98results about How to "Reduce voltage fluctuations" patented technology

A system and method for generating a mask layout file to reduce power supply voltage fluctuations in an integrated circuit are disclosed. The method includes analyzing a pattern in a mask layout file to identify a region in the pattern to add one or more decoupling capacitors. Once the region is identified, a feature located in the identified region is moved based on a design rule from a first position to a second position in the mask layout file to create a space in the identified region. The decoupling capacitors are automatically placed in the space in the identified region.

A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

A renewable energy-based hybrid bi-directionally interactive DC traction power supply system includes two traction substations. Each substation includes transformers, rectifiers, bidirectional AC-DC converters, a DC bus, a catenary, a steel rail and a section post. A DC bus between two adjacent traction substations is provided with a DC renewable energy system constructed by an electric vehicle charging-discharging system, a distributed generation and more than one low voltage DC microgrid. The DC renewable energy system is connected to the DC bus between two adjacent traction substations through a high voltage DC bus, thus a DC circular microgrid being formed in a power supply section post. The electric vehicle charging-discharging system is formed by more than one bidirectional DC-DC charging-discharging equipments which are intended for in connection with the power batteries of the electric vehicle. The renewable energy-based hybrid bi-directionally interactive DC traction power supply system of the invention realizes effective usage of distributed generation and recycling of electric locomotive braking energy, reducing DC voltage fluctuation, thus improving reliability of the DC traction power supply system.

The invention relates to a building photovoltaic grid connected system which comprises a plurality of photovoltaic buildings accessed into a power distribution grid through a plurality of access points, and is characterized by comprising an energy storage station and a power-adjustable photovoltaic power station, wherein an electric energy quality coordinated control system and a plurality of electric energy quality adjustment devices are used for adjusting and controlling electric energy quality input into a plurality of low voltage systems; power distribution grid relay protection devices, anti-islanding protection devices and counting measurement and control devices are arranged in a plurality of low voltage systems; and the anti-islanding protection devices and the counting measurement and control devices are arranged at eahc access point of the photovoltaic buildings. By adopting the building photovoltaic grid connected system, short-time power fluctuation in a power distribution grid region can be relieved, and the stability of a power grid can be improved; furthermore, the harmonic content and the voltage fluctuation degree are reduced, and the quality of electric energy is controlled; the power distribution grid relay protection devices and the anti-islanding protection devices ensure security of equipment and safety of human; and the counting measurement and control devices are distributed for different systems, so that automatic and intelligent running management is realized.

A device for controlling vehicle power generation that controls duty cycle of an excitation winding in a vehicle power generator and controls an output voltage from the vehicle power generator to a predetermined value includes a power generation controlling circuit that, when the output voltage from the vehicle power generator is less than the predetermined value, gradually increases the value of a gradual excitation duty and gradually increases the excitation current, the gradual excitation duty being a limit value for increasing and decreasing an excitation drive duty intermittently controlling the electrification of the excitation winding, and in an opposite situation, gradually decreases a value of the excitation drive duty and gradually decreases the excitation current. The power generation controlling circuit changes the rate at which the value of the gradual excitation duty is decreased.

The invention discloses a method for smoothing output power of a wind power station by utilizing an energy storage system. In the method, not only wind power is introduced to predict or rectify the output power of the wind power station, but an improved self-adaptive filtering algorithm is applied. Since the output power of the wind power station is rectified by predicting the wind power, the change rate of the output power of the wind power station is decreased, and the output power of the wind power station can meet standards to inject into a power grid. By employing the self-adaptive filtering algorithm, regarding to the input power in different time, time weight coefficient in an adaptive filtering structure can be automatically calculated according to the input, so that the defect that different input cannot correspond to different filtering time constant by utilizing a low pass filter smoothing method in the past can be overcome. After the smoothing method is employed to smooth the output power of the wind power station, the output voltage of the wind power station is kept stable, fluctuation and flicker of the power grid voltage is reduced, harmonic pollution is reduced and accidents are reduced.

The present invention provides a driving circuit for a vibration apparatus which drives an object using a vibration wave generated by an electro-mechanical energy conversion element is equipped with an electrical resonance circuit, and which is capable of reducing harmonic components of an alternating voltage applied to an electro-mechanical energy conversion element. The electrical resonance circuit includes an electrostatic capacity of the conversion element, plural inductors connected in series with the conversion element, and a capacitor connected at one end between the plural inductors and connected in parallel with the conversion element. The electrical resonance circuit has at least two resonance frequencies including a first frequency and a second frequency and satisfies the relation:f1<fd<f2where f1 is the first frequency, f2 is the second frequency, and fd is a frequency of an alternating voltage.

