187 results about "Phase converter" patented technology

The invention relates to the technical field of power systems, in particular to a comprehensive power quality regulation and control system and method for a low-voltage transformer area, the system comprises an information processing control platform, an information acquisition terminal and power regulation and control equipment, and the power regulation and control equipment comprises four information acquisition terminals, a phase converter and a reactive power compensation device. Data such as operation state and working state are collected, and the power quality abnormity reason is accurately positioned. Through issuing an area control strategy or a transformer area self-operation control strategy, when the power quality of a power grid is abnormal, voltage regulation, three-phase imbalance regulation and photovoltaic absorption are respectively carried out through power regulation and control equipment, and comprehensive treatment of the power quality is realized.

The invention discloses a weight coefficient-free model prediction control system and method for a permanent magnet synchronous motor, and particularly belongs to the field of permanent magnet synchronous motor control. The control system comprises a direct current voltage source, a three-phase converter, a permanent magnet synchronous motor, a rotating speed outer ring PI control module, an MTPA flux linkage calculation module and a model prediction control module. The control method comprises the following implementation steps: firstly, establishing a torque and flux linkage prediction model of the permanent magnet synchronous motor; then, a reference torque amplitude value and a reference flux linkage amplitude value are obtained through a rotating speed outer ring PI controller and a maximum torque per ampere (MTPA) calculation module respectively; secondly, constructing an independent torque cost function and a flux linkage cost function according to the torque error and the flux linkage error, and forming a cascade form; evaluating the switching states by using a cost function, selecting two vectors from the eight switching states of the converter by using the independent cost function of the torque (or flux linkage), and selecting an optimal vector from the two vectors by using the independent cost function of the flux linkage (or torque); and finally, the execution sequence of the torque and flux linkage cost function is alternated in each subsequent period. Compared with the prior art, the method avoids complex weight coefficient design through a cost function cascading mode, alternates the execution sequence of the cost functions in each period, dynamically balances the weights of the two control targets, and reduces the number of calculation times.

The invention discloses a control method, a control device and a switching power supply, the control method is applied to a three-phase converter, and the control method comprises the following steps in a time interval: a sampling signal acquisition step: acquiring a first sampling signal representing the state of each phase, the state can represent the size relation of the maximum average switching current absolute value of each phase of bridge arm; in the working mode selection step, the working mode of the corresponding phase bridge arm is selected according to the first sampling signal of each phase, and when the maximum average switching current absolute value represented by the first sampling signal is maximum, the corresponding phase bridge arm works in a clamping mode; when the maximum average switching current absolute value represented by the first sampling signal is centered, the corresponding phase bridge arm works in a CRM mode; and when the maximum average switching current absolute value represented by the first sampling signal is minimum, the corresponding phase bridge arm works in a TCM mode. According to the invention, soft switching conditions can be provided for the three bridge arms of the three-phase converter.

A circuit for slew rate detection and phase control in a multi-phase converter is provided. The circuit includes a first comparator configured to trigger when an output voltage of the multi-phase converter falls to a first output voltage level threshold value. The circuit further includes a second comparator configured to trigger when the output voltage falls to a second output voltage level threshold value which is lower than the first output voltage level threshold value. The circuit further includes a timer configured to start to run for a predefined time window, when the output voltage of the multi-phase converter falls below first output voltage level threshold value. The circuit further includes phase control logic configured to distinguish the ramp rate of the output voltage of the multi-phase converter as corresponding to a slow-rate ramp, a mid-rate ramp or a fast-rate ramp based on the outputs of the first comparator, the second comparator and the timer and enable phases synchronously or asynchronously based on the distinguishing of the ramp rate of the output voltage of the multi-phase converter as corresponding to the mid-rate ramp or the fast-rate ramp.

