8 results about "Voltage amplitude" patented technology

Disclosed are a myoelectric prosthetic hand force tactile feedback method and a tactile feedback myoelectric prosthetic hand system. A three-dimensional force sensor is mounted on a wrist of a mechanical prosthetic hand, and a stress shaft of the three-dimensional force sensor is connected with a mechanical prosthetic hand base via a flange and senses stress conditions in directions of three axes of the mechanical prosthetic hand. After the three-dimensional force sensor receives three-dimensional force action, force signals are converted into voltage signals via a bridge principle, the voltage signals are inputted into a control module provided with a single chip microcomputer and a motor driving circuit, the single chip microcomputer acquires the voltage signals which are transmitted from the three-dimensional force sensor and stand for force action on an X axis, a Y axis and a Z axis, positive and negative directions of the voltage signals include directions of X+, X-, Y+, Y-, Z+ and Z-, corresponding pulse width modulation signals are outputted according to the voltage amplitudes in the six directions, namely measured magnitude of stresses in the six directions, and the motor driving circuit drives miniature vibrators in the corresponding directions, so that amplitudes of the vibrators are in direct proportion to the voltage amplitudes in the corresponding directions.

The invention discloses a calculation method for theoretical line loss of a distribution network considering a small power supply. The calculation method comprises the following steps of: obtaining aresistance of each branch of the distribution network, the active power, a reactive power, a voltage and current data of each node; counting a power consumption of each small power node, using an average current method to calculate the power loss of the distribution network; calculating injection current of each node according to the active power, the reactive power, a voltage amplitude and a current amplitude of each node; forming a path mutual resistance matrix by using a search method; obtaining an accurate electric energy loss calculation model, and a loss calculation model based on the average current method by adopting a loop analysis method based on the path mutual resistance matrix and the injection current of each node; using the accurate power loss calculation model, and the losscalculation model based on the average current method to obtain a calculation error of the average current method, that is, a correction amount of loss; and calculating the sum of the power loss obtained by the average current method and the correction amount of the loss, and obtaining the theoretical power loss of the distribution network.

A semiconductor integrated circuit device is provided, in which a node from which an output signal of a level shifter is sent can be initialized such that the potential thereof be set at a desired logic level at the time of power supply. The semiconductor integrated circuit device includes a level shifter 6 and two capacitors N10 and C0. The level shifter 6 receives an input signal and converts the received signal to a signal having a voltage amplitude greater than that of the received signal, then to provide the signal to a node D3. The capacitor N10 is connected to the node D3, and the capacitor C0 is connected in series with the capacitor N10. The capacitor N10 is formed of a MOS transistor having a gate connected to the node D3 and a source and a drain both connected to the capacitor C0.

The invention discloses a voltage disturbance generation device which comprises a three-phase rectifier module. The three-phase rectifier module is connected with a three-phase chopper voltage regulation module A, a three-phase chopper voltage regulation module B and a three-phase chopper voltage regulation module C through a DC LC filter. The three-phase chopper voltage regulation module A is connected with a full-bridge inversion module A through a three-phase DC LC filter A; the three-phase chopper voltage regulation module B is connected with a full-bridge inversion module B through a three-phase DC LC filter B; and the three-phase chopper voltage regulation module C is connected with a full-bridge inversion module C through a three-phase DC LC filter C. The full-bridge inversion module A, the full-bridge inversion module B and the full-bridge inversion module C respectively have two paths of output, wherein one paths of outputs are connected with the input end of a three-phase AC LC filter, and the other paths of outputs are mutually short circuited and are connected with the three-phase AC LC filter simultaneously. The problems that continuously-changing output voltage amplitude cannot be realized in a conventional voltage disturbance generation device, and the control difficulty is high are solved; and the voltage disturbance generation device is simple in structure and easily-controlled.

The invention discloses a line voltage based earth-free power distribution network three-phase power flow calculation method. Structural data and parameter information of the network, control information of PV nodes and node load information are input based on programs through a computer, and the information is initialized; then the node admittance matrix and the jacobian matrix constant term of the network based on the line voltage are calculated; next, a node current unbalance equation of the network unbalance nodes, a power constraint equation of constant current star-shaped load nodes, a general active power constraint equation of the PV nodes and a line voltage amplitude constraint equation are taken into comprehensive consideration; the real and imaginary parts of the respective node line voltages FORMULA as shown in the specification, the real and imaginary parts of the injection current FORMULA as shown in the specification, of the constant current star-shaped load nodes, and the real and imaginary parts of the injection current FORMULA as shown in the specification, of the PV nodes are taken as the state variables; the Newton-Raphson algorithm is adopted based on the injection current ways to calculate the corresponding unbalance amount and the jacobian matrix; and finally the state variables are updated and convergence judgment is carried out to realize the earth-free power distribution network three-phase power flow calculation.

The invention discloses a commutation failure starting value setting method and device, belongs to the field of safety and stability analysis and control of an electric power system, and provides the commutation failure starting value setting method and device aiming at the problem that commutation failure prediction control starting value setting of a direct current system is not high in adaptability. According to the method, the severity of the direct-current system fault is determined by detecting the maximum values of zero-sequence voltage and three-phase voltage changed by alpha and beta in the first period after the fault, and the obtained voltage amplitude in the first period after the fault serves as a reference and is multiplied by a certain coefficient to serve as a commutation failure prediction control starting value. Therefore, the commutation failure prediction control starting value can be adaptively set in different fault scenes. Simulation results show that the commutation failure prediction control starting value can be effectively set, and compared with an existing method, the commutation failure suppression effect is improved to a certain extent.

The invention provides a simulation method and system based on electric energy meter power-down data storage. The simulation method includes: according to preset capacitance capacity, preset load current and preset voltage amplitude, calculating power-down time, and generating simulation waveform; outputting the simulation waveform to an electric energy meter, and receiving and storing power-downdata fed back by the electric energy meter, wherein the power-down data are generated by the electric energy meter; judging whether the power-down data are complete or not; if not, increasing power-down time. By the simulation method and system, whether the power-down data stored by the electric energy meter are complete or not can be evaluated effectively.