Abstract: There are presented various embodiments disclosed in this application, including methods and systems of arranging permanent magnets to switch from a first configuration designed for a first torque output to a second configuration designed for a second torque output.

Abstract: An electric generator comprising a rotor with permanent magnets, configured for rotating about a rotation axis; a stator comprising at least one magnetic yoke with arms extending axially inside or outside of the rotor so as to be adjacent to a radial inner or outer side, respectively, of the rotor; wherein the arms of the at least one magnetic yoke are circumferentially distributed so as to form a slot between each pair of adjacent arms, each slot and each arm showing a width. The widths of the arms and/or the widths of the slots have different values distributed along the circumference. The invention is also directed to a valve comprising the electric generator equipped with a turbine wheel for being driven by a flow of gas in the valve.

Abstract: A 2-phase bipolar step motor has a rotor and a stator, the rotor having a plurality of equally spaced rotor poles of alternating north and south magnetic polarities, and the stator having at least eight stator poles extending radially from a stator yoke and terminating in pole shoes interacting radially across an air gap with the rotor poles to cause the rotor to rotate step-by-step when windings around the stator poles are driven by a succession of energized states of the stator. The stator poles divided into four equal groups having a specified drive phase A or B, adjacent poles of a group having alternating drive polarities of the same drive phase A and ?, or B and B. Adjacent poles in the same group are separated by a center-to-center angle one-half of the rotor tooth pitch or up to 20% larger. Adjacent poles of different groups have a larger separation than that between poles of the same group.

Abstract: A moving coil brushless motor including an actuator having a stator and a rotor. The stator includes a cylindrical array of permanent magnets. The rotor includes a coil assembly having a plurality of coils interposed between a stator back plate and the permanent magnet array. The coil assembly rotates relative to the array of permanent magnets. A center shaft is disposed to rotate about a longitudinal axis. A cylindrical transformer is disposed within an interior space circumscribed by the stator back plate and includes a primary side and a secondary side. The primary side includes a primary coil and the secondary side includes a secondary coil magnetically coupled to the primary coil. Primary electronics are in communication with secondary electronics attached to the center shaft. The secondary electronics are configured to receive power from the secondary coil and to provide current to the actuator.

Abstract: A power conversion device may perform model-referenced power processing for multiple heterogenous power nodes. The power conversion device includes interconnects that couple power nodes to power converters. The power converters may include a sparse set in which the number of power converters is dependent on the model of the power source heterogeneity. The sparse set performs power processing on the power from the power node to facilitate provision of a target power at a port of the power conversion device.

Abstract: An isolated gate driver has a first portion in a first voltage domain and a second portion in a second voltage domain. The first and second portions are coupled by an isolation communication channel. The isolated gate driver transmits across the isolation communication channel a serial word containing first drive strength information and simultaneously transmits gate information with the serial word across the isolation communication channel. The gate information indicates a state of a gate signal for a transistor coupled to the second portion of the isolated gate driver. A demodulator circuit demodulates a signal containing the gate information and the drive strength information transmitted across the isolation communication channel in the serial word. A gate signal output circuit coupled to the demodulator circuit supplies the gate signal based on the gate information with a drive strength of the gate signal being based on the drive strength information.

Abstract: There is provided a semiconductor device that includes a switch terminal; a ground terminal; an output switch connected between the switch terminal and the ground terminal and configured to be switchable between a first on-resistance value and a second on-resistance value higher than the first on-resistance value; a detection circuit configured to detect a short-circuit abnormality of the switch terminal by monitoring a switch voltage that appears at the switch terminal in a predetermined detection period; and a controller configured to perform a pulse-drive of the output switch by setting the output switch to the second on-resistance value in the detection period, continuously perform the pulse-drive of the output switch by setting the output switch to the first on-resistance value if the short-circuit abnormality of the switch terminal is not detected, and forcibly stop the pulse-drive of the output switch if the short-circuit abnormality of the switch terminal is detected.

Abstract: A power conversion unit includes a plurality of semiconductor modules, a gate drive circuit, a first substrate having a flat plate shape, and a second substrate having a flat plate shape. The first substrate has a first surface facing a bottom plate of a casing accommodating the semiconductor modules and the gate drive circuit, and a second surface on an opposite side to the first surface. The second substrate is arranged above the first substrate in parallel with the second surface. The semiconductor modules are mounted on the first surface. The gate drive circuit is formed on a surface of the second substrate on a side that does not face the second surface. The power conversion unit further includes a connector provided on the second surface and connected to a surface on a side facing the second substrate.

