Note that polarity dots were added to your inductors after you created the spice command. A couple things to remember about transformers and spice in general. Using the saturable inductor model in ltspice, a magnetic amplifier can be simulated in a voltage regulation circuit. There are three ways to set a current through an inductor. Linear technology releases ltspice iv on native mac os x. You can use inductor part from breakout library and modify associated model to include il1 and il2 parameters. Included in the download of ltspice are macromodels for a majority of analog devices switching regulators, amplifiers, as well as a library of devices for general circuit simulati. Pcb fluxgate current sensor with saturable inductor. You can also use magnetic core with winding to model an inductor.
This paper explains, in depth, how to create spice models for the most important and pervasive element in power electronics, that of the transformer and its accompanying saturable core. Saturable inductor performance is very predict able with relatively low jitter. Building and customizing simscape electrical specialized power systems models introduction. Sparameter, equivalent circuit model, spice model, dc bias model, dc superimposition model. A simulation model for the saturable reactor, an electromagnetic devices widely used as a protective element for the thyristor circuit, is presented. Every loop containing just a source and inductor such as a transformer primary circuit must contain some resistance, however small. Model libraries for linear technology ltspice switchercad.
Hc coercive force, br remnant flux density, and bs saturation flux density, and the mechanical dimensions of the core. On the source i have selected 10 volt amplitude with a 0 degree offset. Using ltspice to simulate the switching of an inductor as per attached. The presence of a magnetic core drastically alters the behavior of the coil by increasing the magnetic flux and confining most of the flux to the core. Coilcraft sparameters and spice models are used in nuhertz technology filter synthesis and. Introduction linear induction accelerators lias produce intense, high energy, pulsed electron beams for use in many applications. It can happen, however, that you need to interface your own model with the standard models provided in the simscape electrical specialized power systems library. Although it is possible to make a dedicated subcircuit for a specific transformer, ltspice preferred method is to define a separate inductor for. Return to ltspice annotated and expanded help commentary, explanations and examples. How do i model a saturable inductor using a magnetic core and. Ideally, the power in the primary will be delivered to the secondary 100%.
Stack an inductor and a voltagecontrolled voltage source which has two inputs. Simple steps for simulating transformers analog devices. To make it saturate, i have to use the magnetic core and coreless coil, which is fine. I would like to simulate a transformer with a defined saturation level, slope, and hysterisis, but seems like im going about it the wrong way. Ltspice enables you to model switching regulators and electrical circuits, as well as run testing simulations before actually building the electronic components. Ltspice solves for the magnetic fields in the core and gap under the assumption of uniform cross sectional area and thin or uniformly distributed gap. I was designing a simple cmos timer circuit around a 555 chip this evening. Most inductors specify inductance values at minimum current and maximum current, and then the inductance essentially drops to. The tvcl is circuit simulation model that reproduce the characteristics of tdk electric components in circuit simulators. Pspice model library includes parameterized models such as bjts, jfets, mosfets, igbts, scrs, discretes, operational amplifiers, optocouplers, regulators, and pwm controllers from various ic vendors. Simscape electrical specialized power systems provides a wide collection of models.
Osborne has been involved in a wide variety of saturable reactor design projects over the years. Ac coils are wound on the two outside legs and the dc control winding is wound on the center leg. Im trying to create a variable inductance in spice, specifically in ni multisim. November 8 1993 abstract the nonideal inductor exhibits both resonance and nonlinear current characteristics. This approach has a distinct disadvantage of disturbing hysteresis effects due to the absence of ac flux in the cores center leg. Jul 27, 2014 create a basic dc circuit with a current dependent voltage and current source. Jan 04, 2012 simple model of transformer using ltspice 1. This is the most common saturable reactor element configuration. Mutual inductance and transformer circuits with ltspice iv university of evansville july 27, 2009 in addition to ltspice iv, this tutorial assumes that you have installed the university of evansville simulation library for.
