14 results about "Dc bus voltage regulation" patented technology

The invention relates to a coordination control method and system for a direct-current energy consumption device and an offshore wind turbine. The method comprises the following steps that operation data of a flexible direct-current system are obtained; the voltage of the direct current bus is monitored in real time, and when it is monitored that the land large power grid breaks down, the surplus power of the flexible direct current system is calculated; if the direct-current bus voltage exceeds a preset voltage threshold value, a direct-current energy consumption device is started, and a power consumption distribution problem is constructed and comprises a target function constructed with minimization of direct-current bus voltage regulation deviation and offshore wind turbine power regulation deviation as a target and constraint conditions constructed based on operation data; the power consumption distribution problem is solved, and the optimal consumption power of the direct-current energy consumption device and the optimal consumption power of the offshore wind turbine are obtained; the target power adjustment amount of each offshore wind turbine is calculated based on the optimal offshore wind turbine consumption power and the corresponding variable pitch response weight; and controlling the flexible direct current system based on the target power adjustment amount and the consumed power of the direct current energy consumption device.

The invention discloses an inter-pack balanced power transmission system and method of a battery pack, and relates to the technical field of battery management, and the method comprises the steps that each slave control module collects data in real time, and uploads the data to a master control module; the main control module distributes a dynamic weight factor for each battery pack according to the health state of each battery pack and the operation efficiency of the corresponding direct-current converter, generates a dynamic optimal bus voltage reference value, and controls the main converter to adjust the common direct-current bus voltage to the reference value; when it is judged that inter-group energy transmission is needed, an energy transmission instruction is issued to a related slave control module; analyzing the expected efficiency of a direct energy transmission path and a relay energy transmission path through a relay battery pack, selecting a path with higher expected efficiency as a final energy transmission scheme, and issuing the final energy transmission scheme to a related slave control module; and the slave control module generates a charging and discharging control instruction according to the energy transmission scheme to complete balanced power transmission.

The invention discloses an automatic coordination network construction type multi-time scale hybrid energy storage system and method, and belongs to the technical field of energy storage and new energy. In the system, a super capacitor is connected in parallel with a direct current bus of an inverter; the inverter adjusts the phase of the AC side output voltage according to the DC bus voltage; the first DC / DC converter regulates and generates an output current instruction of the short-time energy storage battery according to the DC bus voltage, and tracks the output current instruction of the short-time energy storage battery through a current inner loop PI controller; and the second DC / DC converter inputs the filtered DC bus voltage difference into the PI controller with amplitude limiting and saturation resistance to generate an output current instruction of the amplitude-limited long-time energy storage battery, and the output current instruction of the amplitude-limited long-time energy storage battery is tracked through the current inner loop PI controller. According to the invention, automatic coordination distribution output among energy storage systems with different time scales can be realized without depending on communication, and the response speed and reliability of the system are improved.

The invention discloses a buck-boost circuit, a control method, a driving circuit and electric equipment. The buck-boost circuit comprises a sampling module, the first end of which is connected with the positive terminal of a DC bus, the second end of which is grounded, and the third end of which is connected with a control module, and which is used for collecting the voltage of the DC bus; the buck-boost module is arranged on the direct current bus and comprises an excitation loop arranged on the output side of the rectifier module; the power supply loop is arranged on the input side of the inversion module; the power supply loop is connected with the excitation loop; and the control module is used for switching the conduction state of the power supply loop according to a set period, and adjusting the conduction duration of the excitation loop in one period according to the direct current bus voltage so as to control the boost-buck module to boost and buck. According to the invention, the buck-boost of the buck-boost module can be adaptively controlled according to the fluctuation condition of the bus voltage, thereby reducing the fluctuation amplitude of the DC bus voltage.

The invention discloses an energy storage battery direct-current grid-connected system for preventing bus current feedback, relates to a grid-connected power circuit and a grid-connected control circuit, and belongs to the field of direct-current bus voltage regulation and control. The system comprises a control part and a power part, the control part comprises a storage battery voltage isolation sampling unit, a data processing unit, a bus voltage isolation sampling unit and an isolation driving unit; the power part comprises a storage battery unit, a load unit, a power generation unit, an MOS tube unit, an ideal diode unit and a fly-wheel diode unit. Three system states of grid-connected channel closing, trickle charging and grid-connected channel opening are switched by analyzing the magnitude relationship between the storage battery voltage and the bus voltage in real time, the storage battery is prevented from being damaged by impact current, the long-term floating charging performance is prevented from being reduced, meanwhile, the bus energy is fully utilized, and the system reliability is improved. The method is especially suitable for a system which takes generator power supply as a main power supply and storage battery emergency power supply as an auxiliary power supply and has inductive load on a bus.