The invention discloses a power oscillation suppression method and a power oscillation suppression system for a multi-construction-network type converter parallel system, which relate to the technical field of converter control and comprise the following steps of: acquiring voltage, current and voltage frequency output by a three-phase converter at a grid-connected point in the multi-construction-network type converter parallel system; calculating active power and reactive power and inputting the active power and the reactive power into the virtual oscillator; according to the voltage frequency and the rated frequency, system power reference compensation is obtained through an introduced proportional differential controller, then the active power and an active power reference value are combined, frequency deviation is obtained through an active droop link of a virtual oscillator, and then a voltage phase angle is obtained through calculation; meanwhile, the reactive power is subjected to a reactive power control link of the virtual oscillator to obtain a voltage amplitude; and calculating a system reference voltage according to the voltage amplitude and the voltage phase angle, and performing real-time adjustment on the output of the three-phase converter through voltage and current double-closed-loop adjustment and PWM (Pulse Width Modulation) control so as to suppress the frequency oscillation of the system.

The present invention discloses a multi-phase converter circuit, which includes at least one two-phase converter circuit coupled between a first voltage and a second voltage, and employs switching control of at least one capacitor and at least one coupled inductor, with alternated charging phase and discharging phase, to achieve power conversion between the first voltage and the second voltage.

The invention provides a prediction control method and system for two parallel three-phase converters based on ring current symmetry, and the method comprises the steps: firstly, screening out an optimal vector combination beneficial to ring current suppression, enabling the vector combination to overturn the polarity of the ring current change rate in a single period, and facilitating the optimization of the peak value and the average value of the ring current; on the basis, a brand-new model prediction control set is established; then, on the basis of the provided optimal control set, the circulating current average value is incorporated into a cost function of model prediction control, the provided cost function selects an optimal vector combination in real time by evaluating circulating current average value tracking errors of all combinations in two control periods, suppression of low-frequency circulating current and elimination of direct-current components are achieved, and meanwhile, the low-frequency circulating current and the direct-current components are controlled in real time. Due to the fact that the optimal vector combination achieves loop-to-polarity single-period flipping, the method can further push the loop frequency spectrum up to a high-frequency area. According to the invention, suppression of the low-frequency circulating current is realized, and the direct-current component of the circulating current is completely eliminated.

The invention relates to a compact railway energy regulation and control complex which comprises a converter unit with an intermediate frequency transformer as a core, and an alternating current port of each converter unit is connected with buses of alpha and beta phase traction feeder lines on the secondary side of a V / v traction transformer in series. A magnetic field hedging decoupling inductor and a filter capacitor of the medium-frequency transformer form a secondary harmonic filter branch on the direct current side of each converter unit, non-negligible secondary harmonic components on the direct current side of each converter unit in the single-phase converter system are filtered out, and a power winding of the medium-frequency transformer is connected with a DC / DC converter on the inner side of each converter unit. The compact railway energy regulation and control complex can accurately control the tidal current distribution of the two power supply arms, carries out comprehensive energy regulation and control through a direct current port and an external energy storage and new energy power generation system, can effectively inhibit the voltage fluctuation of a feeder line side, improves the comprehensive energy utilization rate and the new energy consumption rate of an electric railway system, and improves the energy utilization rate of the electric railway system. Compensating the power factor of the high-voltage side of the transformer substation and inhibiting the voltage unbalance degree of the PCC point.

The disclosure concerns a control method for operating a multi-phase converter with a number N of phases, N being at least three, said converter including a transformer, a primary side circuit which includes primary switch legs with primary switches connected to a primary side of the transformer, and a secondary side circuit which includes secondary switch legs each with at least one secondary switch connected to a secondary side of the transformer, the method including: a boost operation mode including a shorting step of shorting the secondary side circuit by controlling a plurality of secondary switches of separate secondary switch legs to be simultaneously ON, said shorting step is repeated periodically within one switching time period T; and / or a phase-modification operation mode including a phase-reduction step of reducing an operating phase of said converter by controlling all primary switches of at least one primary switch leg to be simultaneously OFF.

The invention discloses a control method, a control device and a switching power supply, the control method is applied to an N-phase converter, and the control method comprises the following steps: calculating an electrical parameter output by the N-phase converter and a modulation wave required by each phase bridge arm switching tube when a common-mode voltage reaches an expected value through voltage loop and current loop double closed-loop control; adjusting the current modulation wave of each phase of bridge arm switch tube so as to obtain N first modulation waves; calculating a second frequency required by a modulation wave of each phase of bridge arm switch tube when each phase of bridge arm switch tube realizes ZVS by predicting the magnitude of bridge arm side inductive current pulsation in each phase of LCL filter, taking the second frequency as the frequency of a carrier wave, and generating N carrier waves; and comparing the first modulation wave of each phase of bridge arm switch tube with the corresponding carrier wave to obtain a driving signal for controlling the on and off of each phase of bridge arm switch tube. According to the invention, good harmonic performance can be obtained while low common-mode voltage is realized.

An example apparatus to control a power stage circuit includes: programmable circuitry configured to: generate, in response to an instruction from an external controller, a pulse in a first local clock signal, the pulse in the first local clock signal generated when a fly capacitor in the power stage circuit has discharged for a discharge period that is less than a threshold amount of time; and generate a pulse in a second local clock signal after the fly capacitor has charged for a charge period, wherein a length of the charge period is based on the length of the discharge period.

An optical module includes: an optical modulation chip having an optical modulator, the optical modulator including a phase converter, a first optical power detection assembly and a second optical power detection assembly arranged at light input and light output sides of the optical modulator, a comparison circuit configured to receive a second detection voltage and a first detection voltage from the second and first optical power detection assemblies and output a comparison voltage; and an MCU configured to monitor the comparison voltage and output a bias voltage to the phase converter, adjust the bias voltage to the phase converter in case of monitoring the comparison voltage not equal to a preset voltage while the optical module is in a preset state, such that a difference between the first detection voltage and the second detection voltage is a preset difference, thereby adjusting the comparison voltage to a preset voltage.

The present invention belongs to the technical field of power electronic converters and discloses a medium-voltage distribution network flexible interconnection switch topology and control method. The medium-voltage distribution network flexible interconnection switch topology provided by the present invention includes three connected reactors L1, three connected reactors L3, two chain-type STATCOMs, two three-phase isolation transformers, two three-phase LC filters, two three-phase inverter circuits, and a DC port. Back-to-back three-phase converters are introduced at the ends of the chain-type STATCOMs of two feeders. Through the back-to-back three-phase converters, active power flow mutualization between the two medium-voltage chain-type STATCOMs, that is, between two different feeders, can be achieved. The present invention can achieve DC capacitor voltage balancing of the chain-type STATCOM submodules of the two feeders. Compared with the BTB-VSC commonly used in existing medium-voltage distribution network flexible interconnection demonstration projects, this solution has lower cost, simpler topology, easier control, and does not need to consider the active and reactive power decoupling issues between interconnected feeders, making it easy to promote and apply on a large scale.

Disclosed are a clock phase converter and a phase converting method that can generate a converted clock signal with a desired amount of delay by selecting and outputting an output signal corresponding to a preset value among output signals of a plurality of delayed clock signal generators that detect the transition of a clock signal and generate delayed clock signals by sequentially delaying the clock signal by a certain period of time.

The invention discloses an on-load control method for a split-phase converter with single-phase bypass input, and the method comprises the steps: carrying out the adjustment of the AC output voltage of a first inversion module based on the commercial power voltage, the actual DC bus voltage, and the first AC output voltage and first AC output current of the first inversion module in the split-phase converter, the first alternating-current output voltage of the first inversion module is kept at the split-phase voltage; and based on the commercial power phase angle, the actual DC bus voltage, and a second AC output voltage and a second AC output current of a second inversion module in the split-phase converter, the AC output current of the second inversion module is adjusted, so that the power of the second split-phase load is balanced with the power of the first split-phase load. The split-phase voltage is constructed under the condition that the single-phase mains supply is input into the split-phase converter, and the split-phase two-phase voltage balance can be maintained even under the working condition of unbalanced split-phase load.

