An apparatus for minimizing self-discharge of a smart battery pack is provided. During initial storage of the smart battery pack (100), prior to be being charged, a self-discharge protection circuit (110) disables smart battery circuitry (130). A minimal current drain is maintained while the smart battery circuitry (130) is disabled. Upon coupling of the smart battery pack (100) to a charger, the protections circuit (110) enables the smart battery circuitry (130). Battery packs having to be shipped with partially drained cells as part of shipping precaution requirements are no longer faced with the additional drainage problem previously caused by the smart battery circuitry (130) during storage.

A semiconductor device for battery control includes a CPU, a first bus coupled to the CPU, a second bus not coupled to the CPU, and a protective function circuit for protecting a battery from stress applied thereto. The semiconductor device also includes a non-volatile memory storing trimming data, a trimming circuit to perform trimming required to allow the protective function circuit to exert a protective function, and a bus control circuit capable of selectively coupling the first bus and the second bus to the non-volatile memory. The semiconductor device further includes a transfer logic circuit which causes, by making the bus control circuit select the second bus, a trimming data transfer path leading from the non-volatile memory to the trimming circuit to be formed and the trimming data stored in the non-volatile memory to be transferred to the trimming circuit without involving the CPU.

A battery pack and an electronic device are disclosed. The battery pack includes a battery for storing electric energy, and a non-contacting discharging unit for receiving the stored electric energy from the battery and for transferring the stored electric energy to a power receiving unit in a non-electrically contacting manner. The electronic device includes a main body and the battery pack. The main body includes a power receiving unit. The battery pack is for mounting to and supplying power to the main body.

The invention relates to a monitoring system for monitoring a state of a door lock mechanism of a door or of a closure of a storage space of a means of transportation, comprising a generator and a sensor/actuator. The generator produces electrical energy from vibration energy, and the sensor detects the state of the door lock mechanism. The sensor uses the kinetic energy that is produced by the actuation of the door lock to generate an electrical signal, which is then transmitted to a microcontroller.

A discharge device actively discharges a main capacitor in an electric-power system of an electric-drive vehicle and comprises a discharge branch of a circuit connected in parallel to the capacitor and including a discharge transistor biased to “conduction” mode when the capacitor must be discharged. A control device is connected to a “gate/base” terminal of and controls the transistor, biasing the transistor to the mode when the capacitor is required to fee discharged. A control transistor maintains the discharge transistor in a “non-conductive” state when the control transistor is in the mode. The control transistor is in the state for the discharge transistor to be in the mode. A safety capacitor is interposed between the terminal and a power supply and charges when the discharge transistor is in the mode, causing a progressive decrease of current at the terminal, until the discharge transistor is biased to the state.

Methods, systems, and apparatus for aggregating electric power flow between an electric grid and electric vehicles are disclosed. An apparatus for aggregating power flow may include a memory and a processor coupled to the memory to receive electric vehicle equipment (EVE) attributes from a plurality of EVEs, aggregate EVE attributes, predict total available capacity based on the EVE attributes, and dispatch at least a portion of the total available capacity to the grid. Power flow may be aggregated by receiving EVE operational parameters from each EVE, aggregating the received EVE operational parameters, predicting total available capacity based on the aggregated EVE operational parameters, and dispatching at least a portion of the total available capacity to the grid.

There is provided a battery module including: a power storage unit storing power; a first authentication unit carrying out first authentication via a first authentication route; a second authentication unit carrying out second authentication via a second authentication route; and a discharging control unit controlling discharging from the power storage unit to an external appliance, wherein the first authentication unit is operable, when the first authentication has succeeded, to share key information to be used in the second authentication with an authentication party for the second authentication, the second authentication unit carries out the second authentication using the key information shared with the authentication party, and the discharging control unit is operable, when the second authentication has succeeded, to permit discharging from the power storage unit.

