Patent ID: 9689901
Date: 2017-06-27
CPC Classifications: G01R,H01F,H02M,Y02B,Y04S

Claim:
1. A system for power management comprising: at least one self-powered power sensor (SPPS) coupled around an alternating current (AC) power line connected to a circuit breaker, each SPPS of the at least one SPPS comprising: an analog section comprising a current transformer comprising a transformer core configured to mount around the AC power line making it a primary winding of the current transformer, the analog section harvesting energy from a secondary winding wound around the transformer core, and storing the harvested energy for use by components of the SPPS; a microcontroller coupled to the at least one analog section to receive at least an analog signal responsive to the alternating current in the AC power line; a resonance capacitor coupled in parallel to the secondary winding of the current transformer to resonate with the secondary winding inductance at a primary frequency, the resonance capacitor's value being selected so that maximum resonance is achieved at low primary currents; a memory coupled to the microcontroller; and, a transmitter enabled to periodically transmit, under the control of the microcontroller, information respective of the power consumption of the AC power line, upon determination that there is sufficient power to perform the transmission; a communication bridge configured to communicate with the at least a SPPS and further coupled to a network thereby enabling communication over the network by the at least a SPPS; a management server coupled to the network and configured to receive information from the communication bridge respective of the at least one SPPS; and a database coupled to the network for storing at least the information; wherein the current flowing through the circuit breaker ranges from a maximum current to low currents: wherein the secondary winding wound around the transformer core, the current through the AC power line, when present, being of a fixed frequency; wherein the primary frequency resonated by the resonance capacitor is the fixed frequency of the current flowing through the circuit breaker at a low range of current through the circuit breaker and wherein magnetization is at a low non-linear range of a magnetization curve of the transformer core; wherein the analog section harvesting energy from the secondary winding supplies power to the SSPS responsive of harvesting energy from the secondary winding.