MEDER electronic Announces 3-D Magnetic Mapping Of Reed Sensors
Optimize components and eliminate issues that may result in faulty operations
Meder electronic Inc., a manufacturer of precise, reliable, and long-lasting miniature switches, sensors and relays, announces its 3-dimensional magnetic mapping capabilities for reed sensors. This process allows designers to more accurately place sensors and magnetic components within a system, thus eliminating any issues that may result in faulty operation.
MEDER electronic conducts 3-D magnetic mapping by incrementally measuring the reed sensor’s closure and opening points as it enters and exits the influence of a magnetic field. This information is then analyzed, allowing the user to visualize the magnetic field in three dimensions. Understanding the interacting magnetic fields allows designers to better position the magnet and sensor in the system for optimal operation. 3-D mapping also helps designers adjust the magnetic sensitivity of the reed sensor and/or the magnet’s size and strength.
The ability to know where the key operating points are is critical to sensor applications, because it allows designers to properly position the magnet and sensor well within appropriate guard bands and avoid tolerance issues. It is particularly useful in applications using more than one reed sensor or more than one magnet. For applications in which ferromagnetic material like iron, steel, nickel or cobalt are present in the area where sensing takes place, 3-D modeling becomes quite extensive and unpredictable, so magnetic mapping is the only way to know for sure where the boundaries are.
In addition to ensuring operations are well within the magnetic envelopes to avoid tolerance issues, 3D magnetic mapping helps designers optimize the sensor and magnet components, which can significantly reduce costs.
Honeywell Introduces High Sensitivity Bipolar Latching Digital Hall-Effect Sensor Ics
Honeywell has expanded its magnetic position sensor product portfolio with the SS360NT/SS360ST/SS460S High Sensitivity Bipolar Latching Digital Hall-effect Sensor Integrated Circuits. Bipolar latching magnetics make these products well-suited for accurate speed sensing and revolutions-per-minute (RPM) measurement.
For brushless DC motor manufacturers that need latching sensor ICs with reliable, consistent performance for efficient and small designs, Honeywell’s family of new High Sensitivity Latching Digital Hall-effect Sensor ICs respond to low magnetic fields and offer consistent repeatability while providing the fastest response to a change in magnetic field for enhanced motor efficiency. These sensors offer reliable switching points with high magnetic sensitivity of 30 G typical (55 G maximum) without using chopper stabilization on the Hall element, resulting in a clean output signal and the fastest latch response time in its class.
“Brushless DC motor manufacturers need sensors with high sensitivity, stable magnetics, and very fast response times to commutate the motor as efficiently as possible,” said Josh Edberg, global product marketing manager for Honeywell Sensing and Control. “By designing high-sensitivity sensor ICs without chopper stabilization, this family of sensors enables faster response times, which ultimately means more efficient motors.”
These small, sensitive, and versatile devices are operated by the magnetic field from a permanent magnet or an electromagnet. They are designed to respond to alternating North and South poles.
The SS360NT/SS360ST/SS460S can be used in a wide range of applications. Potential industrial/commercial applications include brushless dc motor commutation, flow-rate sensing for appliances, speed and RPM sensing, tachometer/counter pickup, motor and fan control and robotics control. Potential transportation applications include speed and RPM sensing, tachometer/counter pickup, motor and fan control, electronic window lifts, and convertible roof position. Potential medical applications include medical equipment that utilizes electric motors.
These devices operate over the full temperature range of -40°C to 150°C. Two package styles are available: Subminiature, SOT-23 surface mount package (SS360NT/SS360ST) supplied on tape and reel allows for compact design with automated component placement; the small, leaded, flat TO-92-style package (SS460S) allows for a compact PC board layout.
The SS360NT/SS360ST/SS460S offer a wide operating voltage range of 3 to 24 VDC, allowing for potential use in a wide range of applications. Built-in reverse voltage enhances the protection of the sensor and the circuits. Their durable design allows operation up to 150°C. Additionally, RoHS-compliant materials meet Directive 2002/95/EC.
