combined load and airborne power matching system according to claim 1, characterized in that: The rectifier power supply includes a miniaturized dry-type eighteen-pulse rectifier transformer and multiple groups of rectifier bridges, which convert the airborne medium-frequency AC power supply into a high-power high-voltage DC power supply.

6. A high-power combined load and airborne power matching system according to claim 1, characterized in that: A balancing reactor is provided on the DC side of the rectifier power supply to improve the current sharing among the three sets of windings on the secondary side of the 18-pulse transformer.

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