Abstract: A discharge device is provided. The discharge device discharges an internal power of an electronic device. The discharge device includes a voltage regulation circuit, a charge storage circuit, a control signal generator and a discharge path. The voltage regulation circuit regulates the internal power to a regulated power. The charge storage circuit stores the regulated power. The control signal generator is configured to receive the regulated power and an external power, enabled according to the regulated power, and generating a control signal in response to a voltage level of the external power. The discharge path is configured to receive the internal power, and turned on according to the control signal to discharge the internal power.

Abstract: A current going through the first power semiconductor is sensed by a first and a second current derivative sensing means, the current going through the second semiconductor is sensed by a third and a fourth current derivative sensing means, when the current going through the first power semiconductor increases, the first current derivative means providing a positive voltage and the second current derivative means providing an opposite negative voltage, when the current going through the second power semiconductor increases, the third current derivative means providing a positive voltage and the fourth current derivative means providing an opposite voltage and the system reduces the voltage on the gate of the first power semiconductor if the first and third current derivative means provide voltages of same sign and reduces the voltage on the gate of the second power semiconductor if the second and fourth current derivative means provide voltages of same sign.

Abstract: An electromagnetic interference reducing circuit is provided. A first random number generator generates a plurality of first random number signals each having a plurality of triangular waves. Each of the triangular waves has a plurality of steps. The first random number generator generates a plurality of first random numbers and modulates each of the first random number signals according to the first random numbers. The first random number generator repeatedly counts, repeatedly removes, or does not count time of the steps of each of the triangular waves of each of the first random number signals according to one of the first random numbers. A first oscillator generates a first oscillating signal. A motor controller circuit controls a plurality of switch components of a motor respectively according to the first random number signals based on the first oscillating signal.

Abstract: A voltage converter circuit includes a capacitor having a first end selectively connected to an input power source through a first input switch and a second end selectively connected to the input power source through a second input switch, and a single inductor configured to generate an output voltage in response to a voltage of a node between the single inductor and the first input switch, selectively connect the input power source through the first input switch at the node, and connect the first end of the capacitor at the node.

Abstract: A charge pump apparatus including a first charge pump system, a second charge pump system, a switch transistor, and a voltage regulation circuit is provided. The first charge pump system converts a first supply voltage into a first boost voltage. The second charge pump system converts a second supply voltage into a second boost voltage. The switch transistor is coupled to the first charge pump system and the second charge pump system, and outputs an output voltage according to the second boost voltage. The switch transistor includes a control terminal receiving the second boost voltage, a first terminal receiving the first boost voltage, and a second terminal outputting the output voltage. The voltage regulation circuit controls the second charge pump system according to the output voltage to adjust the second boost voltage so that the output voltage approaches to a target output value.

Abstract: A voltage regulator includes a first control circuit and a first voltage adjusting circuit. The first control circuit receives an output voltage and generates a first control signal according to the output signal. The first voltage adjusting circuit is coupled to the first control circuit, receives the first control signal, and adjusts the output voltage according to the first control signal.

Abstract: A circuit portion comprises a DCDC converter that provides current from an output to a plurality of loads. Channel logic circuitry is configured to provide current from the output of the converter to each load according to a cyclical sequence, wherein each cycle has a duration that is divided equally into a plurality of time slots. The channel logic circuitry is configured to provide current to each load for one or more discrete time slots. The number of time slots is greater than the number of loads so that at least two output loads receive current for different numbers of time slots in a cycle.

Abstract: A circuit portion comprises a DCDC converter that is configured to charge and discharge an inductor according to a duty cycle to provide current to an output load. A duty module is configured to determine the duty cycle such that the DCDC converter will output a target current. A duty limiter module is configured to cause the inductor to discharge early if the determined duty cycle exceeds a threshold.

Abstract: The circuits and methods described herein provide technical solutions for technical problems facing power driver circuits. To reduce or eliminate effects associated with a gate capacitance discharge current and inconsistent effective Vbias, the discharge process may be split into two phases. During a first phase, the transistor gate charge is drained into ground through a large path gate. The ground (GND) features a very low impedance, hence the resulting ?Vbias(t)|phase_1 is negligible even for high discharge currents. The transistor gate node voltage (Vgate) is constantly monitored, and the discharge process switches from the first phase to the second phase when Vgate transgresses a bias voltage threshold based on the target value of Vbias. To switch from the first phase to the second phase, the current path into GND is cut by switching its path gate to an OFF state, and an alternative path is enabled between transistor gate charge and Vbias.