A battery voltage detector includes, but is not limited to: a voltage detection circuit; and a voltage processor. The voltage detection circuit includes, but is not limited to: a capacitor configured to be charged by a battery cell; a pair of output terminals; an output switch; and a voltage processor. While the capacitor is charged, the output switch is configured to be off-state and insulate the capacitor from the pair of the output terminals. After the capacitor is charged, the output switch is configured to be on-state and connect the capacitor to the pair of the output terminals. The voltage processor is configured to obtain, as a cell voltage, a voltage between the output terminals of the voltage detection circuit while the output switch is on-state. A high-potential output terminal of the pair of the output terminals is connected to a power line via a pull-up resistor.

A method includes steps of dividing resistance R into a physical and chemical resistances Ro and Rp, obtaining corrected open-circuit voltages Vo corresponding to setting currents Ia to Ix, acquiring predicted reaching voltages Va to Vx corresponding to the setting currents Ia to Ix, and creating a current-voltage curve. The corrected open-circuit voltages Vo are obtained to predict available maximum currents I—target in a particular time t2. The predicted reaching voltages Va to Vx are acquired based on corrected physical and chemical resistances Ro and Rp, and the corrected open-circuit voltages Vo. The current-voltage curve is creased based on the setting currents Ia to Ix and the predicted reaching voltages Va to Vx to acquire upper and lower limit voltages Vmax and Vmin, and upper and lower limit currents Imax and Imin at a temperature whereby assigning these limit currents to available maximum currents I—target in charging and discharging operations, respectively.

An charging device includes: capacitors connected in series; a charging unit that charges the capacitors; bypass units, each respectively connects in parallel to each capacitors, wherein each bypass unit causes, when a charged voltage of any capacitor has reached a set voltage, a charging current to bypass the capacitor whose charged voltage has reached the set voltage; and a control unit that controls the charging unit to charge the capacitors in such a manner that, when a charging voltage of the any capacitor has reached the set voltage, the control unit causes the charging unit to reduce the charging current, and if a predetermined period has elapsed since the charging voltage has reached the set voltage, and if a charging voltage of any of the other capacitors has not reached the set voltage after the predetermined period, the control unit causes the charging unit to increase the charging current.

An electricity generation device includes a permanent-magnet electric generator with three or more phase windings each having an output terminal and connected to a neutral point, and bidirectional semiconductor switching circuits capable of interrupting connections between the respective phase windings and the neutral point. Each switching circuit allows current to flow in both directions. A gate signal generation circuit outputs to one of the switching circuits during a period including the time at which the AC voltage excited in the corresponding phase winding turns from positive to negative and during a period including the time at which the AC voltage excited in the corresponding phase winding turns from negative to positive. A startup gate signal output circuit outputs a startup gate signal to all of the bidirectional semiconductor switching circuits when the permanent-magnet electric generator is to be started.

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.

The present embodiments provide a control system and method that is able to automatically start and/or stop a portable engine-driven power source. For example, in one embodiment, a system includes an engine-driven power source having an engine, a compressor driven by the engine, a sensor configured to generate a first signal indicative of a demand for air pressure from the compressor and a second signal indicative of no demand for air pressure from the compressor. The engine-driven power source also includes a controller configured to stop the engine in response to the second signal.

The excitation overcurrent detection unit for the doubly-fed electric machine is provided with a function to determine an excitation current magnitude relationship among three phases. The firing pulse is held to on-state or off-state to cause the largest-current phase and the second-largest-current phase to charge the DC capacitor by the operation of diodes. The conduction ratio of the third-largest-current phase or minimum current phase is controlled according to the detected current value to protect against a possible short-circuit across the DC capacitor. When the voltage of the DC capacitor exceeds a preset value, the voltage is suppressed by operating active or passive power devices.

A rotary electric machine for a vehicle that is capable of starting synchronous rectification through switching elements after having ensured absence of a short circuit fault. The rotary electric machine includes a multi-phase armature winding, a switching element set that includes a plurality of pairs of upper-arm and lower-arm switching elements to form a bridge rectification circuit together with the armature winding, an on/off-timing setter that sets on/off-timing of each switching element, a switching element driver that drives each switching element at the on/off-timing set by the on/off-timing setter; and a synchronous control start determiner that determines timing when an energization period for the upper-arm switching element and an energization period for the lower-arm switching element occur alternately as start timing of the synchronous rectification.