Advanced Simulator Speeds Implementation of Direct-Drive Electric Motors in New Automotive, Marine and Powergen Applications
An electromagnetic simulation tool is speeding the commercialization of a breakthrough direct-drive technology for electric vehicles by Magnomatics. The Opera simulator has been used by Magnomatics, a company that was set up to develop new forms of magnetic power transmission, to design a novel direct drive system that integrates a permanent magnet motor with non-contact magnetic gearing.
Called the Pseudo Direct Drive, this new form of traction motor offers such an improved torque density that it can even be packaged within a vehicle's wheel. The technology has already been demonstrated on a 22-inch city-bus wheel where it generated a continuous rated torque of 4,000 Nm and speeds of up to 750 RPM, which equates to a top speed of around 80 km/hour. Magnomatics is now engaged in several other Pseudo Direct Drive design projects in areas including marine propulsion, defence vehicles and direct-drive electricity generators for wind turbines.
The design concepts behind Pseudo Direct Drive have emerged from a major design exercise by Magnomatics' design team, which evaluated thousands of design variations with the aid of automated simulation provided by Cobham Technical Services' Opera software.
Opera's finite element modeling, simulation, post-processing and optimization toolchain features a scripting language that allows users to automate their virtual design processes. Using this feature, Magnomatics has built up an extensive library of magnetic gear and motor/generator design utilities that allow its engineers to rapidly investigate new powertrain concepts. These tools provide proven and easy-to-modify design shapes for the component parts of its magnetic gearing and motor/generator systems, such as stators and rotors, as well as special post-processing routines that provide proprietary analyses of the resulting performance.
Typically, Magnomatics uses Opera scripts to evaluate hundreds of design variations, before homing in on shapes and geometries that offer the best performance. These initial design exercises are performed using Opera in a two-dimensional mode, where the simulations only take a few seconds each. Then, once the most promising design concepts have been identified, Magnomatics switches to Opera's 3D simulation mode to evaluate a small number of potential design solutions in depth.
This simulation phase is critical for Magnomatics as its major design goals, such as the need to reduce the amounts of magnetic material while optimizing torque, compete strongly against each other. Building lots of prototypes would simply take too long and be far too expensive.
During the final virtual 3D prototyping phase, Opera's speed of execution is critical, as the complete drive system has to be simulated. With motors and generators it's often possible to reduce the complexity by modeling and simulating just a segment of the radial design, as the shape is symmetrical. However, Magnomatics' magnetic gearing designs have little or no symmetry that allow the scale of the computation to be reduced.
"Opera underpins a lot of our development work," said Magnomatics' Research Director, Dr Richard Clark. "We are a highly design-centric organization and the package's design automation capability has been critical in helping us to work on so many magnetic power transmission projects."
Dr. Clark also praises Cobham's support for its customers, as the company optimized Opera for its magnetic power transmission design, by adding a feature that allows the tool to dynamically model any number of ‘moving’ air gaps in two and three dimensions, something that most other electromagnetic tools do not support. Magnomatics' magnetic gears and combined motor/gear systems typically use two air gaps for example, and its novel mCVT variable magnetic gear system requires even more.
This feature proved essential during the initial and ongoing development of Pseudo Direct Drive for commercial applications. In-wheel applications have necessitated very careful design of the air gap regions to overcome the problem of severe shock loads. When designing this feature, which allows the drive to withstand shocks of up to 20 G, Magnomatics employed Opera in conjunction with other mechanical and thermal analysis software, for a precise understanding of how its systems will perform in the real world.
Magnos Radial Pole Magnets
For exact machining of thin-walled rings on rotary tables, cylindrical grinding machines, and lathes, Schunk now offers a program of standardized magnetic chucks with radial pole pitch. Magnos radial pole plates work with electrically activated permanent magnets and are proven for hard and finish turning, as well as grinding and rough turning.
