Koncepti digitalnih filtrov za merjenje napetosti celic avtomobilskih baterij

Gačnik, Luka (author), Žemva, Andrej (mentor), Heiling, Christian (comentor)

Veliko povpraševanje po električnih vozilih zahteva hitro načrtovanje in razvoj varnostnih meril, ki se uporabljajo pri razvoju njihovih komponent. Ena izmed takšnih funkcij, ki izboljšuje varnost električnega vozila, je merjenje napetosti z uporabo analogno-digitalnega pretvornika Delta-Sigma. Da bi se odčitki podatkov pravilno odzvali na dejansko stanje baterijskih celic, je potrebno določiti ustrezno metodo filtriranja signalov. V primeru, da zunanje filtriranje ni mogoče, obstaja alternativa, kjer se motnje zmanjšajo v fazi naknadne obdelave. Ker je sistem opredeljen kot digitalni sistem, je mogoče uporabiti bodisi izvedbo s končnim impulznim odzivom (FIR) ali neskončnim impulznim odzivom (IIR). Razvijte program, ki simulira obe metodi digitalnega filtriranja v fazi naknadne obdelave analogno-digitalnega pretvornika Delta-Sigma. Za izračune uporabite programsko in računalniško okolje MATLAB in program Simulink za izdelavo analogno-digitalnega pretvornika Delta-Sigma. Konstruirajte poenostavljen model s pomočjo MATLAB skripte, če v primeru modela Simulink ni mogoč zadosten čas izvedbe modela. Z grafičnim uporabniškim vmesnikom ustvarite delujočo aplikacijo, ki bo omogočala visoko mero konfiguracije modela.

• Language: Slovenian
• Keywords: meritev napetosti, ADC, Delta-Sigma modulator, digitalno sito, FIR, IIR, odzivni čas, stabilnost, obdelava signalov. testno okolje
• Work type: Bachelor thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2022
• PID: 20.500.12556/RUL-140532
• COBISS.SI-ID: 121861891
• Publication date in RUL: 15.09.2022

GAČNIK, Luka, 2022, Koncepti digitalnih filtrov za merjenje napetosti celic avtomobilskih baterij [online]. Bachelor’s thesis. [Accessed 26 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=140532

Secondary language

• Language: English
• Title: Digital filter concepts for automotive battery cell voltage measurement

Abstract

The most important task of a battery management system on-board an electric vehicle is the battery cell voltage measurement. It enables the system controller to monitor the behavior and health of a battery pack, and respond appropriately, ensuring the safety of a vehicle. In order to provide valid data samples without external disturbances, an appropriate filter method should be implemented. In the case of a battery management system integrated circuit TLE9018DQU, the voltage measurement is based on the Delta-Sigma modulator. External filtering with required frequency characteristics is currently not achievable, due to limitations imposed by the passive balancing circuitry. For this reason, a discrete-time filter can be implemented in the post-processing stage of the Delta-Sigma analogto- digital converter. To provide an appropriate filtering method, the test bench environment was designed in the course of this thesis. The test bench was set-up using the MATLAB and the Simulink environment. A flexible configuration of the Delta-Sigma ADC and either the FIR or the IIR filter implementation is provided. Quantization of coefficients of a filter transfer function was integrated into the test bench to simulate the behavior of an practical filter design. Settling time of the IIR was evaluated and its possible improvements are discussed. At the end, an explanation is given on how the IIR is superior to the FIR implementation in the application for a TLE9018DQU integrated circuit.

• Keywords: voltage measurement, ADC, Delta-Sigma modulator, digital filter, FIR, IIR, settling time, stability, signal processing, test bench