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Powered by Question2AnswerError: accessing blockset
http://forum.plexim.com/1425/error-accessing-blockset
Hi<br />
<br />
I am trying to open my Plecs model which was made in the blockset mode with matlab. The attached error message is popping up and Plecs blocks are not accessible.<br />
<br />
Kindly suggest how to remedy this?<br />
<br />
<br />
<br />
Thanks<br />
<br />
Snehahttp://forum.plexim.com/1425/error-accessing-blocksetThu, 19 Sep 2019 01:33:48 +0000Answered: Negative switching or conduction losses are cropped
http://forum.plexim.com/1396/negative-switching-or-conduction-losses-are-cropped?show=1398#a1398
Hello,<br />
<br />
It appears that these are not the official thermal descriptions provided by the manufacturer on their website. We would recommend that you use those models if possible.<br />
<br />
It is also not easy to fully diagnose the issue without having your circuit model that shows the error message. I suspect, however, the issue is a numerical one. For example, with the thermal description you attached for C2M0080170P, the Conduction Loss current axis has a value of 6.133300000000001e-15. You should change this to 0. Also, the datapoint at 25C and 10A is 0.8436100000000001. This should probably be truncated to 0.84361. Further, your thermal impedance coefficients have a complexity that may lead to a numerically stiff system.<br />
<br />
Let me know if this helps.<br />
<br />
Krishttp://forum.plexim.com/1396/negative-switching-or-conduction-losses-are-cropped?show=1398#a1398Fri, 13 Sep 2019 18:31:09 +0000Can we get accurate frequency sweep results for converters with a variable switching frequency using Analysis tools?
http://forum.plexim.com/1383/frequency-converters-variable-switching-frequency-analysis
<p>Hi there,</p><p>I am trying to obtain the frequency response of a closed-loop buck converter. I am using a boundary control method to regulate output voltage of the buck converter.In this case, <strong>switching frequency is varying slightly in steady state operation( sometimes 6.944 kHz and sometimes 7.352 kHz for given operating conditions)</strong>. I tried Ac sweep,impulse response analysis method as well as Mutitone analysis to obtain the frequency response from Vref to Vc.I used a value close to the switching period as the system period where ever it needed but i was unsuccessful in getting the results that i expected and mostly solutions did not even converge.</p><p>Could you please advice on how to use analysis tools for a converter with variable switching frequency to obtain the frequency response? Is there any demo model that i can follow and understand. Really appreciate your help on this. </p><p>Thanks</p><p>Dilan</p>http://forum.plexim.com/1383/frequency-converters-variable-switching-frequency-analysisWed, 11 Sep 2019 05:14:09 +0000Answered: Metal Oxide Varistor (MOV)
http://forum.plexim.com/1330/metal-oxide-varistor-mov?show=1374#a1374
Hello,<br />
<br />
The Piecewise Linear Resistor is exactly that, a set of predefined I-V pairs. But the MOV implementation in the referenced thread above allows for the calculation of time-varying, non-preset resistance values. Does that make sense?<br />
<br />
Thanks,<br />
Krishttp://forum.plexim.com/1330/metal-oxide-varistor-mov?show=1374#a1374Tue, 10 Sep 2019 04:42:38 +0000Saturable Transformer (2-Windings)
http://forum.plexim.com/1331/saturable-transformer-2-windings
Hi.<br />
<br />
I am trying to simulate the saturable transformer and I have a query related to that.<br />
<br />
There are two fields - 'Magnetizing current values' and 'Magnetizing flux values'. I need help in entering these fields. Are they modeling only the linear portion of B-H curve? How to check if it is getting saturated.<br />
<br />
Also data sheet does not provide direct current to flux values. It may have current vs voltage values. So can I get some documents that explains me to find current vs flux values.?<br />
<br />
<br />
<br />
Bhavanihttp://forum.plexim.com/1331/saturable-transformer-2-windingsWed, 28 Aug 2019 13:01:03 +0000Answered: Can V*I be used to calculate switching losses of a Limited di/dt MOSFET?
http://forum.plexim.com/1305/can-be-used-to-calculate-switching-losses-of-limited-mosfet?show=1316#a1316
Hello,<br />
<br />
Correct, we do not recommend that you use the voltage and current waveforms of the two switch components with limited turn-on and turn-off for loss calculation. The peak magnitudes of overvoltage and overcurrent waveforms are accurately calculated, but the higher order growth and decay curves in the real device's behavior are highly dependent on the external circuitry so we don't want you to assume your model corresponds to a hardware implementation. The standard MOSFET should be used for loss calculation with a thermal description and cooling circuit.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1305/can-be-used-to-calculate-switching-losses-of-limited-mosfet?show=1316#a1316Fri, 23 Aug 2019 17:58:38 +0000Answered: How to generate unipolar PWM for boost converter using C-script?