The purpose of this thesis is to present research on magnetic amplifiers and to discuss how magnetic amplifiers are useful in voltage regulation applications. A saturable reactor in electrical engineering is a special form of inductor where the magnetic core can be deliberately saturated by a direct electric current in a control winding. The tvcl is simulation model that reproduce the characteristics of tdk electronic components in circuit simulators. The loading inductor really just corrects power factor, and bringing voltage and current into phase at resonance. Magnetics designer is an option to intusofts icap4 analog and mixedsignal spice simulation tool suite. Transformer modeling and design for leakage control shi ping hsu, r.
A cross sectional area, lm magnetic length, lg length of gap and n number of turns. Trying to simulate saturable coupled inductors transformers in ltspice for some current sensing project, but seems like i cant couple arbitrary inductors. Around the spice kernel lot of people have programmed shells and programs for simple and intuitive usage and so you can find lot of software offers on the market. Place components for all fixed resistors and the capacitor. This would allow you to have an inductor which was a constant vale from zero to x2 amps. Using a behavioural currentvoltage component bi and bv. It does replace missing length by simulating an antenna. Saturablecore spice models boost intusofts magnetics. Saturable reactor inductors osborne saturable reactors are designed to provide a variable output voltage through the use of variable impedance connected in series with a constant impedance load.
I believe i have found a work around for you, that will allow you to continue using the latest versions of ltspice xvii. Ltspice insists in showing a negative current which contradicts the sense of the one through l2. Simulating the 555 ic with ltspice embedded components and. We will rotate ls to get a better look for our transformer. The inductor s current is referred to by the keyword x in the expression. I would think there would be an inductor type component somewhere in ltspice which has dialog entries for inductance at current zero amps, then inductance at current x2 amps, then inductance at current x3 amps. Beginning with a background in magnetics and magnetic properties, this thesis outlines the importance of the bh curve and explains how to simulate the bh curve of a saturable inductor using ltspice. What im trying to do is create a saturable inductor. Ltspice iv is a high performance spice iii simulator, schematic capture and waveform viewer with enhancements and models for easing the simulation of switching regulators. Right click on l1 and change it to lp and repeat same process for l2. In this case inductance value would be governed by magnetic core characteristics, which will. Change the values to those shown on the coilcraft spice model document for the inductor being modeled. Create variable inductance in spice physics forums.
Modeling nonideal inductors in spice martin ohara technical manager, newport components, u. Harvey morehouse is a contractorconsultant with many years of experience using circuit analysis programs. Ltspice iv is a high performance spice iii simulator, schematic capture and waveform viewer with enhancements and models for easing the simulation of switching. This will require ltspice to use the more cumbersome thevenin equivalent of the inductor during transient analysis. Osborne saturable reactors are designed to provide a variable output voltage through the use of variable impedance connected in series with a constant impedance load. So this is a bh loop that has history so sand saturation and ltspice requires parameters entered for the saturation flux density b sub s shown here. The inductors current is referred to by the keyword x in the expression. Unmount the volume by rightclicking also known as controlclicking or secondaryclicking the volume and selecting eject ltspice installation. Building and customizing simscape electrical specialized. Each frequencydependent element rvar1, rvar2, lvar is modeled in ltspice using the glaplace g or g2 component.
Each saturable reactors impedance is determined by the application of dc power to a control winding. Spice model of coupled inductor electrical engineering. The inductor is modeled with the core property parameters. However nothing in the help files documents any meaning for this parameter.
I think my problem is how to define the nonlinear inductor in lt spice, i can not find any example from the website, some are just part of the model, so i do not know how to put them in my model, sorry for not understanding lt spice. I need an inductor that changes its inductance with current. From zero to 120 v rms the inductor has a constant inductance, l 2 h. Do you know of something better suited for this task and still free, as it is pure hobby.