A grid forming converter (32), is arranged to provide a single-phase or multi-phase converter current. Its control comprises: - a grid forming controller (33) determining (101) a voltage reference value (formula (I)); - a voltage controller (34) determining (102) a current reference value î; - a current limiter (35) determining (103), from the current reference value î, a limited current reference value (formula (II)); - a current controller (36) controlling (104) the converter (32) to provide the converter current i prescribed by the limited current reference value (formula (II)). Therein, at least while a fault condition is present, the voltage controller (34) generates a current reference î based on a relationship between a representative (formula (III)) of a virtual internal voltage (formula (IV)) and a representative (formula (III)) of an actual voltage value ν, the phase angle of the virtual internal voltage (formula (IV)) is controlled to match with the phase angle reference of the voltage reference (formula (I)) and the magnitude of the virtual internal voltage (formula (IV)) is adaptively changed depending on overcurrent conditions.

A grid forming converter (32), is arranged to provide a single-phase or multi-phase converter current. Its control comprises: • a grid forming controller (33) determining (101) a voltage reference value v̂; • a voltage controller (34) determining (102) a current reference value î; • a current limiter (35) determining (103), from the current reference value î, a limited current reference value ; • a current controller (36) controlling (104) the converter (32) to provide the converter current i prescribed by the limited current reference value . Therein, at least while a fault condition is present, the voltage controller (34) generates a current reference î based on a relationship between a representative v̂rep of a virtual internal voltage v̂vir and a representative vrep of an actual voltage value v, the phase angle of the virtual internal voltage v̂vir is controlled to match with the phase angle reference of the voltage reference v̂ and the magnitude of the virtual internal voltage v̂vir is adaptively changed depending on overcurrent conditions.

The present invention relates to the technical field of direct current transmission systems, and discloses a commutation control method, device, electronic device and readable storage medium of a converter. The method comprises: obtaining the commutation state of the converter; judging whether the commutation state is normal; when the commutation state is abnormal, controlling the converter to start the energy consumption mode and adjusting the energy consumption parameters of the converter. By implementing the present invention, on the basis of ensuring the successful commutation from the main branch to the auxiliary branch, the transmission power in the direct current transmission system where the converter is located can be maintained by adjusting the energy consumption parameters of the converter, avoiding the influence of the receiving end AC fault on the direct current transmission system, and ensuring that the direct current transmission system is in a stable operating state.

The utility model relates to a three-power three-phase efficient elevator energy recovery multi-level converter, which comprises a first direct-current voltage source, a second direct-current voltage source, a third direct-current voltage source, a first direct-current bus capacitor, a second direct-current bus capacitor and a third direct-current bus capacitor, the first DC voltage source is connected in parallel with a first DC bus capacitor, the second DC voltage source is connected in parallel with a second DC bus capacitor, the third DC voltage source is connected in parallel with a third DC bus capacitor, the anode end of the first DC voltage source is connected with the DC bus anode P end, and the cathode end of the third DC voltage source is connected with the DC bus cathode N end; the direct-current bus positive pole P end and the direct-current bus negative pole N end are connected with the input ends of the A-phase converter, the B-phase converter and the C-phase converter respectively, and the output ends of the A-phase converter, the B-phase converter and the C-phase converter are connected with the traction motor. The efficiency of the elevator energy recovery converter can be effectively improved, and consumption reduction and energy conservation are achieved.

The invention discloses an on-load voltage regulation distribution transformer with series converter chains bearing partial power, which is characterized by comprising a group of three-phase series converter chains and a three-phase industrial frequency transformer, the three-phase series converter chain is used for three-phase voltage regulation and comprises three converter sub-chains and N4 three-phase converter sink chains, and N4 is equal to 0 or 1; the three-phase industrial frequency transformer is used for isolating and reducing voltage and providing an energy transfer port for maintaining energy conservation of the three-phase series converter chain, the three-phase industrial frequency transformer comprises 3N0 + 3N1 + 3N2 + 3N2 + 3N4 primary windings and three secondary windings, and N0 is greater than or equal to 0; the invention solves the problems of short service life of the contact and power supply interruption of the sensitive load, and realizes continuous voltage regulation with lower equipment cost.