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.

A wind power generator generates power through a rotation of a rotor and is interconnected, and operated with its power generation output previously limited in order to be able to further supply the power to a power system in response to a decrease in system frequency. Thus, a concentrated control system derives a required restricted amount corresponding to a power generation output required to respond to the decrease in system frequency, derives a value by subtracting an amount corresponding to a latent power generation output with which the power generation output can be increased, from the required restricted amount, and sets a restricted amount of the power generation output in each wind power generator to perform the operation with the power generation output previously limited to respond to the decrease in system frequency, based on the above value.

The present invention provides a method and a device for primary frequency regulation based on bang-bang control, the method comprises: obtaining in real-time a power grid frequency of a steam turbine generator set; performing a subtraction operation on a rated power grid frequency and said power grid frequency to generate a power grid frequency difference; performing a dead zone process on the power grid frequency difference according to a dead zone fixed value to generate a frequency difference; performing a frequency difference compensation operation on the frequency difference to generate a frequency difference compensation instruction; and combining an original primary frequency regulation output instruction with the frequency difference compensation instruction and outputting the result to a steam turbine speed regulation system when a selecting switch is 1.

A fault tolerant electrical machine including: a plurality of phases; a detector arranged to detect a fault in at least one of the phases; and a controller arranged to intentionally cause a fault in at least one other of the phases such that the vector sum of the second harmonic power vectors of the remaining phases is zero.

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.

A generator airgap monitoring system includes a first proximity sensor disposed in a first location of a stator and configured to transmit a first signal representative of a first distance between the first proximity sensor and a plurality of rotor poles of a rotor, and a controller communicatively coupled to the first proximity sensor. The controller is configured to derive a first plurality of instantaneous airgaps based on the first signal and to determine a difference between a first instantaneous airgap of the first plurality of instantaneous airgaps and a second instantaneous airgap of the first plurality of instantaneous airgaps. The first plurality of instantaneous airgaps includes a first plurality of measurements of airgaps between the stator and the plurality of rotor poles when the rotor is rotating. The first instantaneous airgap and the second instantaneous airgaps include measurements for respective rotor poles.

An inverter generator used in combination with a motor and an ECU generating a pulse at each predetermined rotation angle of the motor is comprised of: an electric generator driven by the motor configured to generate alternating current electric power; estimating means for estimating an electrical angle of alternating voltage of the alternating current electric power from the pulse, the estimating means being electrically connected with the ECU; a converter configured to convert the alternating current electric power into direct current electric power, the converter electrically connected with the electric generator and the estimating means; and an inverter configured to convert the direct current electric power into alternating current output electric power, the inverter electrically connected with the converter.

A wind energy plant comprising a rotor having blades and a generator driven by said rotor for generating electric energy. The pitch of the blades can be adjusted and a pitch system for adjusting the pitch angle of the blades is provided, which is supplied by a hub power source. An additional electric load is provided on the hub. A pitch power control device is provided which dynamically distributes the power of the hub power source between the pitch system and the additional electric load and further acts on the pitch system such that its power consumption during high-load operation is reduced. Thus, the power consumption of the pitch system during high-load operation can be reduced and additional power provided for operating the additional load. Even large additional loads, such as a blade heater, can be operated in this way, without having to boost the hub power source.

The control system of this floating wind turbine generator is a control system of a floating wind turbine generator in which the control system controls a pitch angle control section by a pitch angle instruction value calculated on the basis of signals detected by a second sensor detecting a relative angle between a nacelle and a tower and a third sensor detecting a yaw angle from a reference position of the tower so that a signal detected by a first sensor detecting wind direction deviation relative to a vertical direction of a rotation plane of wind turbine blades indicates an angle within a predetermined range from the vertical direction of the rotation plane of the wind turbine blades, and controls a yaw driving device by a yaw driving instruction value calculated on the basis of the signals detected by the second sensor and the third sensor.

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.