According to this brief thread on the ltspice mailing list, the peak current parameter does not affect the simulation and is only provided as a reference for the user. Arbitrary saturable coupled inductors in ltspice eevblog. Circuits may contain resistors, capacitors, inductors, mutual inductors. Here is the spice code for a saturable core just in case the link goes down here is an included picture of the model this is a graph of a modeled core. In this edition material that is specific to macspice, such as this paragraph.
And every isolated loop, such as a transformer secondary connected to a load, must have a path to ground, however large its resistance may be. How do i set an initial current through an inductor. Sparameter, equivalent circuit model, spice model as well as simulator libraries are offered. How to create a transformer using ltspice creating web pages in. Hello, anybody know how to do a saturable inductor in ltspice. Spicesimulation using ltspice iv reverse engineering. It might be the heart beat for a new digital volume control i have been thinking about. Ltspice mac osx ac analysis for phasor quantities youtube. From experimenting, setting a value here adds ipkvalue to the inductors card in the netlist. Hi, mral, thank you for your kind help, the model can work well for inductor saturation modeling, you are right that the tanh and arctan have some differences, and i tuned the parameters to make the simulated results match the measurement results because i use the arctan function. Step 2 right click on lp and l2s to open inductor properties window. This circuit is constructed and tested using three different types of magnetic materials for the magnetic amplifier. We will design a step down transformer using ltspice with 5. Discussed in this paper are the saturable inductor model and results obtained with the stage compression model.
I have been trying to model a saturable inductor so as to make a magnetic pulse compression circuit, but have been coming up against a number of barriers. Place a glaplace component for each variable resistor and inductor element typically rvar1, rvar2, and lvar. Implementing models in lt spice rf chip inductors, power. Mutual inductance and transformer circuits with ltspice iv. Ltspice simulating the switching of an inductor all about. Instructions for creating the model schematic in ltspice. His primary activities are in reliability, safety, testability and circuit analysis. To download ltspice click here for windows user and for mac user click here. Op of the circuit with inductors shorted and capacitors opened. Gardena, ca december 27, 2005 intusoft announced today the addition of several saturablecore magnetic spice models and new core materials to its inductive design and synthesis product, magnetics designer. From experimenting, setting a value here adds ipkvalue to the inductor s card in the netlist. Unless of course we are talking about heat radiation. Sep, 2014 showing how to graph phasor quantities for ltspice on macosx, on a rlc parallel network. Arbitrary saturable coupled inductors in ltspice page 1.
Draft an inductor for each transformer winding couple them using a single mutual inductance k statement via a spice directive. Ltspice is a linear technology version of spice and cant use directly the simulation model i got from on semi. Optional addon modules let you boost the flexibility and power of psim. This video shows how to download, install, configure and start working with ltspice on a mac. One is a behavioral inductance specified with an expression for the flux. Variable inductor in ltspice showing 112 of 12 messages. Does ltspice peak current for inductors do anything. The ltspice saturating inductor model introduction and power. Although it is very possible to make a dedicated subcircuit for a specific transformer, the preferred method of making a generic transformer when drafting a simulation schematic is to simply place a separate inductor for each separate transformer winding and then couple them all together magnetically via a single mutual inductance k statement placed as a spice directive on the schematic. Design inductor having a given inductance l, which carries worstcase current imax without saturating, and which has a given winding resistance r, or, equivalently, exhibits a worstcase copper loss of. Instructions for installing ltspice on mac osx the instructions below are for installing the windows version of ltspice on mac. Chapter 14 inductor design university of colorado boulder.
Excitation using a saturable inductor at 60 khz has been used and 2 a peakpeak value of the excitation current was reached. Jan 18, 2015 using ltspice to simulate the switching of an inductor as per attached. The prototype has been tested over a 2 a current range with sensitivity 28 va at 60 khz. Here is the simple approach to simulate a transformer in ltspice iv. Simulating the 555 ic with ltspice ron fredericks writes.