The invention relates to the technical field of rural power distribution networks, and provides an agricultural power distribution network three-phase imbalance energy storage and power mutual aid allocation system, which comprises a monitoring unit, a power distribution unit, a power distribution unit and a power distribution unit, a decision unit: when delta Ugt; when 5%, triggering adjustment, and identifying the highest voltage phase, the lowest voltage phase and the intermediate voltage phase; the execution unit comprises a power mutual aid module and an energy storage adjusting module; and the power mutual aid module is used for transferring the excess power of the phase with the highest voltage to the phase with the lowest voltage through the three-phase converter. The three-phase voltage deviation ratio is reduced to be within 3%, the intermediate phase voltage is stabilized to be + / -2%, and THDlt is achieved through harmonic suppression; and the voltage of the direct-current bus is stabilized at 750-800V, so that the power supply quality and economical efficiency of the agricultural distribution network are improved.

The utility model relates to a load converter device for quickly switching alternating current, which comprises alternating current load equipment, the alternating current load equipment comprises a load equipment shell, and a converter main body is arranged in the load equipment shell; a converter main body is arranged in the load equipment shell; the converter main body is divided into a three-phase converter main body and a single-phase converter main body; during installation or use, if a three-phase load needs to be used, the three-phase converter main body is connected; when a single-phase load is needed, the single-phase converter main body is connected, plugging operation is carried out at the wiring terminal, operation can be carried out without using any tools such as a screwdriver, and the purpose of rapid, safe and convenient switching can be achieved. Compared with the prior art, the load converter device provided by the utility model not only can improve the test work efficiency and reduce the test cost, but also can avoid the hidden danger phenomenon of unsafe risk caused by separate wiring or repeated wiring operation.

The present invention provides a control method and device for a three-phase converter port impedance measurement device, including measuring the electrical parameters of the port impedance measurement device; taking the electrical parameters of the port impedance measurement device as input quantities, inputting them into a preset pre-measurement model and a preset command quantity model, and respectively determining the pre-measurement and command quantity of the port impedance measurement device according to the change in the disturbance voltage frequency output by the port impedance measurement device; determining a design index function according to the pre-measurement and command quantity of the port impedance measurement device; using a model predictive control strategy to determine the switching state of the port impedance measurement device in the next switching cycle according to the design index function, so as to realize the control of the port impedance measurement device. The present invention performs segmented control for command signals of different frequencies, realizes precise voltage output in a wide frequency domain, enables the control signal to cancel the influence of the main circuit of the device under test, and realizes the control of the port impedance wide-frequency measurement device.

The application discloses a control method of a power distribution line ice melting device, which adopts the power distribution line ice melting device to melt ice, and the ice melting device comprises a parallel side converter, a series side converter, an energy storage capacitor, a parallel side transformer and a series side transformer, the energy storage capacitor is connected between the parallel side converter and the series side converter, the parallel side converter is a three-phase converter, absorbs active power of a fundamental frequency from the power distribution network through the parallel side transformer, the series side converter is a single-phase converter, generates non-fundamental wave current, and injects the non-fundamental wave current into a first end of a line to be melted through a neutral point of the series side transformer to generate Joule heat in the line to be melted to melt ice without power-off operation. Compared with the traditional method, the application can effectively reduce the interference on the power grid, reduce the ice melting cost, and improve the stability and reliability of the system.

The application provides a multifunctional static synchronous compensator system, comprising: a plurality of three-phase converter valves, input ends of each three-phase converter valve being connected to a common DC bus; an energy storage valve, being connected in parallel with the three-phase converter valve, and the plurality of three-phase converter valves sharing the energy storage valve through the common DC bus; a switch breaker device, being arranged between the three-phase converter valve and the energy storage valve; and a control unit, being connected with the plurality of three-phase converter valves, the energy storage valve and the switch breaker device respectively. The application also provides a method for operating the multifunctional static synchronous compensator system. The multifunctional static synchronous compensator system provided by the application adopts back-to-back converter valves, shares energy storage elements through a common DC bus, and connects two AC buses to the two sides of the converter valve, so that the system can support the two AC power grids, greatly save the installation capacity of the energy storage elements in the energy storage valve, and provide power interconnection between the two AC power grids and play a role in tidal flow control.

