Akash – Connected Street Light


AKASH – Connected Smart Outdoor Lighting Family

Introduction

Akash is a family of smart outdoor lighting solutions. It boasts of smart, patent pending, energy based dimming algorithm, which ensures battery’s depth of discharge within safe limits to maximizing battery life and delivering light output for the intended duration. It implements MPPT charge controller to extract maximum power from solar panel as well as constant current LED driver. It implements features like communication interfaces and multiple sensor interfaces etc., for remote control and monitor for optimized usage. Akash – has products which are solar only, Grid only and hybrid (Solar + Grid)

Features

MPPT and Configurable Battery Chemistry Charging

Solar and Hybrid versions of Akash implement MPPT charger to harness maximum energy from the sun. It is true hybrid charger with Solar priority. We extract only the differential current from the AC grid unlike other systems. It is implemented as a buck converter.

LED Dimming driver

Akash implements a boost converter as a constant current LED driver. It is controlled by a microcontroller in a tight current loop. Target current is set by the present operating mode i.e., Timed Mode, Sensor Mode, Communication Mode. LED driver implements soft start and soft off for turn on and turn off for controlled transients.  

On Board Diagnostics

Akash Lighting controllers implement a robust on-board diagnostics to monitor the performance, and maintenance needs enabling proactive maintenance. Following diagnostics common for Solar and AC versions of the product.:

  • LED Open
  • LED short

Following diagnostics are only for Solar and Hybrid versions

  • Battery Diagnostics
    • Battery Full
    • Battery Low
    • Battery Empty

This information is shared with the control / command center for proactive maintenance via the communication interface.

Communication Interface

Akash is radio and protocol agnostic and the radio card is an add on to the lighting control. Provision for appropriate communication, power and control interface are made on the main controller cards for both wired and wireless interfaces. New radio would only demand a common control and status exchange protocol.

Considering city wide reach, SemTech’s LoRa radio in a private LoRaWAN is preferred until LoRa service providers begin full fledged operation. Microchip’s LoRa module is employed to provide reliable connection to the star center.

Solar Energy Measurement

Akash’s Solar and Hybrid versions implement an Energy Generated Measurement and utilizes this information to factor the light current – so as to have light throughout the night in the predefined illumination profile, ensure longevity of the battery. Cross-referencing this information with the meteorological data, we can estimate the panel cleaning schedule.

Preset Timed Illumination profile

Akash has a Illumination profile implemented as a matrix of duration Vs Light current which is the default operating mode of the street light. These settings can be via communication interface if available or predefined at factory based on customer needs. Akash implements a 4×2 matrix allowing 4 durations at different illumination levels.

Sensor Interfaces

IR remote

Allows for the time duration and LED current configuration post installation of the luminary.

PIR motion sensor array

Passive Infra-Red Motion sensors arrays are employed to larger detection areas and direction of travel.

CO2 Sensor

Optionally, CO2 sensors measures the pollution level at the site and a trend can be established based on the traffic to Akash – Smart Street Light

Temperature and Humidity Sensor

Optionally, temperature and humidity sensors are also interfaced to the Akash – Smart Street Light

Dusk to Dawn

Dusk to dawn operation is initiated by information from the Solar Photo Voltaic Panel, allows freedom from manual task of switching on when dark and switching off when there is light.

Product