An electric power generation system (EPGS) employs both a wild-source generator and a variable and/or constant frequency generator. The wild-source generator is coupled to receive mechanical power from a low-pressure spool on an aircraft engine and to generate in response a wild-source output for consumption by voltage and frequency-tolerant loads. The variable and/or constant frequency generator is coupled to receive mechanical power from a high-pressure spool on the aircraft engine and to generate in response a variable and/or constant frequency output for consumption by voltage and frequency-intolerant loads.

An alternator has rectifying module groups. The rectifying module groups form a bridge circuit. The rectifying module groups have a load dump protection judgment section for monitoring an output voltage of rectifying module groups. When the monitored output voltage exceeds a first threshold voltage, the load dump protection judgment section provides to a control section an instruction to turn on MOS transistors in a lower arm of the bridge circuit at a time when a predetermined delay time has elapsed. When a second threshold voltage is lower than the first threshold voltage and the monitored output voltage becomes less than the second threshold voltage after the monitored output voltage exceeds the first threshold voltage, the load dump protection judgment section provides to the control circuit an instruction to turn on the MOS transistors in the lower arm after the MOS transistors are turned off during a predetermined time length.

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.

An electrical machine includes a stator having a main armature winding, an exciter field winding, and a transformer primary winding. A rotor is operatively connected to rotate relative to the stator, wherein the rotor includes an exciter armature winding operatively connected to the exciter armature winding for field excitation therebetween, a main field winding operatively connected to the main armature winding for field excitation therebetween, and a transformer secondary winding operatively connected to the transformer primary winding to form a rotating transformer. A generator control unit is operatively connected to the main armature winding, exciter field winding, and transformer primary winding to control the main armature and exciter field windings based on excitation in the primary winding received from the transformer secondary winding.

An on-demand electric power system for providing on-demand electric power in remote locations. The on-demand electric power system generally includes a protective housing, an engine-generator within the protective housing, a control switch electrically positioned between the engine-generator and an electric load, and a control unit in communication with the engine-generator and the control switch to control operation of the engine-generator along with electrical power to the electric load. The control unit detects when electrical power is required by an electric load and then first starts the engine-generator. After a period of time, the control unit then closes the control switch to provide electrical power to the electric load.

A method for converting heat to electric energy is described which involves thermally cycling an electrically polarizable material sandwiched between electrodes. The material is heated by extracting thermal energy from a gas to condense the gas into a liquid and transferring the thermal energy to the electrically polarizable material. An apparatus is also described which includes an electrically polarizable material sandwiched between electrodes and a heat exchanger for heating the material in thermal communication with a heat source, wherein the heat source is a condenser. An apparatus is also described which comprises a chamber, one or more conduits inside the chamber for conveying a cooling fluid and an electrically polarizable material sandwiched between electrodes on an outer surface of the conduit. A gas introduced into the chamber condenses on the conduits and thermal energy is thereby transferred from the gas to the electrically polarizable material.

This invention is directed to a system that generates a sufficient level of electricity through access to a municipal water supply line to run a furnace during below freezing temperatures. The system includes an inlet that draws water from a water supply line. A first conduit, in communication with the inlet, transports the water into a DC generator that includes an impeller to generate electricity. Water is then routed through a second conduit which then returns the water to the water supply line through an outlet. A solenoid valve may be positioned between the inlet and first conduit which remains closed when the electric grid runs normally but will open during a power outage to supply water to the DC generator. A lithium battery stores power created by the DC generator, which may include a voltage regulator and inverter to convert to DC.

A wind turbine is provided. The wind turbine includes a generator, an output thereof being connectable to a power grid via a power transmission path, the power transmission path comprising a generator side converter coupled to the output of the generator, a grid side converter coupled to the power grid, and a DC link coupled between the generator side converter and the grid side converter. For diverting the generator power, a load dump arrangement is provided which includes at least one resistor, a plurality of switches, and a plurality of electrical connections which electrically connect the at least one resistor to the output of the generator and across the DC link via the plurality of switches. One common and configurable load dump is used for both converter system failures and grid failures. As compared to two separate load dumps for converter failures and grid failures, the single load dump will require a smaller space for a wind turbine. Thus, the weight and size of the power converter system may be reduced.

