About TAPASThe Siemens SDI TAPAS is a 48V GaN (Gallium Nitride) based three phase inverter board with onboard filters, expected to change the way people approach power electronics. The design choice allows for a high switching frequency, while producing a smooth output waveform. The unique combination of high bandwidth and smooth output makes TAPAS to some degree universal, giving rise to applications ranging from robotics to power conversion, making the inverter truly software configurable. The TAPAS board is designed as an educational platform that addresses enthusiasts as well as experts at universities and the industrie. The development of the TAPAS board is community driven. Together with open-source code examples and extensive documentation we made TAPAS as accesible to the community as possible.
Siemens SDI TAPAS Community Inverter
Normally, when a drives inverter is presented, a small to medium size industrial motor connected turning without load can be seen. In contrast to this standard-case, we decided to use a hobby motor in an application with medium to high speed and load. As an impeller is applied to the motor for mechanical loading it, with increasing speed the power consumption increases as well as the disturbances caused e.g. by turbulent air flow. This project shows, that TAPAS can provide a stable speed control of a connected motor even under varying load.
Hovering a Beach Ball with an Impeller Turbine
Highlights
- Operates at any DC Power supply from 24 to 30V
- Firmware based on InstaSPIN from Texas Instruments, restructured and modified to enable high switching frequencies
- PWM switching at 350kHz yields effective filtering of the output voltages
- standalone operation with a switch for enabling and disabling the motor and a potentiometer to set the demanded speed
This is an implementation of motor control using the special capabilities of GaN and TAPAS. By switching at a freqeuency of 350kHz, the current ripple is going low and the size of inductors and capacitors that are applied to implement an analog LC-filter-network can be reduced, as it is done on TAPAS. In the end, a sensorless FOC speed control of the connected BLDC-motor is realized, which is as stable and accurate, that an air filled water ball can hover in the airstream of the connected impeller.
Impeller ChangeSun 120 EDF driven by a Hacker SKALAR8 V2- 2300KV BLDC motor
- Impeller ChangeSun 120 EDF driven by a Hacker SKALARB V2 - 2300KV BLDC motor
- sensorless FOC speed-controlled by TAPAS
- Using a potentiometer connected to an analog in of TAPAS for the speed-setpoint
- Using a switch connected to a digital in of TAPAS to enable and disable the motor
- Well controlled speed allows an air-filled water ball hovering in a stable position in the air flow of the impeller
- PWM switching frequency: 350kHz
- FOC execution frequency: 22kHz
- Current controller execution frequency: 22kHz
- speed controller execution frequency: 1kHz
- speed trajectory execution frequency: 1kHz
Happy flying! :)
Comments