Abstract: This disclosure includes novel ways of implementing a power supply that powers a load. More specifically, a power supply includes a controller. The controller controls operation of a first power converter stage and a second power converter stage to convert an input voltage into an output voltage. For example, the first power converter stage is operative to receive an input voltage and convert the input voltage into an intermediate voltage. The second power converter stage such as a transformer-less switched-capacitor converter is coupled to the first power converter stage. The second power converter stage receives the intermediate voltage and converts the intermediate voltage into an output voltage to power a load.

Abstract: An apparatus includes a controller that monitors an error voltage indicating a difference between an output voltage and a setpoint voltage. Based on the monitored error voltage, the controller generates modulation adjustment signals including a frequency adjustment signal and an ON-time adjustment signal. The controller modulates a pulse width modulation signal of a first power supply phase in accordance with both the frequency modulation adjustment signal and the ON-time adjustment signal.

Abstract: A switching converter circuit comprises an inductive circuit element; a driver switching circuit configured to provide energy to the inductive circuit element to generate an output voltage of the switching converter circuit, the output voltage having an alternating current (AC) signal component and a direct current (DC) signal component; a current sensing circuit configured to generate a current sense signal representative of inductor current of the inductive circuit element, wherein an output of the current sensing circuit is coupled to a bias circuit node; and a dynamic bias circuit configured to apply a dynamic bias voltage to the bias circuit node, wherein the dynamic bias voltage includes an AC component that tracks the AC signal component of the output voltage.

Abstract: A flyback converter and an electronic device are provided. A second end of a first secondary winding in a first secondary winding module of the flyback converter is coupled to a first electrode of a first output capacitor and a first output terminal, a first end is coupled to a cathode of a first diode, and an anode of the first diode is coupled to a second electrode of the first output capacitor. A first electrode of a second output capacitor in a second secondary winding module is coupled to the second electrode of the first output capacitor, a second electrode is coupled to a second output terminal, an anode of a second diode is coupled to a second end of the second secondary winding, a cathode is coupled to the first electrode of the second output capacitor.

Abstract: A galvanic isolator circuit and method provide for galvanically isolating and current limiting a power source from a load. A direct current (DC) input voltage (“vin”) and an input current (“iin”) are received. A full- or half-bridge rectifier is switched to synthesize a first alternating voltage waveform that magnetically couples through a transformer to induce a second alternating voltage waveform with galvanic isolation from the first alternating voltage waveform, preventing potentially-faulted load from a source. The second alternating voltage waveform is rectified to produce a direct current (DC) output voltage (“vo”) having output current (“io”) through more than one drive transistor or diode. The more than one primary-side drive transistor is current limited to reduce or prevent brown-out, black-out, or protective race conditions in the non-faulted portions of DC power generation systems and DC distribution electrical power systems.

Abstract: A system and method of fault detection based on a detailed waveform analysis is presented for transient and steady-state fault operation of 3-? DAB converter. Main symptoms of the converter during normal and fault conditions have been identified and a unique pattern in DC bias of phase currents under fault mode is noted. The logic-based fault diagnosis scheme is used to detect the fault and identify the faulty transistor.

Abstract: Systems or methods of the present disclosure may provide for operating a programmable fabric including multiple programmable elements organized into a number of power domains that utilize a common voltage within the respective power domains. A current sensor senses a current of the programmable fabric. When the sensed current has crossed a threshold, the programmable fabric changes the number of power domains.

Abstract: A power conversion system applied to a solid state transformer includes a DC link, a plurality of capacitors, and a plurality of power conversion module assemblies. The plurality of capacitors is coupled in series between a positive bus and a negative bus of the DC link. Each of the power conversion module assemblies has a plurality of DC conversion modules. In any of the power conversion module assemblies, input sides of the DC conversion modules are connected in series to form two input ends of the power conversion module assembly, and output sides of the DC conversion modules are connected in parallel to form two output ends of the power conversion module assembly. Each of the plurality of power conversion module assemblies is correspondingly connected to each of the plurality of capacitors.

Abstract: An electronic device has a primary loop circuit that includes a main circuit causing a current to flow in a loop shape; and a secondary loop circuit that is disposed to face the primary loop circuit at a predetermined distance, and causes an induced current generated by a magnetic field generated in the primary loop circuit to flow in a loop shape.

