108 results about "Phase converter" patented technology

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 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 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.

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.

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 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 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 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.

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

The present invention relates to a DC bus hierarchical response coordinated control method for a hybrid power generation system of supercapacitor energy storage and micro gas turbine, comprising: a micro gas turbine, a generator, a three-phase bidirectional converter, a bus capacitor, an inverter, a load, a DC converter, a supercapacitor, a three-phase converter controller and a DC converter controller. The high-power dynamic response of the supercapacitor energy storage unit compensates for the low dynamic response of the micro gas turbine output power, so that the system is in a state of instantaneous power balance in real time, ensuring the stability of the DC bus voltage and enhancing the adaptability of the micro gas turbine power generation system to pulse power loads. It can ensure the stable operation of the hybrid power generation system of supercapacitor energy storage and micro gas turbine, and improve the transient power quality of the system under impact loads. The proposed method can effectively improve the adaptability of the micro gas turbine power generation system under complex working conditions, and has great promotion and application value.

The invention discloses a multi-phase clock analog domain self-calibration circuit which comprises two phase converter groups, a phase detector, an operational amplifier, two low-pass filters and four buffers. According to the invention, negative feedback is realized by constructing the phase self-calibration loop, the phase deviation of the multi-phase clock is calibrated, different disturbance conditions can be adaptively responded, and real-time phase deviation compensation is realized, so that the robustness and stability of the system are remarkably improved. Besides, the calibration of the phase deviation is realized in the analog domain, the influence of the phase deviation on the performance of the time domain interleaving system can be effectively eliminated, and the ADC output code does not need to be processed by a digital module, so that the design complexity and the power consumption overhead of the system are reduced. Compared with a current mainstream calibration method based on an adjustable delay chain, the calibration method provided by the invention has the advantages that a delay capacitor array is omitted, and the chip area is remarkably saved and the power consumption is further reduced while the calibration precision is kept.

The invention discloses an alternating current and direct current voltage coordination matching control method of a modular commutation type converter. The method comprises the following steps: generating three-phase sine reference signals corresponding to single-phase converters based on electrical data of an MCC alternating current side; on the basis of a delay commutation trigger mechanism, a commutation delay angle is introduced to modulate a three-phase sine reference signal, so that each cascade module chain is controlled to perform voltage synthesis, and a direct-current side output voltage of the modular commutation type converter is obtained; real-time current data of the MCC direct current side are collected, and when it is judged that the direct current side output voltage or the real-time current data meet the voltage reduction triggering preset condition, a commutation delay angle in a delay commutation triggering mechanism is dynamically adjusted according to the direct current side output voltage and the real-time current data; and a target delay angle is obtained to repeat the modulation process of the three-phase sine reference signal until the voltage reduction trigger preset condition is not satisfied any more, so that continuous and stable operation of the AC side voltage during the abnormal drop period of the DC side voltage is ensured.

A control system for multi-phase control of a high-voltage converter includes: a multi-phase converter including inputs and outputs each connected in parallel to convert a direct current (DC) input voltage into a DC output voltage of a different level, and having different phases; and a microcontroller outputting a control signal, which is a PWM signal, to boost or lower the DC input voltage of the multi-phase converter to the DC output voltage of a different level, wherein the microcontroller includes at least one core, and the core includes: a first controller controlling two phases of the multi-phase converter having a phase difference of 180 degrees; and a second controller controlling two different phases of the multi-phase converter having a phase difference of 180 degrees and having a predetermined phase difference from the two phases of the first controller.

The utility model belongs to the technical field of motor forward and reverse phase converters, particularly relates to a motor forward and reverse phase converter with a long service life, and aims to solve the problems that working procedures such as plug dismounting are needed when a motor rotates reversely to adjust phase lines for commutation, labor and time are wasted, the service life is shortened or potential safety hazards are generated in the prior art. Comprising a lower end sleeve and an upper top cover, internal wiring pieces are arranged in the lower end sleeve and the upper top cover, and each internal wiring piece comprises a bottom support, a sleeve, a top plate, a binding post and a spring. According to the utility model, when the upper top cover rotates, the internal contact points are connected with different contact points along with the rotation, the state change causes the change of the circuit connection mode so as to realize the interchange of phase lines, and as the phase change is realized through the rotation, the rewiring or the replacement of a socket is not needed, the conversion of the positive and negative rotation of the motor is realized; the purpose of rapidly adjusting forward and reverse rotation of the motor is achieved, the working efficiency is improved, and time is saved.

