Wednesday, May 20, 2020

Retrospective - feedback

It has been 7 years since we started our blog, and much before that, the off-line presence through ordinary website, traditional brick and mortar business, and via words of mouth. 

Over the 15 years of history, we have changed our business models multiple times, tried aggressive expansion, worked with partners and vendors for different strategies to sell design or sell products, cooperate with our valuable customers to develop and fine tune our products and product lines based on feedback of our customers. 

We would like to say:

Thank you! 

To our customers. To our partners. To our fans and followers! You guys rock!  

And, we would love to continue to hear from you on how we can improve ourselves to better serve you, and help you with your projects! So, please use the form on the LEFT PANEL of this blog, and send in your feedback, criticisms, ideas, proposals, topic for discussions, anything at all! 

We may have hiccups along the way due to a lot of reasons - we would like to take this opportunity to apologize on them. If you see any issues at all, please work with us and we would always try to satisfy your requirements and fix the issues for you. 

That aside, apologies - we do not want to buy pipes or buy construction materials. We also, do not have any dead or distant relatives that have a bunch of monies waiting to be inherited. We prefer hard earned monies instead. So, spammers, stay away please. If you think we are gullible, think again. 

If you like (or dislike) our services and products, and do not like to write emails, please leave a comment in our blog page below! 

If you have new product ideas, we would love to hear from you! We can work with you to market your business. 

Till then, take care and stay safe everyone! 

J&K Audio Design
21/5/2020 






Saturday, May 2, 2020

Shunt Reactor

People has been talking about the evil artifacts, such as, noises the active regulation brings, for example, those using a toroidal transformer with a motorized carbon brush, or even relays to switch to multiple taps in the transformer, to adjust the voltage when there are elevated mains voltage or brown-outs. Or, some audiophile just despises in-line or in-series regulators, saying that they choke the sound of their system, or restricts the dynamics  

So, is there a more elegant way of regulation other than the active way? Is there a way to regulate with passive components? Is there a shunt type of regulation device that can help with regulation? When it comes to transformer, or anything with a core and wire, ask us! 

Well, there is! And, it is called Shunt Reactor! 

Shunt reactor is used in industrial applications, more than home environment, where it is an absorber of reactive power to increase the efficiency of energy transmission, or to compensate (or consume) the reactive power generated by capacitive loads line capacitance - Ferranti effect). 

An inductive load consumes reactive power. A capacitive load generates reactive power. We have too MANY capacitive loads connected to our power line right now, especially with high power amplifiers that uses a lot of capacitors. Even an OPEN POWER LINE generates reactive power. 

The shunt reactor is normally connected permanently to the power line, or sometimes are switchable, or adjustable (VSR - variable shunt reactor) to cater for different daily-hour power draws or seasonal dips and peaks of power draw. 

In layman terms, shunt reactor automatically stabilize the voltage levels. minimize over-voltages. 

Usually the shunt reactor is permanently connected, or switched by a circuit-breaker (circuit-break is required ***important***). Several shunt reactors with different can be connected in parallel, or switched in and out to adapt to different power line conditions. 

A simple connection diagram of the shunt reactor is as above - across the live and neutral lines. For balance power, you will need two units of them to work in tandem. 

WARNING: It is dangerous and LETHAL mains / live AC voltages you are working on. Do it at your own risk. It is for qualified electrician only. WARNING. 

What consists of a good shunt reactor design? 

  • Air-gapped core - constant impedance, reduce loss, avoid saturation, promotes linear energizing, and minimize remanent flux in the core (flatter hysteresis B-H curve, lower inrush current) 
  • High inductance - high energy storage and resistance to changes 
  • Low DCR or thick wire gauge - quick charge and discharge
  • High grade core - minimize power loss, lower vibration and noise  

A shunt reactor may look like a transformer, but it is intended to consume or compensate reactive power, where as transformer is to convert one voltage to another, or one impedance to another. Shunt reactor has only one winding. Transformer has 2, and above for the conversion. 

Since it is switched on all the time, losses becomes important to avoid high electricity bill and heat. What are the major losses in a shunt reactor?

  • Copper losses in the winding - wire 
  • Core loss - iron core loss 
  • Eddy current losses

Therefore, it is critical to minimize losses, and have a good shunt reactor design for better reactive power compensation / voltage regulation. 

Now, are you ready to DIY a shunt reactor device and use it in your home environment? 

J&K Audio Design
2/5/2020