http://forum.plexim.com/1306/how-generate-unipolar-pwm-for-boost-converter-using-script?show=1314#a1314
Hello,<br />
<br />
Have you looked at the demo model included in PLECS called "Inverter with C-Script-Based PWM Modulator"? You can view and modify the C-Script based modulator for your purpose.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1306/how-generate-unipolar-pwm-for-boost-converter-using-script?show=1314#a1314Fri, 23 Aug 2019 17:45:03 +0000Answered: How to set the Rise time and Fall time of the MOSFET di/dt model
http://forum.plexim.com/1312/how-to-set-the-rise-time-and-fall-time-of-the-mosfet-di-dt-model?show=1313#a1313
Hello,<br />
<br />
The screenshots are helpful, but it is much easier to give feedback if you attach your model. Anyway, please see the help description for the "IGBT with Limited di/dt" component as there are example plots showing you what the rise and fall times are graphically. This should help you to verify that the model is correct.<br />
<br />
Thank you,<br />
<br />
Krishttp://forum.plexim.com/1312/how-to-set-the-rise-time-and-fall-time-of-the-mosfet-di-dt-model?show=1313#a1313Fri, 23 Aug 2019 17:40:55 +0000State discontinuity after switching
http://forum.plexim.com/1302/state-discontinuity-after-switching
I'm simulating half bridge resonant converter. It works fine when I use diode in rectifier circuit but as soon as I use MOSFET it shows the state discontinuity error. I tried to simulate separately a center tapped rectifier which was working fine with diode but as soon as use MOSFET it shows the same error. I'm giving complementary gate pulse to both the signal. Where is the error and what shall I do to resolve this error?http://forum.plexim.com/1302/state-discontinuity-after-switchingWed, 21 Aug 2019 13:05:04 +0000Answered: How to model the losses of MOSFET with Diode?
http://forum.plexim.com/1296/how-to-model-the-losses-of-mosfet-with-diode?show=1298#a1298
Hello,<br />
<br />
With this particular datasheet, there is limited information available as you mentioned, and we recommend you contact the manufacturer to request additional datapoints, curves, etc. To fully diagnose the issue regarding the error message, we would need to see your model and thermal description files. This might be easily fixed with a few additional datapoints in the thermal description. It might also be that the thermal cooling network is insufficient or that you are not operating the device within its normal range.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1296/how-to-model-the-losses-of-mosfet-with-diode?show=1298#a1298Tue, 20 Aug 2019 17:10:12 +0000Answered: How to specify Diode resistance and Diode forward drop in thermal modelling of MOSFET with Diode?
http://forum.plexim.com/1294/specify-diode-resistance-forward-thermal-modelling-mosfet?show=1297#a1297
Hello,<br />
<br />
This component only allows you to specify the device on-resistance in the on state (conducting in either direction). To include Vf_diode, Ron_diode, or to model current sharing during reverse conduction, you will need to use separate MOSFET and diode components.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1294/specify-diode-resistance-forward-thermal-modelling-mosfet?show=1297#a1297Tue, 20 Aug 2019 17:04:13 +0000Answered: example of config solver parameters PLECS XML-RPC with python.
http://forum.plexim.com/1277/example-config-solver-parameters-plecs-xml-rpc-with-python?show=1288#a1288
<pre class="editorCode">opts = {'ModelVars' : { 'varL' : 50e-6 }, </pre><pre class="editorCode"> 'SolverOpts' : { 'Solver' : 'discrete',</pre><pre class="editorCode"> 'StartTime' : 0,</pre><pre class="editorCode"> 'StopTime' : 0.1</pre><pre class="editorCode"> }
}</pre>http://forum.plexim.com/1277/example-config-solver-parameters-plecs-xml-rpc-with-python?show=1288#a1288Mon, 19 Aug 2019 07:35:36 +0000Answered: Fixpoint Controller Simulation
http://forum.plexim.com/1249/fixpoint-controller-simulation?show=1270#a1270
Hi,<br />
<br />
Unfortunately only DLLs using C and C++ are officially supported in PLECS. Googling gives a few option that you could try, but again this is fully experimental and not officially supported/tested by the Plexim developers.<br />
<br />
1. Implement the fixed-point control algorithm in C using the FixMath library (<a href="http://www.nongnu.org/fixmath/doc/index.html" rel="nofollow">http://www.nongnu.org/fixmath/doc/index.html</a>)<br />
2. Embed python into C, see e.g. <a href="https://docs.python.org/2/extending/embedding.html" rel="nofollow">https://docs.python.org/2/extending/embedding.html</a> or <a href="https://www6.software.ibm.com/developerworks/education/l-pythonscript/l-pythonscript-ltr.pdf" rel="nofollow">https://www6.software.ibm.com/developerworks/education/l-pythonscript/l-pythonscript-ltr.pdf</a><br />
3. It might be possible to create a dll from Python using Cython (see <a href="https://cython.org/#about" rel="nofollow">https://cython.org/#about</a> or <a href="https://docs.python.org/3/faq/windows.html#is-a-pyd-file-the-same-as-a-dll" rel="nofollow">https://docs.python.org/3/faq/windows.html#is-a-pyd-file-the-same-as-a-dll</a>)<br />
<br />
Best regards,<br />
NFhttp://forum.plexim.com/1249/fixpoint-controller-simulation?show=1270#a1270Fri, 16 Aug 2019 15:56:59 +0000Answered: How to run script file in PLECS without using MATLAB?
