Abstract: The present disclosure relates to an over-voltage prevention apparatus and method of a distribution line connected with a distributed generator, which sets a range of a dispatched voltage based on a current voltage of a Pole Mounted Automatic Voltage Regulator (PVR) and a voltage at a connection point of a distributed generator to control so that the dispatched voltage is output within the corresponding range.

Abstract: The invention relates to a method for controlling an electrical transmission link (3) between first and second AC voltage buses (11, 21) comprising a high-voltage DC line (320), first and second AC/DC converters (321, 322) connected to the high-voltage DC line (320), comprising: retrieving a setpoint active power value (Pdc0) applied to a converter (321, 322); retrieving the instantaneous values V1 and V2 of the voltages on the first and second buses; wherein the setpoint active power of the first or of the second converter is modified by a value including a term ?Pdc, so as to impose new dynamics on the first and second areas, where: ?Pdc=?Pdcs+?Pdca.

Abstract: The present disclosure relates to a power module that has a housing with an interior chamber and a plurality of switch modules interconnected to facilitate switching power to a load. Each of the plurality of switch modules comprises at least one transistor and at least one diode mounted within the interior chamber and both the at least one transistor and the at least one diode are majority carrier devices, are formed of a wide bandgap material system, or both. The switching modules may be arranged in virtually any fashion depending on the application. For example, the switching modules may be arranged in a six-pack, full H-bridge, half H-bridge, single switch or the like.

Abstract: A method of providing a salt solution at a wellbore site includes delivering solid salt in a mixing tank containing water from a local source and pumping the water through nozzles in the mixing tank using a pump adjacent to the mixing tank to circulate the water in the mixing tank and form a concentrated brine by dissolving the solid salt in the water. The concentrated brine is transferred from the mixing tank to a reservoir using the pump, and the concentrated brine is diluted with additional water from the local source to form a dilute brine. A related mixing tank and a system including the mixing tank and a vehicle structured and configured for travel over a roadway and within an oilfield site.

Abstract: A rotor position judging unit detects a rotor position by utilizing induced voltages generated at respective phases of an armature winding. While a field current flowing through a field winding rises toward a target value (while the field current temporally changes), induced voltages are generated at the respective phases of the armature winding by temporal differentiation of a magnetic flux which interlinks with the armature winding. The rotor position judging unit detects the rotor position (d-axis of a rotor) on a basis of a table containing combination of amplitude ratios and polarities of the induced voltages generated at the respective phases.

Abstract: An alternator and a rectifier are provided. The rectifier includes a gate driving circuit, a logic circuit, and a comparison circuit. The gate driving circuit generates a gate voltage, and a control terminal of a transistor receives the gate voltage. The gate driving circuit receives a control signal, and adjusts the gate voltage according to the control signal, so as to control a conductivity degree of the transistor. The logic circuit generates the control signal and a switch signal according to a comparison result and selects a selected voltage according to the switch signal. The comparison result is generated by comparing a sensing voltage of a first terminal of the transistor with the selected voltage.

Abstract: Example implementations relate to smart bypass diode bridge rectifiers. For example, a device can include a power over Ethernet input. In some examples, the device can include a plurality of smart bypass diodes connected to the power over Ethernet input to form a bridge rectifier. In some examples, the device can also include a powered device connected to the bridge rectifier.

Abstract: A system for high powered wireless power delivery and charging includes an electronic device having a wireless charging module. The wireless charging module includes a power management module, the power management module configured and executing instructions to enable and disable the power delivery or charging of the electronic device based on whether a valid charging circuit exists, the power management module additionally configured and executing instructions to prevent a detection of an invalid load.

