16496results about "Emergency protective arrangements for automatic disconnection" patented technology

The present invention provides an improved control methodology for maximum power point tracking (MPPT), anti-islanding, and output current regulation for distributed generation sources connected to a utility grid. The control includes enhancements for MPPT and regulating the inverter output-current that is sourced into the utility grid. In addition, the functions associated with MPPT, anti-islanding detection and output current regulation are integrated together; the MPPT algorithm operates in conjunction with the anti-islanding detection, and the output current regulation operates in conjunction with the MPPT algorithm.

A power conversion system includes a first converter having a DC side and an AC side and a second converter having a DC side and an AC side. The DC sides of the converters are connected in series with a battery connected in parallel across the DC side of the first converter. The AC sides of the converters are connected in parallel across an AC voltage grid. A DC generating power source is coupled across the DC sides of both converters. The first converter is bi-directional with the second converter being either an inverter providing DC to AC conversion or alternately a bi-directional inverter.

A unified policy management system for an organization including a central policy server and remotely situated policy enforcers. A central database and policy enforcer databases storing policy settings are configured as LDAP databases adhering to a hierarchical object oriented structure. Such structure allows the policy settings to be defined in an intuitive and extensible fashion. Changes in the policy settings made at the central policy server are automatically transferred to the policy enforcers for updating their respective databases. Each policy enforcer collects and transmits health and status information in a predefined log format and transmits it to the policy server for efficient monitoring by the policy server. For further efficiencies, the policy enforcement functionalities of the policy enforcers are effectively partitioned so as to be readily implemented in hardware. The system also provides for dynamically routed VPNs where VPN membership lists are automatically created and shared with the member policy enforcers. Updates to such membership lists are also automatically transferred to remote VPN clients. The system further provides for fine grain access control of the traffic in the VPN by allowing definition of firewall rules within the VPN. In addition, policy server and policy enforcers may be configured for high availability by maintaining a backup unit in addition to a primary unit. The backup unit becomes active upon failure of the primary unit.

Disclosed herein is a wireless power transmission system, including: a transmission unit generating and transmitting power for charging a battery; a reception unit receiving the transmitted power and charging the battery with power; and a transmission control unit detecting a charging status of the battery by using the transmitted power, and, if the charging status of the battery is in a damage section due to reflective power, controlling the transmission unit to transmit power lower than power of a normal operation, whereby damage of transmission and reception devices due to a reflective wave can be minimized.

The invention concerns a method and a circuit for maximum power point tracking of a variable power source from a comparison of an image of the power (P) supplied by the power source, the circuit comprising two elements (14, 31) providing different propagating delays to a physical quantity proportional to the power image, a comparator (16) of the outputs of the delaying elements to control a trigger (17) supplying a signal (Q) with two automatic control states to a static power converter, and means (33) for detecting a transitory operating condition from variations in oscillations of an established operating condition and means (32) for modifying the delay input by the slower delaying element (31).

A shorting system, which eliminates persistent arcing faults in power distribution equipment, includes a first shorting switch having separable contacts, an actuation input and a fuse electrically connected in series with those contacts. A second shorting switch includes an actuation input and separable contacts, which are electrically connected in parallel with the series combination of the fuse and the first shorting switch contacts. A detection circuit includes one or more arcing light sensors and an actuation circuit. The light sensors detect arcing fault light and the actuation circuit responsively outputs a first trigger signal to the first shorting switch actuation input to close its contacts. For a persistent arcing fault, which is not eliminated by the first shorting switch, a predetermined time after the first trigger signal, the actuation circuit responsively outputs a second trigger signal to the second shorting switch actuation input to close its contacts.