http://forum.plexim.com/1261/how-to-run-script-file-in-plecs-without-using-matlab?show=1263#a1263
Hello,<br />
<br />
I assume you mean PLECS Standalone when you said you only have PLECS? But anyway, we recommend the PLECS User Manual, available on our website at www.plexim.com/download/documentation, or the built-in Online Help as a resource for many questions on using the tool. In the Initialization Parameters window of the Simulation Parameters window in PLECS Standalone you can enter any valid MATLAB/Octave expression, consisting of MATLAB/Octave functions, operators, and variables. So this can directly be a code that is run to initialize variables, or you can reference by name an m file that sits in the same directory as the model. If you want to run multiple situations or start and modify a simulation or analysis, for example, there is both an internal scripting environment in PLECS Standalone, and a method for externally controlling PLECS Standalone. Both options are described in Chapter 10 "Simulation Scripts". Please let me know if you have further questions.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1261/how-to-run-script-file-in-plecs-without-using-matlab?show=1263#a1263Wed, 14 Aug 2019 17:48:07 +0000Documents for designing snubber circuits for three phase thyristor bridge rectifier
http://forum.plexim.com/1258/documents-designing-snubber-circuits-thyristor-rectifier
I am looking for any help with the design of RC snubber circuit for the three phase thyristor bridge rectifier. The thryistors (SCRs) undergo reverse recovery process during turnoff and hence they experience huge voltage spikes (or overvoltages) if snubbers are not used. Are there any design procedures available in designing the RC snubber circuits for such a rectifier configuration. <br />
<br />
Thanks in advance.<br />
<br />
Malepati Sankar.http://forum.plexim.com/1258/documents-designing-snubber-circuits-thyristor-rectifierTue, 13 Aug 2019 06:58:32 +0000Answered: What is Lrr in 'Thyristor with reverse recovery'?
http://forum.plexim.com/1243/what-is-lrr-in-thyristor-with-reverse-recovery?show=1254#a1254
Hello,<br />
<br />
Please see the reference paper for this implementation, and specifically a short discussion of the inductance on Page 3: <a href="https://cds.cern.ch/record/291468/files/cn-95-016.pdf" rel="nofollow">https://cds.cern.ch/record/291468/files/cn-95-016.pdf</a><br />
<br />
Let us know if you have further questions.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1243/what-is-lrr-in-thyristor-with-reverse-recovery?show=1254#a1254Mon, 12 Aug 2019 16:56:02 +0000Answered: How to set the parameter of the thermal resistance Rth(or Zth) between case and heat sink?
http://forum.plexim.com/1250/parameter-the-thermal-resistance-rth-between-case-heat-sink?show=1253#a1253
Hello Sara,<br />
<br />
Yes, from the image you attached, you have implemented a viable solution for defining Rth,cs. This is not necessary, but should you want to include the thermal capacitance of the case and/or heat sink you have two options. Either you will need to design a hierarchical structure of subsystems to define the thermal layers and use the Ambient Temperature component inside to connect to the nearest external layer (e.g., device sits on Case heat sink block, and via Rth,cs connected to ambient outside of subsystem, which is actually the true heat sink of the system), or directly place a Thermal Capacitor at each node in between.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1250/parameter-the-thermal-resistance-rth-between-case-heat-sink?show=1253#a1253Mon, 12 Aug 2019 16:51:29 +0000Plecs blockset is not saving the data for complete simulation in .csv file?
http://forum.plexim.com/1206/plecs-blockset-not-saving-the-data-complete-simulation-file
I am using PLecs Blockset with matalb and trying to save my results in .csv file. But the file is not loading properly and does not include the data points for complete simulation. PLease help how I can extract the waveforms from scope and edit/ modify them for my use.<br />
<br />
<br />
<br />
Thanks<br />
<br />
Snehahttp://forum.plexim.com/1206/plecs-blockset-not-saving-the-data-complete-simulation-fileThu, 25 Jul 2019 15:19:13 +0000How can I get an accurate power loss information using thermal description in case of soft switching?