Abstract: There is provided a vehicle-power-generator control apparatus and the control method thereof that does not notify a passenger of any erroneous alarm indicating an abnormality in an electric power generator, even when a power-generation stop command is received. it is determined that a vehicle power generator is not rotating, when the rotation speed, of the vehicle power generator, that is detected based on a power-generation voltage generated across an armature winding of the vehicle power generator is the same as or lower than a predetermined value; there is generated a power-generation stop holding signal obtained by delaying by a predetermined time a time point at which a power-generation stop signal, generated when the decoded command signal is a power-generation stop command signal for stopping electric-power generation, stops; then, the non-rotation determination signal is masked and invalidated, based on the power-generation stop holding signal.

Abstract: A method and an apparatus for controlling MHSG of a mild hybrid electric vehicle, may include detecting data for controlling the MHSG; determining a target torque of an engine based on the data; determining whether a pressure difference between a front end portion and a rear end portion of a particulate filter is equal to or greater than a first pressure based on the data; determining a loss amount of combustion torque of the engine based on the pressure difference when the pressure difference is equal to or greater than the first pressure; and performing torque compensation control of the MHSG based on the target torque of the engine and the loss amount of the combustion torque of the engine.

Abstract: A circuit arrangement for detecting a zero crossing of an alternating current is provided. The circuit arrangement includes a load through which the alternating current can flow, and an evaluation unit connected to the load and configured to evaluate an electrical voltage formed at the load, and to determining zero currents. The load comprises a capacitor through which the alternating current or a current to be measured derived therefrom can flow, and the evaluation unit is configured to account for a phase shift caused by the capacitor for determining the zero currents.

Abstract: Provided is a power conversion device that can suppress a surge to be generated when a load, such as a battery, is disconnected from an output of an AC generator. A rectifier circuit connected between an output portion of the AC generator and a first load rectifies the output of the AC generator and supplies the rectified output to the first load. A switch circuit connected between the output portion of the AC generator and the second load rectifies the output of the AC generator and supplies the rectified output to the second load, on condition that a drive signal is in a first signal state indicating permission of a power supply from the AC generator to the second load. Additionally, the switch circuit transitions from a conductive state to a non-conductive state in response to the output of the AC generator, on condition that the drive signal is in a second signal state indicating prohibition of the power supply from the AC generator to the second load.

Abstract: Automatic voltage regulation is shown involving full wave rectifying a power signal and generating a reference corresponding to an operating voltage level, line sampling the power signal and comparing it to the reference to generate a line sync signal synchronized to the power signal. Producing 90° out of phase signals synchronized to the line sync signal with a PLL locked onto the line sync signal that outputs a phase error signal. Generating a quadrature signal from the phase signals. Sampling the peaks of the rectified power signal using the quadrature signal to produce a control signal. Subtracting the error signal and damping signal from the reference to produce a duty cycle modulation signal. The duty cycle modulation signal controls a duty cycle of a field voltage control signal that oscillates at a predetermined frequency. The field voltage control signal is low-pass filtered to produce the damping signal.

Abstract: A power grid of renewable sources is stabilized. Inverters for connecting power sources, such as wind turbines, batteries, or photovoltaics, to a grid are used to damp grid oscillations. The damping is distributed to the inverters, but based on measurements for the grid rather than local measurements. The control of the damping is based on grid wide analysis, and the damping is performed proportionately by already existing inverters distributed throughout the grid.

Abstract: A power oscillation damping controller is provided for a power generation device such as a wind turbine device. The power oscillation damping controller receives an oscillation indicating signal indicative of a power oscillation in an electricity network and provides an oscillation damping control signal in response to the oscillation indicating signal, by processing the oscillation damping control signal in a signal processing chain. The signal processing chain includes a filter configured for passing only signals within a predetermined frequency range.

Abstract: Disclosed is an alternator overvoltage protection circuit having a TRIAC and a MOSFET. The TRIAC is electrically connected to the MOSFET and the TRIAC is electrically connected to a magneto. The TRIAC is configured to ground the magneto when triggered by the MOSFET. The MOSFET is electrically connected to an alternator and configured to conduct when the alternator operates in an overvoltage condition. Also disclosed is a method of alternator overvoltage protection for a piece of outdoor power equipment, the method including providing a TRIAC and an alternator rotated by an engine having a magneto, wherein the alternator outputs a voltage when rotated by the engine. The method further includes configuring the TRIAC to ground the magneto when the alternator operates in an overvoltage condition, thereby disabling the magneto, which stops the rotation of the engine and stops the alternator from outputting voltage.

