Impulse voltage generation device
A signal generator generates a combined signal that is generated only in the period where supply of a pulse signal is effected, a pulse signal whose frequency is of a higher impulse repetition frequency than the frequency of the period setting signal and whose amplitude represents a voltage value that is lower than the high voltage HVDC value. A semiconductor switch accumulates electric charge on a capacitative element by means of the high voltage HVDC from the high voltage generator when the voltage value of the combined signal is lower than the set gate voltage value and generates an impulse voltage whose peak value is the value of the high voltage HVDC, by means of the electric charge that is discharged from the capacitative element when the voltage value of the combined signal exceeds the set gate voltage value.
1. An impulse voltage generation device comprising:
a high voltage generator for generating a high voltage;
a capacitive element;
a signal generator for generating a combined signal that is generated only in a period where supply of a pulse signal is effected by superimposing a period setting signal whereof one cycle includes a pulse supply period and a pulse idling period subsequent to the pulse supply period on a pulse signal whose frequency is an impulse repetition frequency higher than the frequency of the period setting signal and whose amplitude represents a voltage value that is lower than the high voltage value; and
a semiconductor switch for accumulating electric charge on the capacitive element by means of the high voltage from the high voltage generator when the voltage value of the combined signal is lower than the set gate voltage value, generating an impulse voltage whose peak value is the value of the high voltage by means of the electric charge that is discharged from the capacitive element when the voltage value of the combined signal exceeds the set gate voltage value and supplying the impulse voltage between the first output terminal and the second output terminal where a load is provided.
2. The impulse voltage generation device according to claim 1 , wherein
the output of the high voltage generator is connected to the first electrode of the capacitive element; and
the semiconductor switch has: a first terminal connected to the first electrode of the capacitive element, a second terminal connected to the first output terminal, and a gate terminal connected to the output of the signal generator such that
the semiconductor switch is configured to disconnect the first electrode of the capacitive element and the first output terminal by way of the semiconductor switch when the voltage value of the combined signal supplied to the gate terminal is lower than the set gate voltage value, so as to accumulate electric charge between the first electrode and the second electrode of the capacitive element by means of the high voltage from the high voltage generator, but
the semiconductor switch is configured to connect the first electrode of the capacitive element and the first output terminal by way of the semiconductor switch when the voltage value of the combined signal supplied to the gate terminal is not lower than the set gate voltage value to discharge the electric charge accumulated in the capacitive element, so as to generate the impulse voltage whose peak value is equal to the high voltage value by means of the electric charge discharged from the capacitive element, and to supply the impulse voltage between the first output terminal and the second output terminal that is at an electric potential level same as the electric potential level of the second electrode of the capacitive element.
3. The impulse voltage generation device according to claim 2 , further comprising:
an electric charging resistance element that is a resistance element arranged between the output of the high voltage generator and the first electrode of the capacitive element;
a load resistance element that is a resistance element arranged between the first output terminal and the second output terminal; and
an adjusting resistance element that is a resistance element arranged between the second terminal of the semiconductor switch and the first output terminal.
4. The impulse voltage generation device according to claim 2 , further comprising:
a switch inverse voltage protection diode whose cathode and anode are connected respectively to the first terminal and the second terminal of the semiconductor switch.
5. The impulse voltage generation device according to claim 1 , further comprising:
a DC power source for generating a DC voltage;
the high voltage generator being adapted to generate a high voltage that is proportional to the DC voltage supplied from the DC power source and higher than the DC voltage.
6. The impulse voltage generation device according to claim 5 , wherein
the DC power source is configured to supply the DC voltage to the high voltage generator according to a voltage value, a rising time and a falling time that are specified in advance to control the high voltage.
7. The impulse voltage generation device according to claim 6 , wherein
the DC power source is configured:
to supply a first DC voltage that is a DC voltage proportional to the first high voltage in order to cause the high voltage generator to generate the first high voltage that is a high voltage during a first pulse supply period, which is the above defined pulse supply period; and also
to supply the second DC voltage that is a DC voltage proportional to the second high voltage in order to cause the high voltage generator to generate a second high voltage that differs from the first high voltage during a second pulse supply period that comes next to the first pulse supply period.
8. The impulse voltage generation device according to claim 1 , wherein
the impulse voltage generation device is configured so as to be employed to evaluate a system comprising a rotary electric machine, an inverter for outputting a pulse voltage to drive the rotary electric machine and a cable connecting the inverter and the rotary electric machine or to evaluate a coil part of the rotary electric machine in the system; and
the high voltage is a voltage determined by assuming the peak voltage value of inverter surge that can arise at a connecting section where the cable is connected to the rotary electric machine or a value obtained by multiplying the peak voltage value by a safety factor, while
the impulse repetition frequency is a frequency determined by assuming instances where inverter surges occur repeatedly.
9. The impulse voltage generation device according to claim 1 , wherein
the impulse voltage generating device is configured to be employed to evaluate a system comprising a linear motor, an inverter for outputting a pulse voltage to drive the linear motor and a cable connecting the inverter and the linear motor or to evaluate a coil part of the linear motor in the system; and
the high voltage is a voltage determined by assuming the peak voltage value of inverter surge that can arise at a connecting section where the cable is connected to the rotary electric machine or a value obtained by multiplying the peak voltage value by a safety factor, while
the impulse repetition frequency is a frequency determined by assuming instances where inverter surges occur repeatedly.
10. The impulse voltage generation device according to claim 1 , further comprising:
a load inverse voltage protection diode whose cathode and anode are connected respectively to the first output terminal and the second output terminal,
the load inverse voltage protection diode being arranged in parallel with the load.