http://forum.plexim.com/1184/accurate-power-information-thermal-description-switching
Hi, <br />
<br />
I working on loss modelling of PFC converter. My PFC operates in boundary conduction mode (CrCM) and the MOSFET switches on at Valley or zero valley (ZVS) of drain-source voltage. In order to achieve VS/ZVS, I used a parallel capacitance (22pF from datasheet) and reverse diode (Body diode) across the MOSFET. To calculate the power loss I am using thermal model. The problem is, at the valley point (when let's say Vds = 320V) the instantaneous voltage drop across capacitor causes a big current spike (approx. 900A) through the MOSFET. Thermal model calculates conduction power loss corresponding to this current spike too which is in order of kW. Is there any way around to get an accurate power loss during soft switching? <br />
<br />
Thanks <br />
<br />
Qurathttp://forum.plexim.com/1184/accurate-power-information-thermal-description-switchingSat, 20 Jul 2019 17:51:31 +0000Implementing Fuzzy Logic Control for an Energy Storage System
http://forum.plexim.com/1178/implementing-fuzzy-logic-control-for-energy-storage-system
Hello,<br />
<br />
I need to use fuzzy logic control for a hybrid energy storage system (battery + supercapacitor) in PLECS. I see some documents how to use fuzzy logic control for MATLAB. However I do not know how to implement fuzzy logic control for PLECS.<br />
<br />
Best regards,<br />
<br />
Murathttp://forum.plexim.com/1178/implementing-fuzzy-logic-control-for-energy-storage-systemFri, 19 Jul 2019 17:45:00 +0000Answered: MOSFET with diode. conduction loss overestimated when current is negative and MOSFET turned ON.
http://forum.plexim.com/1168/mosfet-conduction-overestimated-current-negative-mosfet?show=1169#a1169
Hello,<br />
<br />
This is a great question. If you use separate MOSFET and diode components, the current sharing (and therefore the losses) during reverse conduction of the overall device is determined by the path impedances of the MOSFET and body diode. If you have chosen not to provide on-resistance values for either device, the current will be shared equally between the diode and MOSFET.<br />
<br />
You should consider the typical timing of the switching events. Can it be assumed that the diode conducts for only a small time during the interval before the FET is gated on? Are you expecting a specific current sharing behavior if the FET is reverse-biased? Or do you want PLECS to only consider the Rds(on) characteristic in this situation? <br />
<br />
If you want the MOSFET to carry the entire current when it is gated on during third quadrant conduction, you can actually use the combined MOSFET and Diode component. I have attached a working example of this approach, which requires a little bit of explanation. The single thermal description uses Custom Tables that are called in the Conduction Loss tab's formula and are chosen based on whether the MOSFET gate signal is zero or nonzero. To easily view the example device thermal description, with this model open, go to the Window>Thermal Library Browser menu option and look for "MOSFET3rdQ_body_diode".<br />
<br />
You should also look under the mask of the MOSFET converter and see that it looks as it normally does, but in fact, each device is reimplemented as it’s own masked subsystem. Looking further under the mask of one device you will see that a gate signal tag has been added, which is used in the conduction loss equations. You will see that at each subsystem level’s mask we are passing the gate signal by reference to the next higher level. Please let me know if you have questions, but I believe this implementation can be easily replicated and modified to include your own part’s loss data.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1168/mosfet-conduction-overestimated-current-negative-mosfet?show=1169#a1169Thu, 18 Jul 2019 22:11:42 +0000Answered: How to simulate a device with known V-I Equation
http://forum.plexim.com/1142/how-to-simulate-a-device-with-known-v-i-equation?show=1160#a1160
Hello,<br />
<br />
Due to the fact that the voltage applied to the device affects the current, and the current driven through it affects the voltage drop across it, a variable-resistance by it's very nature creates an algebraic loop. This is not easily solved without taking certain steps to break such a loop. We introduced "Algebraic Components" into the PLECS library (Electrical and Mechanical components) in a recent release that can be used for exactly this type of problem. I have included a very basic model showing the design and operation of a MOV using a current source stimulus and some dummy IV curve data implemented in a 1D Lookup Table. The requirement of the Algebraic Component is that the two output signals, "v" and "i", must affect the input signal "0" by means of a direct feedthrough path. In this case, I chose to drive the "0" input signal to zero by subtracting the calculated value of voltage as provided by the lookup table from the measured voltage value in the component. You should be able to use this model as a reference and include your own custom data in the lookup table (you could also have temperature dependence via a 2D Lookup Table). I hope this helps.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/1142/how-to-simulate-a-device-with-known-v-i-equation?show=1160#a1160Wed, 17 Jul 2019 19:03:05 +0000Answered: Charging using CCCV with a buck converter