Abstract: A method of starting a wind turbine generator of any type of polyphase AC machine, including, but not limited to, brushless DC or permanent magnet machines is disclosed. The machine starts from a dead stop or from low speed operation and is accelerated to the cut in speed for power production. The start-up is realized utilizing the common set of electrical conductors and the power converter also used for capturing the generated power. Under initial operation, the power converter executes a PWM modulation technique to drive the machine. Periodically, the PWM modulation is stopped to read the electrical position of the generator.

Abstract: An integrated generation control system includes at least one integrated control module, a rectification module, a communication module, a rectifier, a permanent magnet alternator, a generator, a maintenance module, a local control unit and a battery. The integrated control module includes an automatic voltage regulator, a power system stabilizer and an extensive gate controller. The rectification module is connected to the integrated control module. The communication module is arranged between the integrated control module and the rectification module. The rectifier is connected to the integrated control module and the rectification module. The permanent magnet alternator is connected to the rectifier. The generator is connected to the integrated control module.

Abstract: An arrangement for controlling a synchronous generator having a stator comprising at least one stator winding and having a rotor with an electromagnet driven by a field current is provided. The rotor is rotatable relative to the stator. The electromagnet is inductively coupled to the at least one stator winding. The arrangement includes a measurement system configured to measure at least one quantity and a controller configured to cause shutting down the field current when the at least one quantity satisfies at least one criterion associated with at least one malfunction.

Abstract: A vehicular charging system includes: a generator which has a field coil and is mounted on a vehicle; a storage battery which stores power; a storage state detection sensor which detects a charge state; and a power generation driving torque control device which calculates an actual value and a target value of power generation driving torque of the generator, and controls the generator based on the calculated target value. The power generation driving torque control device controls the generator based on a first target value of the power generation driving torque when a running state of the vehicle moves into a deceleration mode, and decreases the power generation driving torque to control the generator based on a second target value of the power generation driving torque when a charge state of the storage battery reaches a reference value, the second target value being smaller than the first target value.

Abstract: The present invention discloses a method and an apparatus for power control. An apparatus for power control in accordance with an embodiment of the present invention can include: a voltage comparing part configured to compute an error voltage by using a measured voltage measured at the generator and a reference voltage that is designated; a control module configured to compute a first reactive power value for power control of the generator by being inputted with the error voltage; and a driving module configured to compute a reference reactive power value by using the first reactive power value and a second reactive power value computed using an active power value of the power converter and configured to control the power converter in correspondence with the computed reference reactive power value.

Abstract: Systems and methods for monitoring excitation of a generator based on a faulty status of a generator breaker are provided. According to one embodiment, a system may include a controller and a processor communicatively coupled to the controller. The processor may be configured to receive, from a contact associated with a generator breaker, a reported status of the generator breaker, receive operational data associated with one or more parameters of a generator associated with the generator breaker, and correlate the reported status of the generator breaker and the operational data. Based on the correlation, the processor may establish an actual status of the generator breaker, and, based on the actual status, selectively modify a mode of excitation of the generator.

Abstract: Provided is a power-generation control device capable of appropriately using a drive belt looped around a power generator and an internal-combustion engine mounted on a vehicle. The device monitors a difference between an actual generated current of a rotating electrical machine and an estimated generated current estimated from estimated power-generation torque for controlling power generation of the rotating electrical machine, which corresponds to a power-generation torque command, or the like. When a difference equal to or more than a predetermined value occurs between the actual and the estimated generated currents, the power-generation control device limits the estimated power-generation torque so as to be reduced, and further limits the estimated power-generation torque with use of learning limiting power-generation torque calculated based on the estimated power-generation torque at a time when the difference has occurred between the actual generated current and the estimated generated current.

