33results about How to "Continuous current" patented technology

An electronic ballast for driving a gas discharge lamp includes an EMI filter, a bridge rectifier coupled to a DC bus without a conventional electrolytic capacitor, a passive valley fill circuit built as a network having 4 charge/discharge energy storage capacitors and 9 diodes (4C9C), and a resonant DC to AC high frequency inverter for powering gas discharge lamp. The 4C9D circuit divides the rectified peak voltage by four and the low output voltage of the circuit is used to provide continuous lamp operation. The result is a ballast having substantially improved power factor, total harmonic distortion, and current crest factor. The electronic ballast is provided with a dimming capability from a TRIAC based wall dimmer.

The invention relates to a standard Z source three-level T-shaped inverter and an SVPWM method thereof. A topology has boost features identical to boost features of a standard Z source network three-level NPC inverter, however, few switching elements are utilized, and efficiency is high. Compared with a three-level T-shaped inverter, functions of boost and voltage reduction of the topology can be achieved, direct connection of an upper bridge arm and a lower bridge arm is allowed, reliability is improved remarkably, dead time is eliminated, and waveform distortion is prevented. Compared with a Z source three-level diode clamped inverter, current at an input end is continuous, ripple waves are small, and the input end does not need to be connected with a large-capacitance array set in parallel. Compared with a standard Z source two-level inverter, output voltage has neutral point electric potentials, therefore, high frequency harmonic waves are small, a required filter is small, a switching frequency can be reduced, and switching loss is less. The SVPWM method is adopted to control the inverter, so that switching frequencies are decreased, switching loss is reduced, and harmonic contents of the output voltage are reduced.

The invention provides a rigid contact net expansion joint, which belongs to the field of rail transit equipment and solves the problems that the existing expansion joint has low compensation amount to cause high total manufacturing cost and the like. The rigid contact net expansion joint is arranged between two bus bars. The rigid contact net expansion joint is characterized by comprising a fixed joint and a movable joint which can conduct electricity; the fixed joint and the movable joint are used for fixing with the connecting end of one of the bus bars respectively; a guide piece with electric conductivity for connecting the fixed joint and the movable joint is arranged between the fixed joint and the movable joint; the fixed joint is fixed with the guide piece; the movable joint can move along with the guide piece; and a contact line 1 for transmitting current to an electric system of a train is fixedly arranged on the guide piece. The rigid contact net expansion joint is a plug-in expansion joint, and the adjacent two bus bars and the expansion joint are arranged on the same straight line, so the expansion joint is favorable for improving the utilization rate of the bus bars, equivalently improving the length of an anchorage section, and has large compensation amount.

The invention provides a temperature control method and a temperature control system to solve the problem that the temperature control circuit is of large volume in the prior art. The method comprises the following steps: collecting the current temperature of a controlled object; if the current temperature is higher than a preset temperature, outputting a first PWM control signal to cool the controlled object; judging whether the temperature of the controlled object can reach the preset temperature; if the temperature of the controlled object can reach the preset temperature, cooling the controlled object constantly; if the temperature of the controlled object cannot reach the preset temperature, enabling the duty ratio of the first PWM control signal to be 100%, and controlling the output voltage of a DC voltage regulator module to cool the controlled object; if the current temperature is lower than the preset temperature, outputting a second PWM control signal to cool the controlled object; judging whether the temperature of the controlled object can reach the preset temperature; if the temperature of the controlled object can reach the preset temperature, cooling the controlled object constantly; and if the temperature of the controlled object cannot reach the preset temperature, enabling the duty ratio of the second PWM control signal to be 100%, and controlling the output voltage of the DC voltage regulator module. The scheme ensures that a heating/cooling device works with high efficiency.

The invention relates to an electronic throttle control simulation experiment system. The overseas research of the electronic throttle control system (ETCS) has over twenty-year history, the products prepared by manufacturers are beginning to be put on the market largely and the current generation of the electronic throttle products has been launched. The system of the invention comprises a control circuit, wherein the control circuit comprises a signal acquiring and processing circuit, a MCU, a power drive circuit, a DC motor control driver, an accelerator pedal position sensor (PPS) and an electronic throttle position sensor (TPS); the accelerator pedal position sensor and the electronic throttle position sensor are used to separately input the accelerator pedal control signal and feed back the throttle position signal, the A/D converter of the MCU converts an input analog signal to a digital signal, after the control algorithm calculates control quantity, the control signal is output from a high-speed outlet (HSO) and an I/O port, the DC motor driver outputs the power drive signal to control the rotation of the DC motor, thus realizing the control of the opening of the throttle. The invention is used in the electronic throttle.

The invention discloses a temperature control system device, and relates to the field of temperature control equipment. The temperature control system device mainly comprises a thermoelectric power generation piece, an electromagnet and an armature; the hot end of the thermoelectric power generation piece is arranged at a position to be detected; the thermoelectric power generation piece is in close communication with the electromagnet, and the electromagnet is aligned with the driving end of the armature; the driven end of the armature is provided with a control element connected with an external circuit in an insulating mode; when the hot end of the thermoelectric power generation piece senses that the temperature in the position to be detected reaches the set temperature, the electromagnet provides a current to reach a set requirement, and the electromagnet attracts the driving end of the armature to move; and the driven end of the armature also moves to enable a control element switch connected with a contact external connection circuit to be opened or closed or adjusted; and simple structure, low cost, wide regulation range, high control precision and low electric energy consumption are achieved.