http://forum.plexim.com/915/charging-using-cccv-with-a-buck-converter?show=1136#a1136
Hi the problem is in your control<br />
<br />
you are working CC with 20A until 49.5V and the CV, the problem is that there is a current jump to 360A that cause a big voltage drop in the battery model (actually is the internal voltage drop is higher than the external voltage drop)<br />
<br />
You should release the CC lately or correct the string battery parameters.http://forum.plexim.com/915/charging-using-cccv-with-a-buck-converter?show=1136#a1136Wed, 10 Jul 2019 10:23:16 +0000Answered: transfer function problem (AC sweep analysis)
http://forum.plexim.com/1129/transfer-function-problem-ac-sweep-analysis?show=1133#a1133
<p>PLECS is running into numerical truncation problems due to your choice of parameters:</p><ul><li>large DC offset, i.e. your filter input (1330)</li><li>large time constant (2000)</li><li>very small "Rel. perturbation for Jacobian" in the "Steady-State Options" of the AC Sweep (1e-6)</li></ul><p>As a consequence, when PLECS tries to linearize the model, it gets a plain 0 for the Jacobian matrix.</p><p>If you increase the "Rel. perturbation for Jacobian" to 1e-4 (which is the default), you will get the expected result. But if you then <em>also</em> increase the filter input or the time constant by a factor of 100, you will run into the same problem again. </p>http://forum.plexim.com/1129/transfer-function-problem-ac-sweep-analysis?show=1133#a1133Wed, 10 Jul 2019 09:18:19 +0000Answered: Matlab 2013b crashes after installing PLECS
http://forum.plexim.com/1128/matlab-2013b-crashes-after-installing-plecs?show=1131#a1131
<p class="editorCode">This is due to a bug in MATLAB R2013b: MATLAB freezes when opened if it executes a "startup.m" file that adds an "info.xml" file to the search path.</p><p class="editorCode">For a detailed explanation and possible solutions, please see this <a rel="nofollow" href="https://www.plexim.com/support/solutions/1027">technical solution</a> on the Plexim web site.</p>http://forum.plexim.com/1128/matlab-2013b-crashes-after-installing-plecs?show=1131#a1131Wed, 10 Jul 2019 06:51:41 +0000Answered: Small signal analysis for 3-phase inverter
http://forum.plexim.com/37/small-signal-analysis-for-3-phase-inverter?show=1117#a1117
<p>Hi <a rel="nofollow" href="https://forum.plexim.com/user/yunpeng">yunpeng</a> generally for inverter, they are normally buck converter and you are not using contolling theory like DCDC but more like LC filter damping. I think all the answer you need are in this cookbook:</p><p><a rel="nofollow" href="https://www.amazon.com/Digital-Control-Electronics-Synthesis-Lectures/dp/1627057536">https://www.amazon.com/Digital-Control-Electronics-Synthesis-Lectures/dp/1627057536</a></p><p> </p>http://forum.plexim.com/37/small-signal-analysis-for-3-phase-inverter?show=1117#a1117Fri, 05 Jul 2019 09:03:02 +0000Answered: Interfacing Xilinx Zedboard or Kintex 7 (FPGA) with PLECS RT Box for HIL test
http://forum.plexim.com/1070/interfacing-xilinx-zedboard-kintex-fpga-with-plecs-box-test?show=1110#a1110
Hello,<br />
<br />
Plexim offers the Interface Boards listed on our website: <a href="https://www.plexim.com/products/rt_box" rel="nofollow">https://www.plexim.com/products/rt_box</a>. This list does not currently include an interface to an FPGA board.<br />
<br />
Best regards,<br />
<br />
Krishttp://forum.plexim.com/1070/interfacing-xilinx-zedboard-kintex-fpga-with-plecs-box-test?show=1110#a1110Tue, 02 Jul 2019 17:57:49 +0000Using CAN on the RT Box 1
http://forum.plexim.com/1082/using-can-on-the-rt-box-1
Hi,<br />
<br />
<br />
<br />
I'm trying to make use of the CAN interface on the RT using the digital breakout board.<br />
<br />
As soon as I check the CAN1 in the Coder options I get an error saying:<br />
<br />
"Target response 401, Error transfering <a href="http://169.xxx.x.xxx/cgi-bin/start.cgi" rel="nofollow">http://169.xxx.x.xxx/cgi-bin/start.cgi</a> - server replied: Internal Server Error<br />
<br />
Communication with realtime simulation failed."<br />
<br />
when I start the build process. This happens with an empty PLECS model and with and without any connection to the D-Sub connectors.<br />
<br />
Same happens when using the CAN Transmitter from PLECS standalone.<br />
<br />
I have also monitored the CAN interface using a CAN-2-USB adapter and did not see any sort of communication by the RT box.<br />
<br />
See attached a screenshot of the whole setup.<br />
<br />
<br />
<br />
Best regards<br />
<br />
gntjahttp://forum.plexim.com/1082/using-can-on-the-rt-box-1Wed, 26 Jun 2019 08:28:35 +0000Answered: How can be computed the switching frequency?
http://forum.plexim.com/1014/how-can-be-computed-the-switching-frequency?show=1069#a1069
<p>try this one I have try to build a F-V converter, otherwise the best is a state machine block<img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=8271784498626906327" style="height:469px; width:600px"></p>http://forum.plexim.com/1014/how-can-be-computed-the-switching-frequency?show=1069#a1069Fri, 21 Jun 2019 07:45:04 +0000Answered: How to simulate a three phase transformer with mutual inductance?
