SCADA Maintenance Manual

Transcription

1 SCADA Maintenance Manual ECE 492 Spring 2013 Latest Revision: 16 May 2013 Prepared by: Sabbir Siddiqui Abstract This manual is to be used to maintain or troubleshoot the SCADA system as built by the Spring 2013 LFEV-ESCM team.

2 SCADA MAINTENANCE MANUAL 1 Introduction The purpose of the SCADA is to collect cell data from the BMS boards, display them on the screen, monitor system safety based on boundary conditions, and log the data. The SCADA also controls the Safety Loop and Load Controllers for when the system is in discharge mode. The SCADA mainly consists of the 4D ulcd-43pt Display Module with a PICASO processor which contains all the code for controlling and monitoring system states as well as displaying the data. Other components inside the box are the DC to DC converter, and the protoboard circuit for the relays. The system is functional for discharging, however there are some issues that may come up. System Configuration The SCADA system, as it stands, is configurable to display up to 8 cells for 1 pack. The system may be expanded to support displaying data for up to 4 packs. The boundary values for cell voltages, temperatures and current are also configurable through the text file CONFIG.txt, which is to be placed in the microsd card inside the Display Module. The file CONFIG.txt must contain a line in the following format: pack 1 cell 3 minv 260 maxv 400 mint 010 maxt 070 maxi 350 The names and variables are each separated by a white space. The word pack starts from the very beginning of the file. The variable pack is meant to specify the number of packs in the system. The variable cell is meant to specify the number of cells per pack in the system. The variables minv and maxv are used to specify the boundary conditions for cell voltages. The numbers are in format X.XX ; as shown above, the values signify the boundary conditions for voltages as 2.60V and 4.00V respectively.

3 SCADA MAINTENANCE MANUAL 2 The variables mint and maxt are used to specify the boundary conditions for cell temperatures (in Celcius). The numbers are in the format XXX ; as shown above, the values signify the boundary conditions for temperatures as 10C and 70C respectively. The variable maxi is used to specify the maximum current allowed through the packs. Programming the Display Module The programming environment for the Display Module firmware can be downloaded from the following website: The module to choose is the ulcd-43pt, and the environment is ViSi. The above website also contains documentation on the language references. The language is similar to C or C++, with subtle differences. To download the code on to the module: - Connect to the computer via a USB to TTL Cable, which may also be purchased from the website (if not already available). - In the Project tab, choose Flash for Destination. Click on Com nload on the upper right corner of the window to compile the code and download it on to the module. - To save the image files for the display screen buttons, indicators, etc. the program will prompt to save a.gci and.dat file on to an external drive. Connect a microsd card to the PC, and select that drive to save the files to.

4 SCADA MAINTENANCE MANUAL 3 - Make sure the file CONFIG.txt as described above is present in the same microsd card. Maintaining the Protoboard Circuit A schematic of the protoboard circuit can be found in the following link: - The Yellow LED indicates the state of Safety Loop switch on the SCADA s end (on for closed) - The Red LED indicates the state of the Load Controller Isolation Relays (on for closed) - The Green LED is for the Safety Loop monitor, and is on if the Safety Loop is closed. The relays used are single coil multiple drive relays made by Panasonic, model AG The relays are not manufactured anymore. If there is an issue with the relay not functioning, the relay has to be replaced with a suitable one, and the connections on the protoboard have to be remade. The schematic should be sufficient to rewire the circuit. Maintaining the Display Module The Display Module has a lot of limitations because of its processor. Here are some of them:

5 SCADA MAINTENANCE MANUAL 4 - The only system variable is var which is a 16 bit variable. In case of integers it is signed. Arrays of var type can be used as well. - The processor can handle up to 16 bit calculations, and will wrap around if results are over the maximum value. - The processor cannot handle floating point calculations, so all numbers have to be in integers. In the system as it stands, there are a few issues to be addressed: - If the system goes to an error screen, it shows LED s as green or red to indicate which part of the system caused the error. However, those are controlled by variables which keep updating, so if the error was momentary, it will not show on the screen. The variable values need to be latched for the error screen. - The hardware is very fragile. If there is any change with the code in terms of display buttons, or LED s or images, etc, the code for those images/objects have to be regenerated (using the Paste Code feature) with appropriate pointers or handlers. Then the code has to be recompiled and downloaded onto the module. - Also because of the fragile hardware, the SCADA screen may freeze if the BMS is plug is disconnected mid-operation. In this case, the Reset button on the panel will not work. The system has to be hard-reset by turning the power switch on and off. This may be due to the I2C lines, SDA and SCL which are digital pins on the display module with built in pull up resistors. This is not mentioned in the documentation, but that may be a possible fix. - The odometer does not have a proper relationship with the speed value. The system timer may be used to obtain a sense of time. Again, this is limited to the 15 bit maximum value.

6 SCADA MAINTENANCE MANUAL 5 Expanding Code for Multiple Packs and other features Cell voltages and temperatures are stored in two arrays packcellv and packcellt which is indexed from 0. The function getcellnum() takes the 0-indexed number of the pack and cell, and converts that into a single integer that is used to represent a cell. o E.g. packcellv[9] will contain the voltage value for Cell 2 in the 2 nd Pack. o getcellnum(1,1) will return 9. The functions updatedisplay, processtouch need to be updated to include functionality of screens for packs 2, 3 and 4. The Display module has two Serial I/O pins which may be used for add-on modules for extra sensors or an Arduino.