The invention provides a cascaded voltage lifting quasi-Z source converter including a DC input power supply Vin, a first inductor (L1), a first diode (D1), a first capacitor (C1), a second capacitor (C3), a second diode (D2), a second inductor (L2), a third inductor (L3), a third capacitor (C3), a third diode (D3), a fourth diode (D4), a fourth capacitor (C4), a fourth inductor (L4), a fifth diode (D5), a fifth inductor (L5), a switch (S), an output capacitor (Cout), and a load. The cascaded voltage lifting quasi-Z source converter has a high voltage gain compared with a Boost converter and a conventional quasi-Z-source converter, and is suitable for the cases of non-isolated high-gain DC voltage conversion.

A power supply system uses improved Class G amplifier architecture for high bandwidth operation with low distortion. The power supply system switches between multiple power supply rails, depending on the signal level handled by the power supply system. The lowest usable supply rail voltage is chosen to minimize power dissipation in the output driver, thus optimizing efficiency. Each supply rail has an associated driver capable of sourcing current to the amplifier output. When a supply rail is selected, its associated driver is enabled and other driver(s) not associated with the selected supply rail are disabled via separate disable control signals. The disabling of the deselected driver may be delayed until current above a predetermined threshold is sensed at the output of the enabled driver. In addition, the frequency of switching between the power rails may be limited via various means designed to limit distortion in the power supply system.

The electrical saver for single-phase motors comprises a main circuit and a control circuit. The main circuit comprises a bridge rectifier QL1. The single-phase motor is connected in series with the input end of the bridge rectifier. The output end of the bridge rectifier is connected with a first inductor L1 and a transistor T1 in series and a second inductor L2 and a transistor T2 in series. Thecontrol circuit comprises a square-wave oscillator and a frequency regulator. The transistor T1 and the transistor T2 are alternately turned on under the control of the square-wave oscillator. The frequency regulator controls the oscillation frequency of the square-wave oscillator according to the current signal. When the oscillation frequency increases, the terminal voltage of the single-phase motor decreases, and vice versa. The electrical saver has the advantages that the voltage of the single-phase motor is adjusted by the current signal of the motor, the output power of the single-phasemotor is matched with the load, and the waste of electric energy is avoided; During voltage regulation, the first inductor L1 and the second inductor L2 alternately have current passing through them,the current of single-phase motor is continuous, and the harmonic component is small, which can greatly reduce the pollution to the power network.

The invention discloses a large-scale wind power generation system applying a contact electrification technology. The large-scale wind power generation system comprises a plurality of power generationmicro units, a circuit system and a case, the power generation micro units and the circuit system are arranged in the case, and the circuit system is connected with the power generation micro unit; each power generation micro unit comprises an upper substrate, an upper electrode, a lower electrode and a lower substrate which are sequentially arranged from top to bottom. A vibration film layer isconnected between the upper electrode and the lower electrode, and the vibration film layer can vibrate up and down and is in contact with the upper electrode and the lower electrode in the up-down vibration process; a plurality of elastic vertical walls are arranged between the upper electrode and the lower electrode; the circuit system comprises a plurality of rectifying circuit systems and an external circuit system, and the rectifying circuit systems convert alternating current excited by wind power into direct current; and the plurality of rectifying circuit systems are connected in series or in parallel by an external circuit system. The large-scale wind power generation system applying the contact electrification technology is simple in structure, low in dead weight and high in power generation efficiency, and the cost of the power generation system is reduced.

The invention provides a wind-solar hybrid controller and system with continuously-controllable output power. The controller comprises a fan; a three-phase rectifier bridge circuit which is connected with the fan; an energy storage battery of which the positive electrode and the negative electrode are connected with the positive end and the negative end of the three-phase rectifier bridge circuit respectively and which is used for storing electric energy; and a switching direct-current boost circuit which is connected in parallel with the three-phase rectifier bridge circuit and the energy storage battery respectively and is used for controlling the input current of the energy storage battery and realizing continuous controllability of the input current. The wind-solar hybrid system comprises the wind-solar hybrid controller, a power load and a battery control module, wherein the battery control module is used for controlling the charging current value of the energy storage battery according to the practical situation of the energy storage battery. Through adoption of the wind-solar hybrid controller and system, the effects of completely controllable current and continuous current of the energy storage battery are achieved, and the SOC (State of Charge) utilization ratio of the energy storage battery is increased greatly. Meanwhile, the service life of the energy storage battery is prolonged.

The invention discloses a high-voltage high-capacity power electronic switching station device which comprises a metal shell and a power device press-fitting module unit arranged in the metal shell. Each power device press-fitting module unit comprises an upper bidirectional switch valve string and a lower bidirectional switch valve string which are connected in series through a short-circuit copper bar, and the requirements for high-voltage and large-capacity output are met. A voltage-sharing resistor RA3 in the A-phase upper bidirectional switch and a voltage-sharing resistor RA4 in the A-phase lower bidirectional switch are arranged between the A-phase upper bidirectional switch and the A-phase lower bidirectional switch, so that the two voltage-sharing resistors which are connected in series bear the same voltage stress in a static state; a voltage-sharing resistance insulating plate is arranged between the upper bidirectional switch valve string and the lower bidirectional switch valve string so as to enhance the electrical insulation performance between the two.