http://forum.plexim.com/932/how-simulate-three-phase-transformer-with-mutual-inductance?show=1068#a1068
<p><img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=4845976476547182391" style="height:447px; width:513px"></p><p> </p><p>Is this something useful for you? this is the Yy transformer when you look in the block</p>http://forum.plexim.com/932/how-simulate-three-phase-transformer-with-mutual-inductance?show=1068#a1068Fri, 21 Jun 2019 06:36:05 +0000Answered: Parse a PLECS file
http://forum.plexim.com/1017/parse-a-plecs-file?show=1065#a1065
Hi<br />
<br />
Im doing one to read out the parameter of initialization and use it to create a class in python for my model. what you need exactly? Otherwise I agree with oliver that is better to use the API<br />
<br />
Another useful way to use directly the change of code is adding complex probe content, like 20-30 probe signals that have the same name, but maybe is only my need :)http://forum.plexim.com/1017/parse-a-plecs-file?show=1065#a1065Fri, 21 Jun 2019 06:31:24 +0000Scope GetCursorData through XMLRPC
http://forum.plexim.com/1060/scope-getcursordata-through-xmlrpc
<p>My question is similar in spirit to:</p><p><a rel="nofollow" href="https://forum.plexim.com/673/exporting-scope-data-as-csv-using-xml-rpc?show=673#q673">https://forum.plexim.com/673/exporting-scope-data-as-csv-using-xml-rpc?show=673#q673</a></p><p>where the user wanted to use the plecs('scope', 'scopepath', 'ExportCSV', 'filename') plecs to export some scope data to CSV using python's xml rpc client.</p><p>I would like to use plecs('scope', 'scopepath', 'getcursordata', [t1, t2], 'analysis1, ...) from xmlrpc but server.plecs.scope('scopepath', 'GetCursorData', [t1, t2], 'analysis1', ... ) returns an "invalid method parameters" error. My guess is that this is another function which does not translate to xml-rpc? If that is the case is there any plan to port these "missing" functions from plecs standalone script environment to xml-rpc?</p>http://forum.plexim.com/1060/scope-getcursordata-through-xmlrpcWed, 19 Jun 2019 18:19:33 +0000Answered: Interleaving connections
http://forum.plexim.com/1024/interleaving-connections?show=1032#a1032
<p>Hi Goutham,</p><p>As given in the PLECS Help Viewer under "Connections", for drawing a branch from an existing connection, place the mouse pointer where it is desired that the branch will start. With the right mouse button or with the left mouse button while holding down the [Ctrl] key (or [command] key on Mac OS), create a branch to a new destination by dragging the crosshairs.</p><p>I'm also attaching the "PLECS Cheat Sheet" here for other PLECS shortcuts.</p><p>A solid black dot marks a connection between two wires. Two electrical wires merely overlapping on one another without a connection will not have this solid black dot, therefore a curved wire, as shown in your circuit, to mark this distinction, isn't necessary. </p><p>An example of an interleaved boost converter is given in the PLECS demo model library. Browse to Window > Demo Models, and search for "Single-Phase Battery Charger". Open the PLECS model and then double click on the AC/DC subsystem to view the attached schematic.</p><p><img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=8852781333049902338" style="height:371px; width:600px"></p><p>Best regards,<br>Manu</p><p> </p>http://forum.plexim.com/1024/interleaving-connections?show=1032#a1032Wed, 12 Jun 2019 19:24:52 +0000Answered: How much is the loss erro introduced for not considering the diode reverse recovery behavior in the thermal simulation?
http://forum.plexim.com/992/introduced-considering-reverse-recovery-behavior-simulation?show=1008#a1008
it depend strongly from the diode you use, power diode have different effect depending from the temperature, for "normal" diode the temperature variation of the reverse recovery is also a factor 100%. <br />
<br />
But I think this will not be the main cause of efficiency degradation in your power train, that means in first approximation is negligible.http://forum.plexim.com/992/introduced-considering-reverse-recovery-behavior-simulation?show=1008#a1008Thu, 06 Jun 2019 08:36:18 +0000Answered: How do I make this system run faster.