The invention provides a power module control method based on a three-phase SEPIC isolation topology, and the method comprises the steps: calculating an output voltage modulation value according to an output voltage sampling value, an output voltage target value and an output current sampling value of a power module; according to the output voltage modulation value, the duty ratio or the switching frequency of a switching tube of each single-phase converter unit in the power module is calculated; and generating a PWM driving signal for the switching tube of each single-phase converter unit in combination with SPWM modulation according to the duty ratio or the switching frequency. According to the control method of the power module based on the three-phase SEPIC isolation topology, output voltage is used as an outer loop, output current is used as an inner loop, the duty ratio or frequency of a switching tube in the power module is calculated through obtained loop output, and then the power module is controlled in an SPWM mode; therefore, input current is not needed, control is simple, and cost can be reduced.

The optical module provided by the invention comprises a circuit board, a light source and an optical modulation chip, the optical modulation chip is electrically connected with the circuit board, the optical modulation chip comprises an optical modulator, and the optical modulator is configured to modulate direct-current light without carrying data into an optical signal; the light modulator comprises two interference arms; the optical power detection assembly is at least arranged on the light emitting sides of the two interference arms and obtains detection voltage; the MCU is electrically connected with the circuit board, and the MCU is configured to adjust the detection voltage to a preset voltage. The optical power of the optical modulator is adjusted through the heater or the phase converter, and the power consumption of the optical module is reduced.

The invention provides an assembly type comprehensive pipe rack phase change heat storage and heat dispatching integrated system and method, and the system comprises a connector pipe rack which is internally provided with a load side inlet pipe, a load side outlet pipe, a phase change box outlet pipe and a phase change box inlet pipe; the heat exchange pipe gallery is arranged on one side of the connector pipe gallery; a heat exchange unit is arranged in the heat exchange pipe gallery; each heat exchange unit comprises a power assembly, a flow divider, a phase change device, an upper-layer longitudinal heat exchange pipe and a lower-layer longitudinal heat exchange pipe. The energy storage pipe gallery is arranged on the side, away from the connector pipe gallery, of the heat exchange pipe gallery. Heat exchange pipelines and phase change boxes are arranged in components of the assembly type comprehensive pipe gallery in advance, and pipe gallery modules such as a connector pipe gallery, a heat exchange pipe gallery and an energy storage pipe gallery which can be flexibly arranged are formed. According to the module, the arrangement position of the connector pipe gallery can be flexibly adjusted according to the position of a load building above, so that the distance from the load building to a pipe gallery leading-out heat exchange pipe is minimized, heat loss of a heat energy conveying path is reduced, and the overall utilization efficiency is improved.

The invention provides an online monitoring method and device for a direct-current bus capacitor of a three-phase converter, and belongs to the field of bus capacitor monitoring. The method comprises the following steps: determining a first zero-crossing moment of an instantaneous current flowing through a lower capacitor in a direct-current bus capacitor and a second zero-crossing moment after the first zero-crossing moment; the accumulated charge quantity of the instantaneous current from the first zero crossing point moment to the second zero crossing point moment is taken; calculating a voltage difference value according to the first capacitor midpoint voltage corresponding to the first zero crossing point moment and the second capacitor midpoint voltage corresponding to the second zero crossing point moment; and obtaining an estimated capacitance value of the direct-current bus capacitor of the three-phase converter according to the accumulated charge quantity and the voltage difference value. According to the method, the estimated capacitance value of the direct-current bus capacitor of the three-phase converter can be simply and reliably obtained, and the feasibility is high.

To provide a multi-phase converter having an EMC filter that is affected by external magnetic flux, and reduces influence of leakage magnetic flux of a reactor on the EMC filter.SOLUTION: A multiphase converter includes at least five voltage converter circuits connected in parallel, each having a reactor, and an EMC filter connected to the plurality of voltage converter circuits. When a required output is equal to or less than the total maximum output of the two voltage converter circuits, the multi-phase converter stops the voltage converter circuit including the reactor disposed closest to the EMC filter, and sequentially operates a plurality of sets of the remaining voltage converter circuits with a pair of the voltage converter circuits in which the reactors are adjacent to each other as one set.SELECTED DRAWING: Figure 2