This application relates to the field of electromagnetic propulsion technology, specifically disclosing a double-sided long stator linear drive system, including multiple subsystems and a main controller. Each subsystem includes an equal number of linear motor stator segments, six-phase switches, position detection devices, a common AC bus for the subsystem, and a subsystem control bus. The linear motor stator segments are connected to the common AC bus of the subsystem through corresponding six-phase switches, and then connected to the system common AC bus formed by the subsystem bus interfaces, which is connected to a six-phase converter composed of three-phase converters distributed in each subsystem. Each position detection device is connected to the system control bus through the subsystem control bus, and then to the main controller. The main controller controls the switching of each linear motor stator segment according to the installation order of the subsystems and the running position of the linear motor mover measured by the position detection devices. The subsystems can be randomly ordered and assembled without affecting the system operation, exhibiting good mobility.

The invention discloses a flexible alternating-current interconnection device simulation method and system, and the method comprises the steps: constructing a flexible alternating-current interconnection device, and enabling a parallel-side three-phase converter in the flexible alternating-current interconnection device to be connected with a power grid side; based on the first voltage output by the power grid side, performing phase-locked loop simulation, dq conversion and anti-dq conversion simulation on a parallel side three-phase converter in the flexible AC interconnection device to obtain a first trigger signal; based on the first trigger signal, performing control simulation on a parallel side single-phase converter in the flexible AC interconnection device to obtain a second trigger signal; and based on the second trigger signal, performing phase-locked loop, control loop and inverse dq conversion simulation on the series-side single-phase converter in the flexible AC interconnection device to obtain a final trigger signal, so that the series-side single-phase converter performs power flow regulation and control, and the method can accurately reflect the actual operation state of the flexible AC interconnection device.

The utility model relates to the technical field of power equipment, in particular to a single-phase converter transformer which comprises a transformer body and a temperature control oil tank, a hot oil injection rising channel is fixedly arranged at the top of the transformer body, a thermometer is fixedly installed at the bottom of the temperature control oil tank, and an iron core column is fixedly installed in the transformer body. The winding is fixedly installed outside the iron core column in a winding mode, the flat copper pipe is fixedly arranged in the iron core column, the oil pump is fixedly installed on one side of the bottom of the temperature control oil tank, the upper end through pipe of the flat copper pipe is connected with the hot oil injection channel, and the characteristic that hot oil floats upwards due to small density is utilized to promote the hot oil to be rapidly separated from a heating source. An aluminum alloy radiator is fixedly connected to the outer side of the winding, and wave-type radiators are fixedly arranged on the two sides of the temperature control oil tank, so that effective cooling of the interior of the transformer is achieved, and the temperature control oil tank and the winding accurately meet the heat dissipation requirement in the mode that heat is taken away through natural convection of cooling fin air and powerful wind power heat is combined.

According to the power coordination control method for the two-stage grid-forming photovoltaic converter, the two-stage grid-forming photovoltaic converter comprises a Boost module and a three-phase converter, the input side of the Boost module is connected to a photovoltaic array, the output side of the Boost module is connected to the input side of the three-phase converter, and the output side of the three-phase converter is connected to a power grid. The coordination control method is characterized by comprising the following steps: S1, acquiring an actual voltage value of a DC bus of a Boost module, and controlling the Boost module to work by adopting an MPPT algorithm based on the actual voltage value; and S2, the three-phase converter is controlled by VSG, and the difference value between the actual voltage value and the reference voltage value of the DC bus of the Boost module is used as the correction of an active loop controlled by VSG.

