k fuku Posted February 13, 2023 Report Share Posted February 13, 2023 Possibility of Controlling Electric Power Steering by PDM We are considering removing the OEM electric power steering control ECU and controlling it with PDM. We are thinking of activating the main motor based on the steering shaft torque sensor voltage. Quote Link to comment Share on other sites More sharing options...
Biased Opinion Posted February 28, 2023 Report Share Posted February 28, 2023 Just a quick look at various electric power steering solutions would suggest that the amperage required is far above what any single output on the razor PDM could supply. Maybe an ECU controlled solid state relay might be a better solution. Would certainly be alot cheaper than the razor k fuku 1 Quote Link to comment Share on other sites More sharing options...
mapper Posted March 1, 2023 Report Share Posted March 1, 2023 You can use several outputs in parallel to get more current. k fuku 1 Quote Link to comment Share on other sites More sharing options...
k fuku Posted March 3, 2023 Author Report Share Posted March 3, 2023 On 2/28/2023 at 1:45 PM, Biased Opinion said: Just a quick look at various electric power steering solutions would suggest that the amperage required is far above what any single output on the razor PDM could supply. Maybe an ECU controlled solid state relay might be a better solution. Would certainly be alot cheaper than the razor We would like to mount the electric power steering system for mini cars manufactured by Daihatsu, a Japanese manufacturer It requires a maximum of 33A and the ECU master H-bridge will meet the voltage requirements, but we are unable to set up the detailed operation. If possible, RAZR PDM would be ideal. On 3/2/2023 at 6:10 AM, mapper said: You can use several outputs in parallel to get more current. What is the maximum amperage that link's PDM can use in parallel connection? One 25A, two in parallel can be 50A? Quote Link to comment Share on other sites More sharing options...
Mitchell Posted March 5, 2023 Report Share Posted March 5, 2023 The Razor PDM doesn't currently support parallel H-bridge. When driving a motor using H-bridge the maximum continuous current is 25A, however the current can peak higher for a limited time. Is the 33A rating the stall current or rated current of the motor? If so, the normal driving current is normally lower than the stall current so the Razor PDM should be able to drive the motor. On 3/3/2023 at 9:16 PM, k fuku said: We would like to mount the electric power steering system for mini cars manufactured by Daihatsu, a Japanese manufacturer It requires a maximum of 33A and the ECU master H-bridge will meet the voltage requirements, but we are unable to set up the detailed operation. If possible, RAZR PDM would be ideal. k fuku 1 Quote Link to comment Share on other sites More sharing options...
k fuku Posted March 7, 2023 Author Report Share Posted March 7, 2023 On 3/6/2023 at 5:46 AM, Mitchell said: The Razor PDM doesn't currently support parallel H-bridge. When driving a motor using H-bridge the maximum continuous current is 25A, however the current can peak higher for a limited time. Is the 33A rating the stall current or rated current of the motor? If so, the normal driving current is normally lower than the stall current so the Razor PDM should be able to drive the motor. Thanks for the information. I guess the parallel connection was not possible. 33A is the maximum load when lock to lock. I am sorry to hear that, but I will consider using other PDMs for control. Quote Link to comment Share on other sites More sharing options...
mapper Posted March 7, 2023 Report Share Posted March 7, 2023 Here is what the manual says. From my expierence the full 33 amps are reached only for a very short time, so the Razor PDM might handle it fine. On top you can define Inrush current and safety trip time. The hardware is very capable, so I guess it will handle it just fine. Outputs High Power There are 4x high power outputs with a maximum safe inrush current of 80A and a continuous current limit of 25A at 12V. While the maximum safe inrush current is 80A, the maximum measurable current is 60A. The high power outputs each share two pins of the 26-pin super seal connector. They can be used as high-side or low-side drivers, have a max frequency of 10kHz, and can be configured as 4 x half bridges or 2 x full bridges allowing control of devices such as e-wastegates. When in full bridge mode, Output 1 is paired with Output 2 and Output 3 is paired with Output 4. Outputs can be joined together to allow the use of higher current devices. k fuku 1 Quote Link to comment Share on other sites More sharing options...