The workpiece can be machined from three sides without a changeover and since the magnetic field is active up to the outer fringe areas, extremely large workpieces can now be clamped securely and deformation-free. Due to the two-dimensional acting holding force, vibrations are greatly reduced during machining. This prevents the cutting edges of the tools from damage and improves the surface quality of the workpiece.
Depending on the individual application, three different styles of standard radial pole magnets are offered. For grinding operations, an AlNiCo single magnet system with automatic demagnetization, for turning operations, an AlNiCo double magnet system with high holding forces. The third one is for demanding volume machining during rough turning, an extra strong AlNiCo neodymium magnet system.
VAC Releases New Vacodur 49 Alloy
Vacuumschmelze GmbH & Co. KG (Hanau) has released a new alloy, Vacodur 49 has been developed for high-performance motors and generators. The new alloy features a high saturation level of 2.35 T, and complies with the international ASTM A801 Alloy Type 1 standard. The magnetic and mechanical properties of the alloy can be optimized for specific applications by adjusting the heat treatment appropriately.
The magnetic and mechanical properties of Vacodur 49 make it well suited for both stator and rotor assemblies. While its magnetic properties can be optimized for use in stator applications, yield points of up to 400 MPa can be achieved for rotor assemblies, outperforming the magnetic and mechanical properties of classic electrical steel.
The first use of the new material is in a permanent-magnet synchronous motor produced by AMK. In this design, the replacement of conventional electrical steel with Vacodur 49 has enabled the torque to be boosted to 51 Nm, an improvement of 40 percent.
AVX Develops New Lmax Series Inductors for Consumer and Industrial Power Applications
AVX Corp. has expanded its line of thin film, multi-layer organic (MLO), and broadband wire-wound conical inductors to include a new series of shielded and non-shielded SMD power inductors. Designated the Lmax series, these inductors feature a wide inductance range, low DC resistance, and the high current values necessary for industrial applications. The RoHS-compliant inductor series is suited for a broad range of consumer and industrial power applications, including test and measurement and industrial process control. They are also specified for use in DC/DC converters, switching regulated power supplies, mobile phones, and computers, as well as other peripheral and telecommunications equipment.
“Developed in response to customer requests for inductors with an even broader current range, the Lmax series inductors significantly expand the types of applications into which customers can integrate our technology,” said Gregg Elliott, product manager at AVX. “Our new Lmax series also provides design engineers with greater flexibility when designing both fixed and portable devices.”
Lmax Series power inductors are currently in production, and samples are available by request.
New Magnetic Field Coil from Teseq Generates Fields Up To 1200 A/m
Teseq Inc., a developer and provider of instrumentation and systems for EMC emission and immunity testing, offers a new magnetic field coil that generates fields up to 1200 A/m during magnetic field testing. The INA 703 is designed for testing to IEC 61000-4-8 (supply frequency magnetic fields), IEC 61000-4-9 (pulsed magnetic fields) and IEC 61000-4-10 (oscillatory magnetic fields) standards. It is well suited for medical equipment, military, avionics, aerospace and industry applications.
By using a multi-turn (37 turn) configuration, the INA 703 is able to generate higher field levels of up to 1000 A/m using a programmable power source rated for >/- 30 A like the ProfLine Conducted Immunity Test Systems. This enables testing with a current THD (total harmonic distortion) of <8 percent, as required by IEC 61000-4-8, that can only be met with a low distortion sine wave from a programmable AC source.
Another advantage of using a programmable power source is that various supply frequencies can be tested, not only 50 Hz and 60 Hz as requested by IEC 61000-4-8, but also DC and 16.7 Hz as required by some railway standards (EN 50121-4). Together with a TESEQ NSG 1007 source, INA 703 is able to generate fields with frequencies from DC to 400 Hz in 0.1 Hz resolution steps.