Abstract: The present invention relates to a positively-charged body for a triboelectric generator and a triboelectric generator including the same. More particularly, the present invention relates to a positively-charged body based on a two-dimensional material including silicon oxide, and to a triboelectric generator including such a positively-charged body. Thus, a conventional manner in which the positively-charged body is mainly composed of a metal thin film or polymer is not used, but the positively-charged body is made of the silicon oxide and the two-dimensional material. Thus, charge generation efficiency of the generator via contact between the positively-charged body and a negatively-charged body may be dramatically enhanced.

Abstract: The invention relates to an energy harvesting and self-cleaning system based on graphene aerogels and its preparation method, which a layer of metal collector is sputtered on both sides of the freeze-dried graphene aerogel by magnetron sputtering; the graphene aerogel with collector is fixed on the side and bottom of the substrate in series and/or parallel connection, and then is put into the electrolyte to get the target system. The system provides a new idea for mechanical energy harvesting. Firstly introduced aerogels into the field of mechanical energy harvesting. In addition, the system can not only collect mechanical energy, but also absorb oil and other impurities in the ocean, playing the role of ocean cleaning. The energy collection system formed by single aerogel can produce ˜220 mV open circuit voltage in Sodium Chloride Solution or organic electrolyte, and generate 2 W/kg power density.

Abstract: Provided is a novel actuator that can easily achieve movement with multiple degrees of freedom. An actuator includes a flexible electrode, a first base electrode disposed to face the flexible electrode on the Y-axis and provided with a first insulating layer on an opposite face, a second base electrode disposed to face the flexible electrode on the X-axis and provided with a second insulating layer on an opposite face, and a first output member and a second output member adapted to be displaced according to deformation of the flexible electrode. A first space is formed between the first insulating layer and the flexible electrode, in which the flexible electrode deforms toward the first insulating layer by an applied voltage. A second space is formed between the second insulating layer and the flexible electrode, in which the flexible electrode deforms toward the second insulating layer by an applied voltage.

Abstract: This application relates to simulation equipment, and more particularly to an apparatus and method for simulating a line running state of magnetic levitation. The apparatus includes a levitation-guidance mechanism, a moving mechanism and a magnetic guideway fluctuation simulated mechanism. The levitation-guidance mechanism is configured to detect a force on a single Dewar of a maglev train to be simulated. The moving mechanism is configured to move the levitation-guidance mechanism. The magnetic guideway fluctuation simulated mechanism is arranged below the levitation-guidance mechanism, and is configured to apply a variable force to the levitation-guidance mechanism. The variable force is configured to simulate a constantly-variable electromagnetic force applied to the levitation-guidance mechanism by a real track.

Abstract: A power tool includes a housing, a brushless motor disposed inside the housing, and a controller. The controller is configured to receive power-off signals and power-on signals. Upon receiving a power-on signal, the controller is further configured to receive a time signal indicative of a time interval from the last power-off signal to the current power-on signal. The controller is further configured to determine whether the time interval is greater than or equal to a first time threshold and less than a second time threshold, and brake the motor before start-up if the time interval is greater than or equal to the first time threshold and less than the second time threshold.

Abstract: A system for controlling a plurality of motors includes: a variable frequency drive (VFD) configured to control at least one property of the motors, the VFD having a current interruption rating that is greater than a continuous current rating of all of the plurality of motors combined; a bus electrically connected to the VFD; and a plurality of protection modules, each protection module including: a motor overload device electrically connected to a particular one of the plurality of motors; and a switching relay in series with the motor overload device, the switching relay configured to connect the protection module to and disconnect the protection module from the bus. A state of the switching relay determines whether the protection module is electrically connected to the bus, the VFD is configured to control the state of the switching relay, and the switching relay has a current interruption rating that is less than the continuous current rating of the particular one of the plurality of motors.

Abstract: The purpose of the present invention is to improve the reliability of a power conversion system while reducing the size. In addition, the purpose of the present invention is to reduce noise. This power conversion system has a first power converting device that supplies power to a first motor and a second power converting device that supplies power to a motor different from the first motor, wherein the first power converting device and the second power converting device are each provided with a power converter for converting the power to be supplied to the motors, and a control unit for controlling the power converter, and the first power converting device is provided with a transformer unit for supplying power to the control units, and the transformer unit of the first power converting device supplies power to the control unit in the second power converting device.

