LR-01 System Drive Core
How It Works
4 drivers in hotswap-style drive bay
One Per Rotor
Each rotor has a dedicated 22.5kW rotor controller, supporting a nominal input voltage of 55V. This power limit theoretically can be pushed as high as the most powerful SOT-227-4 FET and shunt resistors on the market. However, due to thermal limitations, this may prove difficult and problematic.
Drive core cooling ports
Liquid and Air Cooling
With so much power and therefore heat generation, it is necessary for the drive core to receive adequate cooling. The LR-01 provides air cooling to the internal PCB components and microcontrollers, while the 6 liquid cooling ports are dedicated to the power FETs and resistors.
A single drive core module
Modular Design
The drive core comprises of individual modules, which follow the hotswap-style design found on many server chassis’. While the hotswap functionality is unused and would quite frankly be catastrophic, the geometry allows for easy replacement, repairs, and possible reprogramming/debugging of each module individually.
The PCB (pardon the terrible 3D model)
Robust Control
Because it’s controlling the main rotors of a drone, stable and reliable control is a requirement. With ample processing power, thermal inputs, voltage and current monitoring, and external communications, each drive core module is more than capable of providing power to the main rotors. It even includes a built in TFT display to show status codes and other useful diagnostic data!
Electrical contacts
Electrically Capable
In order to provide 22.5kW, the electrical contacts for the DC input as well as the motor output drive lines are made of solid copper busbars. This allows a rigid electrical bus that can also provide extreme amounts of current. The connections are made via 6mm copper bolts. Additionally, the interface provides another smaller connector for CAN bus, UART, two thermistor analog signals, and hall effect sensor signals.
Liquid cooling heatsinks
Powerful Cooling
To be more than enough for even overloaded conditions, each core’s design incorporates triple liquid radiator modules. These each contain numerous cooling fins that effectively sink heat from the primary heat sources in each module. Because of this, the driver should have no problem handling even larger loads, including upgraded electrical power components. Thermal simulation and real world testing pending.
Specifications
TI TMS320F28030PNT
Main microcontroller
TI DRV8353SM
3-phase motor gate driver
SOT-227-4 Footprint
Motor drive FETs and shunt resistors
ILI9225 TFT Display
To show status and diagnostic data
