Yii2 ActiveRecord rules()函数不能验证自定义属性？ [ 2.0 版本 ]

为什么我的完全没用呢？
自定义属性

    public $password_old;
    public $password_new;
    public $password_new_re;

/**
     * 验证规则
     * @inheritdoc
     */
    public function rules()
    {
        return [
            ['admin_email', 'required', 'message' => '管理员账号不能为空', 'on' => ['login']],
            ['admin_email', 'email', 'message' => '管理员邮箱格式错误', 'on' => ['login']],
            ['password', 'required', 'message' => '管理员密码不能为空', 'on' => ['login']],
            ['password_old', 'required', 'message' => '请输入原始密码', 'on' => ['change_pass']],
            ['password_new', 'required', 'message' => '请输入原始密码', 'on' => ['change_pass']],
            ['password_new_re', 'required', 'message' => '请确认密码', 'on' => ['change_pass']],
            ['password_new_re', 'compare', 'compareAttribute' => 'password_new','message' => '两次密码输入不一致', 'on' => ['change_pass']],
        ];
    }

  $form = ActiveForm::begin([
                    'fieldConfig' => [
                        'template' => '{label}{input}{error}',
                    ],
                ]);
                ?>
                <?= $form->field($model_admin, 'admin_name')->textInput(['class' => 'form-control', 'placeholder' => '请输入图书名称', 'readonly' => true]) ?>
                <?= $form->field($model_admin, 'password_old')->textInput(['class' => 'form-control', 'placeholder' => '请输入原密码']) ?>
                <?= $form->field($model_admin, 'password_new')->textInput(['class' => 'form-control', 'placeholder' => '请输入新密码']) ?>
                <?= $form->field($model_admin, 'password_new_re')->textInput(['class' => 'form-control', 'placeholder' => '请确认密码']) ?>

                <?= Html::submitButton('确认修改', ['class' => 'btn btn-primary']); ?>
                <?php ActiveForm::end(); ?>