Hello Siddhi,
The information provided by you it is clear that you adjust the switching sequence so that, for example, with a sequence of [1 1 0], the inverter legs 1, 2, and 3 would be configured as: Leg 1 with the upper switch on and the lower switch off; Leg 2 with the upper switch on and the lower switch off; and Leg 3 with the upper switch off and the lower switch on. Yet, in this scenario, each state should persist for only half or one-third of the sampling time.
For this purpose you need to divide the sampling period into two intervals of T/2. For one-third the sampling time, you would divide the sampling period into three intervals of T/3.
Here's how you can implement it for each case:
1. Half the Sampling Time (T/2):
For a switching sequence [1 1 0], you would set:
0 to T/2,
- Leg 1: upper switch ON, lower switch OFF
- Leg 2: upper switch ON, lower switch OFF
- Leg 3: upper switch OFF, lower switch ON
T/2 to T,
- Leg 1: upper switch ON, lower switch OFF
- Leg 2: upper switch ON, lower switch OFF
- Leg 3: upper switch OFF, lower switch ON
2. One-Third the Sampling Time (T/3):
For a switching sequence [1 1 0], you would set:
0 to T/3,
- Leg 1: upper switch ON, lower switch OFF
- Leg 2: upper switch ON, lower switch OFF
- Leg 3: upper switch OFF, lower switch ON
T/3 to 2T/3,
- Leg 1: upper switch ON, lower switch OFF
- Leg 2: upper switch ON, lower switch OFF
- Leg 3: upper switch OFF, lower switch ON
2T/3 to T,
- Leg 1: upper switch ON, lower switch OFF
- Leg 2: upper switch ON, lower switch OFF
- Leg 3: upper switch OFF, lower switch ON
For both cases, the switching sequence [1 1 0] does not change throughout the sampling period, so the state of each leg remains the same for each interval. However, if you had a different sequence for each interval, you would implement the corresponding states for each interval.
You can setup a model in Simulink using the motor control blockset where you would typically use a combination of PWM generation blocks and logic to control the timing of the switching states.
You can refer to the below documentation by MathWorks on motor control blockset.
Hope this helps.
Regards,
Shubham Shreshth.
