GE AC Instalation and operation manual V10.docx
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The transition from the Standby state is the Enable signal or, in case of errors, a Fault signal. The
Enable signal will bring the State Machine to Precharge and eventually to the Ready state. If an
error is detected the power supply will go into Alarm state.
4.2.3.
Precharge
The Precharge is an internal transition state between Standby and Ready. During this state the
DC link is gradually charged through resistors until the rated DC link voltage is reached. The
transition will finish successfully as long as, in less than 10 seconds of precharge, the DC link has
reached the specified voltage. Otherwise, the next state will be Alarm.
The Precharge state is only applicable to the grid side converter.
4.2.4.
Ready
In the Ready state the power supply is ready to operate but no PWM signal is sent to IGBTs. The
DC bus is charged to the rectified voltage and there is no voltage/current applied to the outputs.
The transition from Ready state can be the Run signal, the Not enable signal or, in case of errors,
a Fault signal. When a Run signal is received the State Machine will evolve to the Run state.
When a Not enable signal is received the State Machine puts the power supply on standby, thus
discharging the DC link capacitors. If a fault is detected the power supply goes to Alarm state.
4.2.5.
Run
In this state, the power supply is completely operational. Due to the power supply architecture,
the grid side converter (Active Rectifier) will make the transition first while stabilizes the DC link
voltage. After that, the inverter will start the control algorithms and PWM.
This state can evolve to Standby state when a Not enable signal is received, to Ready state when
a Not run signal is received or to Alarm state if an error condition is detected.
4.2.6.
Alarm
In this state, the power supply is stopped and kept in a safe condition: the DC link is discharged
and the PWM signals are stopped.
The Alarm state can be reached by any fault detected during the normal operation of the power
supply, for instance, an emergency stop activation (see
Alarms
chapter for further detail).
The only possible transition from Alarm state is to Initialization state. Once in Alarm state a Reset
signal is required from the customer after clearing the fault condition. If the fault condition has
not been cleared the power supply state will be kept in Alarm (for example, when heatsink
overheating has occurred and the temperature is still high).
Operation modes
The GE has two operation modes:
