Question

What are the names of Z-parameters?

Answer 1

Could you clarify if you're referring to Z-parameters in electrical engineering or a different field?

Answer 2

Z-parameters, also known as impedance parameters, are used in electrical engineering to describe the electrical behavior of linear two-port networks. They are particularly useful in analyzing and designing circuits involving resistors, capacitors, and inductors.

Here are the names and definitions of the Z-parameters for a two-port network:

1. **\( Z_{11} \)**: **Input Impedance** – This parameter represents the impedance looking into the input port (port 1) when the output port (port 2) is open (i.e., no load connected). It is defined as:
   \[
   Z_{11} = \frac{V_1}{I_1} \text{ when } I_2 = 0
   \]
   where \( V_1 \) is the voltage at port 1 and \( I_1 \) is the current entering port 1.

2. **\( Z_{12} \)**: **Reverse Transfer Impedance** – This parameter represents the impedance from the input port (port 1) to the output port (port 2). It is defined as:
   \[
   Z_{12} = \frac{V_1}{I_2} \text{ when } I_1 = 0
   \]
   where \( I_2 \) is the current entering port 2.

3. **\( Z_{21} \)**: **Forward Transfer Impedance** – This parameter represents the impedance from the output port (port 2) to the input port (port 1). It is defined as:
   \[
   Z_{21} = \frac{V_2}{I_1} \text{ when } I_2 = 0
   \]
   where \( V_2 \) is the voltage at port 2.

4. **\( Z_{22} \)**: **Output Impedance** – This parameter represents the impedance looking into the output port (port 2) when the input port (port 1) is open. It is defined as:
   \[
   Z_{22} = \frac{V_2}{I_2} \text{ when } I_1 = 0
   \]
   where \( I_2 \) is the current entering port 2.

In summary:

- **\( Z_{11} \)**: Input impedance (when the output is open)
- **\( Z_{12} \)**: Reverse transfer impedance (input voltage with output current)
- **\( Z_{21} \)**: Forward transfer impedance (output voltage with input current)
- **\( Z_{22} \)**: Output impedance (when the input is open)

These parameters are especially useful for analyzing and designing networks and can be used in various calculations involving network behavior, stability, and performance.