Power Electronics (Page 2)

Power Controls, Supplies, Drives.

Here are power supply, inverter, drives, chargers and high current equipment diagrams and links. There are Mosfet and Thyristor circuits too.

Power Electronics Section

Power Supplies, Inverters, UPS, Chargers, Electro Plating, Precision Welding-erosion, Coating Metals and many other Processes are made of high current circuits. Even in measurement of parameters like Micro-Ohm high currents are involved. Electronic Circuits are required in such products to give control to time, current, frequency and voltage in order to accomplish with the required precision a process or job.

Power Electronics Section - delabs
In any power equipment, efficiency and reduction of bulk is crucial so SMPS and high frequency control is an important part of this domain. These products also generate EMI-RFI. Product Safety Study is also vital.

The Power Circuits Section has been updated.

Wireless Charging is a Reality today, it was first conceived by me in the 90s. The first page published related to that in my netscape site.

This was conceived to get rid of cables for data and power on my desktop. I felt if we use Optics for Data and Wireless Ferrite Contact Plates to transfer power, there would be no wires at all on the desk. I even experimented with RS232 Serial Port and Ferrite Slices below thin Acrylic Plastic Sheet, it worked.

I did not patent any of my concepts, but it is offered to all humanity as an Open Design, like all my other work.

Here is a planar transformer which has PCB tracks for winding. This show that there is more scope of innovation in such ferrite transformers for short range wireless power.

PC User Interface and Wireless Power

Objects kept on a electromagnetic table must be able to draw energy from that. A Notebook or tablet can be just placed on this table to get charged.

The optic ball-less mouse is a great step in mice-tech user-interface. This mouse consumes more power, for a wireless mouse a capacitive sensor matrix based sensing may be better.

Touch Screen on PC is not common place. A combination of Touch screen and Mouse is excellent for all age-groups. Large monitors can have at least two inches of touch screen area at bottom.

Laptops, LCD Monitors make UPS (Uninterrupted Power Supply) last longer and it reduces electricity costs.

Wireless Power for Wireless Peripherals

Wireless Mouse with capacitive sensors may consume less power, no batteries works on a Supercap, Connector-less ferrite dock for recharging

Wireless mouse rechargeable battery can recharge while moving on the Mouse Pad made of Ferrite/Ceramic 1? Sq with Power Hot Spots every 3?

Flexible Ferrite, Silicone & Ferrite based Solid emulsion. Can be made as computer table mats to charge the supercaps of peripherals.

The Energy Efficient Wireless Peripherals can just be placed on this mat to draw the power without wires. Wireless power and Wireless Data.

Usability and Ergonomics Review
Aggregated Notes from 2008-12

Usability and Ergonomics of Electronic Consumer Equipment, product risks and safety are best studied with very old and very young people.

Optical Rotary Encoders, Magnetic/Eddy/Capacitive/Hall Effect based Non-Contact Joysticks, Makes Human An analog Interface with Digital Output.

For the people who type with two fingers; A Circular Keyboard is right. A Capacitive Touch Gesture Pad can replace the Mouse. Health & Ergo.

Personal Computers, Netbooks, Portable Communicating Devices, Remote Controls are where Usability Issues abound, and can be studied/remedied

delabs – 2009

Make the desktop architecture like laptop with regards to Power Electronics. I think now RAM’s consume lower power. So every Desktop can come with a Li-ion Backpack based on some standard. 10Ahr 12V Rechargeable Battery. The entire Motherboard works on the 12V DC supply that uses Float Charging from mains.

Power Electronics & Solar Energy

The supply to computer is always derived from battery, the battery being constantly replenished. The charger also supplies power to computer board over the battery itself. Many lighting/inverter systems use this. The SMPS now is only a intelligent charger. Other voltage levels with DC/DC converters from that 12V.

Desktop Power Supply Immunity

Advantage –

1 – A user can easily upgrade the 12 V bus, another 12 V battery with smart charger; gives a boost of backup time. Probably intelligent batteries can come with built in float chargers, so that they can they can be bussed to form a 12v Tiny power grid for home which includes solar cells.

2 – When just the backpack is used, power fails. Harddisk, Monitor etc. sent to standby, low power mode. CPU then goes to quiescent state. The RAM keeps all data intact but goes to a low power mode. Alternatively quickly write a RAM image on a Flash Layer Built over RAM.

This makes the PC Impervious to Power Supply or UPS or other problems. Moves the desktop system to a 12 V standard. Drives desktop PC development to more Power Efficient designs.

Switching Supplies and SMPS

Easy integration into automobiles, bus, etc which have DC grid. Remote areas where no power is there. This will ensure desktops have a role in the future.

The charger SMPS has 1A charging current for Battery and 3A max for Computer. Total 4A max. A SuperCap can be added parallel to the Battery for Extra Inertia.

When power fails, in few seconds the system goes to standby. No program need to be closed. When power is restored they system comes up with windows and programs in the same positions of the last frozen state.