The application provides a kind of virtual DC motor model-free self-learning control method of port commercial ship micro-grid, to improve the stability of ship micro-grid DC bus voltage under the access of port commercial ship shore power, comprising the following steps: collecting ship micro-grid DC bus voltage, establishing ship virtual DC motor model and discretizing armature equation;Establish a tight format local linearization data model related to virtual DC motor input moment of inertia and output DC bus voltage;Design moment of inertia model-free self-learning controller and calculate pseudo partial derivative according to input and output data;Design adaptive adjustment of moment of inertia;By controlling ship micro-grid Buck / Boost converter, simulate the external characteristic of DC generator to stabilize DC bus voltage.The application effectively suppresses the fluctuation of ship micro-grid DC bus voltage caused by load switching and new energy output change under the access of port commercial ship shore power, while also optimizes the dynamic response speed of ship micro-grid DC bus voltage regulation.

The invention relates to the technical field of flexible direct current transmission frequency support control, in particular to a virtual inertia cooperative control method, system, equipment and medium for a back-to-back modular multilevel converter, and the method comprises the steps: dividing a positive frequency deviation scene and a negative frequency deviation scene; when a receiving end system is in a positive frequency deviation scene, sending end active power virtual inertia control is enabled, and receiving end direct current bus voltage virtual inertia control is closed, so that the direct current overvoltage risk is avoided; when a receiving end system is in a negative frequency deviation area, sending end active power virtual inertia control is combined with receiving end voltage virtual inertia control, inertia support is realized, and the voltage stress of each semiconductor power device is effectively reduced; the impedance of the direct current transmission line is considered under the active power virtual inertia control method, and a sending end power instruction value is corrected; the relationship between the AC voltage of the sending and receiving ends and the DC bus voltage is considered under the DC bus voltage virtual inertia control method, and it is ensured that overmodulation does not occur in the DC bus voltage regulation range of the MMC of the sending and receiving ends.

The invention discloses an industrial and low frequency weak coupling half-wave shaping multi-level AC converter topology, which belongs to the technical field of AC-AC conversion, and comprises an I-type converter and an II-type converter which are respectively arranged on a low frequency side and a power frequency side, the I-type converter and the II-type converter adopt heterogeneous half-wave shaping multi-level converters, and the I-type converter and the II-type converter are connected with the I-type converter and the II-type converter. The I-type current converter and the II-type current converter are respectively composed of three phases of independent phase units, and each phase of the I-type current converter is composed of a multi-level shaping unit I and a half-wave reversing unit I which are connected in parallel; and each phase of the II-type converter is formed by connecting a multi-level shaping unit II and a half-wave commutation unit II in an embedded manner. The half-wave shaping multi-level AC converter topology with low frequency weak coupling is adopted, the core lies in weakening the strong constraint of a traditional AC-DC-AC complete decoupling topology on a DC link, the DC link is allowed to have coupling of harmonic components on the two sides, and the DC bus voltage has flexible adjustment capability.

The application discloses an LED driving circuit and a dimming control method thereof. The driving circuit is connected with a dimmer to obtain a chopped AC input voltage and is connected with an LED to control a load current flowing through the LED. The driving circuit comprises a current control circuit for controlling the load current flowing through the LED and adjusting a duration of the load current in a half power frequency cycle according to a DC bus voltage to realize dimming. The current control circuit obtains a conduction angle range of the dimmer according to a detected value of the load current, selectively operates in one of an open loop mode and a closed loop mode, maintains the load current as a reference current in the open loop mode, and adjusts the load current according to a negative feedback of the DC bus voltage in the closed loop mode. The LED driving circuit controls a conduction state of a transistor in different modes according to different conduction angles of a thyristor in the dimmer, and can balance brightness stability and adjustment response speed of dimming.

