39 results about "Unbalanced line" patented technology

A balanced splitter has six ¼ strip lines. The first and third strip lines are electromagnetically coupled to each other to form a coupler. The second and fourth strip lines are electromagnetically coupled to each other to form a coupler. The first and fifth strip lines are electromagnetically coupled to each other to form a coupler. The second and sixth strip lines are electromagnetically coupled to each other to form a coupler. The first and second strip lines are connected in series to form an unbalanced line, the third and fourth strip lines form a first balanced line, and the fifth and sixth strip lines form a second balanced line. First and second resistors are electrically connected between a first balanced terminal and a second balanced terminal, and between another first balanced terminal and another second balanced terminal, respectively.

A comprehensive evaluation method for the line loss level of a low-voltage transformer area comprises the steps as follows: equivalent resistance of distribution lines in the low-voltage transformer area is calculated respectively; the line loss rate and head end average load current of a low-voltage circuit are measured; a load curve characteristic coefficient and a three-phase unbalanced line loss correction coefficient are calculated respectively; the theoretic line loss rate in the low-voltage transformer area is calculated, and the measured line loss rate and the theoretic line loss rate are compared, so that the management line loss level in the low-voltage transformer area is judged; and the like, wherein the head end average load current, the load curve characteristic coefficient, the three-phase unbalanced line loss correction coefficient and the like are calculated along with a calculation method of the theoretic line loss of the to-be-calculated low-voltage transformer area after a simultaneous equation set is established. According to the method, the parameters and a management line loss evaluation threshold can be accurately calculated, and comprehensive evaluation of the line loss level of the low-voltage transformer area can be accurately completed further; and particularly, when electricity stealing and leakage conditions occur, the method can accurately judge the line loss level, and misjudgments are avoided.

The invention relates to a three-phase imbalance adjustment control method, a three-phase imbalance adjustment control device and a three-phase imbalance adjustment system. The actual value of three-phase imbalance is obtained according to the current of the maximum current phase and the current of the minimum current phase in currents of three phases collected, and is sent to an outer voltage loop. Then, the difference between the actual value of three-phase imbalance and a given value of three-phase imbalance is calculated. Through voltage and current closed-loop control and positive / negative-sequence dq / abc coordinate transformation, total modulating wave for making active power compensation from the maximum current phase to the minimum current phase is generated, and a control signal for adjusting the active power is generated after modulation. According to the invention, the electric energy of the three phases is redistributed according to the load demand, electric energy can be switched fast between unbalanced lines, and three-phase imbalance at the output side of a power distribution transformer can be adjusted quickly and smoothly. Moreover, the loss of power distribution lines can be reduced effectively, the output power of power distribution transformers and the safety operation ability of the power distribution system are improved, and the quality of power supply to users is improved.

In a balun for mutually converting an unbalanced line for unbalanced input / output and a balanced line for balanced input / output, the unbalanced line and the balanced line are microstrip lines including a signal line arranged on one main surface of a substrate and a ground conductor arranged on the other main surface of the substrate. The balun further includes a slot line formed by a aperture line arranged in the ground conductor in the other main surface. The microstrip line as the unbalanced line includes one end portion used as an input / output end and the other end portion that traverses the slot line, electromagnetically couples to the slot line, and functions as an electric short-circuited end. The central portion of the microstrip line as the balanced line traverses the slot line and electromagnetically couples to the slot line. Both ends of this microstrip line serves as the input / output ends.

A balanced splitter has six ¼ strip lines. The first and third strip lines are electromagnetically coupled to each other to form a coupler. The second and fourth strip lines are electromagnetically coupled to each other to form a coupler. The first and fifth strip lines are electromagnetically coupled to each other to form a coupler. The second and sixth strip lines are electromagnetically coupled to each other to form a coupler. The first and second strip lines are connected in series to form an unbalanced line, the third and fourth strip lines form a first balanced line, and the fifth and sixth strip lines form a second balanced line. First and second resistors are electrically connected between a first balanced terminal and a second balanced terminal, and between another first balanced terminal and another second balanced terminal, respectively.

The present invention is directed to an amplifier system that includes a main amplifier configured to amplify and a peak amplifier that operates only in a high power mode. An impedance matching network is coupled to at least the peak power amplifier. An impedance transformation device is coupled to at least a portion of the impedance matching network. The impedance transformation device is configured as a balun in the high power mode. The balun includes a first input and second input coupled to the main amplifier and the peak amplifier respectively. The impedance transformation device is configured as an unbalanced line impedance transformer in the low power mode because the predetermined output impedance substantially grounds the second input. The Doherty device is characterized by an impedance transformation ratio of at least 4:1 and a relative bandwidth greater than or equal to 40%.

