Product Introduction

The middle-large size unmanned aerial vehicle (UAV) power management systerm is composed of EMI filter circuits, SSPC intelligent power control switches, MCU power management control circuits, communication circuits, detection circuits, cases and aviation connectors, etc.

As a critical component of unmanned aerial vehicles (UAVs), the reliability of the power management system plays a vital role in ensuring the safe and autonomous operation of UAVs. By the power management systerm can realize the intelligent control and management of the entire power of unmanned aerial vehicles (UAVs), reasonable distribute the power of UAVs, and improve the flight reliability of UAVs. The power management systerm is responsible for the required power switching function management and status monitoring, etc.

The BPMS3000 series unmanned aerial vehicle (UAV) power management systerm converts the high-voltage DC power supply into a DC28V low-voltage DC power supply，providing power for the aircraft's avionics equipment and serving as the main power source for the aircraft's low-voltage busbar. The emergency power supply is responsible for providing power to the entire machine's emergency system when the high-voltage power supply fails, enabling the emergency return and landing of the unmanned aerial vehicle (UAV). The emergency power supply is used in parallel with the high-voltage and ground power supply. The power input and output are switched and controlled by the SSPC intelligent power switch to meet the power supply requirements of aircraft in different working modes. Ground debugging is powered by the ground power supply. During normal flight, the high-voltage power is converted into DC28V through the DC-DC conversion module to supply the full-aircraft. When the DC-DC conversion module failure, it is powered by a low-voltage lithium battery pack. The MCU power management control circuit is responsible for receiving instructions from the flight control computer, monitoring the operation status of the power management system, the power system control, protection and display, and processing various signals, transmitting data and switching functions, etc., to meet the power needs of the aircraft under various load conditions.

Operating Principle

Distribution management system composition and principle diagram as Figure 4 shows. It is composed of a DC/DC power conversion module, SSPC intelligent power switch, MCU control unit, communication circuit, detection circuit, casing and aviation connector, etc.

Functions of the Distribution Management System

1. Ground Power Supply for Aircraft

a) Connect the ground power supply to the aircraft power grid.

b) When the polarity of the ground power supply is reversed, it can prevent the ground power supply from being connected to the aircraft power grid and protect the on-board power grid.

c) When the ground power supply is connected, the high-voltage power supply is automatically disconnected from the aircraft power grid, and at the same time, it switches to the ground power supply to prevent the ground power supply from being connected in parallel with the aircraft power supply.

2. High-voltage Power Supply Conversion and Grid Connection

a) During the period of the airborne high-voltage power supply, the DC/DC convert module outputs a 28V DC voltage and connect to the aircraft power grid. At this time, the ground power supply is disconnected from the aircraft power grid.

b) During the period of the airborne high-voltage power supply, the power management system is equipped with protection functions such as input reverse connection protection, input/output overvoltage and input/output undervoltage protection, load short-circuit protection, and overcurrent protection, etc. When a fault occurs in the airborne high-voltage power supply, the power management system reports the fault status to the flight control computer and automatically connects the airborne lithium battery pack (emergency power supply) to the aircraft power grid, disconnecting the normal busbar power supply.

c) When the airborne high-voltage power supply returns to normal, disconnect the power supply of the airborne low-voltage lithium battery pack (emergency power supply) and restore to the high-voltage power supply status. The airborne high-voltage power supply is reconnected to the aircraft power grid through the MCU control circuit.

3. Emergency Power Supply with Low-voltage Lithium Battery Packs

a）In ground operation state, when the ground power supply is not supplying power to the aircraft and the airborne high-voltage power supply is not working, the aircraft's power grid can be powered by the airborne low-voltage lithium battery pack.

b) When the airborne high-voltage power supply fails, as an emergency power source, the airborne low-voltage lithium battery pack automatically connects to the aircraft power grid and automatically connect to the aircraft power grid for emergency busbar power supply, at the same time, disconnect the power supply of the normal busbar.

4. Power Conversion

a）When the 28V ground power supply is normal, the power management system will connect the ground 28V power supply to the aircraft's power grid preferential to keep power.

b）When the ground 28V power supply is disconnected, the power management system converts the DC high-voltage power supply (DC650V ) of input into 28V DC voltage, and power to the aircraft's power grid simultaneously.

c）When the DC high-voltage power supply (DC750V) fails, the power management system will turn off the high-voltage power supply through the enable terminal of the module automatically. Meanwhile, the low-voltage lithium battery pack is connected to the aircraft power grid automatically for power, and the removable equipment(normal busbar) is disconnected to ensure the power demand of the normally open load (emergency busbar) and guarantee the safe return of the aircraft.

d）The above Power switching occurs after the power management system receives the operation command issued by the flight control computer, realizing the priority switching function of the power supply. When the flight control computer does not send a startup command, all power supplies will be cut off by the power management system.

e）When the control circuit MCU of the power management system fails, low-voltage power manager automatically connects the 28V lithium battery pack to power the subsequent equipment.

5. Power Protection and Fault Handling

a) When overcurrent or short circuit faults occur in the subsequent electrical equipment, the power management system will be protected by the SSPC intelligent power switch to prevent damage to the power management system due to the load short circuit or long-term overload.

b) When the internal power conversion circuit occurs fails of the power management system, the emergency power is converted to the 28V power grid for aircraft through the power manager to maintain the power supply for the emergency system.