Abstract: An electric tool includes: a motor; an attachment unit to receive a tip tool attached thereto; a drive control unit to control the motor; a number of revolutions detection unit; and a torque detection unit. The number of revolutions detection unit detects a number of revolutions of a first detection target shaft. The torque detection unit detects a load torque of a second detection target shaft. The drive control unit detects, based on the number of revolutions and load torque detected, an unstable behavior of at least one of the tip tool, the first detection target shaft, or the second detection target shaft and either decelerates, or stops running, the motor when detecting the unstable behavior.

Abstract: A determination method and apparatus for a brushless direct current counter-electromotive force zero crossing point threshold and a storage medium, the method includes detecting counter-electromotive force zero crossing point time intervals of two adjacent sectors of a brushless direct current electric motor to obtain at least two first time intervals; utilizing the obtained at least two first time intervals to determine errors of a counter-electromotive force zero crossing point; converging the determined errors of the counter-electromotive force zero crossing point to obtain a counter-electromotive force zero crossing point threshold correction increment; and utilizing the obtained counter-electromotive force zero crossing point threshold correction increment to determine a counter-electromotive force zero crossing point threshold.

Abstract: Systems and methods for extracting motor operational state parameters from an electric motor for improved motor control and motor fault or failure detection are discussed. An exemplary system includes an excitation circuit to apply a drive voltage to an electric motor, and a processor circuit to measure a resulting winding current, extract a current waveform by oversampling the winding current in an entire PWM frame at a sampling rate higher than the PWM frequency, and fit the current waveform in the PWM period to a parametric model. The processor circuit can determine a motor operational state parameter using one or more of the applied drive voltage or the parametric model of the winding current.

Abstract: A motor driving circuit includes a wiring pattern formed in a circuit board, which is configured such that electrical current flowing into a motor flows through the wiring pattern; and a current measurement circuit configured to measure an amount of electrical current flowing through the wiring pattern, based on an amount of voltage drop occurring in response to flowing of the electrical current. The motor driving circuit includes a drive unit configured to adjust a current measurement value measured by the current measurement circuit, based on first adjustment data that compensates for variation in resistance of the wiring pattern caused by an individual difference in the circuit board, and to drive the motor based on an adjusted current value which is the adjusted current measurement value.

Abstract: An inverter for driving a motor that has a switchable connection of windings and drives a load element having a periodically varying load torque is provided. The inverter is controlled so that an output torque of the motor follows the periodic variation of the load torque. The inverter is controlled so that a current flowing through the motor is zero during a period including a minimum torque phase at which the load torque is at or near a minimum value. The connection is switched while the current flowing through the motor is zero. It is possible to switch the connection of the windings while the motor is rotating, and avoid an increase in apparatus size.

Abstract: A driving apparatus includes: an inverter unit generating a three-phase alternating-current voltage from a direct-current voltage in accordance with a drive signal based on a voltage command and outputting the three-phase alternating-current voltage to a permanent-magnet motor, the permanent-magnet motor including a permanent magnet; a current detection unit detecting a motor current flowing through the permanent-magnet motor; and a control unit generating the voltage command to control an operation of the inverter unit and estimating a temperature of the permanent magnet to perform a protection operation on the inverter unit on the basis of the motor current and an overcurrent protection threshold.

Abstract: The invention relates to a motor control method for a vehicle. The method includes: determining that a motor control unit (MCU) malfunctions; monitoring an output alternating current frequency of an electric motor; and controlling, based on the output alternating current frequency, the electric motor to switch between an active short circuit state and a safety pulse off state. The invention further relates to a motor control circuit for a vehicle, a motor drive system, and a vehicle.

Abstract: A motor drive unit for driving a motor of a motorized window treatment may comprise software-based and hardware-based implementations of a process for detecting and resolving a stall condition in the motor, where the hardware-based implementation is configured to reduce power delivered to the motor if the software-based implementation has not first reduced the power to the motor. A control circuit may detect a stall condition of the motor, and reduce the power delivered to the motor after a first period of time from first detecting the stall condition. The motor drive unit may comprise a stall prevention circuit configured to reduce the power delivered to the motor after a second period of time (e.g., longer than the first period of time) from determining that a rotational sensing circuit is not generating a sensor signal while the control circuit is generating a drive signal to rotate the motor.