A direct current switch-off device comprises an on-state current branch circuit and a current commutating and breaking unit which are connected in parallel. The on-state current branch circuit has a mechanical switch (S) and a current transfer module which are connected in series. The current commutating and breaking unit comprises a bridge-type branch circuit and a current-breaking branch circuit. The current-breaking branch circuit and two bridge arms of the bridge-type branch circuit are connected in parallel. The current-breaking branch circuit comprises a nonlinear resistor (RI) and a valve group consisting of fully-controlled devices connected in series. The nonlinear resistor (RI) and the valve group are connected in parallel. Two ends of each fully-controlled device in the valve group are connected in parallel with a buffering and reclosing circuit.

The invention provides a reactive voltage coordinated control method for an extra-high-voltage DC converter and near-field substation and belongs to the technical field of automatic voltage control ofpower systems. According to the method, when each automatic voltage control cycle arrives, whether the DC converter station is in a fault state after unipolar or bipolar blocking is checked, if the converter station is in the fault state, the emergency control of a near-field substation is performed; if the converter station is in a normal operation state, the operation trend of the converter station is determined, and corresponding control strategies are generated for different time periods where the active power of the converter station is located. According to the method, the coordinated control of extra-high-voltage and extra-high-voltage near-field substations is achieved, the repeated switching of reactive power devices in the near-site substation during the process of adjusting a converter station DC active power transmission capacity and the frequent switching of converter station reactive power devices are avoided, and the grid voltage stability and voltage quality are improved.

A liquid crystal display panel of the active matrix drive type is disclosed. Each pixel is provided with an storage capacitor, wherein capacitors for stabilizing the voltage are added to the common storage capacitor bus line that applies a predetermined potential to the storage capacitor bus lines provided for each of the rows to absorb noise that mixes into the storage capacitor bus lines through parasitic capacitances, thereby to decrease fluctuation in the voltage of the storage capacitor bus lines and to prevent the occurrence of display unevenness and crosstalk. Capacitors Ccs for stabilizing the voltage are added to a common storage capacitor bus line (vertical Cs line) 5 that applies a predetermined potential (storage capacitor bus line voltage Vcs) to the storage capacitor bus lines (horizontal Cs lines) 4 provided for each of the rows to form a common side of the storage capacitors Cs formed in each of the pixels. The capacitors Ces are formed by utilizing the common storage capacitor bus line (vertical Cs line) 5. The capacitors Ccs may be formed in the MOS structure.

The invention discloses an active power distribution network reactive voltage optimization method coordinated with multiple active management means. According to the invention, a global optimization-local adjustment two-stage reactive voltage optimization strategy is adopted. Specifically, according to the operation scheme of the invention, the optimized comprehensive satisfaction degree of the network loss and the voltage deviation is adopted as a target, and elements longer in regulation time scale, such as an on-load tap-changer, a capacitor bank, a contact and sectional switch and the like, are optimized. After that, a minimum voltage volatility index is adopted as a target. Moreover, a model is optimized and solved based on the application of the improved harmony search algorithm. Finally, through the analysis of examples, the reasonability and the superiority of the reactive voltage optimization method are verified.

An EL light-emitting element is driven digitally to reduce power consumption using a pixel having three transistors and two capacitors. A reset transistor for diode connection writes the threshold voltage of the drive transistor onto a coupling capacitor. The data voltage plus threshold voltage is then written onto the gate of the drive transistor. This reduces the amplitude of the data voltage required, further reducing power consumption.

A multilayer capacitor includes: a dielectric element; a pair of first internal conductors with same polarity disposed in the dielectric element to be adjacent to each other while being separated from each other by the dielectric layer; first leadout portions led out from the pair of first internal conductors respectively, one being provided for each of the first internal conductors; a pair of second internal conductors with same polarity disposed in the dielectric element to be adjacent to each other while being separated from each other by the dielectric layer; and second leadout portions led out from the pair of second internal conductors respectively, one being provided for each of the second internal conductors, wherein the first leadout portion and the second leadout portion led out respectively from the first internal conductor and the second internal conductor disposed adjacent to each other are led out to substantially the same positions in side faces facing each other of the dielectric element, respectively. Therefore, a multilayer capacitor capable of reducing equivalent series inductance to reduce voltage fluctuation of a power source of a CPU is obtained.

Even when a slave cylinder is operated by driving an electric motor simultaneously with the start of the reduction of regenerative braking force at a time (t3) at which the vehicle speed drops below a shift start vehicle speed and switching from regenerative braking to hydraulic braking is performed, the rise of hydraulic braking force is delayed by the ineffective stroke of the slave cylinder, and therefore a temporary drop in the total braking force of the regenerative braking force and the hydraulic braking force occurs. However, by eliminating the ineffective stroke of the slave cylinder by slightly driving the electric motor in advance at a time (t2) at which the vehicle speed drops below a shift preparation start vehicle speed, the temporary drop in the total braking force of the regenerative braking force and the hydraulic braking force is prevented from occurring at the time of the switching, so that a reduction in brake feeling can be prevented.