In a balun for mutually converting an unbalanced line for unbalanced input / output and a balanced line for balanced input / output, the unbalanced line and the balanced line are microstrip lines including a signal line arranged on one main surface of a substrate and a ground conductor arranged on the other main surface of the substrate. The balun further includes a slot line formed by a aperture line arranged in the ground conductor in the other main surface. The microstrip line as the unbalanced line includes one end portion used as an input / output end and the other end portion that traverses the slot line, electromagnetically couples to the slot line, and functions as an electric short-circuited end. The central portion of the microstrip line as the balanced line traverses the slot line and electromagnetically couples to the slot line. Both ends of this microstrip line serves as the input / output ends.

An unbalanced line-to-line current is injected at an injected frequency in a three-phase ac circuit. A first set of voltages and currents are obtained. A first set of transformed voltages and transformed currents are produced. The circuit is injected with a second unbalanced line-to-line current at a frequency linearly independent of the injected frequency. A second set of voltages and current are obtained. A second set of transformed voltages and transformed currents are produced The impedance of a source portion and a load portion of the circuit are calculated using the first and second set of transformed voltages, and the first and second set of transformed currents.

The present invention is directed to an amplifier system that includes a main amplifier configured to amplify and a peak amplifier that operates only in a high power mode. An impedance matching network is coupled to at least the peak power amplifier. An impedance transformation device is coupled to at least a portion of the impedance matching network. The impedance transformation device is configured as a balun in the high power mode. The balun includes a first input and second input coupled to the main amplifier and the peak amplifier respectively. The impedance transformation device is configured as an unbalanced line impedance transformer in the low power mode because the predetermined output impedance substantially grounds the second input. The Doherty device is characterized by an impedance transformation ratio of at least 4:1 and a relative bandwidth greater than or equal to 40%.

An example of a transmission-line transformer may include a transmission-line assembly and a balun assembly. The transmission-line assembly may include first and second conductors forming at least first and second transmission-line sections. The transmission-line assembly may provide a signal path through the first conductor and second conductor in series to a circuit ground. Balanced lines of the balun assembly may be connected to respective intermediate points on the first and second conductors between the first and second transmission-line sections. The transmission-line transformer may provide a signal path between a first end of the first conductor of the transmission-line assembly and the unbalanced line of the balun assembly.

The present invention relates to a system to implement a phase-locked loop (PLL) which is able to provide an estimation of the angular frequency, and both the positive and negative sequences of the fundamental component of a three-phase signal. These sequences are provided in fixed reference frame coordinates.

A control method for photovoltaic power generation and power grid three-phase balance is implemented by a measurement and control device and a power grid treatment device and comprises the steps of 1,judging a power flow direction of a power grid according to a power read by the measurement and control device, wherein power is supplied to a load from the power grid when the power is positive, andthe power is fed to the power grid by photovoltaic power generation when the power is negative; 2, performing average value calculation on the read three-phase power grid by the measurement and control device; 3, judging a phase circuit with maximum power supplied from the power grid to the load or maximum power fed to the power grid by photovoltaic power generation when the three-phase power isunbalanced; 4, calculating a power allocation coefficient of each power grid treatment device in the three-phase unbalanced line; 5, calculating a power allocation value of each power grid treatment device in the three-phase unbalanced line; and 6, controlling the corresponding power grid treatment devices to output or absorb the power by the measurement and control device according to the power allocation value of the power grid treatment device. By the control method, the purpose of three-phase power balance of the power grid is achieved.

PROBLEM: To provide a high-performance complex circuit, circuit device, circuit board, and communication device that support a wider band of frequencies.SOLUTION: A complex circuit includes a first diplexer that passes through the normal-phase signals of balanced signals and a second diplexer that passes through the reverse-phase signals of the balanced signals. A balun includes a low frequency band first balun element and a high frequency band second balun element. The first balun element and the second balun element respectively include a plurality of lines that are connected to the first diplexer and that carry signals occupying two different frequency bands and also respectively include a plurality of lines that are connected to the second diplexer and that carry signals occupying two different frequency bands. The lines form one pair of balanced lines, and the lines form another pair of balanced lines. Furthermore, the first balun element and the second balun element each include an unbalanced line.

The invention discloses an energy-saving device based on low-voltage line load balance. The energy-saving device comprises a low-voltage master control switch, wherein the first end of the low-voltage master control switch is connected with the secondary side of a transformer, a primary side of the transformer is used for being connected with the power grid power supply end, the second end of the low-voltage master control switch is connected into a low-voltage bus, a multiple balance power distribution lines are further connected onto the low-voltage bus and are series circuits formed by sequentially connecting a wire outlet switch and N sectioned switches, the wire outlet switch is connected into the low-voltage bus, and the tail ends between every two balance power distribution lines are connected through an interconnection switch and form a low-voltage loop. The low-voltage master control switch and the wire outlet switch on each low-voltage master control switch are connected with a load balance controller through an independent communication channel, and the N sectioned switches on each balance power distribution line are connected with the load balance controller through an independent communication channel. The line heavy load or overload problem caused by unbalanced line load is solved, and the whole line outage caused by faults or overhauling is avoided.

