Abstract:
A vehicle includes an engine and alternator having a field coil and a plurality of output windings, a field current controller configured to receive an AC input and convert the AC input into a regulated DC output that is supplied to the field coil of the alternator, and a controller configured to monitor at least one operating parameter of the field current controller and to compare a monitored value of the at least one operating parameter to a threshold range.
Abstract:
A first switch and a second switch connected in series to both terminals of a DC power source. A signal generation circuit generates a feedback signal based on the DC voltage detected by the voltage detection circuit, and outputs the feedback signal, the feedback signal for turning the first and second switches on and off. A burst oscillation circuit that generates a burst oscillation signal based on a feedback signal and turns the first switch element and the second switch element on and off based on the burst oscillation signal when the standby state is detected. The burst oscillation circuit comprises a capacitor and a rapid charge circuit. When this device returns from standby state to normal state, the rapid charging circuit charges the capacitor after the feedback signal exceeds the cancellation threshold voltage.
Abstract:
A method for controlling a switching regulator includes defining a waiting time during which a trigger signal corresponding to a recirculation signal of the switching regulator is ignored holding a control switch in an open condition, and detecting a number of local valleys of the recirculation signal during the waiting time. In particular, defining the waiting time is performed for each switching cycle by adding a first value, which is determined on the basis of a load on the regulator, to a second variable value, which is proportional to the number valleys detected during the waiting time of the preceding switching cycle.
Abstract:
A DC/DC power transformer is provided which is an arrangement for direct transformation of high electric power from one DC voltage level to another DC voltage level without an intermediate AC voltage network. The DC voltage is today basically used for transmission of high electric power at long distances. The DC voltage levels for these transmissions are normally high. The DC/DC power transformer allows several DC voltage levels to be used in one and the same DC voltage network. The principle for this arrangement is that the valve windings (43, 45) from one or several converter transformers (47) are connected to two valve bridges, which generate opposing cyclically variating magnetic flows in the transformer cores (44). One of the valve bridges is operated as an inverter (42) and the other as a rectifier (46) and in this manner the power is transformed from one DC voltage level (U.sub.d1) to another (U.sub.d2). At high voltage levels the leakage inductances in the transformers will be high as a consequence of the insulation levels and therefore special arrangements must be made in order to commutate the magnetic energy from one phase of the transformer to another without creating great losses.
Abstract:
A resonance inverter includes a DC power source, a resonance capacitor, an inductor, and a plurality of semiconductor switches. The resonance capacitor and inductor form a parallel resonant circuit. The inverter further includes control means for detecting a peak value of the voltage across the resonance capacitor, and for alternately conducting said semiconductor switches with a certain lead phase with respect to the peak point of the capacitor terminal voltage.
Abstract:
A switching regulator circuit for utilization with power supplies supplying a high DC output current including a plurality of control rectifiers and inductive reactors with sequential gating of the rectifiers at regular intervals for providing overlapped output current pulses from the reactors. An output circuit receives the rippled current comprised of the overlapped output current pulses for reducing the ripple therein. The output circuit includes a choke in series with the output which induces phase shift between the rippled current and the output current. A sensing winding associated with the choke eliminates the phase shift voltage for forming a feedback signal as an input to a control circuit. The control circuit utilizes the feedback signal to control the rate at which the rectifiers are gated sequentially.
Abstract:
A power converting apparatus and method comprising a transformer and converting circuit mounted with the transformer for converting direct current to a series of pulses in the primary winding which includes a pulse train forming an effective current with reciprocal positive and negative sine wave components for each half cycle of chosen frequency. A gating circuit is mounted with the transformer for sequentially passing the pulses in the positive sine wave components followed by the pulses in the negative sine wave component, the gating circuit passes the pulses received in the secondary winding synchronously with the pulses in each half cycle of the pulse train to form a chosen frequency alternating current component. A filter is mounted with the gating circuit for removing selected components of the received signal while providing an output of the chosen frequency alternating current.
Abstract:
A burst oscillation circuit operates switches in a burst oscillation mode based on a feedback signal. A first burst operation cancellation threshold voltage comparator compares a first burst operation cancellation threshold voltage set higher than a voltage of the feedback signal that a load current reaches the standby threshold and a voltage of the feedback signal, and outputs a first output signal. A second burst operation cancellation threshold voltage comparator compares a second burst operation cancellation threshold voltage set lower than the voltage of the feedback signal that the load current reaches the standby threshold and higher than a voltage of the feedback signal during a non-oscillation period of the burst oscillation operation and the voltage of the feedback signal and outputs a second output signal. A standby cancellation circuit generates a standby cancel signal to cancel the standby state based on the first and second output signal.
Abstract:
A charger with over-voltage and over-current protection and a method for using the same are provided. The charger comprises a first interface, a second interface, a voltage stabilizing unit, a control unit, an input voltage sampling unit, a switch unit, and a current sampling unit. The voltage stabilizing unit receives an input voltage of an external power supply and provides a constant working voltage to the control unit. The input voltage sampling unit detects the input voltage real-timely. The current sampling unit detects charging current of the battery rod real-timely. The control unit determines whether the input voltage detected by the input voltage sampling unit generates over-voltage or not, or determines whether the charging current detected by the current sampling unit generates over-current or not, and controls the switch unit to turn on or turn off according to the determination results.