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  1. pattiane

    How to implement a zigBee network

    Hi All, I would like to use a ZigBee network for a home automation. I read all the literature on the web. But there is some silly questions that puzzle me. For instance, if I need to install a lighting system, e.g. 3 light switches.. 1/ Do I need 3 ZigBee enddevices + 1 Zigbee Coordinator or...
  2. pattiane

    Reduce overshoot with PI

    The problem was from the design of PI with Simulink blocks. But I still don't understand why this design works with the first set-up and not with the second set-up, which is mine. In fact,using PI as a transfer function has resolved the problem, in my global system.
  3. pattiane

    Reduce overshoot with PI

    Skogsgurra, Ok, let's say that I was able to tune the controller using SISOtool, which enables to find pole and zero of the controller. In PI case: Kp (1+ Ki/s) = K( s + Ki) / s with Ki=1/Ti Ki is the zero of the plant. So I was to find Ki and Kp via SISOtool.That's all.
  4. pattiane

    Reduce overshoot with PI

    Hi All, Yes, it is Skogsgurra. Ive resolved my problem yersteday... The source of problem was the used design of PI controller. I didn't use a normal controller, the design was slight different. Once tuned the PI using SISOTOOL(Simulink GUI), Ive taken the transfer function of PI from that...
  5. pattiane

    Reduce overshoot with PI

    Hello skogsgurra, About Rd in not working system,it is high. Actually, this damping resistor is calculated theoritically by taking into account resonance frequency and capacitor: Rd= 1/3 * 1/ (OMEGA_res.C) But it is true that in real, it should be very small about mOhm. But I...
  6. pattiane

    Reduce overshoot with PI

    Yes, but an overshoot with 50% it isn't tolerable!
  7. pattiane

    Reduce overshoot with PI

    Some details: 1/ LCL = LC filter + L (transformer) Rd = damping resistor in serial with C L are not ideals. Ri is the intern resistance of Li, inverter side inductance Rg is the intern resistance of Lg, inverter side inductance Li = 0.45mH Lg = 0.5mH C = 9.4uF Rd=1.6 Ohm...
  8. pattiane

    Reduce overshoot with PI

    Not exactly...
  9. pattiane

    Reduce overshoot with PI

    LCL: It is two reactors and a capacitor in-between. Basically the LCL filter is connected to the grid, the aim is to control the current. the problem is independant of Id or Iq, the problem is the for a plant (LCL) controlled by a PI, there is some overshoot when parameters change i.e. when...
  10. pattiane

    Reduce overshoot with PI

    Hi all, I am struggling with PI controller to control a curretn controller.The control is in discrete time. Basically, i have a set-up with an inverter and LCL filter. The idea is to control, using dSPACE, the current in d and q axis measured in the output of the LCL filter. What I'm...
  11. pattiane

    Overcurrent Danfoss

    Hi All, The cause of the overcuurent was the wrong connection of the LC filter in inverter output (in CL filter)!!! Electrician's problem! I wonder now why I don't have ant sinusoidal voltages at the filter output. It'd be normally sinusoidal, should it? I wonder whether it's insignifiant to...
  12. pattiane

    Overcurrent Danfoss

    Actually I'm not using the original card of the VLT, I'm using and other one: http://ftp-dee.poliba.it:8000/Liserre/23-24%20Lezione%2007%2006%202004/IPC5manual.pdf Ive done some other measurements, the conclusion is : If a put in PWMa = alpha; PWMb and PWMc must be alpha+0.03 or...
  13. pattiane

    Overcurrent Danfoss

    Interesting remark: When I send PWM signals to the 3 legs, there's no overcurrent! But sending PWM to one leg or two legs occur the overcurrent. If anyone can explain that...
  14. pattiane

    Overcurrent Danfoss

    Hi Sed2developer, No, I haven't check the power transistors yet. I will.
  15. pattiane

    Overcurrent Danfoss

    hi sed2developer, Actaully I'm not using the VLT5000 for a motor control, but for a power control. Initially I'm trying with the dump load(active power consumer). But my problem is only a hardware problem, since there is any complex control. When I send a PWM signal to one leg of the inverter...
  16. pattiane

    Overcurrent Danfoss

    No, the dump load is a resistive load designed to dissipate the excess power generated by the generation systems when the batteries are fully charged.
  17. pattiane

    Overcurrent Danfoss

    I forget something. I tried using without the dump load.But the overcurrent is still present.
  18. pattiane

    Overcurrent Danfoss

    Hi Dick, I knew my explanation was not clear... Actually "the power feedback device" is a REVCON Unit(german brand).I feed the DC bus via the rectifier from the Danfoss. The only function of the Revcon unit is to maintain the voltage stable.The measurement done indicates 550V. I measure via...
  19. pattiane

    Overcurrent Danfoss

    Hi, I'm using a dSPACE 1104 to control a Danfoss drive VLT5000. The DC bus of the inverter(Danfoss) is fed by a power feed back unit to maintain stable the DC voltage. I put a dump load in AC side(Danfoss inverter side). And when I tried sending a PWM signal in one leg, I can see a overcurrent...

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