The invention provides a simulation method and device of a three-phase converter, computer equipment and a storage medium. According to the instantaneous value of the modulation wave and the instantaneous value of the carrier wave, the switching time of the semiconductor device in the three-phase converter from the on state to the off state and the switching time of the semiconductor device from the off state to the on state can be calculated. The switching function of each bridge arm in the three-phase current converter can be constructed according to the switching time of the semiconductor device from on to off and the switching time of the semiconductor device from off to on, and then the three-phase current converter is simulated through the switching functions. According to the method, the switch functions are given based on the two switching moments respectively, the problem of simulation errors caused by non-interpolation of the switch under fixed step length simulation can be solved, namely, the simulation errors can be reduced, and the simulation precision is improved.

This application relates to the field of power grid control and discloses a variable frequency transformer fault ride-through control method and related device for comprehensively regulating power grid voltage. The method is applied to a fault ride-through circuit, collects stator winding parameters, three-phase converter parameters, capacitor voltage, and rotor phase angle; calculates stator winding reactive power, three-phase converter positive-sequence current, and stator winding DC component based on the collected parameters; analyzes the data based on the voltage control equation to obtain the DC component of the three-phase converter's positive and negative sequence voltage reference values ​​and odd harmonic voltage reference values; analyzes the DC component of the three-phase converter's positive and negative sequence voltage reference values ​​and the three-phase converter's odd harmonic voltage reference values ​​based on the grid voltage phase angle and rotor phase angle to obtain the three-phase converter voltage vector reference value; and performs space vector modulation on the voltage vector reference value. This method addresses the current technical problem of requiring at least two three-phase converters to achieve voltage imbalance and harmonic distortion fault ride-through control, which results in high material consumption and complex operation.

The invention discloses a broadband oscillation s-domain modal analysis method for a traction power supply system. The method specifically comprises the following steps: acquiring a topological structure and element parameters of an electrified railway traction power supply system; a single-input single-output s-domain (complex frequency domain) impedance model is formed based on a small-disturbance dq impedance model of power electronic interface loads or power supplies such as locomotive and single-phase converter interface new energy; forming a system s domain node admittance matrix Y (s); in a to-be-analyzed frequency band, performing s-domain scanning on the Y (s) to obtain a system oscillation mode; calculating a damping ratio and an oscillation frequency of the oscillation mode, and a participation factor of each node to the oscillation mode; the method is suitable for broadband oscillation stability analysis of any complex topology traction power supply system containing a single-phase voltage source type converter interface power supply (new energy, energy storage and the like) and an external power system power supply. The system does not need to be divided into an active system and a passive system, and compared with a state space model, the dimensionality is low, and the engineering feasibility is good.

This invention discloses a multi-resource collaborative phase-by-phase fault self-healing method across voltage levels, belonging to the field of power grid fault self-healing. The invention includes: constructing a power supply and load information database covering the entire power grid based on the power grid's overall structure; wherein the power grid's overall structure includes faulty networks and fault-free networks across voltage levels, with the three phases of the faulty and fault-free networks connected via phase-by-phase converters; evaluating each outage node in the faulty network based on the power supply and load information database, determining the fault self-healing strategy for the current outage node; establishing an optimization model for the phase-by-phase converter switching matrix; solving the optimization model for the phase-by-phase converter switching matrix, and outputting the optimal switching matrix for the phase-by-phase converter. This invention achieves phase-by-phase power mutual assistance across voltage levels, while reducing energy waste caused by wind and solar curtailment, and improving the economic efficiency of power grid operation.

Disclosed are a phase-shifted discontinuous pulse-width modulation method and a three-phase converter. The phase-shifted discontinuous pulse-width modulation method comprises: when the three-phase converter is operating, within any switching period, switching devices of one-phase bridge arm are kept switched on or kept switched off, and a phase shift ratio delta phi exists between driver signals of the switching devices of the other two-phase bridge arms, so that at any moment a high-side switching device of each phase bridge arm in the three-phase bridge arm is not switched on or switched off at the same time. Compared with the prior art, the phase-shifted discontinuous pulse-width modulation method provided by the present invention optimizes three-phase converter efficiency on the basis of simplifying sampling circuit design and optimizing costs.