Abstract: An electrical converter includes first and second converter stages, an output filter, and a controller having a first mode for converting a three-phase AC signal into a DC signal. The first converter stage has a three-phase bridge rectifier connecting three phase terminals to an upper intermediate node and a lower intermediate node, and a phase selector having first switches connecting the terminals to a middle intermediate node. The second converter stage includes a switch node connected to the middle intermediate node and a pair of second switches connecting the switch node to one of the DC terminals. In a second mode, the first switches are operated while keeping the upper or lower intermediate node disconnected from all the phase terminals to allow a current to flow between the middle intermediate node and the output filter, allowing for stepwise increasing a voltage across the DC terminals during start-up.

Abstract: A voltage waveform generator for a plasma assisted processing apparatus includes a common node, a voltage supply circuit operable to switch between at least two voltage levels at a first switch node, a first inductor connected between the first switch node and the common node, and a control unit configured to operate the voltage supply circuit.

Abstract: A voltage waveform generator includes a common node, a voltage waveform generation circuit and a current source. The voltage waveform generation circuit is operably connected to the common node and is configured to apply a voltage signal at the common node. The current source is operably connected to the common node and configured to apply a DC current at the common node. The current source has a first switch node connected to the common node through a first inductor, and a first power supply connected to the first switch node. The power supply includes at least two first voltage nodes, and the current source is operable to switch between the at least two first voltage nodes at the first switch node.

Abstract: Electrical converters of the present disclosure feature a boost circuit that is fully integrated with a three phase bridge rectifier to allow for obtaining a pulsed voltage at the rectifier output. Actively switchable semiconductor switches of the boost circuit are controlled by pulse width modulation (PWM) control signals to obtain the pulsed voltage. PWM of this pulsed voltage allows control of two out of three currents at the three input terminals of the rectifier, i.e., the currents at the phase inputs having the highest and the lowest voltage levels of the three phase input voltage.

Abstract: An electrical converter for conversion between a three-phase AC signal and a DC signal may include a phase selector for connecting the three phase terminals to a first, a second, and a third intermediate node, a first buck circuit having a first switch-node terminal connected to the first DC terminal, and a second buck circuit having a second switch-node terminal connected to the second DC terminal. The first and second buck circuits convert a voltage at the first, second, and third intermediate node to a voltage between the first and second DC terminal. The first and second buck circuits are connected in series between the first and second intermediate node, and include at least one actively switchable device connected between the common node and the third intermediate node.

Abstract: A converter for converting a three-phase AC input into a DC output may include three phase input terminals and two output terminals, a phase selector for connecting the three-phase AC input to an upper intermediate node, a lower intermediate node, and a middle intermediate node. The phase selector includes semiconductor switches for selectively connecting the middle intermediate node to the three phase input terminals, and a controller. The electrical converter includes a boost circuit and a buck-boost circuit. The boost circuit includes an upper boost circuit, a lower boost circuit, and a common node. The buck-boost circuit has an output connected to the two output terminals in parallel with an output of the boost circuit, and includes at least two semiconductor switches that are actively switchable and connected in series across the output terminals. The middle intermediate node is connected to a common node of the two second semiconductor switches.

Abstract: A voltage clamp circuit for reflecting a voltage at an input node includes a circuit for providing at least two currents at its output terminal, and at least two diodes each being connected to an output terminal of the circuit for providing at least two currents. The diodes also are connected to a line of a ground voltage and to the input node respectively. The circuit includes an alternative current path connected to an output terminal of the circuit for providing at least two currents and to a current sinking node. The voltage at the input node thus is reflected as the voltage between two output nodes when the voltage at the input node is lower than a clamping voltage and so that the voltage is fixed between the two output nodes to the clamping voltage when the voltage at the input node is higher than the clamping voltage.

Abstract: A voltage clamp circuit for reflecting a voltage at an input node includes a circuit for providing at least two currents at its output terminal, and at least two diodes each being connected to an output terminal of the circuit for providing at least two currents. The diodes also are connected to a line of a ground voltage and to the input node respectively. The circuit includes an alternative current path connected to an output terminal of the circuit for providing at least two currents and to a current sinking node. The voltage at the input node thus is reflected as the voltage between two output nodes when the voltage at the input node is lower than a clamping voltage and so that the voltage is fixed between the two output nodes to the clamping voltage when the voltage at the input node is higher than the clamping voltage.