This invention discloses a wide-range radio frequency power conversion system based on an asymmetric hybrid structure and hybrid modulation. It adopts an input parallel, output series architecture, consisting of a main power regulation module and several auxiliary power modules. The main power regulation module includes a front-stage Buck-Boost converter and a rear-stage dual-parallel full-bridge resonant unit, possessing fine voltage and phase adjustment capabilities. The auxiliary power modules are simplified full-bridge units, responsible only for discrete power switching. The system employs a hybrid modulation strategy, utilizing phase-shift control of the main power module in the low-power range, DC bus voltage regulation of the main power module in the medium-power range, and full-bridge / bypass mode switching of the auxiliary power modules in the high-power range, achieving smooth and continuous adjustment from zero to rated power. This architecture, through optimized design of resonant network parameters and utilization of the internal resonant circulating current generated by the main module in phase-shift state, ensures zero-voltage switching (ZVS) operation across the entire range, significantly reducing system hardware costs and control complexity while significantly improving system efficiency in power back-off state.

Systems and methods relating to control systems for DC / AC inverters that receive power from photovoltaic based renewable energy resources. When the DC / AC inverters are operated in on-grid mode, the DC / AC inverters and the DC / DC control system operate to provide on-grid functions such as maximum power point tracking (MPPT) and DC-bus voltage regulation. When in off-grid mode, the DC / AC inverter and the off-grid control system regulates the resulting AC voltage from the DC / AC inverter to be within a pre-set range. The off-grid control system is based on differential geometry and uses a Lie Group controller for setting a frequency reference signal. The frequency and current amplitude reference are used to generate a sinusoidal current reference signal which is then tracked by a current controller. The current controller controls the switches in the DC / AC inverter to regulate the AC voltage.

The application discloses a kind of inter-battery equalization power transmission system and method of battery pack, it is related to battery management technical field, the method includes: each slave control module real-time data acquisition, and upload to main control module;Main control module each battery pack health state and corresponding dc converter operating efficiency, for each battery pack allocation dynamic weight factor, generate dynamic optimal bus voltage reference value, and control main converter will public dc bus voltage be adjusted to reference value;When determining that inter-battery energy transmission is needed, energy transmission instruction is issued to relevant slave control module;The expected performance of direct energy transmission path and through relay battery pack is analyzed to carry out relay energy transmission path, the path with higher expected performance is selected as the final energy transmission scheme, and is issued to relevant slave control module;Slave control module generates charge-discharge control instruction according to energy transmission scheme, and completes equalization power transmission.

This application relates to a communication-free dynamic voltage droop control method and system for DC microgrids. The DC microgrid includes multiple distributed generation units, each equipped with a power electronic converter and a local controller. The method collects local voltage, current, and DC bus voltage measurements from each distributed generation unit, inputs the measurement data into the artificial intelligence control module in the local controller, and generates adaptive voltage droop control parameters in real time based on a pre-trained deep reinforcement learning model. These parameters are then applied to the voltage reference value generation stage of the power electronic converter. Through dual closed-loop control of voltage and current, DC bus voltage regulation and power sharing among distributed generation units are achieved. Each distributed generation unit operates independently, and there is no communication between units during the control process. This application eliminates the need for a secondary control layer, achieving decentralized and stable operation under load fluctuations and power supply changes.

The invention provides a port micro-grid direct current bus voltage intelligent control method based on a virtual direct current motor, and relates to the technical field of port micro-grid control. The method comprises the following steps: firstly, collecting port microgrid DC bus voltage, and establishing and discretizing a virtual DC motor model; then, a tight-format dynamic linearization data model between the virtual mechanical torque and the direct-current bus voltage is constructed; a pseudo partial derivative is calculated based on input and output data, a model-free adaptive controller is designed, and adaptive compensation of the virtual mechanical torque is realized; performing adaptive adjustment on parameters of the model-free adaptive controller by utilizing reinforcement learning; and finally, simulating external characteristics of the direct-current motor by controlling the power converter to realize stable control of the direct-current bus voltage. According to the method, the DC bus voltage fluctuation caused by loading and unloading equipment start and stop, load switching and new energy output fluctuation in the port microgrid can be effectively suppressed, and the dynamic response performance of DC bus voltage regulation and the system operation stability are improved.