Abstract: An integrated power system suitable for simultaneously powering marine propulsion and service loads. The system includes: (a) at least one generator configured with at least first and second armature windings configured to output respective first and second alternating current power signals of different voltages, the at least two armature windings positioned within the same stator slots so that they magnetically couple; (b) at least first and second rectifier circuits coupled to said generator to convert said first and second alternating current power signals into first and second direct current power signals; and (c) a first load to which said first direct current power signal is coupled and a second load to which said second direct current power signal is coupled.

Abstract: A DC chopper comprising a control unit and a power circuit and a DC chopping method for a DFIG (doubly fed induction generator) system are provided. The input terminal of the control unit is coupled to a DC capacitor of a converter to detect a DC voltage. The power circuit includes input terminals, an overvoltage protection module, a rectifier module and output terminals. The overvoltage protection module comprises at least one discharge unit formed from a discharge resistor and a switch element, and the rectifier module is coupled in parallel to the overvoltage protection module. When a grid voltage drops, the control unit outputs a corresponding control signal to drive the switch element to be ON or OFF, and the output terminal of the power circuit absorbs a portion of rotor inrush current, so as to impose over-current protection.

Abstract: A generator system includes a generator having a stationary portion and a rotating portion. The generator includes a permanent magnet based exciter with permanent magnets disposed on the stationary portion. A first channel includes a first main field winding and a first main field power converter disposed on a rotating portion. The first main field power converter selectively delivers voltage from the exciter winding to the first main field winding. A second channel includes a second main field winding and a second main field power converter disposed on the rotating portion. The second main field power converter selectively delivers voltage from the exciter winding to the second main field winding. A generator control unit is connected to the first channel and the second channel. The generator control unit monitors an output voltage at each of the first channel and the second channel and generates the first and second control signals based on the output voltage.

Abstract: An electrical generator includes a stator having fractional-slot concentrated windings and a rotor having field windings. A drive is provided having a circuit to control current flow to the field windings and a controller to input an initial DC field current demand to the circuit to cause the circuit to output an initial DC field current representative of a DC field current demand that would cause an electrical generator having sinusoidal stator windings to output a desired AC power. The controller receives feedback on the magnetic field generated by the initial DC field current, isolates an ideal fundamental component of the magnetic field based on the feedback and to generate a modified DC field current demand, and inputs the modified DC field current demand to the circuit, thereby causing the circuit to output an instantaneous non-sinusoidal current to the field windings to generate a sinusoidal rotating air gap magnetic field.

Abstract: Starting and stopping an engine is automatically controlled based on a load without using a relay. An inverter engine-driven power generator has an alternator, a rectifying circuit, a DC/DC converter, and an inverter circuit. A load detection circuit is connected to an output of the inverter circuit in parallel. A load detection line of the load detection circuit is connected to an output line of the inverter circuit in parallel via resistors. A power supply formed of a battery is connected to the load detection line. A decision circuit outputs a load detection signal when a current having a preset value or more flows through the load detection line. A drive/stop CPU starts the engine in response to the load detection. The resistors are set at a resistance value which does not influence a load to which a generator output is supplied.

Abstract: A power supply apparatus capable of setting a ripple current to be not more than an acceptable value regardless of an input voltage is obtained. The apparatus calculates switching frequency by a current detected by a current detector so that the switching frequency is set to be low if the current is large and the switching frequency is set to be high if the current is small. The switching frequency is set to be high if the input voltage is high and switching frequency is set to be low if the input voltage is low depending on a voltage inputted to an input terminal; and a switching element is controlled by restricting the switching frequency so that the switching frequency to be set by the current detected by the current detector is not lower than the switching frequency to be set by the input voltage.

