19 results about "Dc converter" patented technology

A DC-based power system including: an AC power distribution system for providing AC power to a first node and a second node; a first converting system coupled to the first node that converts AC power to DC power and outputs the DC power to a first distributed bus bar; a second converting system coupled to the second node that converts AC power to DC power and outputs the DC power to a second distributed bus bar; a first set of DC/DC converters that steps down the DC power from the first distributed bus bar to a first stepped down DC voltage; a second set of DC/DC converters that steps down the DC power from the second distributed bus bar to a second stepped down DC voltage; and a critical load distribution system that is powered by both the first stepped down DC voltage and the second stepped down DC voltage.

The invention discloses a PWM/PDM double-mode modulation selecting circuit and a double-mode modulation method, which mainly solves the problem that the prior DC/DC converter is not high in average conversion efficiency within a heavy-load range. The whole circuit comprises a bias circuit, a band gap reference voltage source, an error amplifier, an isolation common-source follower, an oscillator, an integrator, a mode judgment comparator, a control comparator, a latch and a driving buffer, wherein the mode judgment comparator and the latch are connected between the output end of the error amplifier and the control end of the oscillator; the magnitude comparison of load current is converted into voltage comparison through the relation of duty cycle and triangular wave; and when the load current is larger, the circuit selects a PWM modulation mode otherwise the circuit selects a PDM modulation mode when the load current is smaller. Under the condition of guaranteeing the performance of the DC/DC converter, the invention improves the average conversion efficiency in a load change interval, and is applicable to the DC/DC switch converter with great load current change, low requirement on circuit volume and high requirement on conversion efficiency.

Asynchronous rectifier controller is provided on a secondary side of an insulation-type synchronous DC/DC converter and controls the synchronous rectifier transistor. A driver circuit controls the synchronous rectifier transistor. A photo coupler connection terminal is coupled to an input side of the photo coupler. An error amplifier amplifies an error between a voltage detection signal according to an output voltage of the DC/DC converter and its target voltage, and to draw a current according to the error from an input side of the photo coupler via the photo coupler connection terminal.

The invention discloses a multifunction simulation power source used for distributed generation grid connection detection. The multifunction simulation power source is characterized by comprising a photovoltaic array electricity generation character analog module and a fan/micro-gas turbine electricity generation character analog module, wherein the photovoltaic array electricity generation character analog module comprises a rectifying circuit connected with a mains supply, a first DC (direct current)-DC converter connected with the output end of the rectifying circuit and used for providing power for direct current detection equipment, a first DSP (Digital Signal Processor) control circuit and a first human-computer interface connected with the first DSP control circuit; the fan/micro-gas turbine electricity generation character analog module comprises a DC-AC (alternating current) inverter circuit connected with the output end of the first DC-DC converter and used for providing power for alternating current detection equipment, a second DSP control circuit and a second human-computer interface connected with the second DSP control circuit. The simulation power source is capable of simulating the photovoltaic array electricity generation character, the fan electricity generation character and the micro-gas turbine electricity generation character and has the alternating current and direct current output characters.

The invention relates to a three-port DC/DC converter for high-power charging and belongs to the technical field of automobile driving and control. The three-port DC/DC converter solves the problem that a traditional non-isolated buck topology cannot freely and simultaneously realize high-power charging and the control of the free charge-discharge requirements of a battery. An input capacitor is connected in parallel with a voltage source; the positive pole of the voltage source is connected to the drain of a switching transistor Q1; the source of the switching transistor Q1 is connected to the cathode of a diode D1; the anode of the diode D1 is connected to the negative pole of the voltage source; the source of a switching transistor Q2 is connected to the cathode of the diode D1; the drain of the switching transistor Q2 is connected to the cathode of a diode D2; the anode of the diode D2 is connected to the positive pole of a battery; the negative pole of the battery is connected tothe anode of the diode D1; one end of an inductor L1 is connected to the source of the switching transistor Q2; the other end of the inductor L1 is connected to the drain of a switching transistor Q3;the source of the switching transistor Q3 is connected to the anode of a diode D3; the cathode of the diode D3 is connected to the positive pole of the battery; one end of an output capacitor is connected to the drain of the switching transistor Q3; and the other end of the output capacitor is connected to the negative pole of the battery. The three-port DC/DC converter is suitable for automobiledriving and control.

Methods, computer-readable mediums, apparatuses, and systems are provided. For example, a method is disclosed which includes identifying at least one security system function, in a plurality of security system functions, for blocked user access when a keypad is away from a predetermined location; and storing the plurality of security system functions on a processor. In another embodiment a security keypad is disclosed which includes an LCD having a static portion and a dynamic portion; a multiplexing LCD controller coupled to the dynamic portion; a static LCD controller coupled to the static portion; DC/DC converter coupled to the multiplexing LCD controller; a keypad processing unit coupled to the multiplexing LCD controller, the static LCD controller, and the DC/DC converter; and a power supply coupled to the DC/DC converter, the keypad processing unit, and the static LCD controller.