http://forum.plexim.com/977/how-do-i-make-this-system-run-faster?show=994#a994
<p>My 2 Cents:</p><ul><li>Please clean up your PLECS schematic before you submit it to get help. It increases the chance to get a quick answer. </li><li>I suspect the circuit is getting stuck in some kind of algebraic loop. (Not an expert on that.)</li><li>Why does the voltage controller have output saturation and the current controller doesn't? You always want to add output saturation.</li><li>The combination of the current reference from the voltage controller and the set current is usually done using a MIN(a,b) function in unidirectional converters, not sure what your goal is with the switch. For bidirectional converters it might however get more convoluted. </li><li>Applying those two changes worked for me.</li><li>If you plan to operate the PI controller in constant saturation, you need to think about adding an integrator anti wind-up scheme. </li></ul><p>Hope this helped.</p><p>Falk</p><p> </p>http://forum.plexim.com/977/how-do-i-make-this-system-run-faster?show=994#a994Tue, 04 Jun 2019 15:26:18 +0000Answered: How to add the Manufacture models to PLECS Library
http://forum.plexim.com/981/how-to-add-the-manufacture-models-to-plecs-library?show=982#a982
Hello,<br />
<br />
Did you add the folder containing the .xml files to the list of "Thermal description search paths" in the "Thermal" tab of the PLECS Preferences window? Note that this is not the same as the "User libraries" list in the "Libraries" tab, which is used for creating custom components.<br />
<br />
Best regards,<br />
<br />
Krishttp://forum.plexim.com/981/how-to-add-the-manufacture-models-to-plecs-library?show=982#a982Fri, 31 May 2019 22:58:57 +0000Answered: PLECS IGBT Power Losses
http://forum.plexim.com/971/plecs-igbt-power-losses?show=973#a973
Hello,<br />
<br />
It sounds like you need to do some homework on how thermal losses work, but do you have a device or data sheet you can reference? Many of the devices currently supported with PLECS loss and thermal models are listed here: <a href="https://www.plexim.com/plecs/thermal" rel="nofollow">https://www.plexim.com/plecs/thermal</a><br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/971/plecs-igbt-power-losses?show=973#a973Wed, 29 May 2019 04:17:59 +0000Answered: How to enter thermal impedance of IGBT and Diode separately in the thermal model of 'IGBT with Diode'?
http://forum.plexim.com/969/enter-thermal-impedance-diode-separately-thermal-model-diode?show=972#a972
Hello,<br />
<br />
In this case you should use separate IGBT and diode components.<br />
<br />
Regards,<br />
<br />
Krishttp://forum.plexim.com/969/enter-thermal-impedance-diode-separately-thermal-model-diode?show=972#a972Wed, 29 May 2019 04:15:55 +0000Answered: dismiss last username and change user to work with plecs software
http://forum.plexim.com/960/dismiss-last-username-change-user-work-with-plecs-software?show=961#a961
Hello,<br />
<br />
Yes, exactly.<br />
<br />
Thank you,<br />
<br />
Krishttp://forum.plexim.com/960/dismiss-last-username-change-user-work-with-plecs-software?show=961#a961Thu, 23 May 2019 14:19:50 +0000Answered: Heat Sink Simulation Error
http://forum.plexim.com/927/heat-sink-simulation-error?show=958#a958
Hello, you just need to provide a gate resistance value, e.g. 2.5 ohms.http://forum.plexim.com/927/heat-sink-simulation-error?show=958#a958Tue, 21 May 2019 17:08:52 +0000Answered: Why my simulation shows inconsistent source, state/source dependence ?
http://forum.plexim.com/942/simulation-shows-inconsistent-source-state-source-dependence?show=945#a945
Hi Manoj, <br />
<br />
The current source needs a valid return path at all times, which is not given in your circuit. <br />
<br />
The PLECS documentation states: "A current source may not be open-circuited or connected in series to an inductor or any other current source."<br />
<br />
Hope this helps.<br />
<br />
Falkhttp://forum.plexim.com/942/simulation-shows-inconsistent-source-state-source-dependence?show=945#a945Thu, 16 May 2019 08:06:49 +0000Answered: Can we use dynamic variables to represent a numerator/denominator coefficients in transfer function block ?
http://forum.plexim.com/920/variables-represent-numerator-denominator-coefficients?show=926#a926
<p>Hi Dilan,</p><p>You cannot update a variable, for example "w01" in your case, within the simulation, however you can create a dynamic transfer function by expanding it as shown in the "Help" section (see the image below) and then feeding a value calculated from the simulation to this expanded transfer function.</p><p><img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=3628199152626546579" style="height:458px; width:600px"></p><p>I have created the attached model (both Standalone and Blockset versions) for the transfer function you described. (<strong>Note that t</strong>his model contains model initialization commands that are accessible from:<br><em>PLECSStandalone: </em>The menu <strong>Simulation+SimulationParameters...+Initializations </strong><br><em>PLECS Blockset: </em>The Simulink menu <strong>File + Model Properties + Callbacks + InitFcn*</strong>)</p><p><img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=15067648052012871850" style="height:75px; width:232px"></p><p>By comparing this equation with the equation from the "Help" section, we get the following numerator and denominator coefficients</p><p>n2 =0;<br>n1=6282;<br>n0=0;<br>d2=1;<br>d1=6282;<br>d0=w01;</p><p>From these values, we can calculate the coefficients for the expanded transfer function (modeled in the "dynamic transfer fcn" subsystem) as follows:</p><p>b2=1/d2;<br>b1=d1/d2;<br>b0=d0/d2;<br>a2=n2;<br>a1=n1-n2*b1;<br>a0=n0-n2*b0;</p><p>In your case, since your "d0" is a variable obtained from the simulation, we need to calculate the coefficients "a0" and "b0" from the simulation as well. We can achieve this by replacing the "Gain" blocks corresponding to "a0" and "b0" with "Product" blocks and then calculating their values from the simulation using a "function" component. In the attached model, the "variable" port corresponds to the measured frequency, "w01".<br><br><img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=5049549421702339840" style="height:325px; width:600px"></p><p>This model can also be adapted to work with any other second order transfer function by changing the numerator and denominator coefficients under initialization parameters, as well as replacing the corresponding gain blocks in the "dynamic transfer fcn" subsystem with a product block combined with a "function" component, to accept the desired variable from the simulation, as shown above.</p><p>Regards,<br>Manu</p><p> </p>http://forum.plexim.com/920/variables-represent-numerator-denominator-coefficients?show=926#a926Fri, 10 May 2019 20:05:34 +0000Does anyone have experiences in MPPT schematics for wind turbines PMSG in PLECS?
