15 results about "Variable-voltage power supply" patented technology

Embodiments of the present disclosure include adaptive bias control of cascode drivers in envelope tracking power amplifier devices, systems, and methods. In some aspects, a wireless communication device is disclosed that includes a power amplifier. The power amplifier may include a driver stage configured to receive a variable voltage supply signal, and a power amplifier stage following the driver stage. In some embodiments, the driver stage includes a cascode gate bias circuit configured to receive a first signal that is based on the variable voltage supply signal; and a cascode amplifier stage comprising a first field effect transistor (FET) and a second FET in a stacked configuration. The cascode gate bias circuit may be further configured to adaptively convert the first signal into a bias signal for a gate of the first FET. The power amplifier stage may be configured to generate an amplified signal based on the intermediate output.

The application relates to a line voltage power failure detection circuit and a detection method thereof. The line voltage power failure detection circuit comprises a variable voltage power supply module, a main power switch module, a power failure detection module, a first switch control module and a second switch control module. The power output end of the variable voltage power supply module is connected with the signal collection end of the power failure detection module. The signal output end of the power failure detection module is connected with the signal input end of the main power control module. The first signal output end of the main power control module is connected with the controlled end of the first switch control module. The second signal output end of the main power control module is connected with the controlled end of the second switch control module. When the commercial power supply stops, the main power switch module controls the first switch control module to be closed and the second switch control module to be opened, so that the battery or the capacitor is discharged, the capacitor is prevented from being kept in a high-voltage state for a long time, and the risk of electric shock is reduced.

The embodiment of the invention provides shale oil yield increase testing equipment and method. The equipment comprises a true triaxial confining pressure assembly used for forming an accommodating bin for accommodating a to-be-tested experimental rock sample and pressurizing the experimental rock sample to simulate formation pressure; the transformer assembly comprises a graphite electrode and a variable voltage power supply, and the graphite electrode is fixed in the accommodating bin and is used for heating the experimental rock sample; the variable-voltage power supply is connected with the graphite electrode and used for providing electric energy for the graphite electrode; the gas adjusting assembly is connected with the containing bin and used for adjusting gas parameters in the containing bin; the environmental parameter sensing assembly is connected with the accommodating bin and is used for acquiring environmental parameters in the accommodating bin; and the component analysis assembly is connected with the accommodating bin and is used for obtaining a product obtained after the experimental rock sample generates a carbonization channel under a preset condition and is subjected to in-situ cracking through normal-pressure alternating current heating, and analyzing the components of the product. The equipment and the corresponding test method are used for achieving the effect of improving the test accuracy.

The utility model discloses a testing device for testing an RIM module of a diesel locomotive, which comprises the RIM module and a case, a relay module, a resistance measuring unit, a transistor output module, an NPN output module, a switching power supply, a variable voltage power supply module and a display unit are arranged in the case, the RIM module is electrically connected with the input end of the relay module, and the input end of the transistor output module is electrically connected with the input end of the NPN output module. The output end of the relay module is electrically connected with the input end of the resistance measuring unit, the input end of the transistor output module and the input end of the NPN output module, and the output end of the resistance measuring unit is electrically connected with the input end of the NPN output module and the switching power supply. The output end of the transistor output module and the output end of the NPN output module are electrically connected with the display unit, the switching power supply and the NPN output module respectively. According to the testing device, the cost can be effectively reduced, the service life of the RIM module of the HXN5 type diesel locomotive is reasonably prolonged, and it is guaranteed that the RIM module is convenient to maintain.

The utility model relates to the technical field of power supply, specifically discloses a kind of vehicle-mounted electrical equipment's variable-voltage power supply system, including vehicle battery, overload protector, main distribution box, transformer, variable-voltage distribution box, multiple voltage switching matrix switch and on-off power matrix switch, the vehicle battery is connected with the main distribution box electricity by the overload protector, the main distribution box is connected with the transformer and multiple voltage switching matrix switch electricity respectively, the transformer is connected with the multiple voltage switching matrix switch electricity by the variable-voltage distribution box, the multiple voltage switching matrix switch is connected with vehicle-mounted electrical equipment electricity by the on-off power matrix switch.The variable-voltage power supply system of vehicle-mounted electrical equipment provided by the utility model is convenient to use, voltage switches efficiently, low in cost, reduces connecting wire harness, and safety is improved.

