Method and Apparatus for Data Processing and Acquiring High Speed Data of Electric Drive System using RS485 and MATLAB Functionality Based Developed Serial Reader Graphical User Interface Tool
2022-26-1176
05/26/2022
- Event
- Content
- The Electric Drive System implemented in more electric aircraft architecture cover one of the applications like engine start up driving the starter generator machine in motoring mode for engine startup and voltage regulation from the starter generator in power generation mode. Electric Drive System undergoing the mode transitions through operating mode change requirements to perform all the operation defined by application either motor or generator operation. In the development of these controls, the conventional modeling and tuning will become tedious and time consuming. Multiple software updates and model updates are required. Our proposed method ties the models and allows temporary controls parameters update loads to the Electric Drive System for the real time testing. Electric Drive System software modifications are required to investigate field issues while integrating Starter Generator machine with the end application. The investigation requires high speed data acquisition of the internal Electric Drive System Control data and measurements while operating in the engine start that last for 20 seconds. Although the Electric Drive System has built-in capability to store the data in RAM and transfers to the Non-Volatile Memory (NVM) at the Waiting State condition, data capturing capabilities are limited to the sizes of RAM and NVM and slow writing cycle of the NVM. If the Electric Drive System captures in the range of 10 msec of the operating data, it is not suitable for troubleshooting the system integration issues that requires tens of seconds of data. The Electric Drive System is connected to a laptop computer equipped with a high-speed USB to RS485 converter, where this interface is used for system integration investigation only. The modification on software is for data logging of variables for controls and measurements during starter generator machine (S/G) operating as starter motor for engine start. The data is output from RS485 port of the Electric Drive System to a laptop computer. The computer stores the Electric Drive System data into the computer memory and hard drive in the real time. This implementation consists of: a) Electric Drive System SW modifications that outputs the data to the RS485 port when operating in the engine start mode, and b) develop a MATLAB apps to read and plot the acquired data on the laptop computer. The MATLAB apps on the computer can set the length of the data acquisition and selected the data to be stored on the computer. These two software tools resolve the issues with the memory size limitation and slow NVM write cycle in the Electric Drive System for data storage for failure investigation and performance analysis. The user can read and analyze the acquired data for the full engine start cycle on the computer. The plotted data on the laptop can be used for tuning the controls and demonstrating the performance improvements to customers. In addition, the tools can allow user to update the control parameters for a temporary change in the field testing. After the controls parameters are finalized in the tests, the software will be updated accordingly. Technical benefits achieved through this method: a) Electric drive system machine control parameters can be uploaded to the controller for temporary operation in order to validate the performance, operation and controls tuning b) Data processing and acquiring high speed data with high resolution. c) Ease of tuning, analysis, debug of the controller since all internal machine control parameters are accessible. d) Feasibility to configure multiple number of output data parameters channels. e) Ease of graphical user interface to visualize all required waveforms. f) Ease of use at customer or field location, even though customer site is not equipped for the testing and performance analysis of the electrical systems g) Cost effective solution, which requires minimal software change only. h) Port data from internal Electric Drive System variables and measurements to computers for controls tuning, and performance validation. Cost Effective Solution: a) Cost effective solution for control tuning, where the Matlab apps is tailored for on-screen measurements. b) Data acquisition system not required, while testing in the customer sites or less equipped testing environments. c) Ease of debugging field issues, as no dependency on data acquisition system. d) In the application of Electric Drive System , no hardware change required on the existing LRUs. This does not affect the system weight, size and recurring cost. e) Productivity improvement as system testing performed at much faster rate. This paper presents a design approach that integrate the troubleshooting, modeling and tuning through the high speed communication port and the software capability of the controller. where this new capabilities support the system testing and tuning at the customer sites. This new approach uses only a laptop computer equipped with the high speed communication port for the on site testing, which can acquire the test data from the controller for analysis and update the control parameters for the real time testing.
- Citation
- SAKINALA, K., Kashireddy, D., Mani, S., and Cheng, L., "Method and Apparatus for Data Processing and Acquiring High Speed Data of Electric Drive System using RS485 and MATLAB Functionality Based Developed Serial Reader Graphical User Interface Tool," SAE Technical Paper 2022-26-1176, 2022, .