http://forum.plexim.com/913/does-anyone-have-experiences-mppt-schematics-turbines-plecs
http://forum.plexim.com/913/does-anyone-have-experiences-mppt-schematics-turbines-plecsTue, 07 May 2019 11:22:29 +0000CCCV for a buck converter charging a lithium ion battery model
http://forum.plexim.com/905/cccv-for-buck-converter-charging-lithium-ion-battery-model
Hi,<br />
<br />
I am trying to charge the battery using cccv; however, the current seems to not drop once cv is enabled and the voltage increases more than 50V. Any suggestions of how to fix that?http://forum.plexim.com/905/cccv-for-buck-converter-charging-lithium-ion-battery-modelFri, 03 May 2019 17:42:45 +0000Snubber capacitance for IGBT error
http://forum.plexim.com/892/snubber-capacitance-for-igbt-error
<p> </p><p>I want to simulate the Snubber capacitance at both ends of IGBT to get its optimal effect on improving the switching loss efficiency of the system, but there are various errors.like Matrix is singular. Does anyone know how to solve them?</p><p><img alt="" src="http://forum.plexim.com/?qa=blob&qa_blobid=1981077171757521675" style="height:155px; width:600px"></p>http://forum.plexim.com/892/snubber-capacitance-for-igbt-errorTue, 30 Apr 2019 08:59:17 +0000Answered: Change color of mouse pointer in scope
http://forum.plexim.com/530/change-color-of-mouse-pointer-in-scope?show=885#a885
You can easily change it by changing the settings of mouse pointer.http://forum.plexim.com/530/change-color-of-mouse-pointer-in-scope?show=885#a885Sat, 27 Apr 2019 06:58:51 +0000Answered: Run multiple simulations in parallel using XML-RPC
http://forum.plexim.com/874/run-multiple-simulations-in-parallel-using-xml-rpc?show=875#a875
Hello,<br />
<br />
Unfortunately this is not possible currently.<br />
<br />
Thank you,<br />
<br />
Krishttp://forum.plexim.com/874/run-multiple-simulations-in-parallel-using-xml-rpc?show=875#a875Tue, 23 Apr 2019 15:57:06 +0000Answered: how can i calculate switching losses and efficiency?
http://forum.plexim.com/869/how-can-i-calculate-switching-losses-and-efficiency?show=870#a870
Hello,<br />
<br />
Should you have specific questions, please post them here, but a good example model to show how you can measure and calculate switching losses and efficiency (in a Scope plot, or displaying a magnitude in digits) is the PLECS demo model called "Buck Converter with Thermal Model". Please review this model and description.<br />
<br />
Best regards,<br />
<br />
Krishttp://forum.plexim.com/869/how-can-i-calculate-switching-losses-and-efficiency?show=870#a870Thu, 18 Apr 2019 16:10:35 +0000Answered: Different scope time range
http://forum.plexim.com/860/different-scope-time-range?show=865#a865
I just tried the custom time range in the Scope Parameters Window. It only allows you to set the end time as far as i can tell.<br />
<br />
I would suggest to use the Save View function.http://forum.plexim.com/860/different-scope-time-range?show=865#a865Wed, 17 Apr 2019 06:27:44 +0000Answered: simulation examples
http://forum.plexim.com/862/simulation-examples?show=864#a864
<p>Hello,</p><p>From the <em>Window</em> menu inside PLECS Standalone you can access the "Demo Models". In PLECS Blockset, I recommend you type 'plecslib' into the MATLAB command line, and from the PLECS library window that opens, there is a "Demos" block (see time 4:00 in <a rel="nofollow" href="https://www.plexim.com/support/videos/installing-blockset-win">this video</a>).</p><p>These models are then listed under the "Power Supplies" category. You can also search for a topology from within the PLECS Documentation built-in.</p><p>Regards,</p><p>Kris</p>http://forum.plexim.com/862/simulation-examples?show=864#a864Tue, 16 Apr 2019 16:16:11 +0000