Abstract: The battery includes a cell pack. The detection circuit includes a first switch unit, a second switch unit, a discharge unit, a sampling unit, an energy storage unit, and a controller. A first terminal of the first switch unit is connected to a first terminal of the cell pack. A second terminal of the first switch unit is connected to a second terminal of the cell pack after being connected in series to the energy storage unit. The second switch unit is connected in parallel to the energy storage unit after being connected in series to the discharge unit. The discharge unit discharges the energy storage unit. The sampling unit is connected in parallel to the energy storage unit. The sampling unit sends an obtained sampling signal to the controller.

Abstract: A resonant converter and a voltage conversion method. The resonant converter includes a high-frequency inversion circuit, an inductor-inductor-capacitor (LLC) resonant tank network, and a hybrid rectification circuit. The LLC resonant tank network is separately coupled to the high-frequency inversion circuit and the hybrid rectification circuit. The high-frequency inversion circuit is configured to convert a first direct current voltage into a first alternating current voltage. The LLC resonant tank network is configured to adjust the first alternating current voltage to obtain a second alternating current voltage.

Abstract: In a sampling circuit, a single cell in a series battery pack is isolated from a voltage divider resistor in a bleeder circuit by using a first isolation sampling switch, so as to prevent a drain current of the single cell. In addition, sampling errors in sampling voltages collected by the sampling circuit may be offset during differential calculation.

Abstract: A sampling circuit, an equalization circuit, and a system for a single cell in a series battery pack are provided. In the sampling circuit provided in this disclosure, the single cell is isolated from a voltage divider resistor in the bleeder circuit by using the first isolation sampling switch, so as to prevent a drain current of the single cell. In addition, sampling errors in sampling voltages collected by the sampling circuit may be offset during differential calculation.

Abstract: The present invention provides a resonant bidirectional converter, an uninterruptible power supply apparatus, and a control method. The resonant bidirectional converter includes: a filter capacitor, three primary side bridge arms, a resonant cavity, three transformers, and three secondary side bridge arms, where two ends of each of the primary side bridge arms are separately connected to two ends of a bus capacitor, each of the primary side bridge arms includes two semiconductor switch that are serially connected in a same direction, and any connection point located between the two semiconductor switch of the primary side bridge arm that are serially connected in the same direction is a first connection point.

Abstract: A power conversion circuit includes: an AC-DC circuit, a direct current-alternating current DC-AC circuit, and a first filter capacitor. The DC-AC circuit includes: a third bridge arm, a fourth bridge arm, a first inductor, a second inductor, a first switch transistor, and a second switch transistor, a second end of the first inductor is connected to a first end of the first switch transistor, a second end of the first switch transistor is connected to the direct current bus, a first end of the second inductor is connected to a connection point of two switch transistors included by the fourth bridge arm, a second end of the second inductor is connected to a first end of the second switch transistor, and a second end of the second switch transistor is connected to the direct current bus.

Abstract: A resonant conversion circuit includes resonant conversion circuit units having at least two phases interleaved in parallel, where magnetic devices in the resonant conversion circuit units are magnetically integrated in an inter-phase manner on a same magnetic core. Because a magnetic coupling action exists between the magnetic devices integrated on the same magnetic core, automatic current sharing effect is produced on currents in circuit branches of different phases. In this way, current sharing of the resonant conversion circuit units of various phases is achieved, and the volume of a power supply is reduced because of integration of the magnetic devices.

Abstract: A power factor correction converter and a power factor correction conversion device, includes two groups of bidirectional switches, an autotransformer, a boost inductor, a bus filter capacitor, two front bridge arms; and a rear bridge arm; the front end of each group of bidirectional switches are connected to a coil of the autotransformer in one-to-one correspondence, and a rear end of each group of bidirectional switches is connected to one end of an AC input power grid; a central tap of the autotransformer is connected to an output end of the boost inductor, and an input end of the boost inductor is connected to the other end of the AC input power grid; a front end of each group of bidirectional switches is connected to a front bridge arm, and a rear end is connected to the rear bridge arm.

Abstract: A power factor correction converter and a power factor correction conversion device, includes two groups of bidirectional switches, an autotransformer, a boost inductor, a bus filter capacitor, two front bridge arms; and a rear bridge arm; the front end of each group of bidirectional switches are connected to a coil of the autotransformer in one-to-one correspondence, and a rear end of each group of bidirectional switches is connected to one end of an AC input power grid; a central tap of the autotransformer is connected to an output end of the boost inductor, and an input end of the boost inductor is connected to the other end of the AC input power grid; a front end of each group of bidirectional switches is connected to a front bridge arm, and a rear end is connected to the rear bridge arm.