60results about How to "Stabilize bus voltage" patented technology

The invention discloses an energy management control method of a photovoltaic energy storage system. The energy management control method comprises a photovoltaic energy storage system configuration method, a concentrated energy storage system control method and a distributed energy storage system control method. Compared with a mixed energy storage structure, the energy management control method adopts a concentrated energy storage and distributed energy storage layered control manner, and global control and partial control can be conveniently and effectively carried out on the photovoltaic energy storage system; a control circuit and a control process are simplified and the control efficiency is improved; by optimizing the concentrated energy storage and distributed energy storage control methods, the photovoltaic utilization rate can be effectively improved and bus voltage is stabilized; and with the adoption of a storage battery grouped control manner, the problems that the data volume is great and an electric charge state of each storage battery is difficult to reasonably determine when single control is adopted are solved. The energy management control method can be widely applied to the distributed photovoltaic energy storage system; and a control manner is simplified, the control efficiency is improved and the photovoltaic utilization rate and the power supply quality are improved, so that the energy management control method has very important application prospects.

The invention discloses a semiconductor device test system and a test method thereof. The test system comprises an upper computer, an oscilloscope, a main control system PLC, a circuit control moduleand a test box body. An automatic tool is arranged in the test box body, a tested piece is placed on the automatic tool, and a test fixture is arranged right above the tested piece. The automatic toolcomprises a driving device, the driving device drives the automatic tool to move so as to drive the tested piece to be connected with the test fixture, and the main control system PLC is connected with the test box body, the test fixture, a main circuit unit and a gate pole driving unit. The upper computer is connected with the oscilloscope, and the oscilloscope is connected with the test box body. The advantages of the present invention are that the semiconductor device test system with a specific testing circuit and a testing system structure is designed, the theory is combined with the practice, and all devices in the system are matched with one another to test the semiconductor device.

The invention provides a large-scale energy storage SOC balance coordination control system and method. The system comprises a first bus, a second bus, a third bus, a fourth bus, at least one photovoltaic power generation unit, at least one wind power generation unit, at least two loads, a first line impedance, a second line impedance, a third line impedance, a fourth line impedance and N lithiumbattery boxes. In order to adjust the charging and discharging power of each battery according to the properties of the batteries with different capacities, the system achieves the purpose that the SOC tends to be consistent, has certain resistance to power grid disturbance caused by frequent load switching, and maintains the stability of each bus voltage. Different reference voltage regulation coefficients are distributed to batteries with different capacities, and the corresponding change ranges are given, thereby achieving the reasonable distribution of the charging and discharging power, reducing the loss of the battery and prolonging the service life of the battery. Meanwhile, the SOC can be kept consistent for a long time through reference adjustment coefficient adjustment when all batteries reach the same SOC.

The utility model relates to an A.C. co-phase traction supply device of railway locomotive based on YN, vd wiring transformer; wherein, the traction transformer is a three-phase to two-phase balancing transformer (T), the wiring method of which is YN, vd. A rectifying inverter (Z) is connected between two outputs (b', c') of the line voltage of the transformer (T) and two outputs (a, x) of the phase voltage of the transformer (T), and the outputs (b', c') of the line voltage and the outputs (a, x) of the phase voltage are the supply ends (V1, V2) of the traction locomotive. Meanwhile, a control device of the rectifying inverter (Z) is connected with the two supply ends (V1, V2) of the traction locomotive. The utility model has the advantages of achieving the co-phase power supply in the whole line of the railway without dividing phases, being stable voltage in each section of the traction transforming station, ensuring that the locomotives can move at high speed when the locomotives are overloading, getting the power in three-phase from the public power network of the power supply system of the traction load of the railway, and eliminating the effect of the traction load of the railway to the power quality of the public power network can be eliminate, which can also be made by the prior traction transformer with low cost and convenient implementation.

The invention discloses an uninterrupted standby power system comprising an uninterrupted power supply, an inversion distribution box, a charge-discharge protection unit and a double-power control cabinet, wherein the inversion distribution box is electrically connected with a load; the charge-discharge protection unit and the double-power control cabinet are electrically connected with an uninterrupted power supply; the double-power control cabinet is electrically connected with a generating set and a commercial power incoming line device; the generating set and the charge-discharge protection unit are in electric connection; and an automatic oil supply device is arranged on one side of the generating set. The power for the load is provided by the uninterrupted power supply when the commercial power is cut or goes wrong, and when the voltage of the uninterrupted power supply is lowered to a protection voltage, the charge-discharge protection unit controls the generating set to charge the uninterrupted power supply, so as to guarantee stable power supply for users; besides, the uninterrupted standby power system has the advantages of small volume of the entire equipment, flexibility in use, light weight, and convenience in both operation and maintenance.

The invention discloses an electric vehicle hybrid energy management system based on adaptive wavelet transformation and a control method thereof. The electric vehicle hybrid energy management systembased on adaptive wavelet transformation comprises a super capacitor, a lithium battery, two DC/DC converters, a drive module, an acquisition circuit and a control module. The control method comprisesthe following steps that firstly, a total reference current required by the load is obtained through voltage loop control; then the adaptive wavelet transform algorithm is used for performing wavelettransform on the total reference current required by the load to obtain a high-frequency current component and a low-frequency current component, wherein the low-frequency current component is takenas a reference current of the lithium battery, and the high-frequency current component is taken as the reference current of the super capacitor; then, a current loop of the control module tracks thereference current of the lithium battery and the super capacitor in real time to realize the real-time distribution of the load demand power. According to the electric vehicle hybrid energy managementsystem based on adaptive wavelet transformation and the control method thereof, the super capacitor is fully utilized, and the lithium battery is effectively protected.

The invention discloses a power supply structure for a stratospheric aerostat. The power supply structure comprises a first power supply unit and a second power supply unit, wherein the first power supply unit comprises a first solar cell array, a first unidirectional DC converter, a first bidirectional DC converter and a first energy storage battery which are electrically connected in sequence; and the second power supply unit adopts an electric connection structure which is the same as the first power supply unit. The power supply structure for the stratospheric aerostat comprises two independent power supply units, and a distributed installation method is adopted to meet the requirement for center-of-gravity regulation of the aerostat; the redundant backup is realized through a controllable parallel connection of the same components of the two independent power supply units, a fault isolation function of a component level and a component backup function between the two power supplyunits are realized, and the reliability of system operation is improved; the power supply structure has various working modes, and bus voltage is guaranteed to remain stable always.

The invention discloses a wind power converter main circuit topological structure with two units of a direct-current bus connected in series. The wind power converter main circuit topological structure with two units of the direct-current bus connected in series comprises a power generator, a positive bus, a negative bus, a transformer connected with an external power grid, a rectification module through which the positive bus and the negative bus are connected, a boosting module and an inversion module. The positive bus and the negative bus are connected in series after being processed by the rectification module, the boosting module and the inversion module, and a neural point is grounded. By means of the design, the wind power converter main circuit topological structure can bear higher outlet voltage of the power generator, the voltage level of the direct-current bus is improved, bus current is reduced under the same power, the wind power converter main circuit topological structure is applicable to a high-power direct-drive type wind power converter, a control mode is flexible, meanwhile, insulating difficulty is reduced, the whole structure is more compact compared with the situation that an IGBT power device or a bus parallel-connection circuit is purely replaced, the occupied area of the converter is reduced, and design and type selection and systematic configuration can be achieved easily.

The invention provides a photovoltaic system maximum power point tracing method. The method comprises the steps that 1, the power value P of a photovoltaic system is obtained in real time; 2, a limit marking value M is obtained according to the current MPPT disturbance period system power value P(k), the set limit power value PLimit and the limit power dead zone PStep; 3, the disturbance direction DFlag is determined according to the current MPPT disturbance period system power value P(k), the previous MPPT disturbance period system power value P(k-1) and the maximum power tracking dead zone PDead; 4, according to the formula: Vmmpt(k)=Vmppt(k-1)+M*DFlag*VStep, the maximum power disturbance voltage Vmppt (k) is obtained for maximum power tracking. By the adoption of the technical scheme, the photovoltaic system maximum power point tracing method has the advantages that full load and limiting output power of a photovoltaic inverter are smooth; the full-load power and limit power of the photovoltaic system are accurate, and the output power is stable; bus voltage is more stable, and a system loop is more reliable.

The invention relates to the technical field of energy management, in particular to an energy management technology aiming at a marine direct current hybrid power system, and particularly relates to an energy management method aiming at the marine direct current hybrid power system composed of multiple groups of fuel cells, multiple groups of lithium batteries and a super capacitor. By monitoring information such as bus voltage and residual electric quantity of each power supply, each power supply DC/DC converter in the marine direct-current hybrid power system is controlled, so that the hybrid power system is switched among 11 working modes, flow of energy in the hybrid power supply is timely allocated, the stability of the direct-current bus is ensured, and the service life of the hybrid power supply is prolonged. The hybrid power supply system rapidly tracks load changes, and stable and reliable operation of the whole DC hybrid power system is realized.

The invention relates to a non-communication bus voltage zero-deviation control method. Bus voltage stability and accurate load current allocation are used as control targets, accurate line impedanceinformation is acquired by an active measurement method and is introduced to a droop coefficient so as to make up influence of line impedance inconsistency on current allocation, and a load current can be accurately allocated during the steady-state and dynamic process. Moreover, virtual bus voltage information is introduced, a bus voltage stably runs at a rated value according to a translation compensation principle, and current allocation is not affected. With the control method proposed by the invention, the defect of traditional droop control is overcome, interconnection communication is not needed, the plug and play requirement is met, the capacity expansion of the system is facilitated, and the system reliability is greatly improved.