When a UPS is used, the system does not go down at all. The UPS just consists of a 10A Charger and a 12V 20AHr Battery. If the house has a 24V DC bus which is battery supported too. Then this can be used. As 24V is being developed as a new standard for internal power distribution. EMerge Alliance. The PCs also can move to this manageable and safe standard for homes.

delabs – 2010

The LDS8711 is a fixed frequency current mode boost converter with internal rectifier and cycle-by- cycle switch current limit specifically designed to drive a string of up to 10 White LEDs.

Constant LED Brightness and LDS8711

Aa Switching Converter Chip with hardly any external components driving a HB LED chain. HB – High Brightness LED. This IC is from IXYS Power Devices.

High efficiency boost converter with the input voltage range from 2.7 to 5.5 V . Drives one LED string with 10 LEDs in series up to 32 mA.

  • 250 mV current sense voltage
  • No external Schottky Required
  • 0.7 MHz Switching Frequency
  • Efficiency greater than 83%
  • PWM LED Brightness Control
  • Low Shutdown Current (<1µA)

LED Current Setting – The maximum current value in the LED string may be factory preset in the range from 10 to 30mAin 0.125mA steps, or set by Smart OneWire interface in the range from 0.125to 32 mA.The average LED string current that determines LED brightness may be controlled applying PWM signal to the EN/PWM pin.

This Chip from TI is simple to integrate into your designs and this solution is good for production of lighting gadgets, here a consistent quality and predictable performance is easily obtained.

TPS61042 30-V, 500-mA Switch Boost Converter in QFN-8 for White LED Applications

LED-driver application that drives four LEDs with 20 mA of forward current and operates from an input voltage range of 1.8 to 6.0 V.

LED Drive using TPS61042

 

The entire circuit consists of the control IC, two small ceramic caps, an inductor, a diode, and a current sense resistor. The primary power-supply functions and the secondary features such as load disconnect, overvoltage protection, and PWM dimming have been implemented with a control IC and five small surface-mount passive components.

LED-driver considerations By Michael Day

Drives LEDs with a regulated output voltage or current (up to 120mA) from an unregulated input supply (2.7V to 5.3V). These are complete DC-DC converters requiring only four small ceramic capacitors and no inductors. 200mV Current-Sense Threshold Reduces Power Loss.

MAX1910 White LED Charge Pumps – Maxim IC

MAX1910 White LED Charge Pumps - Maxim IC

1.5x/2x High-Efficiency White LED Charge Pumps

Some Features

  • High-Efficiency 1.5x/2x Charge Pumps
  • Low Input Ripple with 750kHz Operation
  • Up to 120mA Output Current
  • 1µA Shutdown Current

The MOC303XM and MOC304XM devices consist of a AlGaAs infrared emitting diode optically coupled to a monolithic silicon detector performing the function of a zero voltage crossing bilateral triac driver. MOC3041

They are designed for use with a triac in the interface of logic systems to equipment powered from 115 VAC lines such as teletypewriters, CTRs, solid-state relays, industrial controls, printers, motors, solenoids and consumer appliances, etc.

  • Simplifies logic control of 115 VAC power
  • Zero voltage crossing
  • dv/dt of 2000 V/µs typical, 1000 V/µs guaranteed

Motorola used to make these then it was Infineon Technologies now Isocom also makes it

MOC3041 Zero Crossing Triac Output, 6 Pin

See the original Motorola Application below.

MOC3041 Zero Crossing Triac Output

Ananth –

These were used by me to make solid state relays. Look at the circuits here Power Electronics Circuits. The were used to control Heaters from DC control signal from a Proportional Temperature Controller. The Magnetic Contactors can be avoided for lower powers. At higher powers SCR banks become a bit expensive. The SSR has no mechanical wear and tear but heat up at high currents. So if we overrate by 5 Times then it is an excellent solution for lower power controls upto 5 Kilo Watts. The cycle time of Contactors must be 20-60 Seconds to make it last long. In a SSR a one second cycle time is possible as 10-20mS is the switching speed due to zero crossing.

STMicroelectronics was created in 1987 by the merger of SGS Microelettronica of Italy and Thomson Semiconducteurs of France. It is well know to engineers for very reliable and robust Power Devices and Integrated Circuits from Analog and Mixed-Power Signal to Embedded Devices.

STMicroelectronics – Industrial and Automotive Semiconductors

Segments include semiconductors for industrial applications, MEMS (Micro-Electro-Mechanical Systems), Sensors and chips for wireless and mobile applications. IC Interface and Management Solutions that are part of computing and embedded Systems.

  • Transistors, Analog & Mixed Signal ICs
  • EMI Filtering & Conditioning
  • Automotive Devices and Systems.
  • Microcontrollers, ARM, ASIC
  • Power Devices and Motor Control
  • Thyristors & ACSwitches and Motor Control

EVAL6235PD demonstration board

EVAL6235PD demonstration board

Fully integrated DMOS three-phase brushless DC motor driver. Used in conjunction with the EVALPRACTISPIN interface board and practiSPIN software, the board provides an evaluation platform to test the features of the L6235 device. In particular, the board provides a means to evaluate the power dissipation performance of the IC in the PowerSO package.