Abstract: The object of the present invention is to use the high temperature thermal power stored in the fluid bed in conjunction with thermophotovoltaic (TPV) technology. TPV technology requires thermal emitters at high temperature (>600° C.) to produce electricity from thermal radiation. TPV thermal emitters are located immersed in or exposed to a hot particles fluidized bed, protected by suitable layers of high temperature resistant material, like ceramic or refractory walls. Such high temperature fluidized bed, will provide thermal power to the TPV cells, to produce electricity.

Abstract: A transportation pathway, such as a railway or roadway, has a plurality of poles supporting electrical wires. The poles extend in a line parallel to the transportation pathway. In a railway, the poles support a power cable to supply power to an electric train or tram. In a roadway, the poles have electrical wires for street lights. Solar panels extend between the poles and provide power to the train, tram or street light, or support an outlet for recharging electric vehicles. The power generated by the solar panels can be used to supplement or replace the power provided through the poles. Power not used in this manner can be stored in a battery or sent into the electric grid. The solar panels can be retrofit onto existing systems.

Abstract: A system includes a photovoltaic module having photovoltaic cells, each having a width, and a roofing shingle having an exposure zone and a headlap zone. A plurality of slots extends from the exposure zone to the headlap zone and define tooth portions. A first one of the tooth portions has a first side defined by a first slot and a second side defined by a second slot adjacent to the first slot. The first tooth portion has a first width that is the photovoltaic cell width multiplied by a first positive integer. A second tooth portion has a first side defined by a third slot and a second side defined by a fourth slot adjacent to the third slot. The second tooth portion has a second width that is the photovoltaic cell width multiplied by a second positive integer different than the first positive integer.

Abstract: A system includes a plurality of photovoltaic modules, each having a mat with an edge and a spacer with an edge, the edge of the mat being attached to the edge of the spacer. The spacer includes a plurality of support members and a solar module mounted to the support members. Each of the support members includes a ledge. The solar module and the ledge form a space therebetween. The space is sized and shaped to receive an edge of a solar module of another of the photovoltaic modules. The spacer of one of the photovoltaic modules overlays the mat of another of the photovoltaic modules.

Abstract: Systems and methods of use of movable shading devices, are disclosed. In some example implementations, the system can include one or more movable shading devices, where the one or more movable shading devices are configured to be selectively moveable, based on control by a programmable controller, with respect to an external surface of a building or house, where the external surface of the building or house includes at least one wall surface and at least one roof surface, to conserve at least one of cooling energy use associated with the building or house and/or heating energy use associated with the building or house.

Abstract: Autonomous cleaning robot comprises rear cover and front cover 120. Robot 100 comprises Beale 130. Robot 100 uses two or more, three or more, for more, six or more, or eight or more wheels 130. The exemplar depicted in FIG. 1-a shows the robot with two brush assemblies 140, but the cleaning nature of robot 100 only requires a single brush assembly 140. Assembly 140 comprises brush 150 brush motor 160, and various other components that connect brush assembly 142 chassis of robot 100. Brush assembly 140 connects to the chassis of robot 100 and in some exemplars has two pieces a front chassis 230 and rear chassis 220. Brush motor 160 drives the rotation of brush 150 through a transmission 161.

Abstract: A step-up conversion module includes a first step-up circuit, a second step-up circuit, a first unidirectional conduction element, and a second unidirectional conduction element. The first step-up circuit includes a first input loop composed of a first inductor and a first switch unit. The second step-up circuit includes a second input loop composed of a second inductor and a second switch unit. The first inductor and the second inductor form a coupling inductor with a common core. The first unidirectional conduction element blocks a first reverse current induced by the coupling inductor to the first input loop. The second unidirectional conduction element blocks a second reverse current induced by the coupling inductor to the second input loop.

Abstract: Circuits integrated or integrable with a photovoltaic panel to provide built-in functionality to the photovoltaic panel including safety features such as arc detection and elimination, ground fault detection and elimination, reverse current protection, monitoring of the performance of the photovoltaic panel, transmission of the monitored parameters and theft prevention of the photovoltaic panel. The circuits may avoid power conversion, for instance DC/DC power conversion, may avoid performing maximum power tracking to include a minimum number of components and thereby increase overall reliability.

Abstract: A portable solar powered pool heater comprising a housing, a hose, a controller, a solar panel and at least one leg having a first position for supporting the housing above a surface, and a second position disposed inside of the housing. This heater can include a hinge, wherein the leg comprises a leg that is coupled to the housing via the hinge. In one embodiment the leg comprises a telescoping leg having a first leg, and a second leg wherein said second leg is telescoping inside of the first leg.