Abstract: A generator system includes a generator having a stationary portion and a rotating portion. The generator includes a permanent magnet based exciter with permanent magnets disposed on the stationary portion. A first channel includes a first main field winding and a first main field power converter disposed on a rotating portion. The first main field power converter selectively delivers voltage from the exciter winding to the first main field winding. A second channel includes a second main field winding and a second main field power converter disposed on the rotating portion. The second main field power converter selectively delivers voltage from the exciter winding to the second main field winding. A generator control unit is connected to the first channel and the second channel. The generator control unit monitors an output voltage at each of the first channel and the second channel and generates the first and second control signals based on the output voltage.

Abstract: An electric power generation system and method that permits enhanced power generation efficiency when applied to rotating electric power generation systems is disclosed. The system may be broadly described as generally improving energy generation efficiency by improving the efficiency of electric current extraction from stator coils in many alternator-based electric power generation systems. The system disclosed comprises a number of preferred embodiments, some of which utilize buck-boost converter technologies in conjunction with super-diode excitation/rectification to minimize I2R power losses within rotating power generation system components while at the same time reducing heat losses and thus increasing overall rectification circuitry system reliability.

Abstract: A motor vehicle regulator, including electronic regulation circuits, which can produce an excitation current in accordance with a difference between a set voltage and an output voltage measured at the terminals of an electric battery of the vehicle. The regulation circuits including a programmable signal processing interface for producing a signal, which is representative of the excitation current. The interface receives as input a plurality of signals which are representative of the excitation current. The interface including a device capable of selecting a signal which is representative, from amongst the plurality of representative signals, of the method for applying different forms of processing to the representative signal selected, and a second device for selection of processing to be applied to the representative signal. The representative signal, and the processing to be applied, being selected according to a program provided to the programmable signal interface.

Abstract: A field winding type rotary electric machine includes: a controller; a field current integration portion provided in the controller to calculate an integral value by integrating an excessive field current exceeding a field current threshold; a field current limiting portion provided in the controller and carrying out limiting processing to limit a field current to or below a predetermined value when the integral value reaches an integral value threshold defined as a reference value at or above which the field current is limited; a controller power supply connection switch switched ON and OFF for power feeding to the controller; a controller power supply connection determination portion switching ON and OFF the controller power supply connection switch; and a power feeding ON state maintaining portion maintaining an ON state of the power feeding to the controller from start to end of the limiting processing by the field current limiting portion.

Abstract: An adaptive sliding-frequency triggering ignition method for electronic ballast of high pressure gas discharge lamp includes the steps of: measuring an accurate value of free oscillation frequency of the ballast load loop by using a single-chip before sliding-frequency triggering ignition, implementing safe and reliable sliding-frequency triggering ignition after calculating the initial frequency and ending frequency of sliding-frequency triggering ignition according to the accurate value. The method can safely and reliably finish sliding-frequency triggering ignition course, thus improving the parameters such as the quality, life of the high pressure gas discharge lamp electronic ballast.

Abstract: A power supply apparatus capable of setting a ripple current to be not more than an acceptable value regardless of an input voltage is obtained. The apparatus calculates switching frequency by a current detected by a current detector so that the switching frequency is set to be low if the current is large and the switching frequency is set to be high if the current is small. The switching frequency is set to be high if the input voltage is high and switching frequency is set to be low if the input voltage is low depending on a voltage inputted to an input terminal; and a switching element is controlled by restricting the switching frequency so that the switching frequency to be set by the current detected by the current detector is not lower than the switching frequency to be set by the input voltage.

Abstract: The control device including: a power transistor (502) for controlling conduction/non-conduction of a field coil (3) in accordance with an output voltage of an AC generator (1) mounted on a vehicle; an RPM detection section (511) for detecting an RPM of the AC generator (1); a drive duty setting section (510) for determining whether or not the RPM detected by the RPM detection section (511) is equal to or higher than a predetermined threshold, and reducing a conduction ratio of the field coil (3) when determining that the RPM is equal to or higher than the predetermined threshold; and a driver (504) for driving the power transistor (502) based on the conduction ratio. In this manner, the conduction ratio of the field coil (3) is reduced to suppress the drive torque.