The invention discloses a maximum power output control method suitable for controlling a variable speed wind turbine group through concentrated variable flow. According to n wind turbines which are controlled by the same converter in a concentrated mode and are constant in rotating speed and different in input air speeds, the concentrated converter and overall wind turbine propeller pitch variation mechanisms are controlled in a coordinated mode, and therefore maximum power output of the wind turbine group is achieved. A control objective of the concentrated converter is that the speed of the wind turbine with the higher wind speed approaches to the optimal rotating speed as much as possible and a control objective of the propeller pitch variation mechanisms is that the highest wind energy utilization rate of the wind turbine with the lower wind speed is obtained at the unified rotating speed of the wind turbine group. The optimal calculation method is adopted and the frequency conversion alternating current bus frequency and the overall wind turbine propeller pitch angle which correspond to the maximized output power of the wind turbine group are worked out. The maximum power output control method is suitable for the variable speed wind turbine group controlled by an AC-DC converter in a high-voltage direct current power transmission system and an AC-AC frequency converter in a frequency division power transmission system.

The invention discloses a method and a system for a stability analysis of a DC (Direct Current)/DC converter. The method comprises the following steps of step S1, performing conversion deduction on aDC/DC converter system model to obtain a state-space equation of the DC/DC converter suitable for a stability analysis method of a discontinuous control theory; and step S2, judging an exponential stability of a DC/DC converter system and calculating an exponential convergence rate of the DC/DC converter by use of the deduced state-space equation of the DC/DC converter according to an exponentialstability analysis method of the discontinuous control theory. According to the method and the system for the stability analysis of the DC/DC converter, the DC/DC converter is described by use of thediscontinuous control theory, the system does not need to be linearized when the DC/DC converter is analyzed, the analysis of the system stability is more accurate, and meanwhile an analysis process is simplified.

The embodiment of the invention provides a POE controller and a POE control system; a POE controller adopts a PWM terminal or a DC voltage terminal; the POE controller comprises a POE separator which is used for separating the DC voltage and the data, a DC/DC converter which is connected to the POE seperator, and an LED lamp which is used for converting DC voltage supplied by the POE seperator to DC high voltage and supplying the DC high voltage to an LED lamp driven by the DC voltage; the DC voltage supplied by the POE seperator is converted to the DC low voltage which is supplied to the microprocessor; an LAN module is connected to the POE seperator and the DC/DC converter; the LAN module is used for receiving the data coming from the POE seperator and transmitting the data to the microprocessor; the microprocessor is connected to the DC/DC converter and the LAN module for executing the data coming from the LAN module and generating a corresponding control signal to control the LED lamp.

The invention provides an energy storage management device and an energy storage monitor system, relating to the technical field of energy storage system. The device comprises a controller, an energystorage battery pack, and an AC/DC converter, a DC/DC converter and a charging and discharging loop that are connected with the controller, the energy storage battery pack comprises multiple storage batteries that are connected in parallel, the controller is used for receiving a control signal sent by a system monitor, and triggering on and off the AC/DC converter, the DC/DC converter and the charging and discharging loop, so as to manage charging and discharging of the energy storage battery pack. According to the energy storage management device and the energy storage monitor system, each circuit module can be controlled separately, the storage battery parallel connection manner does not need to ensure the consistency of the storage batteries, the circuit structure is simple, the use ratio of the storage battery is improved, post operation and maintenance are facilitated, the environment is protected, and the working efficiency of energy storage management is improved.

The invention provides a car-mounted low-voltage battery charging method. Firstly, a vehicle controller controls the output current of the DC/DC converter to be I0, the output voltage is U0 to chargethe battery with constant current and constant voltage, if the battery temperature is detected to be greater than the battery alert temperature at some point in time, judging whether the battery temperature at the time is smaller than the battery temperature at the previous time, if yes, calculating a difference T between the battery temperature at that time and the battery temperature at the previous time, and the charging current IPID of the battery is calculated by using T and PID algorithm, after that, the vehicle controller controls the output current of the DC/DC converter to change to IPID, and the output voltage remains unchanged at U0 to charge the battery. If it is detected that the battery temperature is higher than the maximum allowable charging temperature of the battery at acertain time, the charging is terminated; otherwise, the battery temperature is cyclically judged, and different currents are used to charge the battery. The method of the invention is simple and feasible, can improve charging efficiency and avoid excessive temperature of the battery.

The invention relates to a low-input current ripple high-gain soft switching direct current converter, which comprises an input port, a load port, a first switch tube, a second switch tube, a first diode, a second diode, a third diode, an input inductor, a coupling inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor and a load. According to the invention, through complementary control of the two switch tubes, zero-voltage conduction of the two switch tubes and zero-current turn-off of the three diodes can be realized; and the low-input current ripple high-gain soft switching direct current converter has the advantages of high voltage gain, small input current ripple, high conversion efficiency, small switching tube voltage stress and the like, and is very suitable for a non-isolated renewable energy power generation system.