A magnetic controlled power generator provides a magnetic controlled loading device, power generator and flywheel device to form two independent modules which are easily assembled and disassembled for easy manufacture and maintenance. Besides, the magnetic controlled power generator has simple installation and lightweight components to generate a radial displacement for magnetic flux control, achieving continuous adjustment of the load resistance, thereby having the effect of reducing the cost and weight.

Some embodiments relate to a method of controlling speed of a variable speed generator. The method includes detecting a load of the variable speed generator and determining a target speed for the variable speed generator based on the load supplied by the variable speed generator. The method further includes using a controller to adjust the speed of the variable speed generator based on the target speed. The method may further include correcting the target speed by calculating a correction factor that corrects the target speed based on a voltage produced by the variable speed generator.

A dip in the output voltage of a motor-vehicle alternator, owing to a connecting of a load or a change in speed, is compensated with the aid of an alternator regulator which provides a control signal that has a duty factor and increases the excitation current of the motor-vehicle alternator. After the occurrence of the voltage dip, in a first step, the duty factor of the control signal is increased by a differential amount, and in a subsequent second step, the rate of correction is limited. After the occurrence of the voltage dip, parameters describing the instantaneous working point of the motor-vehicle alternator are determined, and in the first step, the differential amount is set as a function of the working point.

A self-excited alternator for generating electrical energy. The alternator includes a stator, a rotor, and an exciter. The rotor includes conductors which are integrated within the rotor via one of a casting process, a welding process, or a fastening process. The exciter includes a magnet producing a static magnetic field, and a rotatable conductive member coupled to the shaft and electrically coupled to the one or more conductors. The rotatable conductive member is operable to output the direct current to the one or more conductors upon rotation within the static magnetic field, thus exciting the alternator.

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.

A temperature detection device that detects a temperature of a rotor of a motor. The temperature detection device has a current detection unit configured to detect a current value of a current flowing through a winding with which any one of a stator and the rotor of the motor is provided, an iron loss estimation unit configured to estimate an iron loss of the rotor using the current value, and a rotor temperature estimation unit configured to estimate the temperature of the rotor using the iron loss.

According to an embodiment, a method of operating a wind turbine comprising a DC-to-AC voltage converter is provided, the wind turbine being connectable to a grid via the DC-to-AC voltage converter, the method comprising: determining a line voltage of a power line connecting the DC-to-AC voltage converter to the grid; if the determined line voltage exceeds a predefined voltage threshold value, injecting reactive current into the power line, wherein the amount of reactive current injected is chosen such that an output voltage of the DC-to-AC voltage converter is kept within a predetermined voltage range.

A generator includes a permanent magnet generator, an exciter and a main generator mounted for rotation on a shaft. The main generator is configured to produce a voltage output. A generator control unit includes a circuit configured to provide current from the permanent magnet generator to the exciter. A switch is provided in the circuit and is configured to change between open and closed conditions. The switch is configured to flow current in the circuit in the closed condition and interrupt current flow in the open condition. An overvoltage limit controller is programmed to determine an amount of overvoltage of the output voltage exceeding a desired voltage. Either a fixed reference threshold is used or a reference threshold voltage is calculated based upon the duration in over voltage condition, and the switch is modulated between the open and closed conditions according to error between the actual output voltage and the reference threshold voltage to limit the output voltage to the desired reference threshold voltage.

A generator system includes a generator having a stationary portion and a rotating portion. An exciter field winding and a main armature winding are disposed on the stationary portion. An exciter armature winding and a main field winding are disposed on the rotating portion. A frequency demodulator is configured to extract a frequency modulated control signal from the exciter armature winding and to demodulate the frequency modulated control signal to generate a demodulated control signal. The generator includes a main field rotating power converter to selectively control current in the main field winding in response to the demodulated command signal. The generator system includes a generator control unit in electrical communication with the generator to monitor the output voltage at the main armature winding and to output an exciter current including the frequency modulated control signal to the exciter field winding based on the output voltage.