Abstract: An alternator has a field coil that produces a magnetic field which induces electricity in an coil arrangement. A field coil excitation system includes a generator with an output coil assembly for producing alternating electricity. A rectifier converts the alternating electricity into voltage and direct current at two nodes. A capacitor, between the nodes, has capacitance that forms a resonant circuit with inductance of the output coil assembly. Due to that resonant circuit, the voltage and direct current oscillate in a predefined phase relationship. A switch and the field coil are connected in series between the nodes. A controller renders the switch conductive for a time period specified by a received control signal. The switch is rendered non-conductive at the first occurrence of a minimum current level after the time period ends. The predefined phase relationship enables the minimum current level to be detected by sensing the voltage.

Abstract: In a control device for a vehicle AC generator, a voltage control includes target voltage adjusting means for adjusting a target voltage value in response to a target change command from an external control unit and a gradual excitation control circuit that controls an excitation duty to increase according to an excitation duty control characteristic when a vehicle load increases and when the target voltage adjusting means varies the target voltage value to a lower value. The gradual excitation control circuit includes duty characteristic varying means for varying the excitation duty control characteristic. The duty characteristic varying means varies a rate of increase of the excitation duty in a predetermined region of the excitation duty control characteristic in comparison with its other region.

Abstract: A power source device for rectifying the output of an AC generator in which magneto coils are in a star-shaped connection in three phases. The device includes a control rectifier circuit configured from a first control rectifier circuit for performing full-wave rectification on three-phase AC voltages, and a second control rectifier circuit for performing full-wave rectification on AC voltages obtained between neutral and each of two-phase AC output terminals selected from the three-phase AC output terminals of the generator, as well as on AC voltage obtained between the selected two-phase AC output terminals; and a controller controlling the first and second circuits so that the output of the first circuit is supplied to the load when the rotational speed of the generator is equal/less than a set speed, and the output of the second circuit is supplied to the load when the rotational speed exceeds the set speed.

Abstract: A field winding type rotary electric machine includes a motor generator; a field current detection unit; a field current control unit which controls a field current; a field current limiting determination section which calculates a field current integration value and determines whether or not the field current integration value reaches a predetermined field current integration threshold value; and a field current limiting command section which, when it is determined that the field current integration value reaches the predetermined field current integration threshold value, outputs a command which sets the field current to be lower than or equal to a predetermined field current limiting value to the field current control unit during a predetermined limiting time, and outputs a command which changes the predetermined limiting time depending on the field current. Accordingly, a temperature rise of the machine is suppressed and limiting of the field current can be released as needed.

Abstract: A method and system for dissipating energy in a direct current (dc) bus of a doubly-fed induction generator (DFIG) converter during a grid event is described. In one aspect, the method comprises monitoring operating conditions of an electrical system, the electrical system comprising at least a DFIG generator and a line side converter and a rotor side converter connected by a dc bus having a dynamic brake connected thereto; detecting an overvoltage on the dc bus or a condition indicative of an overvoltage on the dc link is detected, the overvoltage on the dc bus or condition indicative of the overvoltage caused by a grid event; and causing energy in the dc link to be dissipated using the dynamic brake.

Abstract: In one aspect, a method for controlling a dual-fed induction generator (DFIG) during a high-voltage grid event is provided. The method includes setting, by a controller, an output of a closed-loop portion of a rotor current regulator to a fixed value such that a predictive feed-forward path sets an internal voltage for the DFIG; and detecting, by the controller, a condition of high dc voltage on a dc link or a condition predictive of high dc voltage on the dc link, and in response reduce a rotor torque producing current command to approximately zero, wherein the dc link connects a line-side converter connected to a system bus and a rotor-side converter connected to a rotor of the DFIG.