A transformer for a DC-DC converter, such as a resonant converter, is provided. The converter includes a transformer unit that includes at least one winding with a first winding connection and a second winding connection, and a capacitor assembly consisting of at least one capacitor with a first capacitor assembly connection and a second capacitor assembly connection. The capacitor assembly is arranged so as to lie against the transformer unit in order to form an assembly. The capacitor assembly connections are connected to the winding connections via one or more first connection parts in a specified manner with respect to the electric connections. The capacitor assembly connections and/or the winding connections are electrically connected to multiple second connection parts in a specified manner with respect to the electric connections for connecting to a first power module and a second power module.

The invention discloses an analysis device for a power distribution system of a pure electric loader, and the device comprises a power distribution system analysis device body, an AC/DC converter, and a power protector. The power distribution system analysis device body is provided with the AC/DC converter, and the AC/DC converter is connected with the power protector. When the system is in work, the AC/DC converter on the power distribution system analysis device body converts alternating current into direct current firstly, and the power protector protects a power supply. Finally, the device is guaranteed to work stably. Compared with a conventional device, the device provided by the invention is stable in work, is wide in application range, is higher in analysis precision than conventional equipment, is high in analysis speed, and is simple in structure.

The invention discloses an inductance energy storage type isolated DC-DC converter and a control method thereof, and relates to the field of power electronics and power transmission, the inductance energy storage type isolated DC-DC converter comprises a primary side loop, a secondary side loop and a controller, and an inductor is connected between the primary side loop and the secondary side loop. According to the inductance energy storage type isolated DC-DC converter, isolation between input and output of the converter is achieved by means of the electrical isolation characteristic of the semiconductor power device when the semiconductor power device is turned off, electric energy is stored through the inductor, the inductor is charged through the input side, energy of the inductor is absorbed through the output side, and the power semiconductor switches on the input side and the output side are turned on in a time-sharing mode. Time-sharing transfer of energy is achieved, electrical insulation of an input side and an output side can be achieved by combining switching characteristics of a semiconductor device, electrical insulation of output voltage and input voltage can be achieved, buck-boost conversion can be achieved, and an isolation transformer does not need to be used.

The invention relates to an extended adjustment of a control variable for a DC-to-DC converter having a plurality of DC-to-DC converter modules (30-1, 30-2). For this purpose, in addition to the conventional regulation of the individual DC voltage converter module, a further correction variable (K-1, K-2) is determined, which can be added to the regulation variable (R4-1, R4-2). The correction quantity can take into account in particular individual characteristics of the DC voltage converter module, such as component tolerances or the like. For this purpose, correction values suitable for the individual DC voltage converter modules can be determined beforehand and stored in a non-volatile memory. By using these previously stored relationships, the control variables for the individual DC voltage converter modules can be individually adjusted.

The invention discloses a dual-operation-mode DC-DC converter and a DC socket for adaptively controlling output voltage. The dual-operation-mode DC-DC converter comprises a low-voltage DC conversion circuit and a high-voltage DC conversion circuit which are connected in parallel, an output capacitor CO is connected in parallel with the output ends of the low-voltage DC conversion circuit and the high-voltage DC conversion circuit; by comparing the required output voltage with a set threshold, the dual-operation-mode DC-DC converter can be controlled to work in a low-voltage operation mode or ahigh-voltage operation mode. The socket can control voltage output in an adaptive mode, the situation that a household direct-current power supply system is provided with a multi-stage voltage outputsocket is avoided, and the design cost of direct-current household appliances and the design cost of the household direct-current power supply system are reduced on the whole.

The invention discloses a photovoltaic power generation system practical training assessment device, which comprises a photovoltaic power generation circuit (I), a supplementary circuit (II) and a fault debugging panel (III). The device is characterized in that the photovoltaic power generation circuit (1) comprises a solar cell panel (01), a DC/DC converter (02), a DC/AC inverter (03), an inductance filter (04), an AC load (05), a current and voltage detector (06), a synchronous signal detector (07), a TMS320F240 control circuit (08), a drive circuit (09) and an SG3525 control circuit (10), the supplementary circuit (II) comprises a relay, wires are connected between the photovoltaic power generation circuit (1) and the supplementary circuit (2) and between the photovoltaic power generation circuit (1) and the fault debugging panel (3) according to electrical lines, fault points K1 to K5 are arranged in the photovoltaic power generation circuit (1), and the fault points are connectedwith a fault operation switch on the fault debugging panel through the relay of the supplementary circuit. The comprehensive skills of fault searching, fault analysis, fault solving and the like of students in the aspect of a photovoltaic power generation system can be improved.