There are two forms of nonlinear inductors available in ltspice. Instead of 100u use the following to set the inductor current to 1a. Ltspice simulating the switching of an inductor all. Using ltspice on a mac to create a circuit with a transformer.
How do i model a saturable inductor using a magnetic core. In the following sections, a simple saturable inductance and a nonlinear resistance serve as examples. And here is the reference for the paper the article was based on. I took a bh loop of the core i want to use, input points into the data for the magnetic core, then i the appropriate number of turns on my coreless coil. Ltspice kann, via wine, auch unter linux eingesetzt werden.
Ltspice is node unlimited, incredibly easy to learn and can be used to simulate most of the analogue components from linear technology as well as discrete and passive components. Saturable reactor model a saturable reactor is a magnetic circuit element consisting of a single coil wound around a magnetic core. This decreases inductive reactance and allows increased flow of the alternating current. In addition, saturable inductors may be used in veryhigh power systems. It surprises me that ltspice does not include even a rudimentary modeling of real world inductor saturation, given that switchercad essentially revolves around the use of inductors in almost every switching supply model. Tvcl tdk virtual component library design support tdk. The spicelike component models help you obtain accurate results for nonlinear designs, while the advanced simulation capabilities allow you to test a circuits functionality. Sep 14, 2012 im trying to create a variable inductance in spice, specifically in ni multisim. Draft an inductor for each transformer winding couple them using a single mutual. Depending on the inductor series, the advanced spice models may include a variable inductor element, variable series resistance rvar1 to model skin effect, a resistor element in series with the parallel capacitance r1 to limit impedance at resonance, and a variable parallel resistance rvar2 to model frequencydependent low power core losses.
By default, ltspice will supply losses to inductors to aid smps transient analysis. Spice model of a transformer that saturates with a model of an ideal transformer and an inductor that saturates. Spice is a generalpurpose circuit simulation program for nonlinear dc. Know more about sparameters and spice models coilcraft. Most of the available programs are excellent, but huge and expensive and so we have to say thank you to linear technologies. Spice models, pspice models, simulation models, and sparameter files for coilcraft chip inductors, air core inductors inductor finders power rf. Saturable transformer model simplified spice behavioral model bee technologies inc.
We use this approach since the mac version of ltspice is not user friendly and some features are even missing. Getting started with ltspice for mac woolsey workshop. I transformer models ii saturable reactor model iii how the core model works iv calculating core parameters v using and testing the core. Ltspice mac osx create a circuit with dependent sources youtube. Magnetic amplifier technology involves unique techniques that can be tailored to match the fit, form, and function of your application. This decreases inductive reactance and allows increased flow of the alternating current ac. Lets assume there is a 10mh inductor with its part attribute defined as l3, and we want to set an initial condition of 1ma across it. Trying to simulate saturable coupled inductorstransformers in ltspice for some current sensing project, but seems like i cant couple arbitrary. In this case inductance value would be governed by magnetic core characteristics, which will also show inductance as function of current. Consider an inductor of 2 henries designed to operate at a nominal voltage, vnom 120 v rms, and a nominal frequency, fnom 60 hz. Install winebottler this is a software used to run some windows softwares on mac without having a. You model a coupled inductor in spice and other simulators by using a component called k. Magnetic amplifiers for voltage regulation applications. A saturable inductor design is easily scaled from a small prototype to applica tion in a highpower system.
Ltspice uses proprietary circuit simulation technology to simulate this physical inductor without any internal nodes. Analysis of currentcontrolled inductors by new spice. I understand that the emitter current q2, at the moment it is turned on, should be positive starting from 0 ma. K1 l1 l2 l3 1 the last entry in the k statement is the coupling coefficient, which can vary between 0 and 1, where 1 represents no leaka. Simulate complex power control systems choose from our tried and true motor drive systems or customize one you can trust. Once saturated, the inductance of the saturable reactor drops dramatically.
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