Embodiments of the present disclosure include adaptive bias control of cascode drivers in envelope tracking power amplifier devices, systems, and methods. In some aspects, a wireless communication device is disclosed that includes a power amplifier. The power amplifier may include a driver stage configured to receive a variable voltage supply signal, and a power amplifier stage following the driver stage. In some embodiments, the driver stage includes a cascode gate bias circuit (202) configured to receive a first signal that is based on the variable voltage supply signal; and a cascode amplifier stage (204) comprising a first field effect transistor (Mi) and a second field effect transistor (M2) in a stacked configuration. The cascode gate bias circuit (202) may be further configured to adaptively convert the first signal into a bias signal for a gate of the first field effect transistor (Mi).

The present disclosure relates to a driver circuit for driving a capacitive transducer. The circuit comprises an output stage circuit (330) configured to receive an input signal and drive the capacitive transducer (340) to produce an output signal; a variable voltage power supply circuit (320) configured to output a supply voltage to power the output stage circuit, wherein the supply voltage output by the variable voltage power supply circuit varies based on the input signal; a supply capacitor (326, 328) to receive the supply voltage output by the variable voltage power supply circuit; a storage capacitor (360); and a circuit to transfer charge between the storage capacitor and the supply capacitor (400).

An electric motor for a pump includes an AC line-in node for receiving AC power supplied to the electric motor. The electric motor includes a current sensor coupled to the AC line-in node and measures current supplied to the electric motor. The electric motor includes a motor controller configured to convert the AC power supplied to a variable frequency variable voltage power for driving the electric motor at a normal output value. The motor controller includes a microcontroller and an inverter. The microcontroller is coupled to the current sensor and receives a measured value of the current supplied to the electric motor, determines the measured value is above a threshold, and transmits a control signal representing a reduced output value. The inverter receives the control signal and generates the variable frequency variable voltage power to reduce output from the electric motor according to the reduced output value.

A potential-compensating electrostatic shield that prevents the occurrence of abnormal electric fields within a housing is provided. [Solution] The potential-compensated electrostatic shield 1 comprises an outer housing 2 which is a conductor, an inner housing 3 which is a conductor arranged inside the outer housing 2 and electrically insulated from the outer housing, a detection unit 4 which detects the potential of the inner housing 3 or a physical quantity corresponding to said potential, and a variable voltage power supply 5 which applies a potential difference between the outer housing 2 and the inner housing 3, and the variable voltage power supply 5 controls the potential difference based on the potential detected by the detection unit 4 or the physical quantity corresponding to said potential.

To provide a measuring method capable of simply measuring a contact potential and a relative dielectric constant by utilizing an existing device.SOLUTION: In the Kelvin probe measurement method, a variable voltage power source is electrically connected between a sample to be measured and probe electrodes, distances between the sample to be measured and the probe electrodes are periodically changed, and a current I1 flowing between the sample to be measured and the probe electrodes or a signal voltage I1 after amplifying the current V1 is measured. A contact potential VC is obtained from a voltage V applied by a variable voltage power source when a current I1 or a signal voltage V1 becomes 0, and a relative dielectric constant ε is obtained from ε = ε ' * α / α ' using a slope α of a characteristic curve drawn by a peak-to-peak value Vpeak-to-peak of the signal voltage V1 with respect to the voltage V applied by the variable voltage power source and a slope α ' of a characteristic curve obtained by measuring a reference sample made of a material having a known relative dielectric constant ε ' under the same conditions as those for obtaining the characteristic curve.SELECTED DRAWING: Figure 1

An electric motor for a pump is provided. The electric motor includes a motor controller configured to convert alternating current (AC) power supplied to a variable frequency variable voltage power for driving the electric motor at a motor output according to a commanded motor output. The motor controller includes an inverter configured to generate the variable frequency variable voltage power according to the commanded motor output and a microcontroller coupled to the inverter. The microcontroller is configured to control the inverter to operate at a first switching frequency when the motor output is less than a threshold motor output and control the inverter to operate at a second switching frequency when the motor output is greater than the threshold motor output, wherein the second switching frequency is less than the first switching frequency.