A power inverter of the type used with hybrid electric vehicles having a circuit board with a power layer having a first and second section which are electrically separated using slits from each other on the power layer. A control circuit is connected to and powered by the first section of the power layer while a switching power supply is connected to and powered by the second section of the power layer. An electromagnetic filter is electrically connected between the sections of the power layer. This electromagnetic filter blocks high frequency noises of the type generated by the switching power supply while enabling the sections to be maintained at the same DC voltage level. Optionally, a ferrite covering is provided around a current bus bar of the power inverter to contain magnetic fields generated by current flow through the bus bar.

The purpose of the present invention is to provide a power source device of simple configuration, capable of reducing the voltage fluctuation when switching a power source mode between a parallel power mode and a serial power mode. The power source device comprises: a power source main body (40) having a first secondary battery (41) and a second secondary battery (42); a power-mode switching means for switching the power source device between a parallel power mode, a serial power mode, and a second power source solo mode; a first inverter (10); and an inverter connection mode switching means for switching the power source device between a first connection mode in which the power source main body (40) is connected to the first inverter (10), and a second connection mode in which the first inverter (10) is connected in series to the power source main body (40) while the power source main body (40) is in the second power source solo mode. In the case of switching the power mode from the parallel power mode to the serial power mode, the connection mode is switched to the first connection mode and the first motor generator (110) is actuated as a motor, after which the power mode is switched to the second power source solo mode and the connection mode is switched to the second connection mode so that the power-mode switching means switches the power source mode to the serial power mode after the second secondary battery (42) and the first inverter (10) as the power source have been connected in series.

To provide a display device which can realize multi-gray scale display by reducing voltage fluctuation of a pixel, a display device includes a plurality of source signal lines, a plurality of gate signal lines which is provided so as to intersect with the source signal lines, and a pixel electrode to which a signal voltage of the source signal line is applied through a transistor including an oxide semiconductor, which is provided near an intersection portion of the source signal line and the gate signal line; in which in the pixel electrode which is provided between a pair of the adjacent source signal lines, edge portions thereof overlap with edge portions of the source signal lines and an overlapped area with one of the source signal lines is substantially equal to an overlapped area with the other source signal line.

A continuous-time sigma-delta analog-to-digital converter includes a first integrator stage to integrate a difference between a first differential signal derived from a differential analog input signal and a second differential signal derived from a quantized output signal, a quantizer and a low pass filter. The first integrator stage has a differential operational amplifier, first, second, third, and fourth input resistors, and a first pair of integrating capacitors. The differential analog input signal is received at first and second input nodes of the converter. The first and third input resistors are coupled in series between the first input node and a first input of the operational amplifier. The second and fourth input resistors are coupled in series between the second input node and a second input of the operational amplifier. The first and second input resistors are coupled to the third and fourth input resistors, respectively.

In a liquid crystal display device, a pixel matrix is divided into a plurality of pixel regions in unit of pixel column. The pixel matrix is driven so that video signals having the same polarity are written into every divided pixel regions and video signals having different polarities are written into adjacent pixel regions during a vertical period during which signals of one screen are written and the polarity of the video signals is alternately changed every vertical period.

The invention discloses a power flow control method of a flexible multi-state switch connected to a distributed power supply. The method comprises the following steps: 1, constructing a power model ofthe flexible multi-state switch connected to the distributed power supply and a mathematical model of a voltage source type converter of each port; 2, calculating the load rate of each feeder line before the flexible multi-state switch is accessed and the load rate required to be balanced after the flexible multi-state switch is accessed, and deriving the active power adjusted by the connected flexible multi-state switch port voltage source type converter; 3, calculating the input active power of the distributed power supply allocated to each feeder line according to the active capacity ratioof each feeder line; 4, calculating the total active power output to each feeder line by the flexible multi-state switch connected to the distributed power supply. According to the invention, the load active power imbalance among the feeder lines can be adjusted, and the active power input by the distributed power supply is optimally distributed, so the power fluctuation caused by the access of the distributed power supply to a single feeder line can be reduced, and the intermittent energy consumption level is improved.

A method for reducing output image noise for thin film field effect transistor liquid crystal displays, proposes a scheme to dynamically change the output force adjustment of the source drive device S-Driver, reduces the voltage fluctuation of C1, reduces the MLCC vibration of C1, and truly improves the noise problem . The present invention adopts a device that can detect the screen and a source driver device that can change the driving capability. The device for detecting the screen is attached to the inside of the TCON. It only needs to make a five-point judgment on a screen, and each point is 5X5 pixel size or above, used to judge whether the picture is a noise picture. The drive capability of the SD can be adjusted inside without increasing the cost, and there is no need to develop an additional SD device. The TCON detection screen can easily control the SD. We only need to connect the control output pin of TCON with the SD input pin LP1, LP2. The utility model has the advantages of simple structure, good noise regulation effect, convenience and effectiveness.