k fuku Posted March 8, 2023 Author Report Share Posted March 8, 2023 5 hours ago, mapper said: Here is what the manual says. From my expierence the full 33 amps are reached only for a very short time, so the Razor PDM might handle it fine. On top you can define Inrush current and safety trip time. The hardware is very capable, so I guess it will handle it just fine. Outputs High Power There are 4x high power outputs with a maximum safe inrush current of 80A and a continuous current limit of 25A at 12V. While the maximum safe inrush current is 80A, the maximum measurable current is 60A. The high power outputs each share two pins of the 26-pin super seal connector. They can be used as high-side or low-side drivers, have a max frequency of 10kHz, and can be configured as 4 x half bridges or 2 x full bridges allowing control of devices such as e-wastegates. When in full bridge mode, Output 1 is paired with Output 2 and Output 3 is paired with Output 4. Outputs can be joined together to allow the use of higher current devices. Is it correct to recognize 25A x 2 when H-bridge is used in parallel? If so, it is possible. I would like to check the help for RAZOR PDM, but the software does not start because of windows 7 and I had to give up. Thank you very much. Quote Link to comment Share on other sites More sharing options...
Mitchell Posted March 8, 2023 Report Share Posted March 8, 2023 PDMLink was initially intended to support Windows 7 but due to incompatibilities and the outdated nature of Windows 7, PDMLink doesn't support Windows 7. You can find an online version of the PDMLink help manual at: User Manual | LinkECU Documentation Centre (link-user-wiki.herokuapp.com) When using an output in H-Bridge mode, the current is running in series through each pin so the current capacity is the same as a single high power output. A way to ensure the current limit isn't exceeded is to limit the range of duty cycle in the H-Bridge. This shouldn't limit the range of motion of the motor but would reduce the torque slightly at the end stops. mapper 1 Quote Link to comment Share on other sites More sharing options...
k fuku Posted March 9, 2023 Author Report Share Posted March 9, 2023 21 hours ago, Mitchell said: PDMLink was initially intended to support Windows 7 but due to incompatibilities and the outdated nature of Windows 7, PDMLink doesn't support Windows 7. You can find an online version of the PDMLink help manual at: User Manual | LinkECU Documentation Centre (link-user-wiki.herokuapp.com) When using an output in H-Bridge mode, the current is running in series through each pin so the current capacity is the same as a single high power output. A way to ensure the current limit isn't exceeded is to limit the range of duty cycle in the H-Bridge. This shouldn't limit the range of motion of the motor but would reduce the torque slightly at the end stops. It was mentioned that windows 7 will be supported in the future at the software download location, but is there any plan to support it? Thank you for the PDM manual. I will test the 25A limited operation with another H-bridge model and then think about installing RAZOR. Quote Link to comment Share on other sites More sharing options...
Mitchell Posted March 9, 2023 Report Share Posted March 9, 2023 3 hours ago, k fuku said: It was mentioned that windows 7 will be supported in the future at the software download location, but is there any plan to support it? We initially intended to support Windows 7, but after further testing on Windows 7 we found that we wouldn't be able to continue development of PDMLink and maintain compatibility. Since then, the decision has been made to discontinue attempts to support Windows 7 k fuku 1 Quote Link to comment Share on other sites More sharing options...
k fuku Posted March 9, 2023 Author Report Share Posted March 9, 2023 2 hours ago, Mitchell said: We initially intended to support Windows 7, but after further testing on Windows 7 we found that we wouldn't be able to continue development of PDMLink and maintain compatibility. Since then, the decision has been made to discontinue attempts to support Windows 7 Okay, thank you very much. ,. Quote Link to comment Share on other sites More sharing options...
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