The present invention provides a variable voltage power supply device and a variable voltage power supply system, the power supply device comprises a stator and a rotor, the rotor rotates relative to the stator; the rotor comprises a rotating body and a plurality of permanent magnets, the plurality of permanent magnets are arranged on the rotating body, the stator comprises a magnetic core, a plurality of first windings and a plurality of second windings, a plurality of winding mounting blocks are arranged on the magnetic core, the plurality of winding mounting blocks are evenly arranged in a radial shape along the circumference of the magnetic core, the plurality of permanent magnets are respectively arranged one by one opposite to the plurality of winding mounting blocks, a first winding and a second winding are respectively arranged on a winding mounting block, a first connection line for input voltage is connected to the first winding, and a second connection line for output voltage is connected to the second winding. With the above structure, the rotor rotates to make the second winding generate current and output voltage, so that by controlling the voltage output in the second winding, the output voltage can be adjusted in real time, so that the voltage transformer can be transformed within a certain value range.

The application provides a DC motor feedback speed regulation system of analog quantity detection control and belongs to the technical field of motor control. The application comprises a base, a variable voltage power supply arranged on the base and used for providing power supply for the DC motor feedback speed regulation system, and an upper plate arranged above the base; a control execution module used for controlling the operation of a DC motor MA, a rotating disc, the DC motor MA used for driving the rotating disc to rotate, and a generator MF rotationally connected with the DC motor MA are arranged on the upper plate; three groups of load inertia adjusting devices with the same structure and a laser speed measuring instrument with a speed measuring reflective sticker are arranged on the rotating disc. The application can experiment the knowledge of classical control theory, and can also actively change the rotational inertia of the load, so as to facilitate the research on the tracking effect of the DC motor feedback speed regulation when the rotational inertia is changed.

A power supply system 1 includes: a variable voltage power supply 7 that outputs power of a variable voltage E1 from a pair of secondary-side input / output terminals 72p and 72n; a first power line 21 and a second power line 22 that connect the pair of secondary-side input / output terminals 72p and 72n and a load 4; a first switch unit 31 that is provided on the first power line 21; a third power line 23 that connects both ends of the first switch unit 31; and a bypass line 25 that connects the pair of secondary-side input / output terminals 72p and 72n, a first DC power supply 38 is provided on the third power line 23 to output DC power, and a bypass diode 33a is provided on the bypass line 25 to allow an output current of the first DC power supply 38.

The application relates to the field of soil desalination, and particularly discloses a power-on method and a power-on device for soil desalination. The device comprises a power supply, a plurality of current distributors and a plurality of electrode groups. The method comprises the following steps: device preparation; single round power-on: according to the size of the detection current of each group, the distance between the positive and negative electrodes of power-on is adjusted; multiple rounds of power-on: the initial power-on positive and negative electrode spacing of the next round of power-on is smaller than that of the previous round of power-on. According to the change of the current with time in the electric desalination process, the distance between the electrodes is adjusted to realize the adjustment of the current, the electric desalination process is kept under suitable current conditions at all times, the desalination efficiency is improved, the desalination time is shortened, the waste of electric energy is reduced, and the energy consumption is reduced. Compared with the mode of adjusting the voltage by using a variable voltage power supply, the power-on method provided by the application adopts a constant voltage direct current power supply, and a power supply with continuously adjustable voltage is not needed, so that the cost of the power supply is reduced.