Abstract: The invention relates to a synchronous power controller for a generation system based on static power converters, said controller comprising two main blocks referred to as: block 1 (electric block) (10) and block 2 (electromechanical block) (20), electric block 1 (10) being, in turn, formed by a virtual electrical characteristic controller (11) and a virtual 10 admittance controller (12) and the electromechanical block 2 (20) being formed by a virtual electromechanical characteristic controller (21) and an inertia and damping factor controller (22).

Abstract: A power generator has a battery and an alternator driven by an engine. The battery assists a power energy of the alternator. An inverter circuit is connected to an output of a rectifying circuit. A DC/DC converter boosts a voltage of the battery and inputs the boosted voltage into a constant power regulator. The constant power regulator boosts an input voltage and secures a certain power. An output voltage of the rectifying circuit is monitored by a monitoring means and an output voltage of the battery is monitored by a monitoring means. When the output voltage of the rectifying circuit is equal to or less than a rated voltage, an auxiliary power value corresponding to the remaining amount of the battery is set as a power target value of the constant power regulator.

Abstract: In a power generator, three-phase armature windings and a switching unit are provided for each phase armature winding. The switching unit includes a pair of a high-side switching element with a first diode and a second low-side switching element with a second diode. The switching unit rectifies, through at least one of the high-side switching element, the first diode, the second low-side switching element, and the second diode, a voltage induced in each phase armature winding. A zero-cross detector detects a point of time when a phase current based on the voltage induced in each phase armature winding is reversed in direction as a zero-cross point of the phase current. A determiner determines an off timing of the high-side switching element or the low-side switching element for each phase armature winding relative to the zero-cross point detected by the zero-cross detector.

Abstract: The present invention relates to a control device for a doubly-fed induction generator in which a feedback linearization method is enabled and further provides a control device for a doubly-fed induction generator in which a feedback linearization method is embedded, characterized in that the control device divides and measures positive sequency components and negative sequency components from stator voltage and current, rotor voltage and current, and signals of stator magnetic flux and rotor magnetic flux of the doubly-fed induction generator.

Abstract: A control device for a vehicle AC generator, in which a part can be shared even when electrical configuration positions of field coils of rotors of generators are different, is obtained. Switching elements connected in series to the field coil in order to control a field current; and a control signal processing unit, in which information as to whether the field coil is connected to the high potential side or connected to the low potential side is inputted, one of the high potential side terminal and the low potential side terminal is selected on the basis of the inputted information, a control signal is outputted, and ON/OFF control of the switching element is performed to control the field current of the field coil, are provided.

Abstract: A double fed induction generator (DFIG) system and controller are presented in which the rotor side converter is preloaded with one or more initial values for resuming regulated operation to counteract transients upon deactivation of the crowbar protection circuit to provide grid fault ride through.

Abstract: A system for directly and instantaneously controlling the exciter of a generator. A voltage error calculator calculates a voltage error of output voltage of the generator which is regulated by an instruction voltage and a time constant. A switching signal generator generates switching signals in response to the voltage error. An exciter controller controls the exciter in response to the switching signals. Thus, the system can induce the maximum response characteristic of a power converter only by setting the time constant of a controller without a complicated design for determining gains of the controller. Further, the system can considerably inhibit overshoot from occurring in a transient response state.

Abstract: A power converter that interfaces a motor requiring variable voltage/frequency to a supply network providing a nominally fixed voltage/frequency includes a first rectifier/inverter connected to a stator and a second rectifier/inverter. Both rectifier/inverters are interconnected by a dc link and include switching devices. A filter is connected between the second rectifier/inverter and the network. A first controller for the first rectifier/inverter uses a dc link voltage demand signal indicative of a desired dc link voltage to control the switching devices of the first rectifier/inverter. A second controller for the second rectifier/inverter uses a power demand signal indicative of the level of power to be transferred to the dc link from the network through the second rectifier/inverter, and a voltage demand signal indicative of the voltage to be achieved at network terminals of the filter to control the switching devices of the second rectifier/inverter.