0%
Filled with laugh-out-loud hilarious text and cartoons, the Diary of a Wimpy Kid series follows Greg Heffley as he records the daily trials and triumphs of friendship, family life and middle school where undersized weaklings have to share the hallways with kids who are taller, meaner and already shaving! On top of all that, Greg must be careful to avoid the dreaded CHEESE TOUCH!
The first book in the series was published in 2007 and became instantly popular for its relatable humor. Today, more than 300 million copies have been sold around the world!
| Winding | Current (A) | Bare area (mm²) | Wire dia bare (mm) | Wire dia insulated (mm) | Turns | Build (mm) | |---------|-------------|----------------|---------------------|--------------------------|-------|-------------| | Primary | =VA/(η*Vp) | =I/J | =SQRT(4*Aw/π) | from table | Np | =turns * insulated_dia | | Secondary | Is | =Is/J | ... | ... | Ns | ... |
[ N_s = \fracV_s \cdot (1 + reg/100)V_p \cdot N_p ] where (reg) = regulation (e.g., 5%).
| Parameter | Symbol | Typical Value | Unit | |-----------|--------|---------------|------| | Primary voltage (RMS) | ( V_p ) | 230 | V | | Secondary voltage (RMS) | ( V_s ) | 12 | V | | Secondary current | ( I_s ) | 5 | A | | Frequency | ( f ) | 50 | Hz | | Core material (grain-oriented steel) | – | M4/M6 | – | | Flux density (max) | ( B_max ) | 1.4 (for Si steel) | T | | Current density | ( J ) | 3 | A/mm² | | Window utilization factor | ( k_u ) | 0.4 | – | | Stacking factor | ( k_s ) | 0.95 | – | | Efficiency target | ( \eta ) | 0.9 | – | | Temperature rise target | ( \Delta T ) | 50 | °C | Use data validation for core material selection. 3. Core Sizing (Area Product Method) Formula: [ A_p = \fracV_p \cdot I_p + V_s \cdot I_sk_u \cdot J \cdot f \cdot B_max \cdot k_s \cdot (2) ] (Simplified: (A_p = \fracVA \cdot 10^42 \cdot f \cdot B_max \cdot J \cdot k_u) for 50 Hz)
Add : SWG #, bare dia (mm), insulated dia (mm), resistance (Ω/m). 6. Check Window Utilization Required window area: [ W_a_req = \fracN_p \cdot A_w_ins_p + N_s \cdot A_w_ins_sk_u ]
Add a with columns: Core name, ( A_c ) (iron area cm²), ( W_a ) (window area cm²), ( A_p ) (= (A_c \cdot W_a)), weight. 4. Turns Calculation Primary turns: [ N_p = \fracV_p4.44 \cdot f \cdot B_max \cdot A_c \cdot 10^-4 ] ((A_c) in cm²)
| Cell | Formula | |------|---------| | VA rating | = V_p * I_p + V_s * I_s (estimate ( I_p = (V_s \cdot I_s)/(\eta \cdot V_p) )) | | ( A_p ) (cm⁴) | = (VA * 10000) / (2 * f * B_max * J * k_u) | | Select core | From manufacturer table (e.g., EI, toroidal) – match ( A_p ) |
Get ready to see the Wimpy Kid world in a whole new way! Written and illustrated from the hilarious imagination of Greg Heffley’s best friend, Rowley Jefferson, the Awesome Friendly Kid series is filled with new adventures and vibrant stories that will have readers in stitches!
Click or scroll
through the books
transformer design calculation excel
| Winding | Current (A) | Bare area (mm²) | Wire dia bare (mm) | Wire dia insulated (mm) | Turns | Build (mm) | |---------|-------------|----------------|---------------------|--------------------------|-------|-------------| | Primary | =VA/(η*Vp) | =I/J | =SQRT(4*Aw/π) | from table | Np | =turns * insulated_dia | | Secondary | Is | =Is/J | ... | ... | Ns | ... |
[ N_s = \fracV_s \cdot (1 + reg/100)V_p \cdot N_p ] where (reg) = regulation (e.g., 5%).
| Parameter | Symbol | Typical Value | Unit | |-----------|--------|---------------|------| | Primary voltage (RMS) | ( V_p ) | 230 | V | | Secondary voltage (RMS) | ( V_s ) | 12 | V | | Secondary current | ( I_s ) | 5 | A | | Frequency | ( f ) | 50 | Hz | | Core material (grain-oriented steel) | – | M4/M6 | – | | Flux density (max) | ( B_max ) | 1.4 (for Si steel) | T | | Current density | ( J ) | 3 | A/mm² | | Window utilization factor | ( k_u ) | 0.4 | – | | Stacking factor | ( k_s ) | 0.95 | – | | Efficiency target | ( \eta ) | 0.9 | – | | Temperature rise target | ( \Delta T ) | 50 | °C | Use data validation for core material selection. 3. Core Sizing (Area Product Method) Formula: [ A_p = \fracV_p \cdot I_p + V_s \cdot I_sk_u \cdot J \cdot f \cdot B_max \cdot k_s \cdot (2) ] (Simplified: (A_p = \fracVA \cdot 10^42 \cdot f \cdot B_max \cdot J \cdot k_u) for 50 Hz)
Add : SWG #, bare dia (mm), insulated dia (mm), resistance (Ω/m). 6. Check Window Utilization Required window area: [ W_a_req = \fracN_p \cdot A_w_ins_p + N_s \cdot A_w_ins_sk_u ]
Add a with columns: Core name, ( A_c ) (iron area cm²), ( W_a ) (window area cm²), ( A_p ) (= (A_c \cdot W_a)), weight. 4. Turns Calculation Primary turns: [ N_p = \fracV_p4.44 \cdot f \cdot B_max \cdot A_c \cdot 10^-4 ] ((A_c) in cm²)
| Cell | Formula | |------|---------| | VA rating | = V_p * I_p + V_s * I_s (estimate ( I_p = (V_s \cdot I_s)/(\eta \cdot V_p) )) | | ( A_p ) (cm⁴) | = (VA * 10000) / (2 * f * B_max * J * k_u) | | Select core | From manufacturer table (e.g., EI, toroidal) – match ( A_p ) |