The invention discloses a flexible power tracking control method of a photovoltaic power generation unit and application thereof. The photovoltaic power generation unit is connected to the DC bus through the DC-DC converter, and the load is connected to the DC bus. According to the control method, the reference power and the output power of the photovoltaic power generation unit are judged, the working state of the photovoltaic power generation unit is selected as an MPPT mode or a constant power tracking mode, the output of the photovoltaic power generation unit is controlled in real time, and the DC bus voltage is adjusted. The method is suitable for occasions where the illumination intensity and the load power change continuously. When the photovoltaic power generation unit is applied to a traction power supply system and a micro-grid system, the use of a brake resistor and a heat dissipation device can be reduced, the cost is reduced, the capacity of other voltage stabilizing devices such as an energy storage device can be reduced, and the service life of the energy storage device is prolonged.

The invention discloses a three-port direct-current energy router power coordination control method, which comprises the following steps that: a port power controller collects a direct-current bus voltage value of each microgrid, and performs per-unit processing on the active power droop characteristic of the bus voltage value to obtain a voltage per-unit value of each port; therefore, different droop characteristics of the three direct-current micro-grids can be unified, and the direct-current micro-grids can be analyzed and power transmission of each port of the three-port direct-current energy router can be controlled under the same coordinate system. The transmission power deviation of each energy router port is calculated according to the voltage per unit value of each port; and a TABinternal controller converts the transmission power deviation of each energy router port into an adjustment amount of a phase shift angle between the energy router ports. Driving pulses of all switches of the TAB converter are obtained through continuous phase modulation, and power coordination control over the three-port direct-current energy router is achieved. The bus voltage stability can bemaintained, and the risk coping capacity of a power grid system is improved.

The invention relates to a sine wave inverter with switchable output voltages. The sine wave inverter comprises a push-pull boosting main circuit, a full bridge inversion main circuit, a fore-level drive protecting circuit and a back-level drive protecting circuit. A 24-volt storage battery is electrically connected with the push-pull boosting main circuit. The push-pull boosting main circuit is in signal connection with the fore-level drive protecting circuit, the back-level drive protecting circuit and the full bridge inversion main circuit. The full bridge inversion main circuit is in signal connection with the back-level drive protecting circuit. When the 24-volt storage battery is connected to the inverter, two kinds of different amplitudes of alternating voltages can be output, and immediate switching of the two kinds of output voltages can be achieved through a switch. The output alternating voltages are pure sine waves, the harmonic content is small, the interference on the load is small, and the overall conversion efficiency can reach to more than 90 percent.

The invention discloses a magnetically-controlled static var compensator, which mainly solves the defects that in the prior art, the existing reactive compensation is stepped and low in accuracy, and cannot provide inductive reactive power or capacitive reactive power synchronously; the switching operation is frequent; the higher requirements of the electrical power system and users cannot be met. The magnetically-controlled static var compensator comprises a digital signal processor, a power supply, a capacitor bank or a filter bank, a keyboard, a liquid crystal displayer, a programmable logic controller, a reactive compensation unit, CSR (Controllable Shunt Reactors), and an AD (Analog-to-Digital) sampling circuit, wherein the output ends of the power supply, the capacitor bank or the filter bank and the keyboard are all connected with the digital signal processor; the input ends of the liquid crystal displayer, the programmable logic controller and the reactive compensator are all connected with the digital signal processor; the controllable shunt reactors are connected with the reactive compensation unit and the programmable logic controller; the input end of the AD sampling circuit is connected with the controllable shunt reactors, while the output end is connected with the digital signal processor. By virtue of the scheme, the magnetically-controlled static var compensator can reach the target of high cost performance and meet the actual demand, and is of high practical value and promotion value.

A multi-diode series connection type back-to-back bridgeless three-level rectifier comprises two bridge arms, namely a multi-diode rectifier bridge arm and a traditional rectifier bridge arm. Compared with the traditional rectifier bridge arm, the rectifier reduces the voltage stress borne by the MOS transistor through series connection of the multiple diodes. Meanwhile, an additional power branch is provided to be directly connected to the midpoint of the series capacitor. According to the rectifier, an extra power channel is provided, and meanwhile, a new diode structure is added, so that the stability and the reliability of a circuit are improved. Except the power input end back-to-back MOS transistor group, each MOS transistor is provided with an additional diode to share voltage stress, so that the switching loss is relatively small, the circuit heating is reduced, and the circuit efficiency is improved. Compared with a traditional two-level rectifier, the rectifier has the advantages that the number of levels of phase voltage on the alternating current side can be three, and the capacitance value can be remarkably reduced; the voltage stress of the device is reduced; the circuit size and cost are reduced; output voltage ripples are reduced; and the volume and the cost of the capacitor and the semiconductor device are reduced.