Taps at turns one and five provide increased accuracy when generating low amplitude fields. The required coil drive voltage is increased by reducing the turns ratio of the coil. This establishes a suitable input voltage range that allows good regulation of the test level amplitude. The tap off at one turn is primarily used for testing to IEC 61000-4-9 and IEC 61000-4-10, since both standards only require a single turn coil.
For testing to IEC 61000-4-9, the INA 703 can be used with any classic combination wave generator, including Teseq's NSG 3040 or NSG 3060 along with the INA 752 pulse wave shape adapter.
When connected to an appropriate slow oscillatory wave generator, the INA 703 enables testing to IEC 61000-4-10.
The INA 703 is also well suited for use with MFO 6501 or 6502 current sources and Teseq's NSG 3000 series generators to generate mains frequency fields up to 120 A/m continuously and short term (three seconds), both at 50 Hz and 60 Hz.
With its U-shaped rigid aluminum base and wheels, the INA 703 is quickly positioned next to or around the EUT. The coil size is 1 by 1 m and has a homogeneous field volume of 60 by 60 by 50 cm.
The INA 703 has a maximum continuous supply frequency current of 10 A, a maximum short term supply frequency current of 35 A for three seconds, a maximum continuous supply frequency field strength of 330 A/m and a maximum short term supply frequency field strength of 1100 A/m for three seconds. The unit has a maximum pulsed current of 1500 A (8/20 µs wave) and a maximum pulsed field strength of 1200 A/m.
Rotary Position Sensor Ensures Accurate Measurement at Very High Rotation Speeds
ams, a designer and manufacturer of high performance analog ICs for consumer & communications, industry & medical and automotive applications, has launched the AS5132, a magnetic rotary position sensor IC offering accurate angular measurement even at very high rotation speeds.
The AS5132 is a system-on-chip, combining integrated Hall elements, an analog front end and digital signal processing in a single device. It is particularly well suited to industrial and automotive brushless DC (BLDC) motors, where it offers designers a small, robust and easily assembled position sensing solution. It is highly resistant to interference from stray magnetic fields.
The new device improves on previous generations of magnetic encoder by dynamically compensating for angle errors attributable to propagation delay, which are most noticeable at high speeds. Error compensation is achieved through integrated pre-commutation functions. These are easy to configure in the AS5132, and do not require external software routines to be executed, therefore unburdening host microcontrollers or electronic control units (ECUs). The configuration can be changed while the device is operating, in response to changes in operating conditions such as variations in rotation speed.
In addition, the advanced signal-processing circuitry in the AS5132 gives it an improved propagation delay figure of <22 μs, which means that even before pre-commutation is implemented the angle error is small.
In combination, the small propagation delay and advanced pre-commutation deliver an accurate angle measurement even in motors rotating at speeds up to 80,000rpm: angle measurements are accurate to within ±3° (maximum). This enables BLDC motor manufacturers to achieve high and constant levels of torque even in high-speed applications over the whole dynamic range.
When paired with a simple two-pole magnet, the AS5132 provides absolute angle measurement at a resolution of 8.5 bits, or 360 positions per revolution. This measurement is available as a serial
output and as a pulse width modulated (PWM) signal.
An additional U,V,W output can be used for block commutation in a BLDC motor; alternatively an incremental signal (ABI) is available. In addition to the angle information, the strength of the magnetic field is represented as a 5-bit value. The zero position can be set by software on the production line. This simplifies assembly, as the magnet does not need to be precisely aligned with a fixed starting position.
The AS5132 is suitable for contactless rotary position sensing, rotary switches (human machine interface), AC/DC motor position control and BLDC motor position control in automotive applications such as pump BLDC motors (stop-start system) and steering column BLDC motors. The AS5132 is also particularly well suited to position sensing in double-clutch BLDC motors.
In volume production now, the price for the AS5132 rotary position sensor is $3.27 in 1000-piece quantities.