A submodule includes a bridge circuit including two main power semiconductors connected in series for performing power conversion by on/off control and an electric energy storage element connected in parallel with a path of the two main power semiconductors connected in series, a bypass unit including a bypass power semiconductor), a bypass unit drive device to drive the bypass unit, a first external terminal, and a second external terminal. The first external terminal is connected to a node between the two main power semiconductors. The power conversion apparatus further includes an optical power-feed system for feeding power to the bypass unit drive device.

An isolated communications apparatus applied to a transformer. The transformer includes N first rectifier units and a second rectifier unit, and the isolated communications apparatus includes N first control units, a second control unit, and a signal convergence unit. The first control units are connected to the first rectifier units in a one-to-one correspondence. Each first control unit is connected to the signal convergence unit, and the signal convergence unit and the second control unit are connected through an optical fiber. The signal convergence unit is configured to: receive first data packets from the N first control units, send the first data packets to the second control unit, receive at least one second data packet from the second control unit, determine a first control unit corresponding to each second data packet, and send each second data packet to a corresponding first control unit.

A master converter and a plurality of slave converters each have an input connected to an associated one of a plurality of power storage elements, respectively, and an output connected to an output terminal in parallel. The master converter converts the voltage of the associated capacitor based on a duty ratio for matching an output voltage to a voltage command value, outputs the converted voltage to the output terminal, and transmits a control signal indicative of the duty ratio to the plurality of slave converters via a signal insulation unit. Each of the plurality of slave converters converts the voltage of the associated capacitor in response to the control signal transmitted via the signal insulation unit and outputs the converted voltage to the output terminal. A correction means is configured to correct at least the duty ratio in the master converter such that the duty ratio in the master converter matches the duty ratio in each of the plurality of slave converters.

A driving and controlling method and a circuit thereof are provided. The method includes: sending, by a primary controller, a first signal that includes a first type of pulse sequence and a second type of pulse sequence; receiving the first signal, by a secondary controller, and identifying a pulse type of the first signal; when a first type of pulse is detected, the secondary controller outputs multiple switching signals to respectively control multiple switching elements to turn off; when a second type of pulse is detected, the secondary controller outputs multiple switching signals to respectively control multiple switching elements to work as normal. A level of the first signal is maintained constant between the first type of pulse sequence and the second type of pulse sequence. The disclosure features cost-efficiency and low driving delay.

A controller (3) includes an AC voltage generator (12) that generates first to Nth AC voltages, a DC voltage generator (13) that converts the first to Nth AC voltages into first to Nth DC voltages, respectively, and a driver (14) that turns on and off a switch (1) based on the first to Nth DC voltages. The AC voltage generator (12) includes first to Nth isolation transformers (T1 to TN). The primary windings of the nth and (n+1)th isolation transformers receive an AC source voltage. The nth to first isolation transformers are sequentially connected. The (n+1)th to Nth isolation transformers are sequentially connected. The first to Nth isolation transformers respectively output the first to Nth AC voltages from their respective secondary windings.

A controller and a plurality of driver circuits may be configured to operate selectively either in a normal mode or in a diagnostic mode. In the normal mode, the controller is configured to transmit a drive signal to each driver circuit via a corresponding drive signal line. Each driver circuit is configured to drive corresponding switching element(s) in response to the drive signal and is further configured to output a failure signal when the driver circuit detects a failure related to the corresponding switching element(s). In the diagnostic mode, the controller is configured to sequentially transmit a request signal to the driver circuits via their corresponding drive signal lines, and each driver circuit is configured to output the failure signal in response to the request signal in a case of having detected the failure during operation in the normal mode.

A controller and a plurality of driver circuits may be configured to operate selectively either in a normal mode or in a diagnostic mode. In the normal mode, the controller is configured to transmit a drive signal to each driver circuit via a corresponding drive signal line. Each driver circuit is configured to drive corresponding switching element(s) in response to the drive signal and is further configured to output a failure signal when the driver circuit detects a failure related to the corresponding switching element(s). In the diagnostic mode, the controller is configured to sequentially transmit a request signal to the driver circuits via their corresponding drive signal lines, and each driver circuit is configured to output the failure signal in response to the request signal in a case of having detected the failure during operation in the normal mode.

Power isolators with multiple selectable feedback modes are described. The power isolators may transfer a power signal from a primary side to a second side. A feedback signal may be provided from the secondary side to the primary side to control generation of the power signal on the primary side. In this manner, the power signal provided to the secondary side may be maintained within desired levels. The feedback signal may be generated by feedback circuitry configurable to operate in different modes, such that the feedback signal may be of differing types depending on which feedback mode is implemented.

Power isolators with multiple selectable feedback modes are described. The power isolators may transfer a power signal from a primary side to a second side. A feedback signal may be provided from the secondary side to the primary side to control generation of the power signal on the primary side. In this manner, the power signal provided to the secondary side may be maintained within desired levels. The feedback signal may be generated by feedback circuitry configurable to operate in different modes, such that the feedback signal may be of differing types depending on which feedback mode is implemented.

To suppress a leakage current flowing through a parasitic capacitor of an insulated transformer of a high-side insulated power. The present invention suppresses a common mode current using a common mode reactor by focusing on the fact that a leakage current flowing through a parasitic capacitor of an insulated transformer of a high-side insulated power source resulting from a high-frequency signal generated due to an on/off operation of a high-side switching element is the common mode current. The common mode reactor reduces the common mode current and bears the high-frequency signal to prevent the high-frequency signal from being applied to the insulated transformer of the high-side insulated power source, suppress the leakage current flowing through the parasitic capacitor of the insulated transformer, and reduce an erroneous operation of the high-side switching element generated due to the leakage current flowing through the parasitic capacitor of the insulated transformer.