Smart Meter Voltage Sensing using Optically Coupled Isolators > 자유게시판

This bias situation enables the IR LED diode to operate at a voltage bias condition to maximise the sensitivity of the optically coupled isolator and reduce the current consumption. The IF LED 9 is biased in the forward conduction region utilizing a voltage supply VB 8. This bias situation is set by choosing a present-limiting resistor RD 10 that is equal to the distinction of bias voltage source VB 8 and the ahead voltage VF of the IR LED diode divided by the ahead present IF of the IR LED diode. The tactic contains coupling a resistor voltage divider to a high voltage portion of the smart meter. The strategy also includes optically coupling the high voltage portion to a low voltage portion of the good meter. The method consists of coupling at least one resistor to a high voltage portion of the good meter. The cathode terminal of an infra-pink (IR) LED 9 is related to the first terminal of resistor RS. An optical transistor 57 has a base terminal B that's optically coupled to the IF LED which is a low voltage portion 102. The collector terminal C is linked to the VDD terminal 56. The emitter terminal E is connected to the primary terminal of a resistor RL 58 in the emitter follower configuration.

A sensible meter system voltage and present sensing are performed as voltage drops throughout a shunt resistor in series with the facility line or from a voltage divider linked throughout the power traces. The system and technique must be simply implemented, price efficient and adaptable to current systems. Circuits for the voltage and current sensing method are described utilizing resistors and optically coupled isolators. Another benefit of utilizing resistors and optically coupled isolators is the truth that voltage and current sensing's cannot be tampered as in the case of transformers by inserting a robust exterior magnets within the shut proximity as to saturate the transformer cores. One common approach to attain that is to use voltage and present transformers. The typical power dissipated in resistive hundreds, e.g. household appliances, might be calculated as the product of root-mean-squares of present and voltage averaged over a time interval. Some great benefits of this transformer-much less technique as in comparison with the transformer strategy are direct sensing of current and voltage that allows AC energy and power measurements for non-resistive masses, tamper proof for secure power measurements, compact sizes, and low costs.

But for non-resistive hundreds, akin to AC motors, the typical AC energy might be calculated by the direct product of current and voltage averaged over a period of time. For the reason that voltage induced across a transformer is proportional to the speed of change of present, a direct measurement of the current cannot be simply accomplished immediately from the outputs of a current rework. Pat. No. 9,000,753, entitled "SMART METER VOLTAGE AND Current SENSING Using OPTICALLY COUPLED ISOLATORS", which is incorporated herein by reference. Using optically coupled isolators, the sensed voltages within the excessive voltage power traces are optically coupled and electrically isolated to the low voltage circuits. These voltages are optically coupled and electrically isolated to the inputs of the low voltage circuits through the use of optically coupled isolators. A transformer-much less technique and system for voltage and current sensing using voltage drops across resistors is disclosed. The power usage could be accessed for instance by displaying internet pages utilizing any machine that is connected to the native server or the web. On this embodiment, the local server 1 issues a command to the coordinator 2 which executes the command by sending a corresponding information packet wirelessly to the sensible meters 3 by a radio frequency (RF) link, e.g. ZigBee that may or might not support an industry standard reminiscent of IEEE 802.14.5. Then the good meters 3 send an applicable response again to the coordinator 2 by the identical RF hyperlink.

In another embodiment, the native server 1 is connected to the coordinator 2 wirelessly. The native server 1 issues commands to the coordinator 2 by a coordinator-server interface control register. The good meter system 50 comprises an area server 1 connected to a coordinator 2 and smart meters 3 (good meter 1-N). In one embodiment, the local server 1 is connected to the coordinator 2 through wires. The power usage can be analyzed to allow system management, e.g. minimize off the facility if necessary. In smart meter system voltage and current sensing, electrical isolation between the excessive voltage and the low voltage domains is important. There is a need to boost system performance, reliability, testability and manufacturability of the sensible meter throughout the product manufacturing and prototyping. The present invention is said typically to meters for measuring power and extra notably to a wise meter system. The good meter system 50 is a many-to-one information communication topology.