A DC motor assembly (10) with soft starting capability is provided. The assembly (10) comprises a DC motor (12) including an armature (14) and a field winding (16) adapted to be excited separately from the armature; and circuitry configured to controllably increase current flow through the field winding of the DC motor as a function of time during starting of the DC motor.

A method of controlling a generator (110) of an electric drive (104) associated with an engine (102) is provided. The method may determine an operational state of the electric drive (104) based on a speed of the engine (102), and selectively engage one of a map-lookup control scheme (150) and a fixed-theta off control scheme (152) for operating the generator (110) based on the operational state of the electric drive (104).

A system configured for charging and distribution control is provided. The system includes a switching regulator, a control circuit and a first converter. The switching regulator is configured to be selectively operable in one of a first operative state and a second operative state based on a control signal. The first operative state and the second operative state are associated with a maximum level of an alternator output power corresponding to at least one alternator operational feature, at least one alternator operational feature being associated with the alternator output voltage and an alternator speed. The control circuit is configured to generate the control signal based at least on the at least one alternator operational feature. The first converter is configured to generate a first converter output voltage based on the regulated DC output voltage. The first converter output voltage is lower than the regulated DC output voltage.

A power supply system for a motor vehicle includes a generator that includes a rotor having a field coil and a stator having an armature coil; a rectifier that rectifies AC power generated in the armature coil; an excitation control circuit that takes control of a voltage applied to the field coil; a capacitor that is connected to the DC side of the rectifier, and receives and transfers the rectified power; a battery connected to an electric load of the motor vehicle; a DC-DC converter that is connected between the capacitor and the battery and capable of converting unidirectionally or bidirectionally an input DC voltage into any DC voltage; and a selection switch which connects the capacitor or the battery to the excitation control circuit as a power supply source.

The regulator/brush-holder assembly (1) comprises a support (2) and an electrical circuit (5, 6) comprising a regulating element (5) connected by microwires to a trace circuit (6). The electrical circuit further includes a filtering circuit (10) separate from the regulating element and connected by microwires to the trace circuit. According to one particular embodiment, the filtering circuit comprises an insulating substrate (11) and surface-mounted components (C1, C2, S1, S2, V). A ground plane (19) and/or one or more ground pads may be provided for connection to a ground trace of the trace circuit. The filtration frequencies of the filter circuit extend from 100 kHz to 1 GHz.

A method for converting heat to electric energy is described which involves thermally cycling an electrically polarizable material sandwiched between electrodes. The material is heated using thermal energy obtained from: a combustion reaction; solar energy; a nuclear reaction; ocean water; geothermal energy; or thermal energy recovered from an industrial process. An apparatus is also described which includes an electrically polarizable material sandwiched between electrodes and a heat exchanger for heating the material. The heat source used to heat the material can be: a combustion apparatus; a solar thermal collector; or a component of a furnace exhaust device. Alternatively, the heat exchanger can be a device for extracting thermal energy from the earth, the sun, ocean water, an industrial process, a combustion reaction or a nuclear reaction. A vehicle is also described which comprises an apparatus for converting heat to electrical energy connected to an electric motor.

A thermionic generator for converting thermal energy to electric energy includes: an emitter electrode for emitting thermal electrons from a thermal electron emitting surface when heat is applied to the emitter electrode; a collector electrode facing the emitter electrode spaced apart from the emitter electrode by a predetermined distance, and receiving the thermal electrons from the emitter electrode via a facing surface of the collector electrode; and a substrate having one surface. The emitter electrode and the collector electrode are disposed on the one surface of the substrate, and are electrically insulated from each other. The thermal electron emitting surface and the facing surface are perpendicular to the one surface.

A method of operating a converter of a wind turbine for providing electric energy to a utility grid includes determining a grid voltage. If the grid voltage is between a nominal voltage and a first voltage threshold, i.e. higher than the nominal voltage, a normal procedure for lowering the grid voltage is performed. If the grid voltage is above the first voltage threshold, another procedure for keeping the wind turbine connected is performed, wherein the other procedure is different from the normal procedure. Further a corresponding arrangement is described.