# 修改图表标题和标签为英文
def plot_power_balance(self):
    """绘制功率平衡曲线"""
    fig, ax1 = plt.subplots(figsize=(12, 5))
    
    # 负荷侧
    ax1.stackplot(range(24), 
                 self.results['P_con'], 
                 [self.P_fixed] * 24,
                 labels=['Conventional Load', 'Fixed Load (H2/NH3)'],
                 alpha=0.8)
    ax1.plot(range(24), self.results['P_load'], 'k-', lw=2, label='Total Load')
    ax1.set_ylabel('Power (MW)', fontsize=12)
    ax1.set_xlabel('Time (h)', fontsize=12)
    
    # 电源侧
    ax2 = ax1.twinx()
    ax2.stackplot(range(24), 
                 self.results['P_wind'], 
                 self.results['P_pv'],
                 labels=['Wind Power', 'PV Power'],
                 alpha=0.8)
    ax2.plot(range(24), self.results['P_ren'], 'b--', lw=2, label='Total Renewable')
    ax2.set_ylabel('Power (MW)', fontsize=12)
    
    # 合并图例
    lines1, labels1 = ax1.get_legend_handles_labels()
    lines2, labels2 = ax2.get_legend_handles_labels()
    ax1.legend(lines1 + lines2, labels1 + labels2, loc='upper left', fontsize=10)
    
    plt.title('Typical Day Power Balance Curve', fontsize=14, fontweight='bold')
    plt.tight_layout()
    plt.show()