Paralleling power semiconductors with different switching frequencies
Various examples are provided related to operation of parallel semiconductors with different switching frequencies. In one example, a method of reducing conduction and switching losses in a high current switching circuit includes controlling two hybrid switches to conduct concurrently or alternately, each of the hybrid switches include a wide bandgap device and a silicon power device. Controlling of the silicon power device is at a first gate switching frequency and controlling of the wide bandgap device is at a second gate switching frequency, where the first gate switching frequency is lower than the second gate switching frequency. The silicon power device can be switched at a frequency of about 50 or 60 Hertz. The wide bandgap device can be switched at a frequency greater than 1 kHz.
1 . A method of reducing conduction and switching losses in a high current switching circuit, comprising:
controlling two hybrid switches to conduct concurrently or alternately, the two hybrid switches connected in series, wherein each of said two hybrid switches comprise a wide bandgap device and a silicon power device connected in parallel, controlling of the silicon power device in a selective ON-OFF mode without pulse width modulation (PWM) at a first gate switching frequency and controlling of the wide bandgap device in a PWM mode at a second gate switching frequency, where the first gate switching frequency is lower than the second gate switching frequency, wherein the silicon power device is controlled at the first gate switching frequency while the wide bandgap device is in an off state and the wide bandgap device is controlled at the second gate switching frequency while the silicon power device is in an off state.
2 . The method of claim 1 , wherein the silicon power device is switched at the first gate switching frequency of about 50 or 60 Hertz.
3 . The method of claim 1 , wherein said two hybrid switches form a half-bridge circuit.
4 . The method of claim 1 , wherein two additional hybrid switches are controlled to conduct alternately in a full bridge circuit.
5 . The method of claim 1 , wherein said two hybrid switches form a phase leg of a multi-phase power converter.
6 . The method of claim 1 , wherein four additional hybrid switches are controlled to conduct in a three-phase circuit.
7 . The method of claim 2 , wherein the wide bandgap device is switched at the second switching frequency greater than 1 kHz.
8 . The method of claim 2 , wherein said two hybrid switches form a half-bridge circuit.
9 . The method of claim 2 , wherein two additional hybrid switches are controlled to conduct alternately in a full bridge circuit.
10 . The method of claim 2 , wherein said two hybrid switches form a phase leg of a multi-phase power converter.
11 . The method of claim 2 , wherein four additional hybrid switches are controlled to conduct in a three-phase circuit.
12 . The method of claim 7 , wherein the wide bandgap device is switched at the second switching frequency of about 20 kHz.
13 . The method of claim 7 , wherein said two hybrid switches form a half-bridge circuit.
14 . The method of claim 7 , wherein two additional hybrid switches are controlled to conduct alternately in a full bridge circuit.
15 . The method of claim 7 , wherein said two hybrid switches form a phase leg of a multi-phase power converter.
16 . The method of claim 12 , wherein said two hybrid switches form a half-bridge circuit.
17 . The method of claim 12 , wherein two additional hybrid switches are controlled to conduct alternately in a full bridge circuit.
18 . The method of claim 12 , wherein said two hybrid switches form a phase leg of a multi-phase power converter.
19 . The method of claim 12 , wherein four additional hybrid switches are controlled to conduct in a three-phase circuit.