A filter arrangement includes one first resonator circuit connected between a first node and a second node. A second resonator circuit is connected between a third node and a fourth node. The first resonator circuit and the second resonator circuit are intercoupled. Further, an inductive device is provided, connected between the first node and the third node.

A high-frequency composite component is provided by placing an antenna on a multi-layer wiring board, placing a multiplexer / demultiplexer circuit, first and second matching circuits, and first and second balanced-to-unbalanced transformer circuits inside the board respectively, and providing first to fourth input and output terminals on the side surface of the board. The antenna is connected to the multiplexer / demultiplexer circuit via a first unbalanced line path, and the multiplexer / demultiplexer is connected to the first and second matching circuits via second and third unbalanced line paths, respectively. The first and second matching circuits are connected to the first and second balanced-to-unbalanced transformer circuits, respectively, via fourth and fifth unbalanced line paths, respectively. The respective balanced terminals of the first and second balanced-to-unbalanced transformer circuits are connected to the first and second, and third and fourth input and output terminals, respectively, via first and second balanced line paths, respectively.

A balun circuit is provided that includes a first coupling line in which an unbalanced line thereof is connected to a first terminal and a balanced line thereof is electrically connected to a second terminal, a second coupling line in which an unbalanced line thereof is electrically connected to the unbalanced line of the first coupling line and a balanced line thereof is electrically connected to a third terminal, a first transmission path that is serially connected between the balanced line of the first coupling line and a ground potential, a second transmission path that is serially connected between the balanced line of the second coupling line and a ground potential, and a third transmission path that is serially connected between the unbalanced line of the first coupling line and the unbalanced line of the second coupling line. These transmission lines are formed such that an amplitude characteristic of S12 is the same as an amplitude characteristic of S13 and a phase characteristic of S12 is inverted in relation to a phase characteristic of S13.

The invention provides a three-phase voltage unbalance degree determination method and device for a wind power collection area. The method comprises the steps of determining a three-phase impedance matrix of an unbalanced line according to line parameters of the wind power collection area; establishing an equivalent model according to power grid parameters and a topological structure of the wind power collection area, and determining three-phase voltage and three-phase current of an equivalent node in the equivalent model; determining a positive sequence voltage and a negative sequence voltageof an equivalent node of the wind power collection area according to the three-phase impedance matrix, the three-phase voltage of the equivalent node and the three-phase current; and determining thethree-phase voltage unbalance degree of the wind power collection region according to the determined positive sequence voltage and negative sequence voltage of the equivalent node of the wind power collection region. By utilizing the method, the key factors influencing the three-phase voltage imbalance of the wind power plant can be simply and clearly analyzed, and the method has important guidingsignificance for exploring the voltage imbalance mechanism of a large-scale wind power collection region.

A balun device provides a more suitable technique for a broader band application which has been difficult for conventional baluns. The balun device has a balun unit, which is provided with a balanced line and an unbalanced line, and a matching circuit connected to the unbalanced line, wherein the matching circuit is composed of a high-pass filter.

An unbalanced line-to-line current is injected at an injected frequency in a three-phase ac circuit. A first set of voltages and currents are obtained. A first set of transformed voltages and transformed currents are produced. The circuit is injected with a second unbalanced line-to-line current at a frequency linearly independent of the injected frequency. A second set of voltages and current are obtained. A second set of transformed voltages and transformed currents are produced The impedance of a source portion and a load portion of the circuit are calculated using the first and second set of transformed voltages, and the first and second set of transformed currents.

The present invention comprises baluns 2a, 2b which convert balanced line signals and unbalanced line signals mutually, and filters 3a, 3b which are electrically connected to the baluns 2a, 2b and pass or attenuate the predetermined frequency bands. Electrode layers 15a-22a, 25a, 41, 42, 43 which compose the electrode patterns of the baluns 2a, 2b and the filters 3a, 3b, and the dielectric layers 30-39 are integrally stacked.

A balun includes an unbalanced terminal, balanced terminals, and lines, and converts a signal between an unbalanced line and an balanced line. A first line is connected between the unbalanced terminal and a reference potential. A second line is connected between the balanced terminal and the reference potential, and is coupled to the first line. A third line is connected between the balanced terminal and the reference potential, and is coupled to the first line. A fourth line is connected in parallel to the second line, and is coupled to the third line. The fourth line is configured such that a signal with an opposite phase to that of a signal passing through the third line passes through the fourth line.

A power amplifying circuit includes a first amplifier, a second amplifier, a transformer having a primary winding and a secondary winding, and a capacitor. The first amplifier amplifies a signal which is one of differential signals. The second amplifier amplifies a signal which is the other of the differential signals. The primary winding is connected, at its first end, to the first amplifier, and is connected, at its second end, to the second amplifier. The secondary winding is connected, at its first end, to an unbalanced line through which an unbalanced signal is transmitted, and is connected, at its second end, to the ground. The secondary winding is electromagnetically coupled to the primary winding. The capacitor is connected, at its first end, to the midpoint of the primary winding, and is connected, at its second end, to the ground.