The present invention discloses an electrical discharge circuit having stable discharging mechanism. A voltage-dividing circuit generates a detection signal such that a first inverter outputs an inverted detection signal. A first PMOS and a first NMOS are coupled through a first terminal between the voltage input terminal and a ground terminal. A second NMOS is coupled between a second terminal and the ground terminal. A first PMOS control terminal is coupled to the second terminal. A first and a second NMOS control terminals respectively receive the inverted detection signal and the detection signal. A resistor and a capacitor are coupled through the control terminal coupled to the second terminal and between the voltage input terminal and the ground terminal. A second inverter receives an inverted boosted detection signal from the control terminal to output a boosted detection signal to control an electrostatic discharge MOS to discharge the voltage input terminal.

The present invention discloses an electrical discharge circuit having stable discharging mechanism. A voltage-dividing circuit generates a detection signal such that a first inverter outputs an inverted detection signal. A first PMOS and a first NMOS are coupled through a first terminal between the voltage input terminal and a ground terminal. A second NMOS is coupled between a second terminal and the ground terminal. A first PMOS control terminal is coupled to the second terminal. A first and a second NMOS control terminals respectively receive the inverted detection signal and the detection signal. A resistor and a capacitor are coupled through the control terminal coupled to the second terminal and between the voltage input terminal and the ground terminal. A second inverter receives an inverted boosted detection signal from the control terminal to output a boosted detection signal to control an electrostatic discharge MOS to discharge the voltage input terminal.

[Problem] An object is to provide an inverter circuit that can improve the efficiency and stabilize the operation, the inverter circuit executes normal control when the output voltage rises, even when the output frequency is low, and the inverter circuit divides the normal control and regenerative control operations so that the regenerative control is executed when the output voltage drops. [Solution] When the error value is greater than or equal to the first threshold value, the control unit of the inverter circuit executes a normal control of the capacitive load, by operating the primary side switch with the secondary side switch turned off, and on the other hand, when the error value is less than the first threshold value, the control unit executes a regenerative control to the direct current power supply, by operating the secondary side switch with the primary side switch turned off.

[Problem] An object is to provide an inverter circuit that can improve the efficiency and stabilize the operation, the inverter circuit executes normal control when the output voltage rises, even when the output frequency is low, and the inverter circuit divides the normal control and regenerative control operations so that the regenerative control is executed when the output voltage drops. [Solution] When the error value is greater than or equal to the first threshold value, the control unit of the inverter circuit executes a normal control of the capacitive load, by operating the primary side switch with the secondary side switch turned off, and on the other hand, when the error value is less than the first threshold value, the control unit executes a regenerative control to the direct current power supply, by operating the secondary side switch with the primary side switch turned off.

A method for controlling an electrical converter comprises the acts of determining an error value based on a difference between an estimated output value and a reference output value, the estimated output value being based on measurements in the electrical converter; comparing the error value with an error band and in the case of the error value exceeds the error band, controlling the electrical converter by switching to a different control scheme. The converter is controlled with the modified pre-calculated switching by determining a pre-calculated switching sequence for the converter based on an actual state of the electrical converter, the switching sequence comprising a sequence of switching transitions of the converter; modifying the pre-calculated switching sequence by modifying transition times of switching transitions of the pre-calculated switching sequence, such that the error value is minimized; and applying at least a part of the modified switching sequence to the electrical converter.

An inverter comprises a first switch coupled to an input of an output filter and a positive dc bus, a second switch coupled to the input of the output filter and a negative dc bus, a first freewheeling apparatus coupled to the first switch, the second switch and ground, a first soft switching network coupled to the first freewheeling apparatus and the first switch, wherein the first soft switching network is configured such that the first switch is of a first zero voltage transition during a turn-on process of the first switch and a second soft switching network coupled to the first freewheeling apparatus and the second switch, wherein the second soft switching network is configured such that the second switch is of a second zero voltage transition during a turn-on process of the second switch.

An inverter comprises a first switch coupled to an input of an output filter and a positive dc bus, a second switch coupled to the input of the output filter and a negative dc bus, a first freewheeling apparatus coupled to the first switch, the second switch and ground, a first soft switching network coupled to the first freewheeling apparatus and the first switch, wherein the first soft switching network is configured such that the first switch is of a first zero voltage transition during a turn-on process of the first switch and a second soft switching network coupled to the first freewheeling apparatus and the second switch, wherein the second soft switching network is configured such that the second switch is of a second zero voltage transition during a turn-on process of the second switch.

A controller switches between modes each having a different connection state of a DC power supply and the capacitor with respect to first and second output points by controlling switches. A generation unit generates a reference wave including at least one carrier wave. The modes are classified into a sustaining mode in which no current is caused to flow to the capacitor, a charging mode in which a current is caused to flow to the capacitor, and a discharging mode in which a current in a direction opposite to that in the charging mode is caused to flow to the capacitor. The controller switches between the sustaining mode and a charging or discharging mode according to the comparison result between a signal wave and the reference wave.

A controller switches between modes each having a different connection state of a DC power supply and the capacitor with respect to first and second output points by controlling switches. A generation unit generates a reference wave including at least one carrier wave. The modes are classified into a sustaining mode in which no current is caused to flow to the capacitor, a charging mode in which a current is caused to flow to the capacitor, and a discharging mode in which a current in a direction opposite to that in the charging mode is caused to flow to the capacitor. The controller switches between the sustaining mode and a charging or discharging mode according to the comparison result between a signal wave and the reference wave.

A control method of controlling a resonance type power conversion device including a voltage resonance circuit is provided. The voltage resonance circuit comprising, a choke coil connected to input power supply, a first switching element connected to the choke coil, a capacitor connected in parallel to the first switching element, and a resonance circuit connected between a connection point and an output terminal, the connection point being a point at which the choke coil and the first switching element are connected. The control method comprising, detecting a polarity of current flowing through parallel circuit connected in parallel to the first switching element by using a sensor included in the voltage resonance circuit; and controlling an operating condition of the first switching element depending on a polarity of the current detected by the sensor.